Chemical Composition

Technical requirement

A) The Chemical & Mechanical Composition for 37Mn. should be as follow: (%)

		C	Si	Mn	P	S	P+S
37 Mn	Min.	0.30	0.10	1.35	-	-	-
	Max.	0.38	0.35	1.70	0.020	0.02	0.03

(a) W.T. Tolerance: -0/+15%; O.D. Tolerance: ±1%

(b) NDT: Each pipe shall be inspected by UT.

(c) Mechanical properties guaranteed by tube manufacturer after Heat treatment in Lab of tube manufacturer

Min. Value
Tensile Strength	735 N/mm2
Yield Strength	570 N/mm2
Elongation	Not less than 15%
Hardness Test Value	220 – 270 BHN and
Impact Test Individual	– 28 j/cm² minimum. Mean of 3–35 j/cm² min.
Test at	– 50 deg C as per ISO 11439

B) The Chemical & Mechanical Composition for 34CrMo4. should be as follow: (%)

		C	Si	Mn	P	S	Cr	Mo	P+S
34CrMo4	Min.	0.30	0.10	1.50	-	-	0.90	0.15
	Max.	0.37	0.40	0.80	0.020	0.010	1.20	0.30	0.025

(a) W.T. Tolerance: -0/+15%; O.D. Tolerance: ±1%

(b) NDT: Each pipe shall be inspected by UT.

(c) Mechanical properties Minimum guaranteed required mechanical property to be achieved after Heat treatment in Lab of tube manufacturer is as below

Min. Value
Tensile Strength	830 N/mm² (MPa), Maximum 950 N/mm² (MPa)
Yield Strength	705 N/mm²
Elongation	Not less than 14%;
Hardness	Value range: 240 ~ 295 BNH
Impact:	Value-Individual –32 j/cm² min. Mean of 3–40 j/cm² min
Test at	– 50 deg C as per ISO 11439

C) The Chemical & Mechanical Composition for 34CrMo4. should be as follow: (%)

		C	Si	Mn	P	S	Cr	Mo	Ni	P+S
34CrMo4	Min.	0.30	0.10	1.40	-	-	0.90	0.15	0
	Max.	0.37	0.40	1.00	0.020	0.010	1.20	0.30	0.15	0.025

(a) W.T. Tolerance: -0/+15%; O.D. Tolerance: ±1%

(b) NDT: Each pipe shall be inspected by UT.

(c) Mechanical properties Minimum guaranteed required mechanical property to be achieved after Heat treatment in Lab of tube manufacturer is as below

Min. Value
Tensile Strength	928 N/mm² (MPa), Maximum 1100 N/mm² (MPa)
Yield Strength	785 N/mm²
Elongation	Not less than 14%;
Hardness	Value range: 266 ~ 330 BNH
Impact:	Value - Individual –32 j/cm² min. Mean of 3 – 40 j/cm² min
Test at	– 50 deg C as per ISO 11439