JIS G3455 Carbon Steel Pipes for High Pressure Service

JIS G3455 Carbon Steel Pipes for High Pressure Service

 

1. Scope

This Japanese Industrial Standard specifies the carbon steel pipes, hereinafter referred to as the "pipes" , used for high pressure service at an approximate maximum temperature of 350℃

 

Remarks

1. With the previous agreement of the manufacturer, the purchaser may designate part or all of the supplementary quality requirements Z2, Z3 ,Z4 and Z5 specified in this text.

Appendix Z 2: Elevated Temperature Yield Point or Proof Stress

Appendix Z 3: Ultrasonic Examination

Appendix Z 4: Eddy Current Examination

Appendix Z 5: Charpy Impact Test

 

 

2. The units and numerical values given un { } in this Standard are based on the International System of Units (SI) and are appended for informative reference.

Further, the traditional units accompanied by numerical values in this Standard shall be converted to the SI units and numerical values on Jan. 1, 1991.

 

 

 

2. Grade and Designation
Steel Grade: STS 370 ,STS 410  ,STS 480

The pipe shall be classified into three grades and their letter symbols shall be as given in Table 1

Letter symbol of grade	(Informative reference) Traditional symbol
STS 370	STS 38
STS 410	STS 42
STS 480	STS 49

 

 

 

3. Method of Manufacture

Appearance shall be as follows:

3.1 The pipe shall be manufactured from killed steel by the seamless process

3.2 The pipe shall be subjected to the heat treatment specified in Table 2. The heat treatment other than those specified in Table 2 shall be agreed upon by the purchaser and the manufacturer.

Letter symbol of grade	Hot-finished seamless steel pipe	Cold-finished seamless steel pipe
STS 370	As manufactured. However, low temperature annealing of normalizing may be applied, as necessary.	Low temperature annealed of normalized
STS 410
STS 480	Low temperature annealed of normalized

 

 

3.3 When required by the purchaser, the pipe may be furnished with a bevel end (2)

Note (2)Unless otherwise specified, the shape of the bevel end shall be as shown in Fig. 1.

 

4. Chemical Composition

 

Table 3 Chemical Composition Of JIS G3455 Carbon Steel Pipes

Grade	Chemical Composition %
	C	Si	Mn	P	S
STS 370	0.25 max.	0.10~0.35	0.30~1.10	0.035 max.	0.035 max.
STS 410	0.30 max.	0.10~0.35	0.30~1.40	0.035 max.	0.035 max.
STS 480	0.33 max.	0.10~0.35	0.30~1.50	0.035 max.	0.035 max.

 

 

5. Mechanical Properties

Tensile Strength, Yield Strength or Proof Stress and Elongation

 

Table 4 Mechanical Properties Of JIS G3455 Carbon Steel Pipes

Letter symbol of grade	Mechanical Properties
	Tensile strength	Yield strength	Elongation %
	kgf/m㎡  {N/ m㎡}	kgf/m㎡  {N/ m㎡}	No.11 and No.12 test pieces	No. 5 test pieces	No. 4 test piece
			Longitudinal	Transverse	Longitudinal	Transverse
STS370	38 {373}min	22{216} min	30 min	25 min	23 min	28 min
STS 410	42{412}min	25{245} min	25 min	20 min	19 min	24 min
STS 480	49{481} min.	28{275} min.	25 min.	20 min.	17 min.	22 min.

 

 

Remarks

1. When the tensile test is carried out for No. 12 of No. 5 test piece for the pipe under 8mm in wall thickness, the minimum value of elongation shall be obtained by subtracting 1.5% from the values of elongation given in Table 3-2 for each 1 mm decrease in wall thickness, and rounding off to an integer in accordance with JIS Z 8401 Examples of calculation are given in Informative Reference Table.

 

2. The value of elongation given in Table 3-2 shall not be applied to the pipe whose nominal outside diameter is under 40 mm. However, the value of elongation shall be recorded.

 

 

Informative Reference Table 4-1.

Examples of Elongation Values Calculated for No. 12 Test Piece (Longitudinal) and No. 5 Test Piece (Transverse) for pipes under 8 mm in Wall Thickness

Letter symbol of grade	shape of test piece	Elongation value relating to wall thickness %
		Over 7mm to and excl.8mm	Over 6mm to and excl7mm	Over 5mm to and excl.6mm	Over 4mm to and excl. 5mm	Over 3mm to and excl. 4mm	Over 2mm to and excl. 3mm	Over 1mm to and excl. 2mm
STS 370	No12 test piece	30	28	27	26	24	22	21
	No5. test piece	25	24	22	20	19	18	16
STS 410 STS 480	No12 test piece	25	24	22	20	19	18	16
	No5. test piece	20	18	17	16	14	12	11

 

 

 

5.2 Flatness

When tested in accordance with 9.3, the pipe shall not generate flaws of cracks on its wall surface.

In this case, the distance between the two plates shall be in accordance with the following formula:


 

Where

H : distance between flattening plates (mm)

t : wall thickness of pipe (mm)

D : outside diameter of pipe (mm)

e : constant individually defined for each grade of pipe, 0.08 for STS 38 0.07 for STS 42 and STS 49

 

5.3 Bending

For the pipe whose outside diameter is 50mm of smaller, the purchaser may specify the bending test instead of the flattening test. In the test of 9.4, the pipe shall be free form

the occurrence of flaws or cracks on its wall surface. In this case, the pipe shall be bent through 90ⅹ around an inside radius that is 6 times its outside diameter.

 

 

6. Hydrostatic Characteristic of Nondestructive Characteristic

The pipe shall be tested in accordance with 9.5 and the resulting hydrostatic characteristic of nondestructive characteristic shall conform to either of the following two. The preference for which of them shall be left to specification by the purchaser or to the discretion of the manufacturer.

 

6.1 Hydrostatic Characteristic (Applicable to the end of 1990) When a hydrostatic pressure that is specified by the purchaser, of in the absence of that specification, the values given in Attached Table 1 is applied, the pipe shall withstand is without leakage, In this case, the purchaser, may specify a value of pressure lower or higher than those given in

 

Attached Table 1.

In a hydrostatic pressure test designated by the purchaser, a test pressure exceeding either the value of P calculated from the following formula or 200kgf/Р{196bar} shall be agreed upon by the purchaser and the manufacturer. In this case, the hydrostatic test pressure shall be expressed in each 5 kgf/Р {4.9 bar} and its multiples, and in calculation.the value P in the following formula shall be obtained to the number of units and rounded off to the nearest 5kgf/Р{4.9 bar}.

 

P=200st / D

Where

P: test pressure [ kgf/Р{10 -1 bar( 2 )}

t: wall thickness of pipe (mm)

D: outside diameter of pipe(mm)

s: 60% of the minimum value of yield point or proof stress specified in Table 3-1 [kgf/mm 2 {N/mm 2 }]

 

Note (1) 1bar = 10 5 Pa