The most important choice of laser marking machine is its laser.So today I’m gonna to tell you something about four most common lasers.
1. CO2 laser /（CO2 laser marking machine）
CO2 laser marking machine principle: CO2 laser marking machine, or carbon dioxide laser marking machine (CO2 is carbon dioxide). It is a laser galvanometer marking machine using CO2 gas as working medium. CO2 laser marking machine is a CO2 laser with CO2 gas as the medium, CO2 and other auxiliary gases are charged into the discharge tube on the electrode to add high voltage, the discharge tube produces glow discharge, so that the gas emits a wavelength of 10.64um laser, laser energy amplified, after the galvanometer scanning and F-Theta mirror focusing, under the control of computer and laser marking control card. The marking of images, words, numbers and lines can be carried out on the workpiece according to the requirements of users.
CO2 laser marking machine consists of CO2 laser, 10.64 field mirror, 10.64 beam expander, CO2 laser power supply, scanning galvanometer, control computer, laser control card, laser control software, laser frame, laser circulating water system, circuit control system and other parts.
3）Advantages and application areas
The main features of CO2 laser marking machine are: using carbon dioxide laser, belonging to the general model, post-focusing mode, small size, high integration.
This machine is suitable for marking most non-metallic materials, such as paper packaging, plastic products, label paper,leather cloth, glass and ceramics, resin and plastic, bamboo and wood products, PCB board, etc. CO2 laser is a gas laser with a wavelength of 10.64 um in the far infrared optical band. CO2 gas filled discharge tube is used as the medium to produce laser. When high voltage is applied to the electrode, glow discharge is produced in the discharge tube. The gas molecule can release the laser, and the laser beam is formed after amplifying the laser energy.
2.Green laser /（Green laser marking machine）
Green laser marking machine uses high-power multi-mode laser diode pumped to produce green laser beam after laser frequency doubling, and then through computer control of high-speed scanning galvanometer deflection marking or cutting. Two laser beams are projected from different angles into transparent objects (such as glass, crystal, etc.), accurately intersecting at a point. Because two laser beams interfere and cancel at the intersection point, their energy is converted from light energy to internal energy, releasing a lot of heat, melting the point into a tiny hole. The machine accurately controls the intersection of two laser beams at different locations, creating a large number of tiny holes that eventually form the desired pattern.
2）Advantages and application areas
The green laser with 532 nm wavelength has obvious advantages: smaller spot diameter, more concentrated energy, high electro-optic conversion efficiency, good beam quality, marking accuracy below 10 micron level, neat marking frame, no explosion point, no thermal deformation. Mainly used in glass, crystal products, surface and internal marking, ceramics, metals, electronics, plastics and other products. It belongs to the category of cold light. It is also suitable for some products with high heat reaction and high precision.
Through photochemical ablation, that is, by laser energy to break the bonding between atoms or molecules, making it into small molecules gasification, evaporation. The focus spot is very small and the heat affected zone is very small, so it can be used for superfine marking and special material marking.
The main components of UV laser marking machine are: focusing system, trigger type, computer control system, laser power supply, laser, galvanometer field mirror scanning system, marking control software.
3）Advantages and application areas
Ultraviolet laser marking machine with its unique low-power laser beam, especially suitable for ultra-fine processing of the high-end market.iPhone, cosmetics, pharmaceuticals, food and other polymer packaging bottle surface marking; flexible PCB board; silicon wafer micro-hole, blind hole processing; LCD liquid crystal glass, glassware surface, metal surface coating, plastic buttons, electronic components, Communications Equipment, and other fields.
Optical fiber laser marking machine principle: Optical fiber laser marking machine is the use of laser beams in a variety of different substances on the surface of permanent marking. Marking effect is through the evaporation of the surface material to expose the deep material, or through the light energy causes the chemical and physical changes of the surface material to “engrave” out the trace, or through the light energy burns off part of the material, showing the desired etched patterns, text, bar code and other graphics. The so-called fiber laser marking machine refers to the use of fiber laser marking machine, fiber laser with small size (no water-cooled device, using air-cooled), light is good quality (base mode), maintenance-free and so on.
Fiber laser marking machine is mainly composed of fiber laser, high-speed scanning mirror, marking software, industrial computer and cabinet. Fiber laser is the core part.
3）Advantages and application areas
Mainly used in: plastics, electronics, metals, ceramics, tobacco and other materials marked out the required text,pattern, bar code and other graphics. Optical fiber laser marking machine easy to operate, fast marking, clear and other advantages, making the production efficiency of enterprises more efficient. Our commonly used pulsed lasers are 10W, 20W, 30W and 50W.
We design and manufacture automatic machine for the PCB/SMT and Thru-hole industries in Shenzhen China. We help companies looking to low cost equipment with smart, ROI-driven assembly equipment solutions.Contact us today to learn how we can help you。
Dear ,After many requests, we are thrilled to announce our Industry Leader Newsletter. As an Industry Leader, Southern Machinery wants to provide your company with the same excellence we put into our equipment and services. We know your job is important and you must always stay ahead of trends in PCB Assembly. Changes in labor costs, shifting environmental laws and policies, energy conservation efforts, advancing industries, international trade politics, etc., are causing a reemergence of in-house manufacturing systems to be put into place. The tide has shifted and it is now time to begin transitioning to a more self-sufficient manufacturing system.
Welcome to our SMTHelp.com Newsletter! No matter what your company role is, this Newsletter will keep you up-to-date with the most important topics and events that affect the quality and profitability of your manufacturing systems. If it has been a while since we last spoke, stay tuned! We will be delivering important PCB topics to your inbox. In the meantime, we have put a quality checklist together for you!
Your Manufacturing Quality Checklist here:
Do you have ROI-Driven Design and Implementation of reliable PCB Assembly Equipment?
Is your equipment Low-Cost with High-Intelligence?
What is the speed of your PCB throughput?
Is your efficiency high?
Is your productivity high?
Are you increasing your profits by using affordable and reliable equipment?
Is your short-term investment low?
Is your long-term investment low?
Have you eliminated hand insertion for Automatic Insertion for improved time and profits?
Finally, have you eliminated your import fees by producing your own PCBs?
Nowadays, the market competition is more and more intense, how PCB assembly plant in such an environment can to be invincible. The first point is to reduce its production costs. To achieve this goal, the most important way is to improve the production efficiency of the production line. This paper discusses some measures and measures to improve the efficiency of SMT production line based on the author’s work practice.
一. Processing of chip mounting program
SMT production line consists of a number of equipment, including screen printing machine, chip mounter, reflow soldering and so on, but in fact the speed of the production line is determined by the chip mounter. A SMT production line usually consists of a high-speed machine and a high-precision chip mounter, the former mainly mounting chip components, while the latter mainly mounts IC and Odd-form components. The entire SMT production line has the maximum production capacity when the two patch machine completes an affixed time (hereinafter referred to as the mounting time) and the hourly hour. In order to achieve this goal, we can process the mounting procedure according to the following methods.
Load distribution balance. Reasonable distribution of the number of mounting components of each device, so as to make the installation time of each device equal. When we first assign the number of mounting components for each equipment, there is a large gap in the mounting time. This requires the adjustment of the production load of all the equipment on the production line according to the mounting time of each equipment, and the part of the equipment on the equipment is moved one part to the other. The balance of current load distribution.
Equipment optimization. Each patch machine has a maximum value of the patch speed, for example, the YV100 of YAMAHA is called 0.25 seconds / slice, but in fact the speed value is realized under certain conditions. To optimize the numerical control program for each equipment, it is to make the chip mounter meet these conditions as much as possible in the production process, so as to achieve the highest speed mounting and reduce the installation time of the equipment. The principle of optimization depends on the structure of the equipment. The placement machine for X/Y structure is usually optimized according to the following principles.
As far as possible, the mounting head can be picked up at the same time.
When arranging the mounting program, the same type of components are arranged together to reduce the number of changing suction nozzles when the mounting head picks up the components and save mounting time.
More supplies should be placed near the material station near the PCB.
During the process of picking up and releasing, try to collect materials only from the front or rear material stations, so as to reduce the moving distance of the head.
In every cycle of collection and circulation, the head should be loaded.
Notice: Some principles will conflict when optimizing the program, which requires compromise consideration to select the best optimization plan. Optimization software can be used in load distribution and equipment optimization. The optimization software includes equipment optimization program and production line balance software. The optimization procedure of the equipment is mainly to optimize the placement procedure and the configuration of the feeder. After the components BOM and CAD data are obtained, the mount program and the feeder configuration table can be generated. The optimization program will optimize the movement path of the mounting head and the configuration of the feeder, and reduce the moving distance of the mounting head as much as possible, thus saving the time of the mounting. The production line balancing software is an effective tool for the optimization of the whole production line. The optimization software adopts a certain optimization algorithm. The current optimization software has been intellectualized, and the optimization process can be completed faster and better.
二.Eliminating of bottlenecks
The SMT production line is made up of a number of automatic equipment. When a certain equipment is slower than other equipment, the device will be the bottleneck for the speed improvement of the whole SMT production line. According to a sample of 19 factories (Table 1), bottlenecks are often found in chip mounters, and only by adding chip mounters can they be eliminated. Of course, this requires a large amount of capital investment, but it can make full use of the production capacity of other equipment, far more than the investment of a SMT production line. What type of patch machine is added depends on the bottleneck of the production line. In general, it is best to buy a high speed, multi-functional chip mounter machine, because it has the features of both high speed and high precision machines. The range of mounting components covers the high precision machine and the high speed machine. It can solve the problem caused by the high speed machine or the high precision machine. Bottleneck problem. At present, the development trend of chip mounter is also developing in this direction to meet the needs of the market.
Bottleneck of process steps
High precision chip mounter
High Speed Chip Mounter
Online testing (ICT)
Table 1 –Distribution of the most common bottlenecks in a factory
Adding a patch machine to the production line can solve the bottleneck problem and speed up the pace rate. This method provides more production capacity and more feeder position to better balance the production line without significantly increasing the complexity of production line management, which is much more than a single increase in the production capacity of a chip mounter machine. It’s much more powerful.
三.Implementing strict and effective management measures
1.SMT equipment is a precision equipment of mechatronics. Strict and effective management measures are an important way to improve the efficiency of SMT production line. If the components to be supplemented in advance are installed on the standby feeder, the production line will assemble the last few pieces of the batch number in front of the front, and do well the preparation of the next batch of products on the production line and so on.
2.The SMT production line is a large production line, and the output value is calculated in seconds. And the fluency of production and quality of products, besides equipment and environmental factors, human factors play a very important role. For example, if the operator is familiar with the equipment, it will take less time to eliminate problems in the production process, and it will also save production time and improve production efficiency. Therefore, we must attach great importance to the training of employees. In addition to regular professional training, some professional SMT books and periodicals should be used as teaching materials to organize the staff to learn, to cultivate the love of SMT and to improve the comprehensive business level of each person.
3.Regular inspection and maintenance of SMT equipment is also a powerful guarantee to ensure its full effect. Many companies often neglect this because of their heavy production tasks. Once the equipment fails to produce normally, the loss caused by the shutdown is far greater than the cost of regular shutdown inspection and maintenance of the equipment. Therefore, we must emphasize the regular inspection and maintenance of the equipment, so that the equipment is in good condition.
SMT production needs high investment, but if the management and use is appropriate, and pay attention to several aspects mentioned above by editor , It will fully tap the production potential of the SMT production line, improve production efficiency, in a few years will take back all of the investment, to achieve “high input, high output”.
Automatic wave soldering machine is currently the mainstream of electronic products welding process, compared with other manual welding with a variety of manual, has unparalleled advantages, and thus widely used by electronics manufacturers. The automatic claw wave soldering machine produced by our company is the most advanced using modern high-tech technology.
The new design of crystallization:
(1) Unique automated preparation program;
(2) Perfect work/adjustment function;
(3) The temperature is controlled by the temperature control table of WINPARK. The speed is high and the precision is high. It is suitable for long-distance transmission in harsh industrial environments and has high reliability.
(4) The chain speed is controlled by the frequency conversion speed control motor, which is easy to adjust.
(5) Solder joints are of high quality, easy operation and good service. They are reliable products in this industry.
Thank you for your inquiry and use this machine, thank you very much! Before use, please read this manual carefully. It will provide you with all the functions of the machine thoroughly, and it will be fully utilized in production.
a) Confirm that the machine is connected to three-phase ac380v, 5- line power supply and ensure the machine is grounded properly.
b) Open the total air switch and the switch in the electric control box, then open the power switch on the operator panel.
c) The machine Time control switch is lit, at this time presses the manual/The automatic switch icon, the time control switch displays On state, touch screen lit
d) Touch ( enter ) the button until you enter the operating interface, please refer to the instructions.
3.2time-controlled switch operation instructions
Instructions for use (Time controller is not used for a long time, every three months need to charge once, the charge times <12 hours)
1. first use, or long time after use, when the controller is not displayed, please after the power, with small items in the lower left corner of the hole open.
2. when powered on, the timer is 24-hour system, please hold the “clock” key for 5 seconds, the monitor will display AMin the upper left corner, indicating that it has been the hour system. Press 5 seconds and return to the hour system, at which time AM display is turned off.
(12 hours When AM is the morning, PM means the afternoon)
3. Set switch time: (if the set opening and closing time is the same, the time controller relay suction for a second ) set steps:
Set up a project
Press (SET) (设定)
Enter timed setting (show 1 on)
Press (Week) (星期)
set every day the same, or week 1-5 the same, week Six Sunday the same, or daily different (if the same daily, you can not press this key, this time does not show the week, while correcting the clock also
No need to press this key)
Press(time) (时)(分 )
Set Time to open
Enter the timer setting (show 1 off)
Press(time) (时 )(分 )
Time to set off
Press (week) (星期)
If the date of the set off is the same as open, you may not press this key
Repeat 2-6 steps
Set the 2-8 times switch time
End Time setting
* If you do not need 8 switch timing, press (clock) key can be into the clock correction.
* If set error or cancel set this press (clear)(清除) key, and then restore the original settings once again
* Display without setting (–:–)
4.1Press Live (Clock ) and repeatedly press (week ) to the same day. ( if the daily set switch time is the same, can not press this key, direct correction time, points)
4.2Press and hold (the clock) and adjust the time by (time) or (minutes).
5.when you have completed the above operation, pressThe Open/Auto/ off ” key, be sure to base your current time on the set of self
controls the time switch, causes the monitor the most downlink to display as (on / off ) or at off(auto / off)
Indicates that the timer is in automatic control and in the open state
Indicates that the timer is in automatic control and is off state
Indicates that the contact is in a connected state but the timer does not switch on the set switch time
Indicates that the switch time is invalid in the long shutdown state.
6.check: Press (set) key to check whether the time set is correct.
7.Modify : please press (clear ) The key at the setting , then reset the time and week of the timing switch.
8.End check: Press (clock) to finish checking and setting, display clock.
9.Manual control: Press (ON/off/off) key, can realize random switch
1.Open The setting of time, can not cross set, should be set according to the order of time.
2.Implement timing Switch Controlsystem Time to set the state in the auto , that is, show on / off (on) or from Move / Close ( at off).
3.The use of the environment should be in line with the environmental requirements of the controller, to avoid vibration, shock, corrosion, dust, electrostatic, high-temperature, high-temperature, direct sunlight environment to use.
4.Please store it in the rated voltage and temperature and humidity condition.
5.maximum current refers to the maximum current when resistive load, lamp current = rated current x20%, motor current = rated power Flow x30%, please use in the specified voltage and current range, if exceed the specified capacity, please contact the AC contactor.
Chapter 4 Interface Operation
4.1 when the machine electric source button is opened , touch the screen into the Welcome interface ( figure 1 ), waiting about Ten seconds, after the completion of the PLC , the machine automatically open tin furnace heating function.
Figure 1 Startup initial interface
4. 2 Click to touch the screen into the Secretary to introduce the painting surface, such as ( figure 2) Click into the system
Figure 2 Company Introduction
4. 3 Click into the system , touch the screen into the machine to manipulate.the painting surface , as 3.
This painting surface controls all the operation of the machine,
including the manual mode and the self – moving die style.
4.3.1 : Manual mode: Touch screen left upper corner display manual (click to Automatic), manual mode, click Transport, open the chain claw
transport function; Click Preheat, turn on preheat function (must turn on transport to turn on preheating); Preheat temperature to reach, click on the peak, according to the actual product to open the crest, unicast or double wave (long leg wave soldering only a valid), generally only in the back of the red glue patch components need to open the double wave, at this time the peak has been running , the technical personnel can adjust the crest height according to the actual situation; Click on the spray, click the spraying, spray has been working, at this time can adjust the spray size, close to spray, the spray becomes automatic state.
4.3.2 : Automatic mode: Click on the touch screen in the upper left hand corner of the manual switch to Automatic mode, point Open Transport, preheating, as needed to open the crest, spray fog. In the manual mode after adjusting the machine state, at this time the machine can be normal production, when the circuit board into the machine, machine automatic spray, automatic spray, automatic wave soldering.
4. 4 Click on the machine in the lower right corner of the EEG map , the machine into the set interface , as shown in Figure four , this screen is used to set the machine‘s shipping parameters. Spray Distance: This parameter sets the automatic spray time when PCB The board is
transported to the top of the sprinkler start spray, recommended set value to 7 , if PCB
The office has not reached the top of the nozzle has been opened Start Spray, then change
this parameter large, conversely, if PCB after the board is over the nozzle before
beginning to spray, then the parameter is adjusted small;
Spray coefficient: This parameter is not set;
Wave Distance: This parameter is automatic Qipo parameter, when the PCB board is
transported to the front of the tin Furnace, automatic Qipo, this parameter and spray
distance set the same way;PCB board in distance tin furnace 20cm
The peak effect is the best when it is opened.
Wave time: This parameter is the peak after the automatic start of the operation time, it is recommended to set the 50-80.
Figure 4 parameter setting screen
4. 5 Click Control Screen left -pointing arrow chart , into the machine– like monitoring Screen , this screen is used to monitor the operation Status of PLC .
Fig . 5 The status monitor drawing surface
Chapter 5 Installation Adjustment and Commissioning
5.1 Machine Adjustment
After the machine positioning, the level adjustment, first the Foot Cup, so that the rubber wheel off the ground water leveling ruler on the machine to adjust, must make it in a horizontal state.
Adjustment of rail height
(Note: Tin furnace before shaking out, the first tin furnace trolley and rack fixed connection code loosened, and then the tin furnace height lowered, so that the tin furnace nozzle and titanium Claw in the height of a certain gap to avoid damage collision.) The tin furnace can be smoothly shaken out. Note: The foot wave soldering furnace to disconnect the titanium claw first
5.2 Adjustment of Plate feeder
Installation of the machine to install the first access to the plate feeder, the board will be connected with screws fixed, with two
PCB Board to adjust the docking plate, a piece of PCB into the titanium claw inside clamping, a PCB board placed in the plate feeder, two PCB board docking up, By adjusting the plate to the side of the four screw wire To adjust the height of the board connection, so that the two PCB board height parallel, through the adjustment of the machine, such as plate connected to the side of the rice screws to adjust the parallel to the plate feeder and titanium Claw, two fast PCB The joint of the plate butt is completely kissed so that the plate feeder has been installed and adjusted.
Adjustment of 5.2 guideway width
The width of the guide rail can be adjusted according to the different width of the printed board, the printed board Pinto on the Import board, and the printed board side to the fixed edge of the import plate, the rotation width adjustment handwheel to the printed circuit board can be placed on the guide, and can be moderately pushed to the conveyor chain claw mechanism
1. Can not hold too tight or loose, too tight will cause the chain claw and plate deformation; Taisong may appear drop board or PCB side stop affect the quality of welding.
2. before adjusting the width of the chain to check whether the two sides of the solder furnace nozzle plate, if you can touch, it is necessary to increase the guide or reduce the tin furnace, so that the chain claw higher than tin furnace spout Guide.
5.2 Adjustment of Tin Furnace
The height adjustment of the tin furnace can be completed by the tin Furnace trolley lift, and the height standard is approximately 6mm~8mmfrom the top edge of the nozzle by the base board component foot.
5.3 Conditioning of preheating box
The position of the preheating box is fixed before leaving the factory, and can not be easily changed, the preheating box should ensure the bottom
The temperature of the face is between the 80℃-180℃.
5.4 adjustment of flux spray height
The spray height adjustment is done by adjusting the nozzle height and adjusting the appropriate air pressure and gas.
Loosen the screw that the nozzle is connected with the shaft, the nozzle can be moved up and down, and appropriate adjustments can be made according to the actual needs.
* The adjustment of the volume of wash claw liquid. (see chart below)
4.- Chain Claw
The claw pump has a switch control in the touch screen and requires alcohol in the alcohol box and turns on the drive Chain to open
Claw Washer is to ensure that the chain claw clean, to achieve solder quality one of the factors. The device uses a loop-back -flow design, the chain claw through the alcohol moist brush cleaning, flow through the control valve. The capacity of the alcohol box should be Paute 2/3 or more, otherwise the pump will burn, every two days will wash the claw box out of the tin slag clean.
Note: Do not turn the adjustment switch too large and the alcohol overflow machine, so as not to cause a fire.
after the equipment is installed, the equipment should be fully checked, and after the system and mechanism are working normally, then put into normal use.
* Prepare Equipment
flux approx . 20L
Cleaning Lotion about 12L
Solder lead -free solder 400kg
Electric Stove 3Kw 1
Stainless steel tank 1
* Molten Tin
The solid solder is poured into the stainless steel container in batches, heated to the furnace to fully melt ( about the℃ ), and then poured into the tin tank of the equipment, when the solder liquid surface is about 8mm from the tin Groove mouth , Stop feeding start-up equipment, the tin furnace temperature preset for 245℃, to tin furnace temperature, start the crest, adjust the crest height, check whether the crest is normal. Josi surface is low, at this time can be the bar-shaped solder directly into the tin furnace, adjust the tin surface to fit. Note:a. Tin Tank for the first time, the Solid Tin Bar ( block ) material directly into the tin furnace to melt, In case a large amount of heat can not be passed to the solid solder in time, resulting in high-temperature burning tin trough and heating pipe. b. Before dissolving the tin, the tin trough and the stainless steel container should be cleaned to prevent the impurity from polluting the solder.
* Check Flux Spray Condition
The flux is injected into the rosin groove, connected to the gas source and activated. “Spray Fog ” , check whether the spray is normal. the proportion of flux in accordance with the requirements of manufacturers and actual use of the situation, can be 0.80~0.87 within the scope of appropriate adjustments. ( manufacturers are best to provide free cleaning flux)
Check the transmission, adjust the body is normal, respectively, start the transport, washing claws, cooling, preheating and so on, check is normal, commissioning completed.
Chapter 6 Inverter Description
(See VFD-M Manual and temperature control sheet , This manual is presented in conjunction with the instructions )
Chapter 7 Spray Type Rosin Furnace
7.1 composition of rosin furnace
Rosin furnace is made of stainless steel, sealed containers, flux stored in this will not evaporate and absorb moisture in the air, and maintain a stable solvent composition, and with high-precision import nozzle and Germany or the United States rod-free cylinder, imported light eye, is currently the most ideal welding equipment users. The structure is shown in the figure below.
7.2 correct use of rosin furnace
the height of the rosin spray can be adjusted (see spray height adjustment), can also adjust the solenoid valve on the airflow regulator or pressure regulator on the air conditioner, the factory has been adjusted so easy to change, to avoid making into the spray system chaos, when working when the substrate through the input photoelectric tube, time control system started, and began to delay spraying and spraying tin until the substrate through the rosin furnace 3-5 seconds to stop spraying.
Note: The flux must be clean-free type, which is characterized by the plate surface after welding without ultrasonic cleaning, clean and beautiful board.
7.3 instructions for the use of nozzles
I, the safe operation of the case of special attention to the following matters:
7.3.1. Take appropriate precautions before use to prevent injury to the human body or damage to the product.
7.3.2. Do not point an open flame or close to an open fire place, to avoid static electricity.
7.3.3. In the installation or maintenance process should be all fittings with raw tape, such as the connection slack, in the gas
Under the pressure of the body, various liquids will be sprayed into the body.
7.3.4. When connecting the air pipe and the solvent pipe, please select different material and pay attention to the pressure of the hose can not exceed the regulation, do not use the damaged old trachea.
7.3.5. Often clean the nozzle on the solvent, the residue on the road, may cause trouble, is in the direction of people can not press the switch.
7.4.1. after Regular cleaning nozzle to ensure smooth nozzle.
7.4.2. always keep the liner slide clean and lubricated, no solvent immersion, so as not to affect the rod the normal use of cylinders.
Chapter 8 Preheater
8.1 the role of Preheater
The role of preheater is to increase the expansion rate on solder pads by preheating the flux activation and
To promote the evaporation of the PCB flux solvent, thus obtaining the best soldering effect. In addition, the circuit board after preheating, reduce the PCB and tin furnace temperature difference, to avoid the thermal impact of electronic components and circuit board sudden thermal deformation.
the optimum temperature for preheating is 120~180℃. The temperature is too high can cause undesirable consequences; too low temperature affects welding quality.
8.2 The construction of preheating box
the preheating system is composed of imported blackbody heating pipe. The Preheating box and the guide rail are connected by screws to facilitate the inspection and maintenance of the line.
The best preheating temperature on the circuit board is 120-180 ℃, the temperature of the preheating box is passed by the high accuracy temperature probe to the preheating electronic thermostat to adjust, can accurately control the preheating box temperature, protect the circuit board, achieve the most ideal preheating effect.
8.3 Daily Maintenance and Precautions
8.3.1 The temperature of the circuit board’s bottom surface is often tested to ensure that 120~180℃ between the two to ensure the best solder effect.
8.3.2. Check whether the circuit wire aging, in order to prevent current interruption.
8.3.3. Clear the flux residue in the drawer of preheating box, lest the set will cause fire.
Chapter 9 Tin Furnace
Tin furnace structure using stainless steel production. By the wave generator, nozzle filter, impeller, motor and other groups
Yes. The use of pump-type principle to form a crest.
Tin furnace structure is reasonable, high technical content, the use of Japanese and American tin Furnace advantages of the development of high standard tin furnace. Its characteristics:
1 reduce the tin oxidation to a minimum.
2 nozzle wave smooth, tin surface can be adjusted vertically to adapt to different PCB board welding requirements,
3) External heating effectively avoids the phenomenon of explosion tin, good insulation performance, tin furnace durability does not deform.
Tin furnace body is by corrosion-resistant stainless steel plate welding into, heating tube installed in the tin furnace two outside. Use
Plate to radiate heat, so that the temperature uniformity of the tin furnace, the overall heat balance does not deform, spray cavity set up without clogging nets,
Can keep the peak smooth and smooth, and not plug, thus reducing maintenance, improve efficiency.
9.2 correct use of tin furnace
Tin Furnace high and low and in and out of the mobile can be used to set up the joint hand wheel and lifting screw adjustment , adjust the tin Furnace crest can be adjusted by the frequency converter, the higher the impeller speed, tin furnace crest is higher;
Solder temperature controlled by the thermocouple in the tin Furnace. First of all, the expected solder temperature set, usually the normal solder temperature is 230-250 ℃.
In the back of the tin furnace with a row of tin Tsui, used to clear the tin furnace. The tin furnace to the back of the removal, cleaning and maintenance, before the tin furnace removed, must first be the guide rail high or tin furnace to reduce a certain height to avoid the rail chain claw and tin furnace collision caused by the chain claw deformation.
In the demolition of the furnace, referring to the structure shown above, the nozzle removed first, the motor frame and impeller out, loosen the furnace liner fastening bolts, you can remove the furnace.
9.3 Daily maintenance and precautions
9.3.1. Regularly check the amount of tin to control the “spray tin wave.”
9.3.2 . measure soldering temperature with mercury thermometer ( standard temperature0℃). If the preset solder temperature is unstable , it can be adjusted in the temperature control table.
9.3.3. Depending on the resulting oxide, add antioxidant grease. (Anti-oxidation grease and flux supporting use)
9.3.4. Frequently remove oxides from tin furnaces.
9.3.5. Check the tin furnace motor coupling on the machine rice and impeller shaft coupling machine meter and its operation, to ensure its normal operation.
9.3.6. Pay attention to check the wire has no aging, as well as the parts of the screws, nuts are loose.
9.3.7. Spray nozzle every day after work with alcohol automatic cleaning, lest block.
Chapter 10 Maintenance and precautions
1. Often the fuselage, transport, claw pump, cooling fan, such as motor housing cleaning to facilitate the cooling and insulation.
2. Regular inspection of electrical control box in the electrical appliances and fastening the screws on its terminals, such as the discovery of contact ablation, suction and not flexible, etc., should be dealt with in a timely manner.
3. Regular inspection of preheater, tin furnace heating pipe joints, such as the discovery of head loosening, poor contact, insulation aging and other phenomena should be tightened, clean and replace.
4. Regular inspection of equipment to protect the grounding device is good.
5. In the operation of the equipment, pay attention to monitor the shell temperature of each motor, overheating phenomenon should be stopped check.
6. When the general switch on the power supply, should first stop the tin Furnace, preheating and wave crest and other large current load before entering
7. After the main power switch trip, you must find out the cause of the failure, before the closing.
8. In the process of melting solder and injecting high temperature liquid solder into the welding furnace, wear protective articles to prevent
9. Flux, Wash claw liquid are flammable materials, use should pay attention to fire safety.
Ten after working every day, you need to clear the flux residues in the preheater to prevent accumulation. cause an open flame.
11. The limiter can not be added lubricating oil, so as to avoid the transmission chain claw not go.
12. Anti-oxidation wax (oil) should be used with flux to avoid fire.
13. Each transmission part should maintain the good lubrication, except the angle adjustment mechanism may use the ordinary ointment, other all uses the High-temperature ointment lubrication.
14. The tightness of each transmission chain should be checked and adjusted regularly.
15. Regular inspection of tin furnace speed motor lubrication and operation, to ensure its normal operation.
– Tin furnace Nozzle should be based on the peak stability, the peak when the exception to clean the nozzle, so as not to affect welding quality.
18. Spray nozzle should always check the tightness of its connection.
Chapter 11 Wiring
This equipment needs external 3φ , ac380v,50HZ power supply ( three-phase five wire system ), power supply capacity
The quantity is not less than 20KVA, the equipment shell should protect the grounding, the grounding resistance ≤4Ω, the grounding conductor is not less than
4mm2, the incoming line should be no less than 6mm2。
Chapter 12 General Trouble shooting
To ensure high quality, the devices used in the equipment are advanced industrial countries of high-quality products, such as million
In the event of an accident, please check each of the items listed in one table. If you are still unable to resolve, please contact the company directly.
All action buttons are invalid
1. Time is not in the state of timing
2. The tin temperature is not up to the set value
1. Set the scheduled boot time before the current time.
2. Wait until the temperature of the tin furnace, then operation.
Control power LED not lit
1. Power supply Missing phase
2. Fuse on the bottom plate of the electric vessel
1. Overhaul power supply.
2. Check whether there is a short-circuit phenomenon in the lights, etc.
In addition to the failure, replace the new insurance pipe (4A).
Power supply Total Switch tripping
1. Load and line occurrence short-circuit phenomenon
2. Power supply Total Switch Contact bad
1. Check the load and related lines, troubleshooting short-circuit.
2. Check the wiring area of the power supply master switch for appearanceloosening, heating, oxidation and whether the switch contact point is outcontact is bad, ablation and other phenomena, or to be seized
repaired or replaced.
Tin Furnace or preheating
Slow warming of the device
1. Power supply is too low
2. Additional Hotline(tube)partially damaged
1. Improve the quality of power supply.
2. Replace the hotline(tube).
Transport Claw not running
1. Transport motor shaft end of the drive chain skid, Force nut Loose
2.chain speed set to “0”
3.fx-2da or inverter damage
1. Fixed nut for fastening drive sprocket.
2.chain speed set to not “0” position.
3.fx-2da or inverter.
Failure and solder welding problem analysis
Press the button to press,But the LEDs are not lit
1. Total switch not open, emergency stop switch not open
Clean copper foil and component ends;PCB, components for long-term storage, research flux is no problem, for new flux.
Out of the tin pillar
1. Copper foil surface, component ends of oxidation and pollution
2. Solder welding of flux is not good
3. The chemical changes of the coating flux and copper foil4. Flux metamorphism
Clean copper foil surface, fully preheat, Preheat temperature standard: Aldehyde circuit board to
– ℃, epoxy circuit board120 to℃
(Solder surface temperatureadjustment flux, eutectic solder , temperature for250~260℃ circuit boardand tin liquid contact do not exceed the road plate thickness of the 1/2. Reduce the height of the tin liquid to adjust the speed of transmission , research circuit board design, in
Circuit board coating Protective film.
The occurrence of the lap
1. Copper foil surface, component ends of the oxidation of pollution
How SMT workshop planning? It turned out to be so useful.
How SMT workshop planning!
And only after the plant began production found that some areas have not planned beforehand, need to be adjusted, resulting in a waste of human and financial resources and valuable production time.
Therefore, it is important to check in advance SMT factory layout, especially for new SMT factory business, because there is no experience in SMT plant layout, the need to pay attention to the elements is not very clear, if we find a problem in the layout after production point, will cause some unnecessary losses.
So, when doing layout SMT plant, what to pay attention to what matters in advance to do to prepare? Here actual cases where we work to and we explore this problem.
planning SMT line configure
the client recent planning new on two identical SMT production line, specific device configuration (see FIG. 1) and the size of the apparatus is as follows: According to Figure 1 can be seen, the maximum width of the production line equipment is 1.71 m, the length of all devices sum is 13.6 meters, will add future planning a production line (line bulk on equipment configuration).
Workshop length 36 m, width of 12 m, an area of 432 m2, on the ground floor of the factory. Currently common ground for the shop floor, and no established anti-static system, can not meet the requirements of SMT antistatic workshop, but two conductive ground terminals, can establish subsequent workshops antistatic SMT system. Further, there is no air conditioning workshop and humidifiers, can not meet the requirements of SMT workshop temperature and humidity control. There workshop ventilation system, back to meet the requirements of the reflow furnace equipment. Workshop sufficient power to meet the electricity needs of all equipment in the workshop. There are two entrances whole plant, as are required to meet the equipment, raw materials and semi-finished channel. Special materials warehouse in another workshop, the need for planning. Good lighting conditions in the workshop, to meet the brightness of the SMT shop lighting requirements all stations. Whole plant layout situation shown in Figure 2.
1, the current new move into production lines and related aids, regional positioning;
2, the whole plant to meet future erection and production requirements three production lines, without planning zone realignment;
3, each production line starting position as consistent as possible, so that the whole plant orderly arranged in three lines.
analysisthe customer’s request, we first analyzed how the production line positioning; and before locating the production line, we consider the following points:
1, SMT equipment should avoid column and they maintain a certain distance, the distance is equipment installed at least after a good feed material by a vehicle;
2, SMT crossing equipment required for frame division pitch, and the crossing equipment to extend outwardly after the device installed above the material 50 cm;
3, optimal spacing of the two lines spaced more than 1.2 meters between the outer frame;
4, check the wire tail is generally a repair plan area, quality control personnel can perform sampling line tail region.
Based on the above considerations, the length of each line should be at least 13.6 meters (without regard to the maintenance area and the tail, the case where the sampling area and the thread area kanban), the width should be 2.7 meters (SMT feeding both surfaces), specifically as shown in Figure 3.
Therefore, the production line is positioned in substantially considering plant shown in FIG. 4.
Some details of the requirements of SMT plant layout
after determining the approximate location of the production line, when the need to consider some details of SMT production line requirements, and then to determine the exact location and the location of other auxiliary equipment SMT line.
First, we analyzed the SMT line position and aids required for each area requirements: 1, fire extinguisher drop zone;
fire extinguishers to be placed around the side of the post and SMT plant, placed according to the requirements of fire regulations.
2, the car rack placement region; car rack replacement for SMT production line models and switching material, in order to facilitate production and to improve the efficiency of replacement materials, preferably the vehicle is placed near the rack placement machine.
3, stock units rest area;
stock table mainly used in the production process and dryer materials stock preparation before switching, therefore, to be placed near the preparation station placement machine, and the best car rack together, Preparation facilitates directly on the car frame after a good feed material.
4, the shelf rest area printing station;
printing station for positioning the shelf aids in the production of printing presses, such as wipes, paste, alcohol, etc., to be placed in the vicinity of the printing press to facilitate removal use, improve Productivity.
region comprising placing solder paste storage refrigerator, solder paste mixer, paste warmed cabinets, can be placed next to the plant as required or uprights placed around a fixed area of the plant, However, to facilitate the operator to take place.
6, visual inspection after the furnace area, maintenance area;
in order to facilitate visual inspection after reflow and rework semifinished product, a shelf generally placed in the furnace, designed for the visual inspection of the furnace and rework.
7, screen placement area;
drop zone comprises a mesh screen plate was placed cabinet, stencil cleaningmachine, inspection tools, screen, stencil for storing, cleaning and inspection screen tension, etc., while in the region as much as possible to facilitate the production screen to take place.
8, garbage drop zone;
Production waste mainly from two parts, wipes and the like used in one printing operation, the second is to replace the waste tray and waste material produced with the like. Garbage two parts is generated to be placed separately, specialized recycling, in particular waste presses used. Thus, waste area may be placed next to the press machine or patch, or set beside the column region refuse placed separately placed.
9, kanban placement region;
kanban including the SMT billboards and other signage quality management, may be centrally located on the entrance into the shop, and also set up the production line Kanban state in which each head of the line, in order to view the producers and managers, promptly understand the current state of production status and quality SMT workshop and so on.
10, product placement area;
include products produced finished products in two parts, to separate the two partial regions divided out, strictly distinguished, in order to avoid confusion.
11, SMT placement of spare areas;
Nozzle including the SMT spare parts, a motor, a belt, cylinder or the like, to be placed in a special area, to facilitate the production of access.
12, location area temperature and humidity;
temperature and humidity conditions in order to better understand the SMT plant, depending on the size of the workshop area, several appropriately set the temperature and humidity measurement area, generally placed on the production line next to the column or wall.
13, SMT workshop office area;
let engineers and technicians and management personnel in office SMT shop floor, which can solve the problem on technology and management encountered in the production, to ensure the smooth operation of the SMT production lines.
14, anti-static protection area;
entry into SMT workshop area must have good anti-static measures. You may delineate the area in front of the plant, including the replacement of static clothing, shoes, hats and so on each employee’s locker. Also, the establishment of regional designed to test the static ring in SMT workshop at the entrance, so that each employee to do static loop testing and record test results before going to work. Based on the above analysis, the results of this SMT plant layout is shown in Figure 5.
In addition, SMT workshop also meet other requirements: 1, anti-static processing;
shop floor must be anti-static treatment, a common anti-static conductive flooring and paint and other ordinary places, customers can choose according to the actual situation. In addition, anti-static system must be set up in the workshop, to meet the requirements of the entire anti-static SMT workshop.
2, air-conditioning and a humidifier; SMT workshop to meet the requirements of temperature and humidity control.
3, the material management requirements;
in the warehouse, with particular attention to the way the material is stored, reel packaging methods, the use of hook-type place, wetting elements employed Cabinets for placement shelves to be treated with anti-static manner.
4, patch equipment gas and electrical circuitry;
preferably introduced directly from the production line at the down side of the roof, is arranged below the gas passage in the device and circuit wrapped with wire groove.
5, the ventilation system requirements;
needs to be installed to meet the requirements of the three power lines of the blower, and the third exhaust port reserved line.
1, according to the size of production line and the size of the entire plant SMT, completed the reasonable position of the production line; and
2, for aids, regions, etc. SMT production lines need to make the corresponding position location; 3, according to the SMT the characteristics of the plant, some of the necessary factors to consider in planning, in particular, anti-static; 4, in accordance with the requirements of the current situation and future development of the factory has been take into consideration, unified planning.
For SMT plant layout, but also requires a combination of size and product requirements and other plants to consider a number of factors, but to stimulate here.
Use of PCB Pallets in Wave Soldering
Patch components are used more and more on the circuit board, but there are still some perforated components between them. For this kind of board, selective soldering is the best solution, but not every company has enough funds to purchase selective soldering equipment, or the number of this type of circuit board is too small, specifically to buy selective soldering equipment is not Cost-effective. Manual welding is prohibited in certain industries such as the automotive industry
Therefore, in PCB wave soldering, using trays to block those patch components is a good method: reliable, fast production, and adaptability to high-capacity requirements.
The benefits of using trays:
Lead-free soldering requires higher soldering temperatures. Therefore, the circuit board is more easily bent during welding. The tray provides maximum protection of the circuit board during soldering and prevents bending.
Similarly, in the automotive and consumer electronics industries, many special-shaped circuit boards have emerged for the needs of applications. It is sometimes difficult to transport these shaped plates with conventional chain rails and mesh belts, and placing the circuit board plates in trays allows any type of circuit board to be shipped.
By soldering some of the bottom components through the tray, it is also possible to use PCB wave soldering equipment for selective soldering of the product.
Since most trays are thick (sometimes 15 mm), solder certainly does not flow to the top of the board. The oxide layer on the solder surface will also be washed away by the edge of the tray before the board reaches the peak, so that when the solder starts, the tin is relatively clean.
By adding some stiffening strips to the tray, it can increase its hardness to withstand high-strength welding. It is also possible to install heat-absorbing blocks, component fixing devices and some other auxiliary devices on the upper part.
The use of pallets also helps standardize the width of the product line, soldering different circuit boards on the same production line, and can use bar code readers and other identification tools to quickly change process programs for different boards.
Although there are many advantages to using trays in lead-free soldering, it can also cause solder balls.
Requirements for pallet materials:
In order to maximize the service life of the trays, the trays must be made of materials that can withstand high temperatures and harsh process conditions, especially for lead-free soldering.
To meet these requirements, the material used to make the tray must meet the following characteristics:
• High dimensional stability
• Good thermal shock resistance
• Can remain flat after repeated use
• Corrosion resistance (flux and cleaning agent)
• Does not absorb moisture
The use of the tray brings the process problems:
The flux system must be able to spray the circuit board completely with flux. Poor tray designs can lead to “shadow effects” in flux spraying: Some parts of the board have insufficient flux or no flux at all. The flux must be sprayed onto the board and spread through the capillary action.
Before the tray touches the crest, it must be heated in the preheating unit. A typical preheating configuration is a combination of heat pipes and hot air forced convection. If the temperature drops before contact with the peak, the tray will have an endothermic effect, making the welding process difficult to control.
The use of trays requires a wave height of up to 0.5 inches (12.5 mm). In the case of such a high pump speed, the use of nitrogen can help reduce dross. When using pallets in lead-free soldering, Vitronics Soltec’s perturbed “smart wave” can also promote tinning of the perforated component.
In addition, we must pay special attention to keeping the circuit board in the pallet flat. If there is a gap between the circuit board and the tray, the flux will flow into the gap, and the solder will flow to the board when passing through the peak. This will cause solder residue on the board.
The gap between the circuit board and the tray may cause solder residue on the circuit board
Circuit board and tray design recommendations:
Avoid placing larger components near the piercing element as this can cause shadowing effects and tin difficulties.
Leave proper clearance around the pins and edges of the through-hole components so that solder can flow. These tin guides will guide the solder to the seat of the tray opening, while also greatly improving the solder flowability.
The tin slot at the tail of the tray allows the solder to flow smoothly back to the tin tank
The opening of the tray should be as large as possible to facilitate the flow of solder. This will reduce some of the welding defects, such as: short circuit and solder balls. At the same time, it is also beneficial to the solder filling of the through hole, because the large opening also means that there is more energy to enter the welding area.
The SMT assembly process is closely related to each process before welding, including capital input, PCB design, component weldability, assembly operation, flux selection, temperature / time control, solder and crystal structure, etc.
At present, the most commonly used solder for wave soldering is eutectic tin lead alloy: tin 63% and lead 37%. The temperature of solder in the soldering pot should be mastered at all times. The temperature should be higher than the temperature of the alloy at 183 C, and the temperature is uniform. In the past, the temperature of soldering pot at 250 degrees was regarded as “standard“.
With the innovation of flux technology, the uniformity of the solder temperature in the whole solder pot is controlled and the preheater is added. The development trend is to use the solder pot with low temperature. It is common to set solder pot temperature at 230-240 degrees Celsius. Usually, the components do not have uniform thermal quality. It is necessary to ensure that all solder joints reach enough temperature to form qualified solder joints. The important problem is to provide enough heat to raise the temperature of all leads and pads, thus ensuring fluidity of solder and wetting both sides of solder joints. The low temperature of the solder will reduce the thermal shock to the component and the substrate, and help to reduce the formation of the slag. Under the lower strength, the flux coating operation and the flux compound can make the peak of the wave with sufficient flux, thus reducing the burr and welding ball. The solder composition in the solder pot is closely related to the time, which changes with time, which leads to the formation of the scum, which is the reason for the removal of residual and other metal impurities from the welded components and the loss of tin in the welding process.
These factors can reduce the fluidity of the solder. The maximum limit of tin content in metal scum and solder should be specified in the procurement. In the welding process, the requirements for the purity of solder are also specified in the ANSI/J-STD-001B standard. In addition to the limitation of scum, the minimum content of tin in 63% tin and 37% lead alloys should be no less than 61.5%. The concentration of gold and organic swimming layer on the wave soldering assembly is faster than in the past. This aggregation, combined with obvious tin loss, can cause solder loss of fluidity and produce welding problems. Rough and granular solder joints are often caused by scum in solder. Because of the concentrated pomum in the solder pot or the innate and coarse grainy welding spot of the component itself, it may also be a sign of low tin content, not a local special solder, or the result of tin loss in the tin pot. This appearance may also be caused by vibration or shock during solidification.
The appearance of solder joints can directly reflect technological problems or material problems. In order to maintain the “full pot” state of the solder and to analyze the solder pot according to the process control plan, it is very important to analyze the solder pot. The flux in the soldering pan is usually not necessary because of the dross in the soldering pan, which is usually unnecessary, because the solder in the tin pot is required in the conventional application to make the solder in the tin pan always full. In the case of loss of tin, the addition of pure tin helps to maintain the desired concentration. In order to monitor the compounds in tin pot, routine analysis should be carried out. If tin is added, sampling and analysis should be taken to ensure the correct proportions of solder components. Too much scum is a tricky problem. There is no doubt that there are always scum in the tin pot, especially when welding in the atmosphere. The use of “chip wave peak” is very helpful for high density welded components. Because the surface of the material exposed to the atmosphere is too large to oxidize the solder, more dross will be produced. The solder is covered with a scum layer and the oxidation rate slows down. In welding, more turbulence will occur due to the turbulence and flow of the crest in the tin pot. The recommended method is to skim the scum. If skipping regularly, more scum will be generated and more solder will be consumed. Scum may also be involved in the wave crest, causing the instability or turbulence of the crest. Therefore, it is necessary to give more maintenance to the liquid components in the tin pot. If the amount of solder in the tin pot is allowed to reduce, the scum on the solder will enter the pump, which is likely to happen. Sometimes, granular solder joints are mixed with scum. The scum found initially may be caused by rough crest and may block the pump. Tin pots shall be equipped with adjustable low capacity solder sensors and alarm devices.
Crest is the core of wave crest in wave soldering process. The most critical step is to bring the preheated, coated, and non – dirt metal through the conveyor belt to the welding workstation, contact the solder with a certain temperature, and then heat it, so that the flux will produce chemical reactions, and the solder alloy forms interconnect through the wave peak power. At present, the commonly used symmetrical peak is called the main wave peak, which sets the pump speed, wave peak height, depth of infiltration, transmission angle and transmission speed, so as to provide a full range of conditions to achieve good welding characteristics. The data should be adjusted properly, and the solder should be slowed down and slowly stopped after leaving the crest. PCB with the wave crest running, the solder will be pushed to the outlet. In the most reliable case, the surface tension of solder and the optimal crest operation of the plate can achieve zero relative motion between the components and the crest of the outlet. This shelling area is achieved by removing solder from the plate. Sufficient inclination angle should be provided to avoid defects such as bridge, burr, wire drawing and solder ball. Sometimes, the outlet of the crest needs hot air flow to ensure that possible bridging is eliminated. When the surface mount element is installed at the bottom of the plate, sometimes, the bubbles in the “harsh wave peak” region formed in the back of the flux, and the wave peak is used before the wave peak is leveled. The high vertical velocity of the turbulent crest helps to ensure the contact between the solder and the lead or pad. The vibration part behind the leveling laminar peak can also be used to eliminate bubbles and ensure satisfactory contact components of the solder. The welding workstation should basically achieve: high purity solder (according to standard), wave peak temperature (230~250 degrees C), total time of contact peak (3~5 seconds), depth (50 ~ 80%) of PCB immersed in wave peak (50 ~ 80%), to achieve parallel transmission track and flux content in tin pot in parallel state of wave peak and orbit. Cooling after wave soldering is usually equipped with cooling workstations at the end of the wave soldering machine. It is a trend to restrict the formation of solder joints between copper and tin intermetallic compounds, and the other is to accelerate the cooling of the components, and to avoid the plate displacement when the solder is not fully solidified. The rapid cooling assembly is designed to limit the exposure of sensitive components to high temperatures. However, the danger of corrosive cooling system to thermal shock of components and solder joints should be taken into account. A well controlled “soft, stable” and forced gas cooling system should not damage most components. There are two reasons for using this system: it can process the board quickly without hand holding, and ensures that the temperature of the component is lower than that of the cleaning solution. People are concerned about the latter reason, which may be responsible for the foaming of some flux residues. Another phenomenon is that sometimes there is a reaction with some flux dross, so that residues can not be washed away. No formula can meet the requirements of all machines, all designs, all materials and technical material conditions and requirements that are guaranteed to meet the data set by the welding workstation. We must understand every step of the whole process. 4 conclusion in conclusion, in order to obtain the best welding quality and meet the needs of the users, every step in the pre welding and welding process must be controlled, because each step of the assembly process of SMT is interrelated and interacted with each other, and any step has the dependability and quality in the whole. Welding operation is also the case, so all parameters, time / temperature, solder volume, flux composition and transmission speed should be strictly controlled. For the defects produced in the welding, the causes should be identified early, and the corresponding measures should be taken to eliminate all the defects that affect the quality in the bud. In this way, the products produced can be guaranteed.