What Is Black Steel Pipe ?

Black steel pipe is used in applications that do not require the pipe to be galvanized. This non galvanized black steel pipe acquired its name because of its dark coloured iron oxide coating on its surface.

Because of the strength of black steel pipe , it is used for transporting gas and water to rural areas and for conduits that protect electrical wiring and deliver high pressure steam and air. The oil field industry also uses black pipes for piping large quantities of oil through remote areas.

erw black carbon iron schedule 40 steel pipe

Product Name:	astm a53 gr.b erw black carbon iron schedule 40 steel pipe
Size	OD (mm)	21.3mm-355.6mm
	Wall Thickness (mm)	SCH 10,SCH 20………..SCH80
Steel material	Gr A,Gr B
Standard	ASTM A53
Section shape	Round
Type	ERW Pipe
Length	5.8M, 6M, 11.8M, 12M or customized length

Article	ASTM106 black steel pipe
Surface	according to the customer’s acquirement
Length	1m – 6m or as your requirement
W.T.	2-30mm
O.D.	30-250mm
Application	Vehicles, engineering machinery hydraulic chassis, air piping system, etc
Packing	We usually bundle with steel strips ,branding parcel ,wooden box
Terms conditions	CIF,CFR,FOB
Payment	should be 30% in advance by T/T and the balance upon B/L copy or L/C.
Delivery Time	25 days after received the deposit by T/T
Note	we can produce other standard as the customers’ requirement

ABOUT THE TOLERANCE

Size of I.D	I.D Tolerance			Tolerance of wall thickness
Size of I.D	H8	H9	H10	±7.5% >210mm ±10%
30	+0.0330	+0.0520	+0.0840
>30-50	+0.0390	+0.0620	+0.1000
>50-80	+0.0460	+0.0740	+0.1200
>80-120	+0.0540	+0.0870	+0.1400
>120-180	+0.0630	+0.1000	+0.1600
>180-250	+0.0720	+0.1150	+0.1850
>250-315	+0.0810	+0.1300	+0.2100

Mechanical Property of Material:

Delivery condition	cold finished(hard)(BK)		Cold drawn and stress-relieved(BK+S)
Steel grade	Rm MPa	Elongation A5(%)	Rm MPa	ReH MPa	Elonggation A5(%)
St45	≥550	≥5	≥520	≥375	≥15
20#	≥550	≥8	≥520	≥375	≥15
St52 (E355)	≥640	≥5	≥600	≥520	≥14
SAE1026	≥640	≥5	≥600	≥510	≥15
STKM 13C	≥550	≥8	≥520	≥375	≥15
Q345B	≥640	≥5	≥600	≥520	≥14
CK45	≥640	≥5	≥600	≥520	≥10

CHEMICAL COMPOSITION OF MATERIAL

Steel grade	Chemical composition,%
	C	Si	Mn	P	S	Cr
				P	S	Cr
				≤
St45 (20#)	0.17-0.24	0.17-0.37	0.35-0.65	0.035	0.035	0.25
ST52(E355)	≤0.22	≤0.55	≤1.6	0.025	0.025	0.25
SAE1026	0.22-0.28	0.15-0.35	0.6-0.9	0.04	0.05	/
STKM 13C	≤0.25	≤0.35	0.3-0.9	0.04	0.04	/
Q345B	≤0.2	≤0.5	1.0-1.6	0.03	0.03	0.30
CK45	0.42-0.50	0.17-0.37	0.5-0.8	0.035	0.035	0.25

Black steel pipes and tubes can be cut and threaded. Fittings for this type of pipe are of black malleable (soft) cast iron. They connected by screwing onto the threaded pipe, after applying a small amount of pipe joint compound on the threads. Larger diameter pipe is welded on rather than threaded. Black steel pipe is cut either with a heavy-duty tube cutter, cut-off saw or by a hacksaw. It can also get Mild Steel ERW Black Pipes that are extensively used for gas distribution inside & outside of the home, and for hot water circulation in boiler systems. Can also be used in usage in potable water or drains waste or vent lines.

Difference Between Black and Galvanized Pipe

Galvanized Pipe

Galvanized pipe is covered with a zinc material to make the steel pipe more resistant to corrosion. The primary use of galvanized pipe is to carry water to homes and commercial buildings. The zinc also prevents the buildup of mineral deposits that can clog the water line. Galvanized pipe is commonly used as scaffolding frames because of its resistance to corrosion.

Black Steel Pipe

Black steel pipe is different from galvanized pipe because it is uncoated. The dark color comes from the iron-oxide formed on its surface during manufacturing. The primary purpose of black steel pipe is to carry propane or natural gas into residential homes and commercial buildings. The pipe is manufactured without a seam, making it a better pipe to carry gas. The black steel pipe is also used for fire sprinkler systems because it is more fire-resistant than galvanized pipe.

Developments of black steel pipe

Whitehouse’s method was improved upon in 1911 by John Moon. His technique allowed manufacturers to create continuous streams of pipe. He built machinery that employed his technique and many manufacturing plants adopted it. Then the need arose for seamless metal pipes. Seamless pipe was initially formed by drilling a hole through the center of a cylinder. However, it was difficult to drill holes with the precision needed to ensure uniformity in wall thickness. An 1888 improvement allowed for greater efficiency by casting the billet around a fire-proof brick core. After cooling, the brick was removed, leaving a hole in the middle.

Quality Control of black steel pipe

The development of modern manufacturing equipment and inventions in electronics allowed for marked increases in efficiency and quality control. Modern manufacturers employ special X-ray gauges to ensure uniformity in wall thickness. The strength of the pipe is tested with a machine that fills the pipe with water under high pressure to make sure the pipe holds. Pipes that fail are scrapped.

Applications of black steel pipe

Black steel pipe’s strength makes it ideal for transporting water and gas in rural and urban areas and for conduits that protect electrical wiring and for delivering high pressure steam and air. The oil and petroleum industries use black steel pipe for moving large quantities of oil through remote areas. This is beneficial, since black steel pipe requires very little maintenance. Other uses for black steel pipes include gas distribution inside and outside homes, water wells and sewage systems. Black steel pipes are never used for transporting potable water.

History of black steel pipe

William Murdock made the breakthrough leading to the modern process of pipe welding. In 1815 he invented a coal burning lamp system and wanted to make it available to all of London. Using barrels from discarded muskets he formed a continuous pipe delivering the coal gas to the lamps. In 1824 James Russell patented a method for making metal tubes that was fast and inexpensive. He joined the ends of flat iron pieces together to make a tube then welded the joints with heat. In 1825 Comelius Whitehouse developed the “butt-weld” process, the basis for modern pipe making.

Modern Techniques of black steel pipe

Scientific advancement has greatly improved on the butt-weld method of pipe making invented by Whitehouse. His technique is still the primary method used in making pipes, but modern manufacturing equipment that can produce extremely high temperatures and pressure has made pipe making far more efficient. Depending upon its diameter, some processes can produce welded seam pipe at the incredible rate of 1,100 feet per minute. Along with this tremendous increase in the rate of production of steel pipes came improvements in the quality of the final product.