The Pressure and temperature limits of the various .– Valves seat materials are shown below for valve sizes from 1/2″ to 16″ The body rating is independent of the seat rating and is shown by dotted lines.
1 - Graph 1 for PTFE Seat .
2 - Graph 2 for RTFE Seat (Reinforced glass ) .
Flow characteristics and size coefficients
The chart below and table for full bore and reduced bore are provided to assist in sizing – Valves for control applications.
Percentage of Ball Opening
Equal percentage flow characteristics, in simple terms,
means that a given perecentage change in the valve opening will produce the same percentage change in flow.
Kv indicates the quantity of m3/h of water at 20 C[70 F) which flows through the valve at a pressure drop of one bar.Cv indicates the quantity of N S Gallons per minute of water at 20 C (70 F) which flows through the valve at apressure
drop of one p.s.i. Cv=KvX1, 1688
Basic stem break-out torque values for full bore ball valves with PTFE seats in N.M.
Basic stem break-out torque values for reduced bore ball valves with PTFE seats in N.M.