Estimating Pickment Machine Costs refer to BOM Analysis

Estimating Placement Machine Costs refer to BOM Analysis

Since the cost of placement machines accounts for 70% of the production line, it is important to analyze the value of the machine， It can be tempting to try to cut corners in this part of the SMT assembly process, but attempts to save funds in the short-term could cost you in the long run. Some of the productivity headaches we’ve had customers tell us about when they’d tried to “go cheaper” in the past include:

Time lost to excessive changeovers or attempts to optimize setups
Failure to keep pace with output goals
A need to add costly hand assembly for parts the machine didn’t handle
Too much offline time due to service and support issues
It is, however, just as easy to overspend—on capacity, speed, or features you don’t need. The more you invest in a machine, the longer it takes for it to earn its keep. So why waste money on capability you’ll likely never use?

The sweet spot is to achieve payback within a year or so—without incurring additional unexpected costs. At Joysmt, we’ve been able to work with customers to get them a return on their investment in as little as nine months.

It all comes down to maximizing productivity while minimizing investment dollars—something that’s a lot easier to do if you do it all the time, like our team does. Of course, you can try to do it on your own or you can hire a consultant to help you, but did you know that Joysmt offers—free, with no obligation—a full-scale professional analysis of your production requirements and bills of materials (B.O.M.)? For no charge, Joysmt will custom-configure a machine to meet your exact specifications and throughput requirements. What’s more, based on your total budget, we will make recommendations for feeder types, sizes, and quantities to provide optimum performance, minimum changeover, and the quickest return on your investment.


Full-Scale Production Analysis
What does a free Joysmt Production Analysis entail? It starts with one of our experienced team members asking you basic questions about your needs. For example:

What’s the largest PCB you assemble?
What is the smallest component you need to place? How many?
The finest pitch QFP? BGA?
What is the largest component you need to place? How many?
How many different board designs do you have to build?
Are the boards single- or double-sided?
What is the maximum number of unique components on any one side of all of the boards you build?
Is there a lot of component commonality among the various board designs?
How many total component placements are there per board?
For each design, how many boards do you need to assemble per year?
What is the typical size (number of boards) of a production run?
Will your pick and place be used as an in-line machine or in a stand-alone batch configuration?
We’ll also ask you to send along the full B.O.M. for each of your products. (And we're happy to sign an NDA agreement before you send it.) You needn’t worry if your B.O.M. is in a raw format. Our team can usually identify component sizes and packaging from your most basic descriptions by means of our extensive SMD cross-reference.

Feeder capacity, combined with a feeder strategy geared toward optimizing and streamlining setup and job changes, can make the difference between a chronic headache and a smooth-running operation for manufacturers who intended to run several different jobs on a single machine.

All of this information together will help us pass along to you the following information:

The pick and place machine model(s) that will best meet your placement accuracy, range of component sizes, feeder capacity (for either batch or inline configurations), and throughput requirements (CPH)
The minimum number, types, and sizes of feeders you’ll need to build any one of your boards
The number, types, and sizes of feeders you’ll need, optimized for common components across jobs to ensure minimal changeover
Optional cameras or other accessories needed to handle ultra-small, over-sized, or odd-form components
Other accessories and recommendations that can minimize cost and maximize machine utility
Making use of decades of experience evaluating B.O.M.s and custom configuring countless pick and place machines, our equipment experts will carefully review this information with you, along with strategies for simplifying changeovers, streamlining workflow, and reducing your overall pick and place machine cost.

Joysmt provides similar free needs-analysis services for all our major production equipment, including reflow ovens, stencil printers, complete assembly lines, and wave solder machines. Whatever your equipment needs, get in touch with a Joysmt electronics assembly equipment expert today.

The latest SMT | THT Mixed Welding Technology

The latest SMT | THT Mixed Welding Technology

In conventional electronic assembly processes, wave soldering techniques are commonly used for welding of PCB-mounted board assemblies (PTH). But the wave soldering has many shortcomings: can not be distributed in the welding surface of high-density, fine pitch patch components， bridge, leakage welding more; need to spray flux; printed circuit board by the greater thermal impact warping deformation. As the current circuit assembly density is getting higher and higher, the welding surface will inevitably be distributed with high density, fine pitch patch components, the traditional wave soldering process has been powerless, generally only the first soldering surface patch components reflow soldering , And then hand-repair welding the remaining plug-in solder joints, but there is poor solder joint quality problems. In order to meet these challenges, several new types of mixed welding technology are emerging, such as selective welding, through-hole reflow and use of shielded molds, etc., can protect the surface mount components to achieve through-hole component welding, significantly reduce the production process And cycle time. This article will be introduced one by one.

Several kinds of mixed welding technology introduction
1.1 Selective welding
The process characteristics of selective welding can be understood by comparison with wave soldering. The most obvious difference between the two is that the lower part of the PCB is completely immersed in the liquid solder, and in the selective welding, only part of the specific area and solder wave contact. Since the PCB itself is an undesirable heat transfer medium, it does not heat and melt the solder joints of adjacent components and PCB areas. The flux must also be pre-applied before welding. Compared with the wave soldering, the flux is only applied to the part of the PCB to be welded, rather than the entire PCB. Selective soldering is not suitable for solder patch components.
Selective welding process has two different processes: drag welding process, dip welding process.
(1) drag welding process. The selective trapping process is done on a single small tip solder wave, as shown in Figure 1. The trailing process is suitable for very tight space on the PCB for welding. For example: individual solder joints or pins, single row of leads can be trailer welding process. The PCB moves at different speeds and angles on the solder wave of the tip to achieve optimum welding quality. To ensure the stability of the welding process, the inner diameter of the tip is less than 6 mm. After the flow of the solder solution is determined, the welds are installed and optimized in different directions for different welding needs. Robot can be from different directions, that is, 0o ~ 12o different angles close to the solder wave, so the user can weld a variety of components on the electronic components, for most devices, the proposed tilt angle of 10o.

Compared with the dip welding process, the soldering process of the solder solution and the PCB board movement, making the welding heat conversion efficiency is better than the dip welding process. However, the heat required to form the weld connection is transmitted by the solder wave, but the solder wave of the single weld is of low quality and only the temperature of the solder wave is relatively high in order to achieve the requirements of the trailing process. Example: Soldering temperature is 275 ℃ ~ 300 ℃, dragging speed of 10 mm / s ~ 25 mm / s is usually acceptable. In the welding area for nitrogen, to prevent the solder wave oxidation, solder wave to eliminate the oxidation, making the trapping process to avoid the emergence of bridge defects, the advantages of increased drag welding process stability and reliability.
The machine has the characteristics of high precision and high flexibility. The module structure design system can be customized according to the special production requirements of customers, and can be upgraded to meet the needs of future production development. The movement radius of the manipulator can cover the flux nozzles, preheat, and solder nozzles, so that the same device can perform different welding processes. Machine-specific synchronization process can greatly shorten the veneer process cycle. The ability of the robot to make this choice welding has the characteristics of high precision and high quality welding. (X, Y, Z, U, q) of the manipulator allows the PCB to be able to use any of the & lt; RTI ID = 0.0 & gt; (x & lt; / RTI & gt; Optimize the angle and orientation of the contact tin surface for optimum welding quality. Robot plywood device installed on the tin wave height stylus, made of titanium alloy, under the control of the program can be measured regularly tin height, by adjusting the speed of tin pump to control the height of tin to ensure the stability of the process.
Despite the above advantages, the single-port solder wave trawling process is also inadequate: the welding time is the longest time in the three processes of flux spraying, preheating and welding. And because the solder joint is a one of the drag welding, with the number of solder joints increases, the welding time will be a substantial increase in the welding efficiency can not be compared with the traditional wave soldering process. But the situation is changing, multi-nozzle design can maximize production. For example, double-welded nozzles can be used to double production. Flux can also be designed as a dual nozzle.
(2) dip welding process. Immersion Selective welding system has a number of solder mouth, and PCB to be solder joints are one to one design, although the flexibility is less than the robot type, but the output is equivalent to the traditional wave soldering equipment, equipment cost relative to the lower hand. According to the size of the PCB, you can carry the board or multi-board parallel transmission, all the solder joints will be completed in parallel with the same time to complete the flux spraying, preheating, and welding. However, due to the distribution of solder joints on different PCBs, so the need for the production of different PCB solder mouth. The size of the tip is as large as possible to ensure that the welding process is stable and does not affect the surrounding adjacent devices on the PCB. This is important and difficult for the design engineer because the stability of the process may depend on it.

The use of immersion selective welding process, welding 0.7 mm ~ 10 mm solder joints, short pins and small size pad welding process is more stable, the possibility of bridging is also small, adjacent solder joints, the distance between the device and the tip Should be greater than 5 mm. Select the dip welding process, you can use the following parameters:
① solder temperature 27 5 ℃ ~ 300 ℃
② immersion speed 20 mm / s ~ 25 mm / s
③ immersion time 1 s ~ 3 s
④ dip speed 2 mm / s
⑤ Shock pump rate according to the number of nozzles

1.2 through-hole reflow
In short, through-hole reflow (THR) is the use of reflow soldering technology to assemble through-hole components and special-shaped components. As the product more and more attention to miniaturization, increase functionality and improve component density, many single and double panels are based on surface mount components (SMC). However, due to inherent strength, reliability and applicability, in some cases, through-hole devices are still better than SMC, especially in the PCB edge of the connector.

The use of through-hole devices on circuit boards based on surface mount components is disadvantageous in that the cost of individual soldering points is high, as additional processing steps are involved, including wave soldering, manual soldering or other selective soldering methods. The key to this type of assembly is the ability to provide synchronous reflow for through-holes and surface mount components in a single integrated process. Figure 2 for the through-hole reflow process.

The through-hole reflow process enables reflow soldering of through-hole devices and SMC devices simultaneously in a single step. The steps required to manufacture the process depend on the special components used in the assembly. For example, the computer board has a large number of SMC (which accounts for most of the components used) and a limited number of through-hole devices: connectors, discrete components, switches and jack devices. At present, SMC is fixed on the PCB using solder paste screen printing and reflow soldering. A similar process can be used to complete the interconnection of through-holes and shaped devices. 

In many cases, the use of the THR process eliminates the need for subsequent wave soldering operations.
1.2.1 Paste coating process
Compared with the general surface mount technology, through-hole reflow process using the amount of solder paste than the average SMT more, about 30 times its. The current through-hole reflow process mainly uses two kinds of solder paste coating technology, including solder paste printing and automatic point solder paste.
(1) solder paste printing. For THR processes, screen printing is the preferred method of depositing solder pastes on PCBs. The thickness of the stencil is a key factor, which will affect the amount of solder paste that is printed on the PCB. Can be used ladder stencil, in which the thicker area for the through-hole devices and set up. This steel mesh design can meet the requirements of different amount of solder paste.

(2) automatic point solder paste. The automatic spot solder paste successfully deposits the correct solder paste for the through-hole and the profiled assembly, which provides the flexibility and the ability for a large number of solder paste deposits that can not be achieved by screen printing. It is recommended to use nozzles that are slightly larger than the PTH diameter when the solder paste is plated at the Plated Through Hole (PTH). In this way, when the solder paste is forced, the solder paste is forced against the hole wall of the PTH and the material is slightly extruded from the bottom of the PTH, and the assembly is inserted in the opposite direction from the solder paste. If a nozzle smaller than the PTH diameter is used, the solder paste will be discharged from the hole and cause severe solder paste loss.
Through-hole reflow soldering in many ways can replace the wave soldering to achieve the welding of the insert components, especially in the processing of welding surface distribution of high-density patch components (or fine pitch SMD) plug-in solder joints, then The traditional wave soldering has been powerless, and the other through-hole reflow can greatly improve the quality of welding, which is sufficient to make up for the expensive equipment. The emergence of through-hole reflow, for the rich means of welding, to improve the circuit board assembly density (in the welding surface distribution of high-density patch components), to enhance the quality of welding, reduce the process, are of great help.

1.2.2 assembly process of through-hole reflow element
The special components used in computers, automation equipment and communication equipment Because of their high height, peculiar shape and heavy weight, it is required that the automatic patch device has the ability to handle a wide range of components,
 
(2) Adjustable clamps - Some components may require special clip picking and assembly; 

(3) Special plate support and clamping Specialized suction nozzle - with sufficient vacuum suction; System; 
(4) high assembly pressure;
(5) for the special-shaped components of high-precision assembly, the machine has a full image processing capacity.
One of the reasons for the industry's renewed interest in through-hole technology is that some brands of automatic placement devices, such as Advantech AX72 and Ploaris, Universal Instruments, have a strong ability to mount shaped and through-hole components. Components can be used tube, taped, waffle plate and other packaging, feeder directly installed in the placement machine. Automatic placement with the advantages of precision, reliability and high speed, and can be automatically installed components are also more and more. Manual placement is the next level of placement option, with some through-hole connectors due to the positioning pin design that helps to align. For high-pin components, these are becoming more and more important. Manual placement is that the installation cost is low and there is no set time, the disadvantage is low speed, and the accuracy is not stable.

1.2.3 Through-hole reflow soldering process
Reflow must be able to provide sufficient heat (temperature) for the entire assembly and all pin locations. Many special / through-hole devices are higher and have larger heat capacity than other surface mount components assembled on the assembly. For THR applications, the general use of infrared radiation reflow, to avoid hot air convection temperature uneven impact on welding. Separate top and bottom heating controls also help to reduce the temperature difference on the PCB assembly. For computer motherboards with a high stack of 25-pin DSUB connectors, the component body temperature is unacceptably high. The solution to this problem is to increase the bottom temperature and lower the top temperature. The time on the liquidus should be long enough to allow the flux to volatilize from PTH, which may be longer than the standard temperature curve. Sectional analysis may be important to confirm the correctness of the reflow profile. In addition, the peak temperature and thermal gradients on the components must be carefully measured and strictly controlled. (2) the distribution of temperature on the monitoring board, the temperature difference between the size of the components; (3) consider the thermal compatibility of the component body; (4) the heating rate , Liquid phase above time, reflux peak temperature, cooling rate.
The appropriate stable heating rate is required because, during this process, the viscosity of the solder paste is maintained due to the decrease in the viscosity of the solder paste and the viscosity of the solder paste is increased by the volatilization of the flux. It is important that the top of the component pins leave solder paste.
1.3 use shielded mold wave soldering technology
As a result of the traditional wave soldering technology can not cope with the welding surface fine pitch, high-density patch components of the welding, so a new method came into being: the use of shielding mold (Figure 3) masking patch components to achieve the welding surface of the plug Wave soldering.

1.3.1 Advantages of using shielded die wave soldering technology
1) to achieve double-sided mixed PCB wave soldering production, can significantly improve the double-sided mixed PCB production efficiency, to avoid the existence of manual welding quality consistency of the problem.
2) to reduce the paste solder paste preparation time, improve production efficiency and reduce production costs.

3) Production is equivalent to traditional wave soldering.

1.3.2 shield mold material
1) production mold must be anti-static, common materials: aluminum alloy, synthetic stone (domestic / imported), fiberboard. When using synthetic stone to avoid wave soldering sensor is not sensitive, it is recommended not to use black synthetic stone.
2) Make mold base material thickness. According to the thickness of the reverse plate components, select 5 mm ~ 8 mm thickness of the substrate making mold.

1.3.3 Mold process size requirements
1) Dimension of the mold: The length and width of the mold are equal to the length and width of the PCB, respectively, plus 60 mm of the width of the carrier side
And the mold width must be ≦ 350 mm, the specific process size shown in Figure 4. When the PCB width is less than 140 mm, consider placing two PCBs in a mold at the same time.
2) Edge of the process edge of 8 mm, the other side close to the edge of the installation of 10 mm wide, 10 mm high electric wood to increase the strength of the mold to reduce the deformation of the mold.
3) Each reinforced stapler must be screwed and must be between 150 mm and less.
4) After the mold is finished, it is necessary to install the buckle (fixed PCB on the mold) within 100 mm and within 100 mm. Note the following: ① Do not touch the parts for one week; ② Do not affect the DIP plug PCB can be solid in the mold.

5) the four corners of the mold to open a chamfer of R5.
6) PCBA on the mold in the tin furnace, some parts by the impact of tin waves will produce floating high, so some easy to float parts of the method used to solve the problem. At present the main way: ① metal iron block pieces; ② mold on the installation of pressure buckle pieces; ③ production of anti-floating high-pressure pieces of governance.

2 concluding remarks
As the current circuit board more and more complex, the traditional wave soldering technology has been greatly limited, especially for the welding surface distribution of high-density patch components (or fine pitch SMD) plug-in solder joints, if the manual welding There is a problem that the solder joint has poor quality consistency. The best solution to this challenge is to use the new hybrid welding technology described above, which protects the surface mount components from welding of through-hole components. Choose which welding technology depends on the characteristics of the product may be, if the product batch is small, variety, you can consider the selective drag welding process technology, no need to create a special mold, but the equipment investment. If the product type is single, large batch, and want to be compatible with the traditional wave soldering process, you can consider the use of shielded mold wave soldering technology can be achieved

Selective wave soldering defects and prevention

Selective wave soldering defects and prevention

Defects and prevention, the current impact of the main problem of welding process is lead to lead-free welding conversion and miniaturization trend. Micro-welding refers to a printed circuit board with more SMD components. Processing of solder joint welding technology includes more reflow applications. The assembled through-hole components should be automatically welded to ensure optimum quality. The connection of the components and the electronic board depends on the number of solder joints, but for most products, selective welding is the best way to replace the pallet type wave soldering or manual welding.

Welding technology is now very skilled, but still has a typical flaw. Only locally available lead-free solders have a high melting point and require a higher operating temperature, which increases the risk of certain defects, including the following:
Stripping of solder joints Tail  Tin bridge  Solder ball  Copper pad dissolves

High temperature to the flux to bring no small challenge. Too little flux may cause welding defects such as Weld, and too much will cause electron migration due to residual flux. This paper will discuss these typical flaws and describe how to optimize process parameters to prevent defects.
Solder stripping
Pad stripping, solder joint peeling and solder tear tearing are due to differences in thermal expansion coefficients between PCB substrates such as epoxy / glass FR-4 laminates and copper copper copper on PCBs. In the contact with the solder process, the circuit board Z direction of the thermal expansion will be relatively large. This expansion causes the pad to become conical. This is because the thermal expansion coefficient of epoxy resin is much larger than copper through hole and line. The circuit board continues to expand even if the solder joint has been chosen by selecting the solder wave or immersed in the solder in the nozzle, since most of the heat of curing has reached the adjacent sheet.
After the circuit board leaves the solder, the heat transfer on the solder assembly to the connection is stopped and the connection is cooled to room temperature. At this stage, the heat of curing spreads into the solder zone (see Figure 1), increasing the temperature of all parts on and around the solder joints. When all the curing energy is completely released, the solder joint temperature gradually drops to room temperature. Then the solder joints begin to cure, the circuit board cools and restores its original planar shape. This movement causes considerable pressure on the surface of the solder joint, which is still not strong at this stage. Therefore, this pressure may cause the pad to float. In addition, if the adhesion between the pad and the circuit board than the solder and electronic board adhesion, it will lead to solder surface rupture, which is known as the welding foot tear.
Solder stripping is specifically described in IPC-A-610D5.2.10. Accepts the release of the bottom of the solder from the top of the main surface (weld surface) of the plated through-hole connector. In general, it is difficult to eliminate these shortcomings. But it can be improved by selecting a suitable Z-axis expansion coefficient such as a suitable circuit board material, reducing the pad size of the plated via hole or printing solder resist on the pad.

At this stage, the heat of curing spreads into the solder zone (see Figure 1) increasing the temperature of all parts on and near the solder joints.
Tailing
The next flaw problem is mainly to optimize the multi-peak soldering process by reducing trailing. The wire is a solder residue only outside the nozzle area, and its profile is related to the edge of the nozzle. These residues are generally caused by solder collapse. These lines contain different shapes of solder particles, such as different sizes of oxidized solder webs and solder balls, but these particles are mostly very small. Use the right amount of flux to completely cover the nozzle area to remove the tailing of the multimodal nozzle. In the absence of flux, the solder on the solder can also cause tailing.

 Effect of parameters on trailing. Only the welding temperature (the lower the better) and the amount of flux (the more the better) has a significant impact on the tail.
Perform a large-scale Taguchi experiment (L16 vs. 9 different parameters) to find the parameters that affect the trailing. Experiments show that only two parameters, solder temperature and flux, have a significant effect on tailing. So when there is a smear, you should try to adjust the amount of flux. In addition, applying more flux at the outer edge of the nozzle helps to reduce the solder temperature. With SnPB, the solder temperature can be reduced to 260 ° C. The post-drop temperature is sufficient to complete the through-hole filling.

Tail; solder residue only around the nozzle area
Tin bridge
Tin bridges exhibit different phenomena in selective welding (drag welding) and multi-wave soldering (dual in-line package) processes. In the process of drag welding, stable solder flow is essential. The solder flows out of the assembly in the opposite direction. When the solder begins to flow to the back (along the board), the tin bridge appears. The hot nitrogen scraper forces the solder to reverse flow and eliminates the tin bridge.
If the solder begins to flow along the pin, as shown in Figure 4, the PIN pin will leave the nozzle away from the solder. At this time, the solder will cool and cure to form a tin bridge. Horizontal welding can reduce the risk of unstable solder flow.

Unstable solder flow. Lead-free solder has a tendency to deviate from the nozzle and flow along the pin.
In a dual in-line package process, tin bridges can be avoided if designed properly. The pin is shorter, the pad is smaller, the gap between the PIN feet can reduce the risk of forming the tin bridge. Taguchi experiments show the effects of machine parameters. 10 mg / cm 2; or more flux and lower solder temperature are the best combination to prevent the formation of tin bridges. In addition, experiments show that the preheating temperature has little effect on selective soldering when the thermal mass of the circuit board is not high. Dual in-line package time is short, the lowest slowdown in solder output.

Solder ball
The solder balls are mainly due to high temperature and become more viscous solder resist. In addition, fluxes are more likely to produce solder balls than other materials. In a dual in-line package process, solder balls typically appear between the individual pins, such as Figure 6, where the solder balls appear around the tin bridge.

 In the weld zone, the tin bridge between the four pins is surrounded by a large number of solder balls.
Copper pad dissolves
The higher the welding temperature, so that copper is dissolved into the risk of solder. As the lead-free solder tin content more, at high temperatures, the circuit board on the rapid dissolution of copper speed. In the choice of solder peaks, the flow of solder to form solder joints, this process is much more important than the double in-line packaging process. The more frequent the contact (robot speed 1mm / sec or slower), the higher the welding temperature (> 300 ºC), the greater the risk. In addition to the appropriate parameters for the machine, thick copper layer is also very important, but also because of this, should be checked every two months, a copper content of solder to ensure that copper content can not exceed 1%; otherwise the reliability of solder joints will be large discount.

The assembly process, the temperature reached 320 ℃, the copper pad on all the copper are dissolved into solder.
To sum up
Select the appropriate parameters, selective welding can be successfully used. Due to the need for high temperatures, other welding processes into lead-free soldering are a considerable challenge. The biggest advantage of the selective soldering process is its flexibility to optimize each component. If necessary, it is possible to apply more flux for each infiltrated element, for longer periods of time, and to damage other components around it because of the high temperature.

Soldering fume in electronics manufacturing - damaging effects and solutions for removal

Soldering fume in electronics manufacturing - damaging effects and solutions for removal

Modern electronics manufacturing is made up by a multiplicity of different separation and joining processes, with the later surely taking the vast majority of production technology. Alongside gluing, welding and laser processes, soldering still holds a primary position in electronic assemblies. However, soldering does not always equal soldering, because there are quite a lot of different soldering technologies. Accordingly, you have to distinguish between automated and manual soldering procedures.

No matter which soldering process you analyse, all of them have one aspect in common: they produce airborne pollutants, which may have a negative impact on employees, plants and products as well.

Soldering procedures in electronics manufacturing

There are a variety of soldering procedures, but not all of them are used in electronics manufacture. Common soldering techniques in assembly production are:

1）Wave soldering or flow soldering

2）Reflow soldering

3）Dip soldering

4）Hot air soldering

5）Selective soldering

6）Laser soldering

7）Vacuum soldering

8）Vapour phase soldering

In the production of electronic assemblies, almost only soft soldering is used. The melting temperature of the solder is lower than the melting temperature of the elements to be joined, e.g. component leads to PCB pads - (approx. 180 to 260 °C). The molten solder flows between the metal parts. The objective is to create a firm, airtight, corrosion-resistant, electrically and thermally conductive interconnection. The solder is mostly designed from alloys in the form of solder wire, solder bar or solder paste. Depending on the scope of application of the final product, these alloys are composed of tin, lead, antimony, silver and/or copper. In the solder, fluxing agents can be contained, which are compiled from different chemical Hand soldering at manual workplaces is still found in the vast majority of assembly production plants. The main application area is for pre-production runs, prototyping and repair.

Released airborne pollutants

Depending on areas of application of the finished assembly and requirements of the components, various soldering alloys and flux agents are considered. During the soldering process, large parts of the flux agent and a small portion of the solder will evaporate. The emerging aerosols and particles could be released into ambient air. This will not only spread unpleasant odours, but these airborne pollutants can lead to serious medical conditions. Particularly dangerous substances are aldehydes, which emerge from materials containing colophony; some of them may be carcinogenic.

In addition, gases are released from coatings, adhesives or substrates during heating of the assembly.

These gases also transport sticky aerosols, which build up in the soldering machines or – even worse – on the products and contaminate them. This leads to increased cleaning and maintenance costs, and the operability of the plant can be impaired. In addition, the manufactured products may even be corroded by the contaminations, which could affect functionality and quality.

In conventional wave soldering processes, the entire printed circuit board is fluxed. The emerging spray mists from alcohol-based flux and other evaporations may lead to explosive, highly flammable vapour/air mixtures.

Differentiation and legal regulations

Airborne pollutants are classified according to particle size. This classification is set primarily by the influence of the emissions on the human organism. Thus, airborne

pollutants are not only differentiated, whether they are brain, nerve or airway damaging. A distinction is made, whether they are inhalable (I-fraction) or alveolar (A-fraction). Pollutants of the A-fraction overcome the so-called lung-blood barrier, which separates air-filled cavities of the pulmonary alveolus from blood in the capillaries.

Therefore, the DIN EN 481 defines statutory limit values. According to technical rules for hazardous substances in various countries, there are limit values and legal regulations that determine the utilization of extraction and filtration technology to meet these regularities.

In order to eliminate developing air pollutants, it is not sufficient to provide for only good ventilation in the manufacturing environment. The use of efficient extraction and filtration technology is mandatory and required by the Employer’s Liability

Insurance Association.

The variety of the available extraction and filtration systems is high. The selection of the appropriate system depends on type and volume of pollution, the use in automated, semi-automated or manual production environments and on mobility as well as flexibility.

State of the art extraction and filtration units achieve such a high cleaning rate for the processing air that the cleaned air can even be re-circulated into the work area.

The competitive pressure in electronics manufacturing is tremendous. Only those who provide high quality products, minimise maintenance costs and rely on healthy employees, will successfully survive in highly competitive markets. Thereby air purification plays a major role.

In the field of electronic assemblies manufacture, this means more than ventilation and vacuum cleaning. Besides removing dirt and unpleasant odours, it is mainly about removing airborne hazardous substances, which may have a drastic impact on humans, machinery and products. Effectively running extraction and filtration units help entire enterprises to maintain competitiveness.

How Many Feeder Slots Will You Need?

How Many Feeder Slots Will You Need?

Feeder slots can be one of the most confusing aspects of pick and place machines. A machine that has 64 
feeder slots won’t necessarily hold 64 feeders. Feeder slots are designed for 8-mm tape feeders. If you 
have larger tape feeders and/or sticks and waffle trays, each feeder will take up two or more feeder slots.

To determine whether a machine has enough capacity for your requirements, you will need to calculate 
just how many 8-mm feeder slots you’ll need.

Tape Feeders Slot Requirements
To calculate your feeder slot requirements, first list how many of each tape feeder size you will need. 
Then multiply each of those by the number of feeder slots the pick & place manufacturer says each will require.

Tape Feeder Example
For example, if you need 44 8-mm tape feeders and the manufacturer specifications say that each 8-mm 
tape feeder requires one feeder slot, you will need 44 feeder slots for your 8-mm tape feeders.
If you also need two 12-mm feeders, and the manufacturer’s specs say that 12-mm tape feeders require 
two slots each, you will need an additional four 8-mm tape slots (2 feeders x 2 slots/feeder) for your 
12-mm feeders, bringing your total slot requirement to 48.



Stick/Tube Feeder Slot Requirements
Generally, each manufacturer’s stick feeder will hold multiple sticks or tubes, so you’ll first figure 
out how many sticks or tubes of components you’ll have, then figure out how many stick feeders you’ll 
need in order to accommodate them, based on the number of lanes a stick feeder from that manufacturer 
holds. Finally, calculate out how many slots in the feeder base your stick feeder(s) will take up.

Stick Feeder Example
If you have 4 sticks and the available stick feeder holds 10 sticks, you would need one stick feeder. If 
the stick feeder requires 9 slots, your total slot requirement, building on the tape feeder example 
above, is now 57.

Matrix Trays and Cut Strip Tape Holders
Matrix tray holders and cut strip tape holders are sometimes mounted in feeder slots and sometimes 
placed in the board area. If the tray holder for the machine you’re looking at takes up feeder slots, 
you’ll need to find out how many and add that your requirement.
If, on the other hand, the matrix tray holder goes in the placement area, this will affect the size of 
the PCB/panel that the machine can handle, so be sure to keep that in mind.