Vol. 2, No. 8, August 2018


Critical aspects of machining process capability

for automobile spare part manufacturing (I)

The automobile spare parts we purchase typically consist of many systems based on system classifications, such as engine, chassis, braking, suspension, steering, electrical, etc. The production of parts for each system requires different techniques depending on different product applications and their technical and quality requirements. The techniques include casting, die casting, forging, welding, stamping, heat treatment, and machining, etc.

Ferrous metals are used as raw materials to produce many parts. Blanks are first manufactured with processes of forging, casting and die-casting in the early production stage. The blanks are then machined to become finished products that meet designed requirement through the machining process.

When international buyers purchase automobile parts that have been machined, they need to watch for the suppliers’ machining process capabilities from the perspective of quality management, as these capabilities are critical to ensure the parts comply with the technical and quality requirement.

We will briefly describe each of the eight key aspects of process audits: people, tooling, material, process control, environment, testing, recording and marking. For buyers with limited knowledge of machining, the information will help you make sound decisions in the qualification of your machining suppliers.

Audit focus 1: People


Have the operators gone through pre-job training and been determined to have the required skills?


Do the operators understand what the special focuses are for this process?


Do the operators know what items should be inspected and if they are able to properly use the measuring instrument for testing?


Do the operators carry out the productions, first-piece inspections and self-inspections according to the operation/inspection instructions?


Are the operators aware of the fixed item inspection requirement?


Do the operators know how to handle defective parts during productions? Are procedures available and in place?


For operators using the X-R control chart process, do they understand the applications of the control charts?

By Felix SS YUAN



The automobile clutch generally consists of active part, driven part, pressing device and operating mechanism.

According to the friction working environment, it can be divided into dry type and wet type; according to the number of driven discs, it can be divided into two types: single piece and double piece; according to the type of compression spring, it can be divided into coil spring and diaphragm spring. According to different transmission modes, it can be divided into friction clutch, hydraulic coupling and electromagnetic clutch.

Primary failure modes:

1. Incomplete clutch separation: clutch pedal stroke being over range;
2. Clutch slip:free path of the clutch pedal is too small or none;
3. Clutch shake: oil stain on the clutch, the rivet of the driven disc and hub is loose or the friction surface is uneven;
4. Abnormal sound: oil stain and dust between the clutch release bearing sleeve, or the bearing return spring and the clutch pedal return spring are fatigued, broken, falling off, etc.

Preventive measures:

1. Check the clutch pedal free path.
2. Remove the clutch, check whether the pressure plate is deformed, whether the spring tension of the compression spring is uneven, whether the moving hub and the shaft spline are loose, or whether the transmission shaft is bent.

By Y. Wang


5S & 5S Management

5S management is being talked about a lot in the automobile industry. As a workplace organization method, 5S was initially developed by Hiroyuki Hirano in Japan as part of the “Just in time manufacturing” concept.

5S comes from five Japanese words: seiri (Sort),seiton (Set in order), seiso (Shine), seiketsu (Standardize), and shitsuke (Sustain), and they describe how to organize a workspace for efficiency and effectiveness. Some manufacturers have added a sixth element, safety, to the theory, so that 5S has become 6S.

The 5S management methodology has been practiced in the Chinese manufacturing industry for many years. It not only helps improve internal operations efficiently and effectively, but also raises customers’ confidence level in the factories when they make the purchases.


Cost of raw materials:

Exchange rates:

USD/RMB: 1:6.83

EUR/RMB: 1:7.99

RUB/RMB: 1:0.10

August 2018

The above information is for reference only


Guangzhou International Auto Parts & Aftermarket Exhibition (AAG) 2018 will be held from the 3rd to 5th September 2018 in the Guangzhou World Expo, China. The exhibition will attract more than 1,600 exhibitors, as well as more than 50,000 professional visitors and buyers worldwide.

The exhibition will cover auto parts, automotive products, automobile repair, maintenance, beauty, modification, intelligent interconnections, new energy, automobile insurance, automotive finance, automotive e-commerce services and many other fields.

The official website of the fair is: 

Automechanika Frankfurt 2018 is an international trade fair for the automotive industry and the most successful trade fair concept of Messe Frankfurt as a meeting place for the industry. On the automechanika in Frankfurt visitors from crafts, workshop, retail, automotive, owner or operator meet relevant suppliers of workshop equipment and the automotive supplier industry. The fair offers a unique range of products in the areas workshop and service station equipment, auto parts, tuning, IT, car wash and more.

The official website of the fair is: 

Shentou will take part in Automechanika Frankfurt 2018 as an exhibitor and our booth numbers are Hall 1.2 -Booth A29 and Hall 10.1 - Booth C12. We look forward to meeting you there!

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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