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Longitudinal Weld Joint Efficiency Factor, E
Weld Safety Factor for Pressure (longitudinal), Wl
Weld Safety Factor for Bending (circumferential), Wc
Weld safety factors are assigned
according to applicable design
codes. Apply automatic
factor selection by clicking .
1 - transverse weld, 2 - longitudinal weld, 3 - fillet weld
ASME B31.1: Table 102.4.3 (E factor). Not used for wall thickness verification (already included in allowable stress values). Expansion and sustained stress allowables Sc and Sh are divided by E.
ASME B31.3: Table 302.3.4 (Ej factor). Applied for wall thickness verification only.
ASME B31.4: Table 403.2.1-1 (E factor). Applied for wall thickness verification only.
ASME B31.5: Not used for wall thickness verification (already included in allowable stress values). Expansion and sustained stress allowables Sc and Sh are divided by E.
ASME B31.8: Table 841.1.7-1 (E factor). Applied for wall thickness verification only.
ASME B31.9: Table 902.4.3. Applied for wall thickness verification only.
EN 13480, EN 13941: "Joint Coefficient, Z" p. 4.5
BS PD 8010: "weld joint factor, e", 6.4.3.1
CSA Z662: "Joint Factor, J" 4.3.5.1
ASME B31.12 IP:
ASME B31.12 PL:
DL/T 5366: Table 6.1.2-2. Applied for wall thickness verification only.
GB 50251: (φ factor). Applied for wall thickness verification only.
GB 50253: Applied for wall thickness verification only.
GB 50316: Table 3.2.5 (Ej factor). Applied for wall thickness verification only.
GB/T 20801: Table 3,4 (F factor). Applied for wall thickness verification only.
PASS/START-PROF applies these factors only for pressure-based wall thickness verification per ASME B31.1, ASME B31.3, and DL/T 5366.
Wl factors are automatically retrieved from the material database; manual input is not required.
ASME B31.1:
ASME B31.3:
DL/T 5366:
For Russian codes, specify Wc factors according to code requirements.
ASME B31.1 102.4.7: "The designer is responsible to assess application of weld strength reduction factor requirements for welds other than longitudinal and spiral, as applicable (e.g., circumferential welds)."
ASME B31.3 302.3.5 (e): "The designer is responsible for the application of weld joint strength reduction factors to welds other than longitudinal and spiral (helical seam) (e.g., circumferential)."
PASS/START-PROF multiplies sustained allowable stress by Wc factor when "Use Wc factors" is enabled in Project Settings. Allowable stresses for occasional and expansion loads remain unaffected.
Wc factors are automatically retrieved from the material database and default to Wl factor values.