Calculate bellows-sealed globe valve stem thrust, operating torque and handwheel force — combining DDJGC/XDJGC/GJDC flow models with bellows spring force and piston effect for zero-leakage designs.
Bellows-sealed globe valves combine the complexity of three flow configurations with bellows elastic forces. The DDJGC/XDJGC and GJDC thrust models differ significantly, and bellows spring force (f4/f5) further modifies both opening and closing thrust. This calculator is the only free online tool that handles all three configurations with full bellows force modeling.
DDJGC (coeff 1.15), XDJGC (coeff 1.50) and GJDC (coeff 1.00) — each with its own thrust model.
f4 = kb*(Lb-LGb)/Nb and f5 = kb*LGb/Nb — fully integrated into DDJGC and GJDC thrust formulas.
Uses bellows inner diameter (db_bellows) for piston calculations instead of packing gland diameter.
Built-in database with auto-populated bellows defaults from each thread specification.
Automatic F0/M0 with 30% safety margin, accounting for bellows forces in worst-case scenarios.
Normal and impact rim forces per MSS SP-91 impact factor table.
Choose DDJGC (low-in, DN>=50), XDJGC (low-in, DN<50) or GJDC (high-in-low-out).
Input seat bore d, DN, handwheel D, and pressures P1/P2.
Enter bellows inner diameter, wave count, single-wave stiffness, total stroke and closing extension.
All intermediate forces (with bellows f4/f5), thrust, torque and handwheel forces computed immediately.
Enter your valve parameters below and get instant stem thrust, operating torque and handwheel force results.