NEW BVAA Safety Valves Manual

The BVAA has just published its NEW Safety Valves Manual, which has been written for the benefit of end-users, and introduces all aspects of Safety Valves in one single, brand independent, publication. Service and maintenance organisations, component suppliers and valve specifiers will find it to be an essential reference manual.

What’s in the BVAA Safety Valves Manual?

It has been designed to assist end users in understanding the importance of providing the necessary information to a valve supplier, ensuring the correct valve selection for the application is made.

A safety device that is operated by the system pressure alone needs all the correct pieces to be in place within the complex process of specification, selection, installation, and maintenance if it is to operate correctly when called upon.

It introduces the entire process and contains a wide range of information that would normally only be found in design codes, standards, manufacturers’ selection data and operation and maintenance manuals. Combining this material into a single document makes it a useful source of information and reference material to anyone working with Safety Valves.

Some of the areas covered include:

Safety Valve Types

Over the years many different Safety Valve designs have evolved to provide the right overpressure solution for particular applications. The manual explains the main design variants in today’s market, covering a wide range of applications from low pressure tank vents and thermal relief through to modulating pilots and high-pressure power boiler Safety Valves.

Terminology

In the pressure equipment industry Safety Valves have a vital role to protect life and property from the hazards of overpressure. However, they also use a unique set of terminology to describe aspects of their performance, these need to be thoroughly understood if the end-user wants to be assured that the right Safety Valve has been selected, tested, installed, and effectively maintained for the application that it is protecting. The manual covers the major differences in the definition of important terms such as set pressure and effective areas that are commonly used by different manufacturers and product standards to highlight some of the potential pitfalls for the end-user.

Correct Sizing

The importance of sizing and selecting the right Safety Valve is fundamental, however it can be counterproductive to select an oversized valve in the belief that “it is better to be on the safe side”. The common problem of unstable performance due to oversized Safety Valves is covered in the manual by providing an explanation of the various sizing and capacity certification methods in common use today. A more complete understanding of the safety factors included in each method will help to avoid problems that may result in oversized Safety Valves being installed.

Correct Installation

Safety Valves are a medium operated valve designed to reliably convert the pressure energy in the process fluid into kinetic energy to allow the valve to open stably and discharge the correct amount of fluid to safely relieve the overpressure event. This performance relies upon the correct design of the inlet and discharge pipework because correct performance is only achieved from stable flow conditions being established when the valve opens. The common design requirements and operational problems associated with the installation of pipework for Safety Valves is covered in the manual along with a troubleshooting table to assist with diagnosing operational problems.

Testing Practices

Safety Valves are the most frequently tested valve on most plants due to safety related maintenance requirements however, there are many different methods of testing Safety Valves that are widely used including, workshop test benches, in-situ assisted lift testing and full overpressure tests on the plant itself. The advantages and disadvantages of the various test methods are covered in the manual to assist in the selection of the most appropriate methods for any particular application.

Personal experience has shown that it can take many years to gain the necessary understanding of the processes associated with the effective specification, use and maintenance of Safety Valves. The aim of this manual is to accelerate that process by introducing the reader to all the major aspects involved in the world of Safety Valves in a single publication. The breadth of information will be valuable to anyone regularly working with Safety Valves to supplement their understanding of this family of vital safety products.

Printed copies of the BVAA Safety Valves Manual are priced at £20.00 each, and available to purchase from our website: www.bvaa.org.uk or by emailing enquiry@bvaa.org.uk.

Published: 14th August 2023