1. Raw materials test including mechnical and chemical test.
2. Casual inspection of all valve parts body, disc, stem, seat and other componests.
3. Proccessing test for all parts.
4. Assembling check of all parts again.
5. First pressure test after main assembling.
6. Secondary pressure test with finished product.
7. Casual inspection of surface and marks by quality controller.
8. Finial inspection when packing.