Different Types of Valves based on their Functions

These are different types of valves based on their functions.

  1. SXV (Shut Down Valves) : They are typically gate valves. Basically they are fully on or off and are not meant for controlling flow. During any emergency situation they are used to completely stop the flow of a fluid to prevent any kind hazardous situations. e.g if there is any leakage or spillage of hydrocarbons leading to fire.
    Although you have written it as SXV we call it as SDV.

  2. XV (On off valves) : They are also like SDV s meant for starting or stooping a flow. They are used for normal isolation of any equipment in a plant like pump,vessel,exchangers,control valves.

The later three categories are Control valves used to regulate Temperature (TV) , Pressure (PV) , Flow (FV). They all are globe valves. They all have the same mechanism and operating principle just their name differs based on the parameters they are used to control.

There is one more control valve which is LV(Level control).

SXV - shut down valve (emergency shut down)

XV - just an actuated on off valve

TV - control valve that changes opening % based on temperature (from a temperature transmitter)

PV- control valve that changes open % based on pressure transmitter feeback

FV- same as above but from flow meter


The on/off valves (sxv, or xv) can also be the ball or butterfly valves.

It depends on the aplication what type can be used. For bigger pipe size it has a more economical benefit to use the butterfly valve.

If you want a minimal pressure loss over the valve, you can use the (full bore) ball valve.

The ball valve can even be used as a control valve, but keep in mind that the controlability is not as good as the globe valve.