Production Technology Improving Process of ERW Steel Pipe

Straight seam welded pipe (ERW straight seam welded steel pipe) is formed on the hot rolled plate of the forming machine, the skin effect and proximity effect of the high frequency current, melting of the pipe edge heating to the extrusion roller pressure welding to achieve production. The application of high-frequency resistance welding method in pipeline production in the 1950s has witnessed more and more mature production technology and continuous improvement of product quality in the past decade or so.

​

First of all, in the quality of raw materials, the production of ERW steel pipe has been significantly improved, the composition of the steel design of low carbon, low P, S, micro-alloying; smelting process smelting, ladle refining, vacuum degassing, continuous casting and other new technologies In addition to the ERW controlled rolling and cold rolling process, the technology has enabled the appearance size of the hot rolled steel strips of large and medium caliber ERW steel tubes to be greatly improved in appearance quality, physical properties and chemical properties. The steel pipelines produced by Baoshan Iron and Steel Company, the highest level of hot rolled strip steel in my country, have met the American Petroleum Institute API 5L standard and are at the international advanced level.

Followed by the middle and large diameter ERW molding welding and heat treatment process of the production process to achieve the computer automatic control, high frequency and computer automatic compensation system welding process heat input energy is effectively controlled to prevent welding heat input welding cold caused by low welding heat input and Excessive combustion caused by high energy. The heat treatment temperature control allows the heat treatment process to achieve the best results according to the process requirements, effectively ensuring the quality of the steel pipe welding and heat-affected zone.

In addition, the progress of ERW tube straight seam welded pipe inspection technology has achieved full online or offline ultrasonic or eddy current weld risk damage, and the hydraulic pressure test may be under the supervision of a computer, stress testing and regulatory requirements. The promotion and implementation of the standard and specification APIQ1 ISO9000 series ensure the quality assurance in the whole process of production, inspection, sales and service of medium and large caliber ERW straight seam steel pipes.

In recent years, various countries have been actively adopting ERW straight seam welded pipe and spiral welded pipe seamless pipe in place, in industrialized countries, ERW straight seam pipe diameter Ф610mm less, ERW steel pipe has reached about 70% of the proportion. Our production capacity of ERW Longitudinal also occasion enhanced.

Order--ERW Steel Pipe to UK

Product: ERW Steel Pipe

Standard: API 5L Gr.B

Specification: Ø219.1mm X 6.35mm X 6000mm.                                                       

                        Ø273.1mm X 6.35mm X 6000mm.

                        Ø355.6mm X 7.92mm X 6000mm

                        Ø457.2mm X 7.92 X 6000mm                                                                                           

                        Ø610mm X 9.53 X 6000mm"

Surface: Black Painting

Ends: BE

Quantity: 130.1t

Production Time: 30 DAYS

Destination: UK

Sales Expert: Landry 

Updated Price List for Hot Rolled ERW Pipe on June 14, 2017

Hot Rolled ERW Steel Pipe Price 2017/06/14

Updated Price List for Small Diameter ERW Pipe on June 14, 2017

In Stock ERW Steel Pipe Price 2017/01/07

Updated Price List For In Stock ERW Steel Pipe On JAN,07,2017

Why ERW steel pipe Equipments Are Being Introduced

Why ERW steel pipe Equipments Are Being Introduced

Now, a lot of metallurgical equipments in our country can be designed, manufactured and integrated by ourselves. After China jointly designing with foreign countries and summarizing the experiences and lessons of installation, commissioning, usage, maintenance, and transformation of foreign equipments, our current design has reached a high level. 

China with manufacturing capabilities can design and manufacture the world-class advanced metallurgical equipment, especially the ERW (Electrical Resistance Weld) Steel Pipe equipments under present design condition and environment. Then, why some products, especially for high-producing, high automated advanced continuous rolling pipe equipment units, are still need to be introduced? The main problem is the level of the equipment and stability, namely many accidents, poor stability and more slowly production speed.

There is a big problem that is: domestic equipments are cheap and fast. In order to seek for cheap and fast products, it is easy to reduce design level and manufacturing cost, shorten the design and debugging cycle. Therefore, the level is decreased accordingly. In addition, in order to seek for stability, our large state-owned enterprises are generally not willing to bear the liability for risk. This could be the current reason that domestic equipments can only be introduced among the private enterprises.

In addition, we should also be clear that all the highly automated and advanced equipment with high performance are not only be designed and manufactured. They all need serious debugging, commissioning and certain amount of time to a test run. This is an insurmountable stage and only in this way, domestic equipments can march towards a higher level. ERW Steel Pipe production equipments in China now are the time to enter the international market. Some developing countries, especially those who have the iron ore resources, are considering starting building ERW Steel Pipe, factory in dealing with the global crisis as this is a rare opportunity. 

In Stock ERW Steel Pipe Price 2017/01/01

Updated Price List For In Stock ERW Steel Pipe On November,07,2016

The comparison of ERW steel pipe and LSAW steel pipe

The comparison of ERW steel pipe and LSAW steel pipe

The ERW steel pipe Resistance is high frequency straight seam welded pipe, the English Electric hold Welding, abbreviation abbreviation for ERW, used for transporting oil, gas and vapor liquid object, can meet the requirements of high and low pressure various, currently in the field of conveying pipe in the world occupies a pivotal position.
1, welded pipe refers to the common "submerged arc welding steel pipe," marked "SC" electrical engineering, can be used as water gas pipe can also make the threading pipe, thick.
2, line pipe, wire and tube, thin, with a "T", said can only do threading works.
3, ERW pipe is "high-frequency resistance welding steel tube", unlike ordinary welded pipe welding process, welding seam is composed of steel belt ontology of parent metal melting and mechanical strength than the general welding control. "LSAW steel pipe is the main technique straight seam submerged arc welding steel pipe features: 1 steel tube forming process, the steel plate uniform deformation, residual stress is small, the surface does not produce scratches. Processing of steel pipe diameter and wall thickness of the steel pipe size range, more flexibility, especially in the production of high grade thick wall steel tube, especially in large diameter thick wall pipe has incomparable advantage over other process, can satisfy the requirement of users in the steel pipe specification more; 2 use in the process of the internal and external welding (welding) after welding process, can be in the best position for welding, is not easy to appear the wrong side, partial and incomplete fusion welding defects, such as easy to control the welding quality. 3 for overall mechanical expanding, can effectively improve the size precision of steel tube, and improve the distribution of stress in steel tube, to avoid due to the damage caused by stress corrosion, is advantageous to the field of welding construction at the same time;
4 ,to 9 100% of steel pipe quality inspection, make the whole process of steel pipe production are under effective detection, monitoring, effectively ensure the product quality.
5 ,the whole production line all equipment with the function of the computer data acquisition system networking, realize the data real-time transmission, by the central control room for production.

In Stock ERW Steel Pipe Price 2016/12/24

In Stock ERW Steel Pipe Price 2016/12/24

In Stock ERW Steel Pipe Price 2016/12/20

Updated Price List For In Stock ERW Steel Pipe On December,20,2016

In Stock ERW Steel Pipe Price 2016/12/20

In Stock ERW Steel Pipe Price 2016/12/20

Corrosion Problems of ERW Steel Pipe

ERW steel pipe outer coating of the basic functions,there are two aspects:
First,make the ERW steel pipe surface from electrochemical corrosion,bacterial corrosion protection of soil basic physical media.
Second,resist the soil medium move creep stress,basic mechanical protection method static sterss and abrasion strength and structure and so on.

The basic principles of the outer coating selected city gas pipeline:
a,good insulation properties and mechaniacal properties;
b,good resistance to cathodic disbanding performance;
c,good resistance to water,gas permeability;
d,good chemical resistance properties of soaking and aging;
e,low tempercature and high temperature performance;
f,easy mending and mending;
g,the price is reasonable.

How to Weld for the ERW Steel Pipe in Winter

To ensure that the erw steel pipe in the winter welding perfect follow the following steps:
First, increase the welding current welding, slow down the welding speed, the appropriate increase in the cross-sectional area and length of the weld, if necessary, preheat.
Second, not outside the groove on the base metal to start arc, arc extinction to be filled when the pit.
Third, as far as possible not in low temperature conditions for bending, correction and assembly weldments.
Fourth, preheating before welding, welding process to strictly maintain the interlayer temperature should not be lower than the preheating temperature.
Fifth, the use of low hydrogen or ultra-low hydrogen welding materials.
Six, the entire weld should be finished as far as possible to avoid interruption.

The Difference between ERW Steel Pipe and Seamless Pipe

Nowadays, with quick construction of society and rapid development of technology, more and more different kinds of steel pipes are created, such as welded steel pipe, seamless steel pipe, ERW steel pipe and so on, and more and more steel pipes are needed. In the competitive market of steel pipe, ERW steel pipe, seamless pipe and welded steel pipe are well sold thanks to their specific characteristics.

There are a few aspects of differences between ERW steel pipe and seamless steelpipe. ERW pipe, which is short for electric resistance welding, is used in delivery of liquid, such as fuel, gas and so on, regardless the requirement of pressure, which plays an important role in the conveying tube all over the world, while seamless pipe is a kind of steel pipe shaping square and rectangle and having no seam around with hollow cross-sections, which is used in conveying liquid but also making structural members and machine parts, due to its surprisingly high anti-bending and anti-torque strength and impossibly lightness. All in all, ERW pipe and seamless steel pipe is quite different in use.

What's more, the biggest difference between ERW pipe and seamless steel pipe is that ERW pipe has welding line, which is the same as welded steel pipe, but seamless black steel pipe doesn't have, either does the welded steel pipe. Furthermore, the welding line of ERW pipe is the key to the quality of ERW steel pipe. The more unrecognizable the welding line of ERW pipe is, the higher quality ERW pipe has. As an old saying goes ‘hard work pays off', with scientists' continuous hard study, a huge success in eliminating the welding line of ERW pipe has been achieved. There are two ways to eliminate the welding line: geometric seamlessly and physical seamlessly. Geometric seamlessly is to eliminate the burr both inside and outside while physical seamlessly is to take steps to make base metal and metallographic structure uniform and consistent, which seems more complicate to achieve, however, a ERW pipe without a welding line can be successfully attained through which. Compared with processing technique of ERW pipe, the processing technique of seamless steel pipe is much simpler. There are two entirely different types of processing technique: cold-drawing and hot rolling. Compared with hot rolling, the technological process of cold-drawing is more complicated. Moreover, in the appearance, cold-drawn seamless stainless steel pipe is shorter than hot-rolled one and the wall thickness of cold-drawn seamless stainless steel pipe is generally smaller than the wall thickness of hot-rolled one. What's more, the technological process of hot rolling needs high temperature which reduces the resistance of deformation so that a big deflection is achieved. Generally speaking, the technological processing of ERW pipe and seamless steel pipe are quite different, due to the different appearance.

In general, although ERW pipe and seamless steel pipe both play an important role as well the welded steel pipe do in the construction of society, ERW pipe and seamless API steel pipe has different use and different making progress thanks to their different appearance. Scientists have always been paying a lot to improve their property, which is aimed to make them more multifunctional and to reduce the cost of processing. Maybe one day, ERW pipe and seamless steel pipe will have little differences.

For more information, please visit http://www.shinestar-steel.com

Knowledge of ERW Line Pipe

With the rapid development of economy and the continuous improvement of the energy demand, the pipeline as the oil and gas resources has developed in recent years. A number of medium-caliber ERW line pipe unit was completed and put into operation. ERW line pipe has been widely used in the oil and gas field gathering pipelines, oil and gas Spur. This article will focus on the circumferential residual stress on the impact of ERW line pipe manufacturing process and final product quality and control aspects of the problem.

ERW pipe forming process can be divided into two phases: the first stage of

deformation; the second stage for reducing distortion. In both phases, the steel pipe inner layer is always affected by the circumferential compressive stress and compressive deformation. The outer layer of fine molding of the bending process by weeks to the tensile stress and extension deformation: in the fine shaping and sizing process. Steel outer layer of compressive stress and compressive deformation. And ERW pipes of different specifications, the outer layer of the final strain differences. This shows that the ERW pipe inner and outer layers in the pipe circumferential strain is inconsistent. Stress state and stress the size of change.

Common problems in manufacturing process of ERW line pipe:
(1) ERW line pipe manufacturing process will bend uneven deformation of the pipe week up there is a large residual stress, so take the necessary measures to reduce the negative impact of residual stress on the ERW line pipe manufacturing process.
(2) the study and control of ERW line pipe residual stress should not be confined to the detection and analysis of the residual stress of the final product, required to pipe forming process of ERW pipeline analysis, taken from the perspective of process control measures to reduce ERW pipeline the residual stress of the pipe, reduce the adverse effects of residual stress may cause the quality of ERW line pipe.
(3) Sizing is mainly to ensure the pipe diameter to meet the requirements, the hydrostatic test is to ensure that the density of steel pipe, but for the ERW pipeline in terms of pipe, Is also an important process to reduce the circumferential residual stress.