There are various needle valves which can be gotten from KP-LOK and some people have been commissioned to assess whether the approach which is used for emergency shutdown valves in the upstream applications is appropriate.
We are taking a look at trunnion-mounted metal-sealed ball valves which is fitted with a spring-return and this is mainly used in the upstream applications. However, most of the findings can also be used in the downstream petrochemical applications.
Those that would do the assessment are engineer and the first thing which is done was to discuss with the end users about the possible experiences and also read the application standard thoroughly. There was discussion with the companies which is making valves as well as actuators for their applications.
Although, there are some people that are not aware of the topic but it is well known to the end user organizations such as WIB. Several documents have been published about them but the summary is that the valve should be properly handled so that the control would be easy to control. However, there are some people that have said the reliability of the valve is about getting a successful connection between the actuator engineer and valve engineer.
ESD is referred to as emergency shutdown valve and is used for shutting or opening the pipeline in an emergency situation. I have been able to coin the term SVRP which is short for SIS valves reliability prediction because I would like to develop a tool which can be used effectively in sizing and selecting the devices based on the torque. The word torque is used because there is need to move to its safe position.
When the actuator spring for a fail close application is considered, the one which is compressed remain energized for a long period of time. How can you ascertain it will work for a long period of time? What can be the effect of ambient temperature or particles in the process fluid or the deformation of the elastomeric seats which require the operation of the valve? This is why it is essential to know torque on demand figures. However, some valve user has started requesting about data on the dormancy performance for the company that supply valve to them.
This is not in my general experience because most of the trunnion-mounted ball valves are manual valves and are also fitted with a hand wheel, not the actuator and this make torque figure irrelevant. However, several valve makers have the data and are willing to share. This will help in obtaining a good result which will help in the industry.
There are manufacturer that offers valves as well as actuators which is certified by the SIL and this is a good indication to safety but whenever you go through the certificate and search for the word torque, you may be unable to find it. However, torque is probably the most critical factor in the ESD valve system. So it can be deduced that the SIL rating is sometimes used to create a false sense of security in the field.
However EMV is very safe and reliable option which has wide application in upstream and downstream sector and can be used by engineers to achieve the desired result.