| Gate valve |
Patent No.：ZL98241889.2 |
| Hydraulic safety valve |
Patent No.：ZL98241891.4 |
| Slip casing hanger |
Patent No.：ZL98241892.2 |
Cable seal penetrate system
in tubing head |
Patent No.：ZL98241890.6 |
| Big bore ball valve |
Patent No.：ZL200420109047.3 |
| Mental seals in stem |
Patent No.：ZL200420109046.9 |
| Y type self-tighten equipment |
Patent No.：ZL200520077335.X |
| Multibowl wellhead equipment |
Patent No.：ZL200620077839.6 |
| Expanding valve |
Patent No.：ZL200620077840.9 |
| New type gate valve |
Patent No.：ZL200620077841.3 |
Single-tapped slip casing
hanger |
Patent No.：ZL200620077844.7 |
| Convenient self-tighten seals |
Patent No.：ZL200620077845.1 |
| Mandral casing hanger |
Patent No.：ZL200620077843.2 |
| Mandral tubing hanger |
Patent No.：ZL200620077842.8 |
Running/retrieval tools for
tubing hanger |
Patent No.：ZL200620077846.6 |
