Processes
Edge-Welded Bellows Process
Nickel-Deposited Bellows Process
Edge-Welded Bellows Configuration
K — Bellows Axial Spring Rate. The Ratio of Force to Stroke. (Lbs./In.)
K/C — Spring Rate per Convolution.
Ae — Bellows Effective Area. Equivalent Piston Area That Produces Axial Thrust. (Sq. In.)
A/K — Bellows Pressure Sensitivity. The Amount of Stroke Per Pressure Change. (In./Psi)
P — Convolution Pitch (In.)
Nc — Number of Convolutions
Lf — Free Length of Bellows. (In.)
y — Bellows Stroke or Deflection. (In.)
ΔP — Pressure Differential Across Bellows. (Psi)
ΔV — Fluid Volume Displacement. (Cu. In.)
Deposited Bellows Configuration
Effective Area: Ae = (OD + ID)2 X .1963
Mean Diameter: φm = (OD + ID) / 2
Spring Rate: K = K/C / Nc
Free Length: Lf = Pitch X Nc
Stroke, Comp: y = Comp. Stroke/Conv. X Nc
Stroke, Ext: y = Ext. Stroke/Conv. X Nc
Stroke per PSI: A/K = Ae / Total Spring Rate
Volume Displacement: ΔV = Ae X Total Stroke
Force Output: F = K X y = ΔP X Ae
Span: Convolution Depth = (OD-ID) / 2
Comp. Length (Welded) = 3 X Mat’l Thk. X Nc