Conventional Safety Valve

Technical Summary

Nominal Size: ½” to 12”

Pressure Class: Class 150 to Class 2500

Temperature Range: -29°C to 538°C

Design Standards: API 526, ASME Section VIII, ASME B16.34

Set Pressure Range: As per system requirement

End Connections: Flanged / Butt Weld

Construction and Materials

Body and Pressure Retaining Parts

• ASTM A216 WCB
• ASTM A351 CF8M
• ASTM A217 WC6
• ASTM A217 WC9
• ASTM A182 F316

Internal Components

• Disc: ASTM A182 F316 / Hard faced (Stellite)
• Seat: Stainless Steel / Stellite faced
• Stem: ASTM A182 F6a / ASTM A182 F316
• Spring: Chrome silicon alloy steel / Inconel (for high temperature service)

Sealing System

• Seat Sealing: Metal to metal sealing with optional hard facing for durability
• Gasket: Spiral wound gasket with graphite filler

Functional Design

Conventional Safety Valve is a spring-loaded pressure relief device designed to protect equipment and piping systems from overpressure conditions. The valve operates by balancing system pressure against a pre-set spring force.

When system pressure exceeds the set pressure, the valve opens automatically to discharge excess pressure. Once the pressure falls below the reseating value, the valve closes to restore system integrity. The performance of a conventional safety valve is influenced by back pressure, making it suitable for applications where back pressure is minimal and stable.

Material and Grade

Standard Materials

Component	Material	Grade	Typical Application
Body	Carbon Steel	ASTM A216 WCB	General steam and utility services
Body	Stainless Steel	ASTM A351 CF8M	Corrosive and process media
Body	Alloy Steel	ASTM A217 WC6 / WC9	High temperature service
Disc & Seat	Stainless Steel with Stellite overlay	ASTM A182 F316	Wear resistance and tight sealing
Stem	Stainless Steel	ASTM A182 F6a / F316	Load transfer and corrosion resistance
Spring	Alloy Steel / Inconel	High strength spring material	Pressure set control and high temperature resistance

Extended Materials (On Request)

• Hastelloy C276 for aggressive chemical service
• Inconel 625 / 718 for high temperature applications
• Duplex Stainless Steel (F51) for chloride environments

Additional Information

Valve Type	Conventional Safety Valve
Pressure Function	Overpressure protection
Operation	Spring loaded
Back Pressure Sensitivity	Affected by built-up back pressure
Installation	Vertical installation required
Service Media	Steam, gas, vapour

End Connections

• Flanged as per ASME B16.5
• Butt weld as per ASME B16.25

Applications

• Oil and gas industry: pressure relief in pipelines and processing units with low back pressure
• Power generation: steam boiler protection and auxiliary systems
• Water and wastewater treatment: pressure protection in pumping and distribution systems
• Refining and petrochemical industry: general pressure relief in process lines
• Pulp and paper industry: steam system safety applications
• General industrial systems: utility and compressed gas systems with stable operating conditions