Safety Valve (PRV)

Product Overview

The Safety Valve (PRV) is a spring-loaded pressure relief valve engineered to protect pressure vessels, boilers, pipelines, and process equipment from the hazards of overpressure. When system pressure exceeds the pre-set threshold, the valve opens automatically to discharge excess fluid or gas, then reseats once safe operating pressure is restored — all without requiring external power or manual intervention.

Working Principle

The valve operates on a direct spring-loaded mechanism. A calibrated compression spring holds the disc firmly against the seat at normal operating pressures. When upstream pressure rises to the set point, the hydraulic force on the disc overcomes the spring load, lifting the disc and allowing fluid to escape through the outlet. The full-lift design ensures rapid, complete opening at set pressure, providing maximum flow capacity and effective pressure relief. Once pressure drops below the reseating pressure, the spring returns the disc to the closed position.

Body Material Options

The PRV is available in three body material configurations to suit a wide range of media and operating environments:

• Brass — Ideal for water, air, and non-corrosive fluids in general industrial and HVAC applications.
• Bronze — Suitable for steam, hot water, and mildly corrosive media, offering excellent durability and thermal resistance.
• Stainless Steel (SS) — Recommended for aggressive chemicals, high-purity processes, and corrosive environments where maximum material integrity is required.

Bonnet Types

Two bonnet configurations are available to accommodate different installation and media requirements:

• Open Bonnet — Exposes the spring to the atmosphere, allowing visual inspection and suitable for non-toxic, non-flammable media.
• Closed Bonnet — Encloses the spring assembly, protecting it from environmental contamination and suitable for toxic, flammable, or odorous media where containment is critical.

Size and Pressure Range

The Safety Valve (PRV) is available in connection sizes from 1/4" to 4", covering a broad spectrum of pipeline and equipment configurations. The adjustable set pressure range spans 0.5 to 700 bar, making it suitable for low-pressure steam systems through to high-pressure hydraulic and process applications.

Certifications and Standards

The PRV is certified to internationally recognised safety standards, ensuring compliance with regulatory requirements across global markets:

• ASME — American Society of Mechanical Engineers certification for pressure relief devices.
• PED — Pressure Equipment Directive compliance for the European market.

Typical Applications

The Safety Valve (PRV) is widely used across industries wherever overpressure protection is required:

• Pressure vessels and storage tanks
• Steam boilers and heat exchangers
• Oil and gas pipelines
• Chemical and petrochemical process equipment
• Water treatment and HVAC systems
• Hydraulic and pneumatic systems