SMT Technology-SMT Equipment Facilitator

Monday, December 4, 2017

How to Produce the Best Circuit Boards|SMT Technology

Professionally assembling circuit boards used to be slow. Many circuit board manufacturers still take up to two weeks or longer to produce circuit boards according to customer design specifications.

Modern processes and efficiency‐oriented procurement can shorten that time to three to five days on average. A reputable PCB prototyping firm needs to excel at quickly delivering reliable, high quality circuit boards to clients. Investing in the efficiency and speed of the assembly floor and continually improving processes produces better, more dependable results faster.

Factory Floor Optimization Generates Product Innovation

Manufacturing and assembly floor plans for PCB prototyping can run anywhere from 5,000 to 15,000 square feet, depending on expected production volume. However, a larger manufacturing space doesn't always mean faster or better results. A PCB manufacturing space needs to be optimized for the quick production of printed circuit boards, flexible circuit boards, and rigid‐flex circuits. The only way for a PCB manufacturer to do this is by investing in state‐of‐the‐art technology on each level of the manufacturing and assembly process. The goal is creating prototype circuits according to client specifications without cutting corners.

This focus – on a fully efficient manufacturing floor – is one of the most important ways to produce value when dealing with a product as omnipresent as the printed circuit board. This is a highly engineered item. Nearly every type of product efficiency that can be integrated into a circuit board technology is already present in the client‐provided spec sheet.

In order to increase the efficiency an already highly‐engineered product can offer, PCB firms must look at the manufacturing process and eliminate waste during assembly and manufacturing.

PCB manufacturing firms that organize their assembly processes in this way are able to deliver world‐class assembly solutions to clients in a fraction of the time it takes competitors to do the same.

On a highly organized factory floor, technicians keep orders on the move continuously. Every project follows a strict and highly organized schedule, from the moment specialists begin consulting with a client, to the day the final deliverable arrives. An efficiency‐oriented team of printed circuit board veterans will make this possible through personal flexibility and a wide‐ranging breadth of knowledge in the circuit board industry.

How to Achieve a Single‐Day Turnaround

Efficient PCB prototype firms are able to efficiently prioritize jobs for clients who are in a rush. Only a few are capable of combining a commitment to only assembling the highest

quality circuit boards with an extensive range of specialty equipment for the purpose, maximizing efficiency.

Choose a manufacturer who has performed single‐day turnarounds for clients in the past. A company with a good track record for quick turnarounds will remain well‐positioned to put a new client's needs first when the occasion calls for it. From automated cable assembly to hand assembly for small‐volume projects, find the service provider uniquely positioned to solve client problems with speed and professionalism throughout the entirety of your project.

Modular Planning Eliminates Corner‐Cutting

The biggest problems that circuit board manufacturers often face are caused by generalized assembly processes. The typical assembly floor will feature a small variety of computerized workstations designed to specifically couple systems. These systems are connected by a feeder carrier – essentially a specialized conveyor belt that takes assembly products from one system to the next.

This is an ideal system to manufacture similar items in a highly automated manner, but it breaks down when creating customized solutions for clients who need fast, reliable prototypes made.

A better, more flexible system must be modular in nature. Such a system can shift and prioritize production workstations according to their greatest utility in order to maximize efficiency across the board. Even traditionally coupled systems can be improved in this manner. As product x goes from workstation A to B to C, additional production routes can be implemented at each stage.

In this way, individual workstations can be arranged as needed for a specific project and then rearranged for different projects without losing time. This is what allows PCB assembly experts to create many different types of printed circuit boards while remaining on time and within budget for each project.

Power Design Services is a San Jose‐based assembler of printed circuit boards for innovative technology products. We offer fast turnaround times on all of our projects – contact us for a quote on your prototype!

Solder Paste Printing – the Most Critical Part of Building a Quality PCB Explained

If someone were to ask what the most important part of their favorite electronic device is, they are likely to point to the printed circuit board (PCB) responsible for making the device work before moving on to other components. From large motherboards to tiny chips, most of the technology that retail consumers take for granted comes down to a properly installed and calibrated PCB.

While there are a great deal of steps in the PCB assembly process, and each is extreme importance, one stands out among all the others as being the most critical for ensuring lasting success. Incorporating surface‐mounted devices (SMDs) onto PCBS is the most critical part of a building a quality electronics product, and for good reason.

Attaching Devices to PCBs – Solder Paste Printing

One of the most popular and reliable ways to attach SMDs to boards is using a process called solder paste printing. Essentially, a screen printing device uses a stencil of the finished boards components to apply solder paste to the board with extreme precision.

Solder paste is exactly what it sounds like – a blended mix of flux medium and graded particles of solder powder. It serves as the attachment medium between the device's interconnection sites and the PCB itself.

After a PCB has solder paste accurately layered over it, PCB assemblers can reflow the solder paste – melt it at a specific temperature – to form a tight, conductive bond.

In many ways, this process is similar to screen printing graphics or designs onto textiles. The main difference is the level of precision required – both the amount and consistency of the solder paste must adhere to strictly observed standards in order to create a durable bond.

Facing Challenges with Solder Paste Printing PCBs

There are many challenges to consistently solder paste printing PCBs. Less‐than‐professional PCB assembly companies will often introduce errors during this delicate process – especially when rushing to complete large orders with tight deadlines.

In order for the process to be successful, PCB assemblers must respect several principles:

Create a Perfect Stencil: The accuracy of the process depends on the accuracy of the stencil. A shoddy, imprecise, or poorly printed stencil will never produce reliable results.

Program the Screen Printer Properly: Solder paste screen printing devices need exact measurements and calibration to perform their work with precision. Expert screen printing programming is a valuable skill in the PCB industry.

Apply the Right Amount of Solder Paste: Too much solder paste will create an imperfect outline, while a lack of solder paste will prevent the SMDs from sticking.

Choose the Right Process: There are two main methods to achieving a good print – mesh screen printing and metal screen printing. While the former is the cheapest method, it does not work on small SMDs that require precision attachment.

By paying close attention the solder paste printing process, you can accurately gauge just how capable a PCB assembly company truly is. Think of this process as the tell‐tale sign of a professional approach.

SMT nozzle selection should follow what kind of principle?

When the installation smt nozzle should follow some principle, for the universal SMT nozzle how to choose.

There are several options for the component database to be installed.
Select more than we need to be analyzed to determine the actual situation, then we use the default nozzle is good or give more nozzles, of course, only gives a benefit, that is the head of the nozzle is easy arrange, it is easy when the optimizer, but everything has its pros and cons, in this regard, there is necessarily good in some other respects there is a downside, which is like saying we are doing the math proofs when the results of the more constraints given in the title is the last to get more precise. in the end it is not the case, it is estimated that no one can give an accurate answer, because the choice of nozzle affected many aspects.

SMT nozzle selection factors used to consider the size of the object, shape and so on.
The machine default and artificial choice, the former is not the latter flexible, and no the latter closer to the actual machine only according to the size of the parts to select the nozzle.For example, some parts are very light we can choose when the small , but the machine is not, it sets a bit larger than the nozzle, often does not agree with the default and the machine element appears as if the hole in the middle or even more strip like to purchase this material for non-standard Custom model nozzle.

SMT nozzle in the selection of the time there will be optimization of this factor exists, according to the selected NOZZLE reasonable arrangement of material level, this is very important.We can set in the component databese in order to reduce the optimization cycle.If the material level is not arranged Well, it will report the X-axis limit error, we should try to put a small material on the Track1, this should be considered should not be reported X-axis beyond the reduce error.
In short, the models of the SMT nozzle in the selection should be based on the actual material by the technicial to determine the judge.

How to choose SMT consumable material ?

In the solder, it is an indispensable auxiliary material, its role is extremely important.

1) Dissolving the oxide film on the surface of the substrate to be welded In the atmosphere, the surface of the substrate to be bonded is always covered with an oxide film having a thickness of about 2 × 10-9 to 2 × 10-8 m. In the welding, the oxide film will inevitably prevent the solder on the base metal wetting, welding can not be normal, it must be coated on the surface of the base metal flux, so that the surface of the parent metal oxide reduction, so as to achieve the purpose of eliminating the oxide film.

2) to prevent the re-oxidation of the base metal material in the welding process needs to be heated, high temperature metal surface will accelerate oxidation, so the liquid flux covering the base metal and solder surface to prevent oxidation.

3) Reduce the surface tension of the molten solder The surface of the molten solder has a certain tension, as the rain falls on the lotus leaf, because the liquid surface tension will immediately coalescence into a ball of water droplets. The surface tension of the molten solder will prevent it from flowing to the surface of the base metal, affecting the normal operation of the wetting. When the flux is covered on the surface of the molten solder, the surface tension of the liquid solder can be reduced and the wettability is significantly improved.

4) to protect the role of welding the surface of the base metal was welding material in the welding process has destroyed the original surface protective layer. Good flux after welding, and quickly return to the role of protection welding consumables.

The role of solder paste paste:
In the electronic process SMT process, the main role of solder paste is bonding SMD material in the PCB should be the location of the pad to ensure that SMD SMD material will not be scattered patch. At the same time, after hot air reflow soldering and then play a fixed SMD material and connected circuit of the important role. Choose high-quality solder paste, the use of solder paste mixer to stir evenly, the use of automatic, semi-automatic or manual solder paste printing equipment to paste the quality of the printing process in the PCB on the pad. AOI (automatic optical inspection machine) check the printing paste should be completely covered PCB pad, printing thickness should be equal to the thickness of steel mesh, clear resolution, good mold release. Otherwise, the cleaning, cleaning, re-printing, solder paste printing quality directly affect the quality of solder material welding quality, the quality of welding directly affect the reliability of the product, so throughout the production process, is generally set to key Process. Therefore, in the machinery and equipment, the use of tools, materials, selection, personnel skills, methods of operation, environmental conditions must meet the process requirements, in order to achieve high efficiency, good quality purposes.

Paste is divided into: a solder paste and lead-free solder paste, lead-free solder paste that is environmentally friendly solder paste
SMT chip production The role of steel mesh: steel mesh used to semi-liquid semi-solid state of the tin paste to the pcb board, the current popular circuit board in addition to the power board outside the use of surface mount SMT technology, the pcb board There are a lot of surface-mount pad, that is, no kind of over-hole, and steel mesh hole is just the corresponding PCB board pad, hand brush tin with a horizontal hard brush to semi-liquid semi-solid state of tin slurry through steel Online hole brush to the PCB board, and then through the placement machine up to paste components, and then after the reflow soldering.

Steel mesh is divided into three kinds: laser steel mesh, etching steel mesh, polished steel mesh
SMT soldering iron role: electric iron is the electronic production and electrical maintenance essential to the main tool, the main purpose is the welding element and wire, according to the structure can be divided into internal heat soldering iron and external electric soldering iron, according to the function can be divided For the soldering iron and tin soldering iron soldering iron, according to the use of different is divided into high-power electric soldering iron and low-power electric soldering iron. The internal heat-type electric soldering iron is small and inexpensive. General electronic production with 20W-30W of the internal heating electric iron. Of course, there is a 50W external thermal soldering iron can be prepared. The electric heating of the electric iron is higher, and the replacement of the tip is also more convenient.

How to select Samsung SMT nozzle model and precautions！

1. Select the diameter of the nozzle hole can not be larger than the minimum size of the component
2. The diameter of the selected nozzle hole can not be much smaller than the minimum size of the component,
the general ratio of 1: 1.2-1.7, the closest to the minimum size of the component is better.

Such as component length:
3.2mm, width 2.0mm element, according to the minimum size of the nozzle diameter is closest to the

selection of the nozzle, so choose the nozzle CN140 is the best:
3.2mm
2.0mm

From the Samsung Mounter nozzle type can be seen on the nozzle of the corresponding size of the model,

so it is not difficult to choose the corresponding components.CN020, CN030 is mainly used to play
0201,0402 components, CN040: 0402,0603, CN065 with the mostextensive,
0402,0603,0805,1206, CN140: 1206,
Diode, transistor can be used, CN140 CN220 CN400 CN750 CN110
These nozzles are used to fight IC, the specific fight what IC, but also according to the size.

The following is the Samsung nozzle and electronic components of the reference table:

SMT placement machine odd Nozzle

What is SMT odd nozzle? In the daily SMT machining operation, the vast majority of materials can be used to absorb the conventional smt nozzle, but sometimes encountered some unconventional materials, the conventional nozzle is not suck up, or the throwing rate is very high, in this case need to be based on the size and shape of materials to customize the odd nozzle.

Advantages of odd nozzle:
1. Tailored to the size of the material size, improve production efficiency.

2. Some of the material surface is a sticky, ordinary material nozzle can not normally take the material, this situation we can according to the specificity of the material to choose the nozzle head material, in order to meet the production needs.

3. High precision, some of the material on the nozzle of the relatively high precision requirements, if the accuracy can not be guaranteed, the throwing rate will be high, we use the Japanese imports of precision machine tools, each batch of nozzle will be attached to the shipment Cargo inspection report, in order to ensure the quality of the nozzle.

How to improve SMT nozzles useful life?

How can SMT nozzles improve useful life?

First of all can be sure that the quality of the nozzle is very important,

In addition to the daily maintenance and maintenance is also very important,

the following by Joysmt to share with you smt nozzle maintenance of the general method:

1. SMT nozzle surface with a clean cloth rubbed.
2. Small aperture nozzle can be fine wire through, and then blow the air gun.
3. The surface of the nozzle can not be soaked with alcohol and other corrosive solution,

otherwise it will make the surface off.
4. HOLDER wipe with a cotton swab cavity, can not pass bad filter.
5. HOLDER minions regularly add special grease.
6. According to the best production of regular maintenance, usually do other maintenance.