Quality

Our Quality Control System

We have a comprehensive quality control system, from raw materials, semi-finished products to finished products.

Material Testing
The material properties must fulfil the requirements stated in the actual material specification.
The following tests are to be carried out for cylinder liner:
1, Chemical analysis

2, Brinell hardness

3, Tensile strength analysis

Pressure Testing
The cylinder liners are to be water pressure tested.

Inspection of Surfaces
An all-over final visual inspection of the finish-machined cylinder liner must be carried-out.

Inside Running Surface Inspection
Check of the general uniformity of surface appearance including the following:
1, Macro defects: Surface defects which can easily be seen by the naked eye, such as sand and slag inclusions, larger gas holes, pin holes, shrinking porosities, etc. Defects of these types will often
appear as single defects.
2, Micro defects: Surface condition which can be observed as a coarse-to-open material structure. The defects can occur as small spots or groups of spots with coarse grained material structure.

Outside Surfaces Inspection
All over visual inspection of all outside surfaces must be carried out including:
1, Contact faces to cylinder cover and cylinder frame
2, Drilled cooling bores
3, Grooves in area of cooling bore, roundings and transitions
4, O-ring grooves, bores for cylinder lubrication, scavenge air ports etc

Quality Assurance

1, SPC automatic online monitoring for key characteristics
2, Key process capability CPK >1.67
3, Key items are 100% inspected
4, Use Poka-yoke
5, ZDM (Zero defect management)
6, Establish product traceability system. Every batch can be traced by scanning barcode and QR code

Continuous Improvement in Quality with Following Process

1, LPA: Layered process audit
2, Monthly quality meeting to make priority reduction plan
3, Quarterly Innovation and Improvement review for continuous improvement
4, Use 5W 2H analysis method to find the root cause
5, Use 8D process to carry out the quality improvement activities
6, Establish quality problem database to avoid error reoccurrence