ICI's Actuator & Valve Industry Blog

How to Select the Right Valve (with Pros & Cons)

Posted on Mon, Feb 03, 2014

The suitability of a valve for a specific application is defined by the materials used in relation to the transported fluid as well as its mechanical design. Here is Indelac Valve Selection Guide.

Indelac Valve Selection Guide

Valve Selection Table

The tables below can be used as a valve selection guide taking into consideration the state of material, its nature and the function of the valve.

Conveyed Fluid Nature of Fluid Valve Function Type of Disc
Liquid Neutral (Water, Oil, etc) On/Off Gate
Rotary ball
Plug
Diaphragm
Butterfly
Plug gate
Control valve, modulating Globe
Butterfly
Plug gate
Diaphragm
Needle
Corrosive (Acid, alkaline etc.) On/Off Gate
Plug gate
Rotary ball
Plug
Diaphragm
Butterfly
Control valve, modulating Globe
Diaphragm
Butterfly
Plug gate
Hygienic (Food, beverages, drugs etc) On/Off Butterfly
Diaphragm
Control valve, modulating Butterfly
Diaphragm
Squeeze
Pinch
Slurry On/Off Rotary ball
Butterfly
Diaphragm
Plug
Pinch
Squeeze
Control valve, modulating Butterfly
Diaphragm
Squeeze
Pinch
Gate
Fibrous Suspensions On/Off, Control valve, modulating Gate
Diaphragm
Squeeze
Pinch

 

Conveyed Fluid Nature of Fluid Valve Function Type of Disc
Gas Neutral (Air, Steam etc) On/Off Gate
Globe
Rotary ball
Plug
Diaphragm
Control valve, modulating Globe
Needle
Butterfly
Diaphragm
Gate
Corrosive (Acid vapors, chlorine etc.) On/Off Butterfly
Rotary ball
Diaphragm
Plug
Control valve, modulating Butterfly
Globe
Needle
Diaphragm
Vacuum On/Off Gate
Globe
Rotary ball
Butterfly

 

Conveyed Fluid Nature of Fluid Valve Function Type of Disc
Solids Abrasive Powder (Silica, etc) On/Off, Control valve, modulating Pinch
Squeeze
Spiral sock
Lubricating powder (graphite, talcum, etc) On/Off, Control valve, modulating Pinch
Gate
Spiral sock
Squeeze

 

Valve Type Pros and Cons

Because everything is easier to understand with a table, here is another one summarizing pros and cons for the most common valves.

Valve Advantages Disadvantages
Butterfly Quarter turn Difficult to clean
Open port Difficulty with slurries
Used with chemical or corrosive media Throttling limited to low differential pressure
Compact, lightweight design Potential for cavitation and choke
Available in large sizes Unguided disc movement is affected by flow turbulence
Low pressure drop and high-pressure recovery  
High coefficient of flow
Ball Superior ease of operation  Poor throttling characteristics
Maintains and regulates high volume,  Difficult to clean, leads to contamination
high pressure, and high temp flow  
Rugged construction and long service life
Low purchase and maintenance cost
Able to function without side loads
Permits inspection and repair of seats and seals without removing the valves' body from the line
Does not require lubrication
Diaphragm Extremely clean Can only be used in moderate temperature (-60 to 450ºF)
Leak proof seal Can only be used in moderate pressures (approximately 300psi)
Tight shut-off Cannot be used in multi-turn operations
Easy maintenance No industry standard face-to-face dimensions
Repairs can be made without  interrupting pipe line The body must be made of corrosive resistant material
Reduce leakage to the environment  
Gate Available in large sizes Low pressure limitations
Can be used with slurries and viscous liquids Slow open and close time
Used as a shut off valve Erosion of the seat and disk can occur
Easy to maintain and disassemble Poor throttling characteristics
Inexpensive Difficult to repair
Inherently fire-safe (when used with a metal sheet) Should not be used in sanitary applications
Bidirectional  
Globe Can be fast-acting High head loss
Precise control Large opening for disk assembly
Can be used in high-pressure systems Heavier than other valves
  Cantilevered mounting of the disk to the stem
Low coefficient of flow
Not good for clean or sterile applications
Pinch Very Clean Cannot be used in high temperature applications
Excellent drainage Cannot be used in high pressure applications
Minimal turbulence Cannot be used with gas media
Low airborne contaminants  
Low maintenance
Low weight
Can be used in explosion-proof lines
Inexpensive

Once the right valve has been selected, it is time to select the right actuator! See link below to Indelac Actuator Selection Guide:

How to select an Actuator - Comprehensive Guide