Technical requirements and quality inspection of straight seam pipes

- Dec 09, 2020-

Technical requirements and quality inspection of straight seam pipe According to the standard of GB3092 "welded steel pipe for low pressure fluid transportation", the nominal diameter of welded pipe is 6~150mm, the nominal wall thickness is 2.0~6.0mm, and the length of welded pipe is usually 4~10m. It can be factory-made according to the length of fixed length or multiple length. The surface quality of steel pipe should be smooth, and there are no defects such as folding, cracking, delamination and lap welding.

        The surface of the steel pipe is allowed to have slight defects such as scribes, scratches, misalignment of welds, burns and crusting that do not exceed the negative deviation of the wall thickness, allowing the thickness of the weld to be thickened and the internal weld bead to exist. The welded steel pipe should be mechanical. Performance test and flattening test and flaring test, and to meet the requirements of the standard, the steel pipe should be able to withstand a certain internal pressure, if necessary, carry out a pressure test of 2.5Mpa, keep no leakage for one minute, and allow the use of eddy current testing instead. Hydraulic pressure test, eddy current testing is carried out according to GB7735 "Steel Tube Eddy Current Testing Method".

        The eddy current testing method is to fix the probe on the frame, and the flaw detection and the weld seam are kept at a distance of 3~5mm. The weld is fully scanned by the rapid movement of the steel pipe, and the flaw detection signal is automatically processed and automatically sorted by the eddy current flaw detector. To achieve the purpose of flaw detection, the welded pipe after the flaw detection is cut with the flying saw according to the specified length. After the inverted frame is taken off the wire, the ends of the steel pipe should be chamfered at the ends, and the marks are printed. The finished pipe is wrapped in a hexagonal package and then shipped.

Product Description
sch 40 ASTM A53 /SSAW/LSAW/ERW Welded Black Steel Pipe for building material
Product Name
Spiral Welded Pipe/Sprial Tube/Spiral Steel Tube
6m/9m/12m Or Other Size According To The Contract
Steel Material
Q195, Q215, Q235, Q345 (Chinese Grade. Other Material Can Be Ordered)
Used For Gas, Petroleum, Water ,Oil, Structure And Sewage
Plain or Beveled (Can be Protected By Plastic Pipe Cap)
Bared Or Paint With Oil, Bitumen,1-3 layer PE
(Outside Or Inside Anti-Corrosion Treatment Can Supply)
With Hydraulic Testing, Eddy Current , Infrared or X-Ray Test
Also With Chemical And Physical Property Inspect
Hot Rolled and SAW/ERW/SSAW
Welded Line Type
Section Shape
In Bulk, Or Other Method According To The Contract
Date of Delivery
Less Than 15/20/25/30/40/50/60 Days According To The Quantity
Port of Shipment
Tianjin Xingang,China
We also supply pipe fittings for example screws and flange
Our products are high quality but low price.
Wish you contact us.
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Company Introduction

Cangzhou Steel Pipe Group (CSPG)Co.,Ltd.

No.92 JieFang East Road ,Cangzhou City, Hebei,P.R.China.

CSPG  has more than eighteen years history company which located in Lecong Iron and Steel World, a well-known steel distribution center in China, with superior geographical position and convenient water and land transportation. 

We are a direct-selling manufacturer specializing in the research and development of spiral steel pipes, steel spiral pipes, anti-corrosion steel pipes inside and outside. Since its inception, the company has been guided by a brand-new thinking of steel pipe product market based on the business philosophy of honesty, pragmatism and knowledge-seeking.

1:Do you have OEM service? A: yes, the specifications and models of the products can be customized according to your needs. 
2: are you a trading company or a manufacturer?A: we are a company integrating industry and trade. 

3: How long is your delivery time?A: generally speaking, it takes 15-20 days after receiving the advance payment. The exact delivery time depends on the item and quantity of your order. 

4: where is your factory? May I see the work?A: Changfu road, qinyang city, henan province