RSP : Pipes

Pipe is a term generally used to designate a long hollow body used for conducting gases or liquids such as water, fuel, gas, steam, oil etc. Rourkela Steel plant’s pipe mill produces two types of pipe viz. Electric Resistance Weld (ERW) in 8-5/8" outer diameter to 16" outer diameter sizes and Spiral Welded (SW) pipes in 18" outer diameter to 64" outer diameter sizes.

Both the ERW and SW pipe plants at RSP are authorised to produce line pipes with the API monogram under American Petroleum Institute standard 5L. API pipes are exclusively used for transmission of gas and petroleum products.

Pipes (both ERW and SW) other than API specifications are supplied in IS 3589, commercial quality and works tested to customers' specifications.

Pipes to IS 3589 grades are certified for hydrostatic test pressure, chemical and physical properties and are generally produced under the supervision of the plants' own internal quality control. These are used for erection, drainage, water supply, structural and mechanical uses, pilings, handling of coal and other solids in pulverised and powdery conditions.

Commercial quality pipes are arisings during production of API or IS 3589 grade pipes. These pipes are certified to hydrostatic test pressure equivalent to API-5L-Gr A.

Common Grades: IS 3589 (Fe 330 and Fe 410), Commercial Quality, API 5L PSL-1 (Grades A, B, X42/46/52/56/60/65/70) and API 5L PSL-2 (Grades A, B, X42/46/52/56/60/65/70).

Product Range

Wall Thickness		ERW Outer Diameter		SW Outer Diameter*
Inch	mm	Inch	mm	Inch	mm
0.188	4.8	8 5/8 10 3/4	219.1 273.1
0.219	5.6	8 5/8 10 3/4 12 3/4 14	219.1 273.1 323.9 355.6	18-24	457-610
0.250	6.4	8 5/8 10 3/4 12 3/4 14 16	219.1 273.1 323.9 355.6 406.4	18-32	457-813
0.281	7.1	8 5/8 10 3/4 12 3/4 14 16	219.1 273.1 323.9 355.6 406.4	18-48	457-1219
0.312	7.9	8 5/8 10 3/4 12 3/4 14 16	219.1 273.1 323.9 355.6 406.4	18-64	457-1626
0.344	8.7	8 5/8 10 3/4 12 3/4 14 16	219.1 273.1 323.9 355.6 406.4	18-64	457-1626
0.375	9.5	8 5/8 10 3/4 12 3/4 14 16	219.1 273.1 323.9 355.6 406.4	18-64	457-1626
0.406	10.3			18-64	457-1626

Note:  

(1) ERW Pipes in API specification can be supplied with wall thickness of max 7.1 mm (0.281")

(2) Other thickness within the range can be produced for both ERW & SW Pipes

(3) For SW Pipes thickness above 10.3 mm up to 12.7 mm can be produced through negotiation

* The standard outer diameter of SW Pipes are 18", 20", 22", 24", 28", 30", 32", 34", 36", 38", 40", 42", 44", 46", 48", 52", 56", 60", 64". Pipes in other diameters can be supplied as per mutual agreement.

Length

ERW Pipe: In random length of 6.2 to 12.3 metres, usually supplied with plain bevelled edges, bevelled angle being 30⁰ (+5⁰, - 0⁰) with a root face of 1.6 ± 0.8 mm

SW Pipe: In random length of 7.5 to 13 metres, usually supplied with plain bevelled edges, bevelled angle being 30⁰ (+5⁰, - 0⁰) with a root face of 1.6 ± 0.8 mm

IS: 3589 Electrical Welded Steel Pipes

For Water and Sewerage (Salient Points)

Grade	Chemical Composition					Mechanical Properties
	C % max	Mn % Max	P % max	S % max	CE	YS MPa	UTS MPa min	Elongation % min
Fe 330	0.16	1.20	0.040	0.040	-	195	330	20
Fe 410	0.20	1.30	0.040	0.040	0.45	235	410	18
Fe 450	0.25	1.20	0.040	0.040	0.45	275	450	12

Tolerances

1) Outer Diameter -	± 0.75%
2) Wall Thickness -	ERW ± 10 %
	SWPP + 20%, - 12.5%
3) Straightness - Deviation from straightness not to exceed 0.2% of the total length of each pipe.

Ends
Unless otherwise agreed, end shall be bevelled to an angle of 30⁰ +5⁰, - 0⁰ measured from a line drawn perpendicular to the axis of the pipe.

Hydraulic Pressure Test
Each pipe shall be hydraulically tested at the manufacturers' works. The maximum test pressure will be 60% of the specified min YS as per

P = ST/D, where
	P=Hydraulic test pressure in Mpa
	S=Min YS
	T= Specific thickness in mm
	D= Specific outside diameter in mm.
However, the maximum test pressure to be 5 Mpa.

API-5L Specifications for Line Pipe
(Salient Points)

Grade & Class	C % maxa	Mn% maxa	P% min	P% max	S% max	Other
PSL-1 Welded
A	0.22	0.90		0.030	0.030
B	0.26	1.20		0.030	0.030	b,d
X 42	0.26	1.30		0.030	0.030	c,d
X46, X52, X56	0.26	1.40		0.030	0.030	c,d
X60e	0.26	1.40		0.030	0.030	c,d
X65e	0.26	1.45		0.030	0.030	c,d
X70e	0.26	1.65		0.030	0.030	c,d
PSL-2
B	0.22	1.20		0.025	0.015	b,d
X42	0.22	1.30		0.025	0.015	c,d
X46, X52, X56	0.22	1.40		0.025	0.015	c,d
X60e	0.22	1.40		0.025	0.015	c,d
X65e	0.22	1.45		0.025	0.015	c,d
X70e	0.22	1.65		0.025	0.015	c,d
X80 e	0.22	1.85		0.025	0.015	c,d

Note:

(1) For each reduction of 0.01% below the specified maximum carbon content, an 
increase of 0.05% above the specified maximum manganese content is permissible, 
up to a maximum of 1.5% for grades X42 through X52, up to a maximum of 1.65% for 
grades higher than X52 but less than X70, and up to 2.00% for grades X70 and higher.

(2) Columbium (niobium), vanadium, titanium, or combinations thereof may be used by 
agreement between purchaser and manufacturer.

(3) Columbium (niobium), vanadium, titanium, or combinations thereof may be used at the discretion of the manufacturer.

(4) The sum of columbium (niobium), vanadium and titanium contents shall not 
exceed 0.15%

(5) Other chemical compositions may be furnished by agreement between the purchaser 
and manufacturer, providing that the limits of Note d and the tabular limits for 
phosphorous and sulphur are met.

Tolerances

For diameter of welded, non-expanded pipes

Size (Outer Diameter)	Tolerance
Pipe Body
2 3/8 " to <20"	± 0.75%
20" - 36"	+ 0.75%, - 0.25%
Above 36"	+ 6.35 mm, - 3.20 mm
Pipe Ends
£ 10 3/4"	- 0.4 mm, + 1.59 mm
> 10 3/4"	- 0.79 mm, + 2.38 mm

 For wall thickness

 

	Grade B or lower	Grade X42 and higher
< 20"	+ 15%, -12.5%	+ 15%, - 12.5%
£ 20"	+ 17.5 %, -12.5%	+ 19.5%, - 8 %

Note:

1. Chemical composition over and above specified API composition to be as per mutual agreement.

2. Supplementary requirements of API 5L as per mutual agreement.

3. Rust preventive varnish coating and end protectors on pipe ends can be provided as per mutual agreement.

4. Pipes in PSL-2 can be supplied only as per mutual agreement.