May03
Trouble Shooting Guide for Plastic Injection

post on May 3, 2016
Trouble Suggested Remedies (Solutions)
DIMENSIONAL PROBLEMS
Shot-to-shot dimensional variations
  • Increase injection pressure
  • Maintain uniform pad (cushion)
  • Repair leaking back flow value if pad cannot be maintained
  • Increase screw forward time
  • Maintain uniform cycle
  • Eliminate un-melted particles (see below)
  • Use larger machine or screw designed for DELRIN
Warping
彎曲變形
  • Balance mold temperature
  • Decrease mold temperature
  • Increase/decrease screw forward time
  • Increase/decrease injection pressure
  • Clean water channels in mold; improve mold cooling system
  • Improve part design
  • Change or add ejector pin locations

read more…》

Plastic, Quality     WorkingBear    Views (4,987)     comment (0)

Apr07
Solution to Prevent Component Drops During Second Time Reflow Soldering

post on April 7, 2016

Solution to the Drop of First-Side Part during the Second Reflow Soldering

Due to the rapid growth of mobile phone technology, the Electronic Manufacturing Service (EMS) in mainland China sometimes faces serious labor shortages. Additionally, Industry 4.0 promotes the need for factory automation in EMS. As a result, certain parts that cannot undergo SMT reflow process must fulfill the Paste-In-Hole (PIH) process, including type-A USB connectors, Ethernet connectors, power supply sockets, transformers, and others. Previously, most of these devices were touch-up soldered after SMT processing.

read more…》

Design, Manufacture, SMT, Soldering     WorkingBear    Views (7,858)     comment (0)
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Mar09
What Process Impact of Substituting SMDs with Paste-In-Hole components?

post on March 9, 2016

SMD PIHOne day, my manager asked me a question: “Will changing the components from SMDs (Surface Mount Devices) to THDs (Through Hole Devices) and using the PIH (Paste-In-Hole) process affect the process and design?”

I later realized that the question aimed to prevent damage to connector components due to customers using excessive force.

Sometimes, Paste-In-Hole (PIH) is also referred to as Pin-In-Paste (PIP).

First, when considering traditional components inserted using the PIH process, there are several design considerations:

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Manufacture, SMT, Soldering     WorkingBear    Views (6,686)     comment (0)
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Feb01
Solder Preforms – Another Choice for Solder Volume Increasing Solution

post on February 1, 2016

Today, most of electronic components are developed into smaller size. The small chips are downsized from 1206 to 0805, 0603, 0402, 0201, even to 01005. The size of chip is smaller; the required solder volume is less.

Moreover, the required stencil thickness becomes thinner from 0.18mm to 0.10mm or 0.08mm. Some components, however, cannot be downsized unlimitedly, such as external connectors. For example, a line socket of telephone, a network line socket, a smart card reader, and other devices require a certain amount volume of solder to ensure the soldering strength and quality. In addition, some traditional insertion parts (THD, Through Hole Devices) with paste-in-hole process require extra solder volume as well.

read more…》

Manufacture, SMT, Soldering     WorkingBear    Views (9,031)     comment (0)
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Jan04
What is Step-up & Step-down Stencil? Selective Solder Paste Volume Increasing Solution

post on January 4, 2016

Step_down_stencilThe trend in the electronics industry is toward smaller and smaller SMD components, with sizes such as 0402, 0201, and even 01005 becoming common (Note 1). Additionally, the pitch between pins on ICs has decreased to a fine pitch of 0.5mm, and even 0.3mm, posing a challenge for the SMT process.

SMT engineers face the challenge of soldering these thin electronic components onto PCBs without encountering non-wetting or soldering short issues. This task is more difficult when dealing with a mix of larger and smaller parts on a circuit board.

read more…》

Manufacture, SMT, Soldering     WorkingBear    Views (17,370)     comment (0)
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