Wai Kar Industrial Co., Ltd. belongs to WKK group, a joint-venture enterprise registered in Hong Kong ; which is experienced in and qualified for designing and manufacturing various kinds of high pressure gas cylinders in China, especially of type-1 and type-2.

We have accumulated the abundant design and experience of high pressure cylinder and we have a group of experienced engineers and technicians. With our strong range of diameters (from 200 to 425 mm and more), capacities (up to 300 litre) and working pressures (up to 300 bar and more). 

 WKK’s cylinders have two character:

high quality, due to the space technology.

Large diameter, from 200mm to 425mm.

WKK cylinders are suitable to the widest range of applications in all the sectors of industrial with their light weight and comprehensive range of safety and standards approvals in China. WKK can supply its cylinders in a wide range of neck threads, multicolor paint finishes based on customers’ requirements.

WKK always keeps“ Advanced Technology, Super Quality, Excellent Service” as principle to serve customers over the world.

Brief Description of WKK CNG Cylinder:

1. The materials (steel, fibres, etc.)of WKK’s cylinders are carefully selected depending on their eventual use conditions, after verifying the chemical, physical, mechanical characteristics and, where necessary, their stress-corrosion resistance.

2. The fracture mechanics analysis of the steel allows us to define the maximum permissible defects in the cylinders, in order to enable us:
-to establish the non-destructive tests in the production line
- to guarantee the product fatigue life
- to demonstrate that a leak precedes the hypothetical burst of the cylinder.

3. - The cylinders' surface protection is considered to be a function of the various environmental conditions of use and of the various corrosion agents.

4 - WKK cylinders are manufactured according to a quality control program certified to ISO9001,ISO11439

Production tests

During production all the cylinders are subject to:
   - Hardness test
    - Ultrasonic inspection
    - Hydraulic (proof and volumetric expansion) tests
    - Leak test on spun cylinders
   -Check of the critical dimensions and of the threads
    - Check of the marking
    - Check of the specified internal and external surface finish
    - Flawed cylinders burst-test