Weld Safety Factors

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Longitudinal Weld Joint Efficiency Factor, E

Weld Safety Factor for Pressure (longitudinal), Wl

Weld Safety Factor for Bending (circumferential), Wc

All weld safety factors are set according to standards and can be selected automatically be clicking .

1 - transverse weld, 2 - longitudinal weld, 3 - fillet weld

Longitudinal Weld Joint Efficiency Factor, E

ASME B31.1: Table 102.4.3 (E factor). Not used for wall thickness check because already included in allowable stress in database. Expansion and sustained allowable stresses Sc and Sh are divided by E

ASME B31.3: Table 302.3.4 (Ej factor). Used for wall thickness check only

ASME B31.4: Table 403.2.1-1 (E factor). Used for wall thickness check only

ASME B31.5: Not used for wall thickness check because already included in allowable stress in database. Expansion and sustained allowable stresses Sc and Sh are divided by E

ASME B31.8: Table 841.1.7-1 (E factor). Used for wall thickness check only

ASME B31.9: Table 902.4.3. Used for wall thickness check 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. Used for wall thickness check only

GB 50251: (j factor). Used for wall thickness check only

GB 50253: Used for wall thickness check only

GB 50316: Table 3.2.5 (Ej factor). Used for wall thickness check only

GB/T 20801: Table 3,4 (F factor). Used for wall thickness check only

Weld Safety Factor for Pressure (longitudinal), Wl

START-PROF use these factors only for checking the wall thicknesses to pressure load in ASME B31.1, ASME B31.3, DL/T 5366.

Wl factors automatically got from material database, you don't have to specify it in input data.

ASME B31.1:

ASME B31.3:

DL/T 5366:

For Russian codes Wc factor should be specified according to code requirements.

Weld Safety Factor for Bending (circumferential), Wc

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)".

START-PROF multiply sustained allowable stress by Wc factor if option "Use Wc factors" is activated in Project Settings. Allowable stress for occasional and expansion loads are not multiplied by Wc.

Wc factors automatically got from material database and equal to Wl factors.