Introducing the masters of master valves.
Greater. Stronger. Better.
The GSB Master Valve is the ONLY high pressure gas shutoff and control valve that received the approval for 6,000 PSIG operating pressure in oxygen service for commercial applications worldwide, making it the safest, most reliable and the highest-pressure valve in the industry.
Master Valve GSB-4
High Pressure Gas Shutoff & Control Valve
The new CPV High Pressure Master Valve is optimized for the critical requirements of gas cylinder fill plants, panels, tube trailers, and manifolds This oxygen-service brass valve design utilizes the same reliable sealing mechanism as CPV’s valves which have been used throughout the high pressure piping industry for more than 75 years!
With robust design & leak-free operation, you can count on CPV to provide the most dependable high pressure gas shutoff and control valve in the industry! Our standard is the NEW STANDARD in the Master Valve Market!
Technical Data
-
Operating Pressure Range:
6000 PSIG (414 BAR) Oxygen
6000 PSIG (414 BAR) Inert -
Operating Temperature:
-15°F to 400°F | (-26°C to 205°C) -
Flow Coefficient (CV):
2.78 -
Production Testing: (100% Factory Tested)
6000 PSIG Seat Test (414 BAR)
9000 PSIG Shell Test (621 BAR) -
Panel Mount:
Standard -
Full Vacuum:
Standard
OXYGEN SAFE
- Certified & Approved per ISO 10297 and ISO 7291
- 100% Oxygen Cleaned & Packaged per CGA G-4.1 and ASTM G93 standards
PRESSURE & FLOW
- Full Vacuum Standard
- 6000 psig Oxygen Service
- ASME Section VIII, ASME B31.3
- Highest Flow Coefficient in the industry
- Soft Seated sealing for bubble-tight,
leak-free operation
FEATURES & BENEFITS
- Ergonomic handle designed for comfort & easy operation
- Low torque, even at full pressure
- Panel mount standard
- Higher performance alternative to under-performing, lower quality & lower pressure rated valves
Materials of Construction
Ordering Information
Master Valve GSB-6
High Pressure Gas Shutoff & Control Valve
The new CPV High Pressure Master Valve is optimized for the critical requirements of gas cylinder fill plants, panels, tube trailers, and manifolds. This oxygen-service brass valve design utilizes the same reliable sealing mechanism as CPV’s valves which have been used throughout the high pressure piping industry for more than 75 years!
With robust design & leak-free operation, you can count on CPV to provide the most dependable product in the industry! Our standard is the NEW STANDARD in the Master Valve Market!
Technical Data
-
Operating Pressure Range:
6000 PSIG (414 BAR) Oxygen
6000 PSIG (414 BAR) Inert -
Operating Temperature:
-15°F to 400°F | (-26°C to 205°C) -
Flow Coefficient (CV):
2.78 -
Production Testing: (100% Factory Tested)
6000 PSIG Seat Test (414 BAR)
9000 PSIG Shell Test (621 BAR) -
Panel Mount:
Standard -
Full Vacuum:
Standard
OXYGEN SAFE
- Certified & Approved per ISO 10297 and ISO 7291
- 100% Oxygen Cleaned & Packaged per CGA G-4.1 and ASTM G93 standards
PRESSURE & FLOW
- Full Vacuum Standard
- 6000 psig Oxygen Service
- ASME Section VIII, ASME B31.3
- Highest Flow Coefficient in the industry
- Soft Seated sealing for bubble-tight,
leak-free operation
FEATURES & BENEFITS
- Ergonomic handle designed for comfort & easy operation
- Low torque, even at full pressure
- Panel mount standard
- Higher performance alternative to under-performing, lower quality & lower pressure rated valves
Materials of Construction
Ordering Information
Master Valve GSB-2
High Pressure Gas Shutoff & Control Valve
The new CPV High Pressure Master Valve is optimized for the critical requirements of gas cylinder fill plants, panels, tube trailers, and manifolds. This oxygen-service brass valve design utilizes the same reliable sealing mechanism as CPV’s valves which have been used throughout the high pressure piping industry for more than 75 years!
With robust design & leak-free operation, you can count on CPV to provide the most dependable product in the industry! Our standard is the NEW STANDARD in the Master Valve Market!
Technical Data
-
Operating Pressure Range:
6000 PSIG (414 BAR) Oxygen
7800 PSIG (538 BAR) Inert -
Operating Temperature:
-15°F to 400°F | (-26°C to 205°C) -
Burst Pressure:
38,925 PSIG (2684 BAR) -
Flow Coefficient (CV):
2.78 -
Production Testing: (100% Factory Tested)
7800 PSIG Seat Test (538 BAR)
9000 PSIG Shell Test (621 BAR) -
Panel Mount:
Standard -
Full Vacuum:
Standard
OXYGEN SAFE
- Certified & Approved per ISO 10297 and ISO 7291
- 100% Oxygen Cleaned & Packaged per CGA G-4.1 and ASTM G93 standards
PRESSURE & FLOW
- Full Vacuum Standard
- 6000 psig Oxygen Service
- ASME Section VIII, ASME B31.3
- Highest Flow Coefficient in the industry
- Soft Seated sealing for bubble-tight,
leak-free operation
FEATURES & BENEFITS
- Ergonomic handle designed for comfort & easy operation
- Low torque, even at full pressure
- Panel mount standard
- Higher performance alternative to under-performing, lower quality & lower pressure rated valves
Materials of Construction
Part Number:
-
GSB-48R-2-SS316L
(316L Stainless Steel) -
GSB-48R-2-M
(Monel®)
Part Number:
-
GSB-50N-2-SS316
(316 Stainless Steel) -
GSB-50N-2-M
(Monel®)
O-SEAL® tailpieces come standard with EPDM O-Ring (unless otherwise specified)
Ordering Information
Frequently Asked Questions
What is a master valve on a gas cylinder?
A master valve is the primary isolation valve installed directly on a high-pressure gas cylinder or manifold. It controls the main flow of gas into or out of the system. CPV’s master valves (like the GSB series) are critical safety devices designed to handle high-pressure oxygen and other industrial gases reliably.
CPV’s Solution: CPV’s GSB Master Valves set the industry standard for safety. They are tested to exceed CGA G-4.1 oxygen cleaning standards and feature a robust brass body that can withstand pressures up to 6,000 PSI, ensuring fail-safe operation in fill plants and tube trailers.
Why are master valves important for gas cylinder safety?
Master valves are the first line of defense in gas safety. They must withstand full cylinder pressure (often 3,000-6,000 PSI) and provide a bubble-tight seal to prevent dangerous leaks. For oxygen service, they are specially designed and cleaned to prevent ignition hazards during pressure surges.
CPV’s Solution: Safety is built into every CPV master valve. Our valves undergo rigorous adiabatic compression testing to ensure they can handle the heat generated by rapid pressurization of oxygen, preventing the catastrophic fires that can occur with inferior valves.
How do you open and close a gas cylinder master valve?
To open, turn the handwheel counter-clockwise slowly to prevent heat of compression (especially with oxygen). To close, turn clockwise until firm. For many industrial valves, it’s recommended to open them fully to “back-seat” the stem, which seals the stem packing and prevents leaks during use.
CPV’s Solution: CPV Master Valves are designed with an ergonomic handle and low-torque operation, making them easy to open slowly and safely. The stem design ensures a positive shutoff with minimal force, reducing operator fatigue and the risk of overtightening.