Pressure Relief Valves

A Pressure Relief Valve (PRV), also called Pressure Safety Valve (PSV) or Safety Valve, is a type of valve used in various hydraulic systems and industries to protect equipment, piping systems, and vessels from excessive pressure buildup. The fundamental function of a pressure relief valve is to release or discharge fluid from a system when the pressure inside the system exceeds a predetermined safe level. Once the pressure is reduced to a safe level, the PRV closes again, regulating pressure levels. This helps prevent potential damage to equipment, avoid explosions or ruptures, and ensure the personnel's safety.

Why Buy Pressure Relief Valves?

Pressure relief valves are essential safety devices that protect pressure vessels, pipelines, and other systems from overpressure conditions that could lead to catastrophic failures. These devices minimise equipment inefficiency failure, ensure overall operational reliability and boost productivity.

Selection Criteria for Pressure Relief Valves:

Selecting pressure relief valves is a critical process involving several key criteria to ensure their proper functioning and effectiveness. Some essential selection criteria for pressure relief valves include:

• Valve Type: Choose the one that best suits the specific application among various pressure relief valves.
• Capacity: The capacity of a relief valve must be sufficient to handle the maximum anticipated flow rate during an overpressure event. 
• Temperature Range: PRVs must be selected based on the system's temperature range to ensure the valve's proper operation and integrity at varying temperatures.
• Fluid Characteristics: Fluid properties such as viscosity, corrosiveness, toxicity, and phase (liquid or gas) play a role in determining the appropriate valve material and design.
• Materials of Construction: Valve materials must be compatible with the fluid and operating environment.
• Installation Requirements: The valve's installation orientation, piping configuration, and available space must be considered to ensure proper installation and function.
• Certifications and Standards: PRVs should meet industry standards and regulations.
• Reliability and Maintenance: Choose valves from reputable manufacturers with a history of producing reliable products. Consider ease of maintenance, availability of spare parts, and the valve's track record for long-term performance.
• Operating Environment: Environmental conditions, such as outdoor exposure, extreme temperatures, and corrosive atmospheres, can impact the valve's performance and longevity.
• Response Time: Valves with faster response times might be necessary for specific applications.
• Cost and Brand: Consider the price and brand for your specific PRV types.

Differentiating Pressure Relief Valves and Pressure Safety Valves:

Pressure relief valves and pressure safety valves operate similarly; however, they are often confused terms for users. These pressure regulators differ in slight differences in their operations and intended environments. For instance, PSVs operate efficiently as compared to gradual regulations of PRVs. PRVs are also preferred for regulating liquid pressure systems, while PSVs suit gas systems.  

Adjustable Pressure Relief Valves:

Adjustable pressure relief valves are essential components that allow operators to set the pressure at which the valve opens manually. These valves maintain the pressure within a system or equipment at a safe and predetermined level by releasing excess pressure when it rises above the set point. This is usually achieved by adjusting the spring tension using a handwheel, knob, or similar mechanism. Operators can tailor the valve's performance to the system's requirements by setting the valve to open at a specific pressure.

Typical Applications of Pressure Relief Valves:

PRVs are attached to various equipment, including pressure vessels, pipelines, storage tanks, water heaters, and boilers that regulate the optimised pressure flow. These devices find typical applications in various industrial settings, such as:

• Oil & Gas Industry
• Food Processing
• Pharmaceuticals
• Power Generation
• Industrial Automation
• Manufacturing Industry
• Plumbing Applications.