To change the text size, hold down the Ctrl/Cmd key and press + to enlarge or - to reduce

Sitemap LinkedIn
- Improving well performance and integrity

Master Surface Annulus Safety Valve (MSAS)

MSAS - Master Surface Annular Safety Valve
MSAS-G (Integrated in API gate valve)
MSAS-G (Integrated in API gate valve)
MSAS (Actuator and the SAS valve)

Hydraulically activated barrier valve installed in the wellhead VR profile. Assures well integrity even upon impact or collision.


Fail safe close barrier valve provides an independent primary barrier for gas lifted, gas vented or for wells with sustained annulus pressure.




Gas lifted, gas vented or wells with sustained annulus pressure pose a considerable risk to personnel and facilities. In these applications annulus gate valves and ring gaskets are the primary well barrier. Gate valves provide only a single barrier, which can be breached upon impact or collision. 


Regulatory and/or company requirements may demand mitigation for the risk that high gas volume poses.



The MSAS, provides an additional independent barrier in the wellhead VR profile. The MSAS is hydraulically operated and connected to ESD. Should an impact or collision take place, the API 6FD/FB fire tested barrier valve locked in the VR profile will close and remain within the wellhead, thus securing the annular volume of hydrocarbons.


The MSAS system can be integrated in an API gate valve (MSAS-G) and has a smaller footprint       as the valve actuator is installed within the gate valve bore (see illustration on next page).



  • Based on API 6A
  • Fire tested to API 6FD & 6FB
  • Bi-directional flow
  • For gas injection and annulus venting applications
  • Fail safe close barrier valve
  • Independent barrier
  • NORSOK D-010 compliant



  • Enhances well integrity
  • Can be used to substitute the annular safety valve
    or downhole gas vent valve, or similar down hole
  • Eliminates need for ESD gate valve
  • Easy installation and service, even in live wells
  • No piping modification required (MSAS-G)



Size Range, in.

2-1/6 to 3-1/8
Valve/ Actuator Material Alloy K500
Seals material FKM/PEEK/PTFE
Pressure Rating, psi [Mpa] 10 000 [69]
Temperature Class, L-U °F [°C] -51 to 250 [-46 to 121]
Flow Area Range, in² [cm²] 0.15 - 1 [0.97 to 6.45]
Min. Hydr. Pressure, psi [Mpa] 2 500 over inj. pressure [10.3]
Flow Rate Range (fluid), bbls/min [l/min] 1 - 5 [159 to 795]
Applicable Standard API 6A

Make inquiry

Thank you for your inquiry. We will contact you as soon as we can

Please fill all the required fields!

Error occured