The GIS Valve® is a hydraulic pilot operated safety relief valve engineered to provide reliable overpressure protection for high-pressure steam systems in marine, utility, industrial, and power generation applications.
Designed for systems operating up to 3000 PSI and 1100°F, the GIS Valve delivers exceptional operational reliability, improved safety, reduced steam leakage, and simplified maintenance compared to conventional safety valves.
Originally developed for the U.S. Navy in 1978, the GIS Valve has since been installed on more than 400 non-nuclear Navy vessels and is trusted across critical industrial steam applications worldwide.
Greno Industries manufactures the GIS Valve in Scotia, New York using precision CNC machining and AS9100:2016 / ISO9001:2015 certified quality systems. We are also ITAR registered.
The GIS Valve® is a hydraulic pilot operated safety relief valve engineered to provide reliable overpressure protection for high-pressure steam systems in marine, utility, industrial, and power generation applications.
Designed for systems operating up to 3000 PSI and 1100°F, it delivers exceptional operational reliability, improved safety, reduced steam leakage, and simplified maintenance compared to conventional safety valves.
Originally developed for the U.S. Navy in 1978, the GIS Valve has since been installed on more than 400 non-nuclear Navy vessels and is trusted across critical industrial steam applications worldwide.
Greno Industries manufactures the GIS Valve in Scotia, New York using precision CNC machining and AS9100:2016 / ISO9001:2015 certified quality systems. We are also ITAR registered.
The GIS Valve® and remote pilot panel are located away from the boiler to improve safety, reliability, and accessibility.
Unlike conventional steam safety valves, the GIS Valve uses a remote hydraulic pilot system that isolates sensitive controls from extreme boiler temperatures. This innovative design improves pressure control accuracy while helping reduce maintenance requirements and operational inefficiencies.
The GIS Valve was engineered specifically to solve the limitations commonly associated with traditional boiler safety valve systems.
High accuracy and repeatability at peak boiler loads
Virtually leak-free operation
Reduced steam losses and improved efficiency
Remote pilot panel for safer operation
Elimination of simmering and unnecessary valve cycling
Simplified maintenance through modular construction
Stainless steel construction for long-term durability
Retrofit compatibility with existing steam systems
No external power supply required for operation
The GIS Valve system operates using the pressure-loading principle.
During normal operation, boiler pressure holds the safety valve closed. When the pilot valve’s set pressure is reached, the pilot valve vents the loading pressure from the safety valve, allowing the valve to open and safely relieve excess pressure.
The complete system consists of:
Safety valve assembly
Remote pilot panel
Pressure sensing lines
Hydraulic control components
Water supply connections
This design eliminates many common issues associated with traditional steam drum pilot valves, including excessive steam leakage, temperature instability, and exhaust piping complications.
| Specification | Value |
|---|---|
| Valve Type | Hydraulic Pilot Operated Safety Relief Valve |
| Maximum Pressure | Up to 3000 PSI |
| Maximum Temperature | Up to 1100°F |
| Construction Material | Stainless Steel |
| Applications | Marine, Utility, Industrial, Power Generation |
| Certifications | AS9100:2016, ISO9001:2015 |
| Country of Origin | USA |
| Installation Options | New Systems & Retrofit Applications |
| GIS Valve | Conventional Safety Valves |
|---|---|
| Remote pilot operation | Direct-mounted controls |
| Reduced steam leakage | Leakage prone |
| Improved operator safety | Boiler exposure during adjustment |
| More stable pressure control | Temperature-sensitive operation |
| Modular maintenance-friendly design | More complex servicing |
| Reduced valve wear | Increased cycling and simmering |
| Retrofit capable | Often requires full redesign |
The GIS Valve’s remote pilot panel is mounted away from the boiler in a lower temperature operating environment, improving both safety and operational performance.
Improved pressure setting accuracy
Reduced exposure to hazardous operating conditions
Easier maintenance and adjustment access
More stable performance under varying temperatures
Elimination of steam exhaust from the pilot valve
Reduced maintenance and lifecycle costs
Unlike conventional pilot valves, the GIS pilot valve controls the safety valve hydraulically without exhausting steam during operation.
One of the GIS Valve’s most valuable advantages is its ability to integrate into existing steam systems without requiring a complete system overhaul.
Greno Industries can custom-engineer a GIS Valve solution to work with your current infrastructure, helping facilities modernize boiler safety systems while minimizing downtime and capital expenditures.
Every GIS Valve is manufactured using precision CNC machining and carefully ntrolled materials to ensure consistent performance and maximum durability.
Critical seating components utilize hard surface alloys to maximize operational life under demanding conditions while minimizing maintenance requirements.
The valve’s stainless steel construction provides exceptional resistance to corrosion, wear, and harsh operating environments.
The GIS Valve was originally developed for demanding U.S. Navy applications where reliability and operational performance are mission critical. Today, the valve continues to support marine steam systems operating in harsh environments worldwide.
Utility and industrial power plants utilize the GIS Valve to improve steam pressure control, operational efficiency, and long-term system reliability in the power generation industry.
Industrial facilities benefit from simplified maintenance, retrofit flexibility, and reduced steam leakage in high-pressure steam applications.
The GIS Valve supports continuous-duty steam operations in pulp and paper facilities where operational uptime and reliability are essential.
Greno Industries provides fully integrated support from engineering through final manufacturing and testing.
Engineering and design support
Precision CNC machining
CAD/CAM manufacturing
Assembly and testing
Quality inspection
Field support and service
24/7 support availability
Greno Industries combines advanced manufacturing technology with decades of steam system expertise.
A pilot operated safety relief valve uses a secondary pilot control system to manage the opening and closing of the main relief valve. This provides more accurate pressure control and reduced steam leakage compared to conventional safety valves.
The GIS Valve is used in marine, naval, utility, industrial boiler, power generation, and pulp and paper applications.
The GIS Valve is designed for steam systems operating up to 3000 PSI and temperatures up to 1100°F.
Yes. Greno Industries can engineer retrofit solutions that integrate into existing steam systems without requiring a complete redesign.
The valve’s pressure-loading design eliminates many common leakage paths associated with traditional pilot-operated systems.
Yes. All GIS Valves are proudly manufactured in Scotia, New York by Greno Industries.
Speak With an Engineer
Download Technical Documentation
Discuss Retrofit Options
Greno Industries
Scotia, New York
AS9100:2016 & ISO9001:2015 Certified
Made in USA