GB welded steel pipe
GB welded steel pipe
Welded steel pipe, also called welded pipe, is a steel pipe made by welding or forming a steel plate or strip.
Straight seam welded pipe has simple production process, high production efficiency, low cost and rapid development. The strength of the spiral welded pipe is generally higher than that of the straight welded pipe. It is possible to produce a welded pipe with a large diameter by using a narrow blank, and it is also possible to produce a welded pipe having a different pipe diameter by using a blank of the same width. However, compared with the straight pipe of the same length, the weld length is increased by 30 to 100%, and the production speed is low.
Large diameter or thick welded pipes are generally made directly from steel billets, while small welded pipe thin-wall welded pipes need only be welded directly by steel strips. Then after a simple polishing, the wire can be used.
Welded pipe process
Raw material unwinding - leveling - end shearing and welding - looper - forming - welding - internal and external bead removal - pre-correction - induction heat treatment - sizing and straightening - eddy current testing - cutting - hydraulic inspection - pickling - final inspection (strictly checked) - packaging - shipping.
Standard of GB welded steel pipe
1. Welded steel pipe for low-pressure fluid transportation (GB/T3092-1993) is also called general welded pipe, commonly known as black pipe. It is a welded steel pipe used for conveying general lower pressure fluids such as water, gas, air, oil and heating steam and other purposes. The thickness of the steel pipe is divided into ordinary steel pipe and thick steel pipe; the pipe end form is divided into non-threaded steel pipe (light pipe) and threaded steel pipe. The specification of the steel pipe is expressed by the nominal diameter (mm), and the nominal diameter is an approximate value of the inner diameter. It is customary to use inches, such as 11/2. The welded steel pipe for low-pressure fluid transportation is mainly used as a raw pipe for galvanized welded steel pipe for low-pressure fluid transportation, in addition to being directly used for conveying fluid.
2. Galvanized welded steel pipe for low pressure fluid transportation (GB/T3091-1993) is also called galvanized electric welded steel pipe, commonly known as white tube. It is a hot dip galvanizing (furnace welding or electric welding) steel pipe for transporting water, gas, air oil, heating steam, warm water and other general lower pressure fluids or other purposes. The thickness of the steel pipe is divided into ordinary galvanized steel pipe and thick galvanized steel pipe; the connection end form is divided into non-thread galvanized steel pipe and threaded galvanized steel pipe. The specification of the steel pipe is expressed by the nominal diameter (mm), and the nominal diameter is an approximate value of the inner diameter. It is customary to use inches, such as 11/2.
3. Ordinary carbon steel wire casing (GB3640-88) is a steel pipe used to protect electric wires in electrical installation projects such as industrial and civil construction, installation machinery and equipment.
4. Straight seam electric welded steel pipe (YB242-63) is a steel pipe whose weld is parallel to the longitudinal direction of the steel pipe. Usually divided into metric electric welded steel pipe, welded thin-walled pipe, transformer cooling oil pipe and so on.
5. Spiral-slot submerged arc welded steel pipe (SY5036-83) for pressure-bearing fluid transportation is a hot-rolled steel strip coil for tube blank, which is often spiral-formed and welded by double-sided submerged arc welding for pressure fluid transportation. Spiral seam steel pipe. The steel pipe has strong pressure bearing capacity and good welding performance. It is safe and reliable after various strict scientific tests and tests. The steel pipe has a large caliber, high conveying efficiency, and can save investment in laying pipelines. It is mainly used to transport oil and natural gas pipelines.
6. Spiral seam high-frequency welded steel pipe (SY5038-83) for pressure fluid conveying is a hot-rolled steel strip coil for tube blank, which is often spiral-formed by high-frequency lap welding for pressure fluid transport. Spiral seam high frequency welded steel pipe. The steel pipe has strong pressure bearing capacity and good plasticity, which is convenient for welding and processing. After various strict and scientific inspections and tests, the use is safe and reliable, the steel pipe has large caliber, high conveying efficiency, and can save investment in laying pipelines. It is mainly used for laying pipelines for transporting oil and natural gas.
7. General spiral spiral submerged arc welded steel pipe (SY5037-83) for low-pressure fluid transportation is made of hot-rolled steel strip coil for tube blank, regular temperature spiral forming, double-sided automatic submerged arc welding or single-sided welding method. Submerged arc welded steel pipes for general low-pressure fluid transportation such as water, gas, air and steam.
8. General high-pressure fluid conveying spiral spiral high-frequency welded steel pipe (SY5039-83) is a hot-rolled steel strip coil for tube blank, regular temperature spiral forming, high-frequency lap welding welding for general low-pressure fluid conveying spiral High-frequency welded steel pipe.
9. Spiral welded steel pipe (SY5040-83) for piles is made of hot-rolled steel strip coils, often spiral-formed by double-sided submerged arc welding or high-frequency welding, used for civil engineering structures, wharfs and bridges. Steel pipes for foundation piles.
The main materials used in the national standard welded steel pipe:
Q235A, Q235B, Q235C, 20#, Q345 (16Mn), L245 (B), L290 (X42), L320 (X46), L360 (X52), L390 (X56), L415 (X60), L450 (X65), L485 (X70), L555 (X80).
According to the different welds, the national standard welded steel pipe can be divided into spiral national standard welded steel pipe and straight seam national standard welded steel pipe.
Application
Products are widely used in water engineering, petrochemical industry, chemical industry, power industry, agricultural irrigation, urban construction.
For liquid transportation: water supply and drainage. For gas transportation: gas, steam, liquefied petroleum gas.
For structural use: for piling pipes, for bridges; for piers, roads, building structures, etc.
Specification chart
Straight seam welded pipe specification chart
Spiral welded pipe specification chart
|
Outer diameter
|
wall thickness
|
Welding management theory weight
|
|
21.25
|
2.75
|
1.26
|
|
26.75
|
2.75
|
1.63
|
|
33.3
|
3.25
|
2.42
|
|
42.25
|
3.25
|
3.13
|
|
48
|
3.5
|
3.84
|
|
60
|
3.5
|
4.88
|
|
75.5
|
3.75
|
6.64
|
|
88.5
|
4.0
|
8.34
|
|
114
|
4.0
|
10.85
|
|
140
|
4.5
|
15.04
|
|
165
|
4.5
|
17.81
|
|
219
|
6
|
31.52
|
Spiral welded pipe specification chart
|
specification
|
Wall thickness
|
Weight per meter
|
National standard water pressure value
|
Ministry standard water pressure value
|
|
219
|
6
|
32.02
|
9.7
|
7.7
|
|
7
|
37.1
|
11.3
|
9
|
|
|
8
|
42.13
|
12.9
|
10.3
|
|
|
273
|
6
|
40.01
|
7.7
|
6.2
|
|
7
|
46.42
|
9
|
7.2
|
|
|
8
|
52.78
|
10.3
|
8.3
|
|
|
325
|
6
|
47.7
|
6.5
|
5.2
|
|
7
|
55.4
|
7.6
|
6.1
|
|
|
8
|
63.04
|
8.7
|
6.9
|
|
|
377
|
6
|
55.4
|
5.7
|
4.5
|
|
7
|
64.37
|
6.7
|
5.2
|
|
|
8
|
73.3
|
7.6
|
6
|
|
|
9
|
82.18
|
8.6
|
6.8
|
|
|
10
|
91.01
|
-
|
7.5
|
|
|
426
|
6
|
62.25
|
5.1
|
4
|
|
7
|
72.83
|
5.9
|
4.6
|
|
|
8
|
82.97
|
6.8
|
5.3
|
|
|
9
|
93.05
|
7.6
|
6
|
|
|
10
|
103.09
|
8.5
|
6.7
|
|
|
478
|
6
|
70.34
|
4.5
|
3.5
|
|
7
|
81.81
|
5.3
|
4.1
|
|
|
8
|
93.23
|
6
|
4.7
|
|
|
9
|
104.6
|
6.8
|
5.3
|
|
|
10
|
115.92
|
7.5
|
5.9
|
|
|
529
|
6
|
77.89
|
4.1
|
3.2
|
|
7
|
90.61
|
4.8
|
3.7
|
|
|
8
|
103.29
|
5.4
|
4.3
|
|
|
9
|
115.92
|
6.1
|
4.8
|
|
|
10
|
128.49
|
6.8
|
5.3
|
|
|
630
|
6
|
92.83
|
3.4
|
2.6
|
|
7
|
108.05
|
4
|
3.1
|
|
|
8
|
123.22
|
4.6
|
3.6
|
|
|
9
|
138.33
|
5.1
|
4
|
|
|
10
|
153.4
|
5.7
|
4.5
|
|
specification
|
Wall thickness
|
Weight per meter
|
National standard water pressure value
|
Ministry standard water pressure value
|
|
720
|
6
|
106.15
|
3
|
2.3
|
|
7
|
123.59
|
3.5
|
2.7
|
|
|
8
|
140.97
|
4
|
3.1
|
|
|
9
|
158.31
|
4.5
|
3.5
|
|
|
10
|
175.6
|
5
|
3.9
|
|
|
12
|
210.02
|
6
|
4.7
|
|
|
820
|
7
|
140.85
|
3.1
|
2.4
|
|
8
|
160.7
|
3.5
|
2.7
|
|
|
9
|
180.5
|
4
|
3.1
|
|
|
10
|
200.26
|
4.4
|
3.4
|
|
|
11
|
219.96
|
4.8
|
3.8
|
|
|
12
|
239.62
|
5.3
|
4.1
|
|
|
920
|
8
|
180.43
|
3.1
|
2.5
|
|
9
|
202.7
|
3.5
|
2.8
|
|
|
10
|
224.92
|
3.9
|
3.1
|
|
|
11
|
247.22
|
4.3
|
3.4
|
|
|
12
|
269.21
|
4.7
|
3.7
|
|
|
1020
|
8
|
200.16
|
2.8
|
2.2
|
|
9
|
224.89
|
3.2
|
2.5
|
|
|
10
|
249.58
|
3.5
|
2.8
|
|
|
11
|
274.22
|
3.9
|
3
|
|
|
12
|
298.81
|
4.2
|
3.3
|
|
|
1220
|
8
|
239.62
|
-
|
1.8
|
|
10
|
298.9
|
3
|
2.3
|
|
|
11
|
328.47
|
3.2
|
2.5
|
|
|
12
|
357.99
|
3.5
|
2.8
|
|
|
13
|
387.46
|
3.8
|
3
|
|
|
1420
|
10
|
348.23
|
2.8
|
2
|
|
14
|
417.18
|
3.2
|
2.4
|
|
|
1620
|
12
|
476.37
|
2.9
|
2.1
|
|
14
|
554.99
|
3.2
|
2.4
|
|
|
1820
|
14
|
627.04
|
3.3
|
2.2
|
|
2020
|
14
|
693.09
|
-
|
2
|
|
2220
|
14
|
762.15
|
-
|
1.8
|