To Specify a Top Line 3-Way Valve – Essential Information Is Needed

Three-way valves are used in a number of applications with a primary function of diverting flow in a line.  To specify any valve there are essential pieces of information that are required to ensure that the correct valve type and configuration are selected for the intended application.  To specify a 3-Way valve, there is a minimum of data (parameters) that must be identified, and others which are helpful in determining the best choice of valve for the application.

The table below segregates the essential information required as well as additional information which should be provided if known.  For each parameter, a brief description is provided (What Column) and the reason the information is required (Why Column) is also provided.  Please utilize this resource when engaging with Top Line to source your 3-Way Ball Valves, and if you require assistance don’t hesitate to contact us!



Parameter What  Why
Process Fluid What is the product being pumped? (e.g. Milk, Water, Cleaning Solution, etc…) Essential to understand in order to specify the correct valve seal.
Clean in Place (CIP) Y / N If Yes, need to understand what the cleaning solution is and or if steam is to be used for seal selection.
Pressure At what pressure is the process occurring (psi) Valve pressure rating
Temperature and Temperature Range At what temperature is the process occurring C or °F) Seal material selection and in conjunction with the process pressure could change valve selection and sealing material selection
Line Size Size of process line mating with valve Ensure compatibility with valve connections
End Connections Connection (Weld, Tri-Clamp, other, etc.) Ensure compatibility with valve connection configurations
Sealing Material What is the desired seal material? Typical choices include PTFE, Modified PTFE, Reinforced PTFE, 50-50 SS-PTFE, HMWPE It is essential that the material used to seal the valve is compatible with the process fluid, as well as the temperature range over which the valve is operating.  If unclear, Top Line engineering can recommend a material, and in those instances the more that is known about the application the better.
Valve Material What is the desired valve material? Typical choices include CF3M/316L, CF8/316, and WCB (Carbon Steel) The valve body material must be compatible with the existing process lines and suitable for the process temperature and pressure.
Surface Finish What is the required surface finish? Certain industries have requirements for surface finish.  Specifying the industry helps Top Line ensure that the appropriate surface finish is selected.
Surface Treatment Is Electropolishing required? Electropolishing will create a surface with increased luster, and more importantly, increased resistance to corrosion.


Parameter What  Why
Viscosity Ability of the fluid to resist a shear force. Actuator motor sizing
Cv (desired) or

Δ psig

Flow Coefficient (expressed as the flow rate in gallons of 60°F water which will pass through a valve in one minute at 1psi ΔP.) The differential pressure across the valve can also be provided. The process system is comprised of the various components; valves, piping runs (of various sizes), elbows, T’s, Heat Exchangers, Filters, etc.  Each of these components contribute resistance to the flow of the process fluid in the system.  Valves are a significant contributor to the overall flow resistance and understanding the Cv for a valve is important to the system designer for either a new system or if the valve is replacing an existing component as it effects the over-all system resistance.
Specific Gravity Specific Gravity or Weight/gallon (Specific Gravity is a dimensionless number) Specific Gravity is a ratio based on the density of the process fluid compared to water. Fluids with specific gravities significantly different from water may require additional consideration when selecting the valves.


Actuation methods for a 3 Way Ball Valve are discussed below, and it is important to understand that the method of actuation for the valve must be considered as part of the valve selection effort.  Valves are mechanical devices which direct and control the flow of the process fluid, and to perform this function they must be paired with a method to actuate them. (Similar to a pump and motor combination.)  Just as a pump cannot perform its’ function without a prime mover such as a motor, a valve cannot perform its’ function without an actuator. The most common method of actuation is a lever or hand-wheel which is manually moved by the operator to align the valve to the desired position.  The method of actuation tends to be a secondary consideration, however depending on the available infrastructure at the process location, only certain types of actuators may be viable. (e.g. only DC control voltage is available for valve control.)

Method & Configuration Considerations 
Manual Lever / Pipe Handle or Gear Operator
Pneumatic Rack & Pinion Material Preference – Stainless Steel or Aluminum
– Spring Open / Air Close Normally Open
– Air Open/ Spring Close Normally Closed
– Air Open / Air Close Double Acting
Electric (ONLY for ¼ Turn or 90°) applications 24VAC, 24VDC, 220VAC, 115VAC, 220VAC

Area Rating (Wash-down or Explosion Proof)


After specifying the correct valve and method of actuation, the last step in the process is to combine the information in order to have the valve and actuator configured correctly for the application.  Listed below are possible arrangements for the control state of the valve.  The diagrams determine how the valve will control the process and they should be used to communicate to Top Line how to set up the valve/actuator assembly based on the ball pattern, type of actuator, and designation code. (For example as shown below: L-BALL / Counter Clock Wise (CCW) TURN 90° ACTUATOR / A1)

Learn More About TOP-FLO® 3-Way Ball Valves (3-A) 

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