Application parameters

General
Enter exact DN size (e.g. 15, 25, 50, 100, 200…)

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Set your application parameters on the left and click Find matching products

Actuator selection

Valve details
Actuation requirement
Selects which torque column from the FIG 843/844 datasheet is used for compatibility checking.
Enter valve break-away torque if known. Actuators with less capacity will be flagged.

Select valve type and size to find compatible actuators

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Pick a valve type and size on the left to see compatible actuators with ISO mount and torque details.

Engineering Calculators

Based on John Valves internal calculation sheets. All results are indicative — verify with engineering before quoting.

🔧 Globe Valve — Stem Torque & Thrust

Calculates actuator/gearbox torque and stem thrust for rising-stem globe valves. Valve factor: 1.5 below DN50, 1.15 DN50 and above. (JV VALVE_CALCULATIONS.xls)

⚠ Gland friction thrust: ≤DN25 = 1000 lbf, ≤DN50 = 1500 lbf, >DN50 = 2500 lbf. Add 30% safety factor for actuator sizing.

🔧 Gate Valve — Stem Torque & Thrust

Calculates gearbox torque for Fig 600 (NRS) and Fig 601 (OS&Y rising stem) gate valves. Valve factor = 0.35. (JV VALVE_CALCULATIONS.xls)

⚠ Gland thrust: ≤DN25 = 1000 lbf, ≤DN50 = 1500 lbf, >DN50 = 2500 lbf. For hot gas/steam apply factor 0.45 to torque.

🔧 Butterfly Valve — Torque Estimate

Estimates bearing friction torque (Tb) and seal friction torque (Ts) for large concentric butterfly valves. Based on JV Butterfly Torque Calc sheet.

⚠ This is the break-away (unseating) torque only. Add hydrodynamic torque for flow control applications. Apply ×1.3 safety factor for actuator selection.

🔧 Knife Gate Valve — Stem Thrust & Torque

Calculates stem thrust and torque for knife gate valves. Based on JV Knife_Gate_Valves.xls. Valve factors: crack-close=0.3, crack-open=0.2.

⚠ Add 30% safety factor to torque for actuator/gearbox selection. Check stem buckling for extended-bonnet valves.

💧 Pipe Flow — Head Loss (Darcy-Weisbach)

Calculates frictional head loss and pressure drop for a given flow rate and pipe. Uses iterative Colebrook-White friction factor. (JV pipe-flow-head-loss.xls)

Common μ values: Water 20°C = 0.001, Water 80°C = 0.00035, Hot oil 100°C ≈ 0.003–0.010 Pa·s

💧 Water Flow Rate — Hazen-Williams

Calculates water flow rate for a given pipe size and pressure drop. Water only. Q = 3.763×10⁻⁶ × C × D²·⁶³ × (ΔP/L)⁰·⁵⁴ (JV water-flow-rates.xls)

Velocity check: typical max 3 m/s for isolation valves, 2 m/s for control valves. Enter ΔP = pressure × 9.81 kN/m² per metre of head.

♨ Boiler Capacity Calculator

Converts boiler power to steam output capacity. Used for sizing steam safety valves and blowdown valves. (JV Boiler_Capacity_Calc.xls)

Conversion constants: 1 MW = 3,412,141.3 BTU/hr; 1 boiler hp = 33,445.6 BTU/hr; 1 lb/hr steam ≈ 970 BTU/hr latent heat at ~100°C.

📐 Minimum Pipe Diameter Selector

Finds minimum standard pipe DN for a given flow rate and allowable velocity. Also useful for valve bore selection. (JV friction-factor-pipe-diam.xls)

Standard DN sizes used: 15, 20, 25, 32, 40, 50, 65, 80, 100, 125, 150, 200, 250, 300, 350, 400, 450, 500, 600, 750, 900, 1050, 1200.