Pressure relief valves are a type of safety valve used to protect equipment and systems from excessive pressure. The pressure-reducing function of the valve is achieved by allowing the flow of gas or liquid to discharge through an opening, usually under reduced pressure, back into the system or atmosphere.

 

Pressure relief valves are used in many different types of systems and applications, including:

 

• Gas supply lines for ranges, ovens and other gas appliances
• Pressurized tanks for water heaters and boilers
• Storage tanks for liquids such as propane and natural gas
• Pressurized lines in chemical plants
• Boiler feedwater lines

 

The purpose of a pressure relief valve is to limit the pressure in a system by discharging excess gas. This prevents damage to equipment, injury or death caused by over-pressurization of the system. The function of a pressure relief valve is similar to that of fuses, circuit breakers and contactors, which are all considered safeguards against electrical hazards.

 

Difference between Pressure relief valves and safety valves

 

Pressure relief valves and safety valves are both types of valves that are used to control the pressure in a system. The main difference between these two valves is that pressure relief valves are designed to relieve excessive pressures, while safety valves are designed to protect against over pressurization.

 

Let’s understand each one in detail. 

 

Pressure relief valves are designed to protect equipment from damage caused by excess pressure. They accomplish this by releasing some of the fluid back into the system when a predetermined pressure is reached. This allows the pressure in the system to be reduced without damaging any components.

 

Pressure relief valves typically have a spring-loaded valve that opens when the pressure exceeds its set point by a certain amount. In many cases, this type of valve will open automatically when it reaches its set point, but it can also be manually operated as well.

 

Safety valves protect against over pressurization by allowing fluid to escape from the closed system before it builds up too much pressure and causes damage or injury. For example, if there is an overpressure event on a pipeline or tank due to an equipment failure or other event, then a safety valve will open and allow excess fluid to escape before it causes any damage or injures people around it.

 

Types of Pressure Relief Valves

 

In the world of pressure relief valves, there are many different types. To help you understand them, here is a list of the most common types of pressure relief valves and what they do.

 

• Check Valve: A check valve is used to prevent backflow. It is commonly used in water systems where there is a risk of contamination by backflow.

 

• Control Valve: A control valve is used to regulate or control the flow of fluid under pressure.

 

• Diaphragm Valve: This type of valve uses a diaphragm to seal itself. The diaphragm expands and contracts as needed to open and close the valve. A diaphragm valve is commonly used with water systems because it can handle high pressures without leaking.

 

• Float Valve: A float valve uses an adjustable weight to seal itself closed until enough pressure builds up inside the pipe for the weight to be lifted off its seat, allowing fluid to flow through the pipe again.

 

Potential line of defense against relief events

 

The most basic line of defense against relief events is to prevent them from happening in the first place. This can be done by following good engineering practices and by using pressure relief valves to limit overpressure events.

 

Pressure relief valves should be used in situations where there is a possibility of overpressure, for example:

 

• When a tank is being filled or emptied at high flow rates
• When a vessel is being pressurized or depressurized
• When there is a risk of liquid being trapped in the piping system
• While these are the most common examples, they are not exhaustive. If you are unsure whether or not your application requires a pressure relief valve, please contact us for advice.

 

How can you adjust a relief valve while working on them?

 

A relief valve is a device that automatically opens to release pressure when the pressure within a system reaches a certain level.

A relief valve is usually used as part of a piping system, on an appliance, or on an industrial process. For example, if you have a water heater with an automatic pilot light, there will be a relief valve attached to it. When the water reaches its boiling point, it will open and release some of the steam and pressure so that the pilot does not get damaged.

 

 

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The purpose of this article is to provide information on how to adjust a relief valve.

 

Step 1: Turn off all power and gas supply lines leading into the unit you wish to adjust (or shut off main power).

 

Step 2: Disconnect any wires leading into or out of the unit. Be sure to mark them clearly so they can be reconnected later.

 

Step 3: Open any valves leading into or out of the unit until they are fully open (no resistance). This should allow all air pockets in the lines to escape and relieve any pressure inside those lines. Do not close any valves until instructed otherwise.

 

Sri Ank Enterprise is one of the leading pressure relief valve manufacturers in India. We offer a wide range of pressure relief valves used in various industrial applications.

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The following are the main applications of our Pressure Relief Valves:

1. Chemical Industry: These valves are used to relieve pressure from various chemical industries like fertilizer, sugar and paper mills, distilleries etc.
2. Oil Refineries: The Pressure Relief Valve is used in an oil refinery to control the pressure of sulfuric acid in the distilling column.
3. Pulp & Paper Mills: These valves are used for controlling pressure on pulp machines and also for relieving excess pressure from pulp machines during breakdowns or maintenance purposes.
4. Cement Industries: These valves are used for controlling pressure on cement kilns and also for relieving excess pressure from the kiln during maintenance work or breakdowns of any kind at a cement plant site.

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