Table 1-Authorized Materials
4130 | Percent |
Carbon | 0.28/0.33. |
Manganese | 0.40/0.60. |
Phosphorus | 0.040 max. |
Sulfur | 0.040 max. |
Silicon | 0.15/0.35. |
Chromium | 0.80/1.10. |
Molybdenum | 0.15/0.25. |
Table 2-Check Analysis Tolerances
Element | Limit or maximum specified (percent) | Tolerance (percent) over the maximum limit or under the minimum limit | |
Under minimum limit | Over maximum limit | ||
Carbon | Over 0.15 to 0.40 incl | .03 | .04 |
Manganese | To 0.60 incl | .03 | .03 |
Phosphorus1 | All ranges | .01 | |
Sulphur | All ranges | .01 | |
Silicon | To 0.30 incl | .02 | .03 |
Over 0.30 to 1.00 incl | .05 | .05 | |
Chromium | To 0.90 incl | .03 | .03 |
Over 0.90 to 2.10 incl | .05 | .05 | |
Molybdenum | To 0.20 incl | .01 | .01 |
Over 0.20 to 0.40, incl | .02 | .02 |
1 Rephosphorized steels not subject to check analysis for phosphorus.
S = PD / 4tE
Where:
S = wall stress in pounds psi;
P = test pressure prescribed for water jacket test, i.e., at least 2 times service pressure, in psig;
D = outside diameter in inches;
t = minimum wall thickness in inches;
E = 0.85 (provides 85 percent weld efficiency factor which must be applied in the girth weld area and heat affected zones which zone must extend a distance of 6 times wall thickness from center line of weld);
E = 1.0 (for all other areas).
S = [P(1.3D2 + 0.4d2)] / (D2 - d2)
Where:
S = wall stress in pounds psi;
P = test pressure prescribed for water jacket test, i.e., at least 2 times service pressure, in psig;
D = outside diameter in inches;
d = inside diameter in inches.
49 C.F.R. §178.58