Description
Features
The valve has a full 2” ID minimum bore. With the hydraulic hold open mechanism, the flapper element is completely out off the flow or fluid path when engaged. This eliminates any possibilities to flow cut the flapper element and seat when bleeding off pressure at the cement unit. Volume control is essential and is maintained by using a hold open check valve.
The main seal is metal to metal between the flapper and the seat. As a secondary seal an o-ring is installed into a special o-ring groove. This prevents the o-ring from falling out during high flow operation.
Operation
The Hydraulic Hold Open Valve is installed on the Surface Test Tree, bolted onto the body between the flexible kill hose and the kill wing valve.
The main seal is metal to metal between the flapper and the seat, secondary seal is an o-ring installed in a special o-ring groove that prevent the o-ring from loosening during high flow operation . This also ensures efficient pressure integrity from zero pressure applied form the tubing side. The spring in the control chamber will return the flapper into its normal position when there is no hydraulic pressure applied through the control line, we have kept a very low spring force acting on the flapper, the intention of having this positive force in place is to assist closure in operation when there is very little flow forms the tubing side returning back to the cement unit. The internal pressure from the well bore will always act to close the valve, maintaining the fail close functionality in place. In addition a close assist control line can be utilized.
Specifications
Hydraulic Hold Open Check Valve
Description: Normal operated closed, hydraulic hold open.
Part number: TSI-110203
Working Pressure: 10 K PSI, 690 Bar
Working Temperature: -21 to 121 Celsius
End Connections: 2 1/16 in -10K, BX 152 Seal ring
Hydraulic connection port: 1/2” NPT Female
Dry Weight: 175 kg
Design Codes: API-SPEC-6A, DNV-OS-E101
Material: AISI 4130-75k API-6A-PSL3, AISI 4140 90KSI
Patent Pending number: NO20110108
Type Approved, DNV Certified: Yes