Vol. 2, No. 12, December 2018


Critical aspects of machining process capability
for automobile spare part manufacturing (V) - Environment

When international buyers are purchasing machined parts in China, it is important to have some basic understanding of the machining process capabilities of the suppliers.

The most critical elements that assure a sound process include people, tooling, material, process control, environment, testing, recording and marking.

When you inspect or just visit your machining suppliers, the following is a list of questions you’d need to check with the supplierson “environment”,as part of the evaluation of the level of their capabilities.
1. Is the working environment neat and tidy, and are the on-site materials, products, tooling, tools, and containers clean with fixed location management?
2. Are the operators aware of the requirements for civilized production and safe production and their implementation? Are they conscious of the environment?
3. Is visual management implemented on-site?Are unprocessed/processed and qualified/unqualified parts separated?
4. In the physical-chemical / physical properties (performance) testing laboratory, are various types of reagents identified and placed in fixed locations?Do the metallographic and measuring rooms have temperature and humidity meters and the data shown meet the temperature and humidity requirements?
5. Does the working environment meet the requirements, and whether there are artificial lightings for places with poor light?
6. When the working conditions generate noise, dust, exhaust gas, sewage, flammables, explosives, and solid waste, are there disposal measures? Are there emergency response and preventive plans and measures?
7. When there are hazards conditions affecting occupational health and safety, are there sufficient site identifications with markings? Is the fire equipment intact and effective, and the passage is clear? Are there emergency response and preventive plans and measures?

By Felix SS YUAN


King Pin

The king pin is a standard metal component for connecting tractors and trailers used in semi-trailer and trailers. The commonly used forms are shown as follows, which can be divided into type 50 (2”-50mm) and 90 (3.5”-90mm) according to their diameters. It is generally made of carbon steel and alloy steel, which are machined and heat treated to obtain the corresponding hardness.

Primary failure modes for King Pin:
1. King pin and trailer beam break-off: the king pin and the trailer carriage are separated by force due to poor welding of the king pin at the trailer beam;
2. The king pin breaks: (A) Insufficient strength of the raw materials or improper heat treatment, resulting in stress concentration; (B) Trailer overload;
3. The gap between the king pin and the fifth wheel assembly is too large resulting in abnormal noise; The fifth wheel assembly or the pin body worn out due to prolonged use;
Loose connection plate of assembled king pin resulting in abnormal noise due to worn-out of the king pin and the connecting plate bolt.

Main quality control points in production:
1. Raw material incoming inspection;
2. Strict control of the processing measurement;
3. Heat treatment hardness test, required to reach HRC23-28;
4. Rust prevention treatment before packaging.

Product testing:
1. Check whether the main assembly dimensions of the components meet the requirements;
2. Visually check whether there are cracks on the surface of the product (Use detection equipment for higher requirement);
3. Check if the specifications and strength of the accessories are up to the requirements.

By Carlos WJ.Lin


FAI (First Article Inspection)

When it comes to quality control in a production process, we sometimes hear quality professionals use various abbreviations to identify some of the key quality control steps. For example FAI(First Article Inspection) is a typical one.

The automotive, along with several other industries, requires a strict compliance of manufacturing and quality assurance. First Article Inspection (FAI) is the critical part of detailed verification of production results versus product design before batch manufacturing begins. With the complete analysis for the first item created in production, the proper documentation of design characteristics, manufacturing parts, referenced exhibits, drawing requirements, and product specifications are carefully reviewed for compliance.


Cost of raw materials:
Exchange rates:

USD/RMB: 1:6.91

EUR/RMB: 1:7.82

RUB/RMB: 1:0.10

December 2018

The above information is for reference only


With the publication of the December issue of this Newsletter, we are going to say good-by to 2018. We are most grateful that you have accompanied us through the entire year and given us the encouragement and inspiration to continue the writing.

We sincerely thank you for your subscription and reading of the Newsletter in 2018, hoping the publication has helped your purchasing activities in China in some way.

Your feedback and advice are important to us, and we look forward to hearing from you. Please send emails to to share your experience of the quality issues with your China procurement or let us know what you’d like to read more in the Newsletter in 2019, we will send you a small gift to show our deep appreciations.

Happy Holidays!

SHENTOU SUPPLY CHAIN MANAGEMENT CO. LTD. is a Shenzhen, China, based company serving international automotive clients in the implementation of their China strategies and programs. CHINA AUTOMOTIVE SUPPLIER QUALITY MANAGEMENT BRIEFING is a bi-monthly newsletter published by Shentou to address the specific and unique quality challenges and concerns international automotive companies face with suppliers in China. Comments are welcome at Click here to subscribe.

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