Seamless Steel Tube Manufacturer ASTM A106 GRB Steel Seamless Pipe

What is Seamless pipe

Seamless pipe is a long steel bar with a hollow section and no joints around it. 

General seamless steel pipe production process can be divided into two kinds of cold drawing and hot rolling, cold rolled seamless steel pipe production process is generally more complex than hot rolling, the tube billet first to carry out three roller continuous rolling, extrusion after sizing test, if the surface does not respond to the crack after the round tube to be cut by the cutting machine, cutting the growth of about one meter blank. 

Then enter the annealing process, annealing with acidic liquid pickling, pickling should pay attention to whether there is a large number of bubbles on the surface, if there is a large number of bubbles, indicating that the quality of the steel pipe can not meet the corresponding standards.  

Product introduction

The appearance of cold-rolled seamless steel pipe is shorter than that of hot-rolled seamless steel pipe, the wall thickness of cold-rolled seamless steel pipe is generally smaller than that of hot-rolled seamless steel pipe, but the surface looks brighter than that of thick-walled seamless steel pipe, the surface is not too rough, and the caliber is not too much burr.  The delivery state of hot-rolled seamless steel pipe is generally delivered after hot rolled heat treatment.  

Hot rolled seamless steel pipe after the quality inspection to go through the staff's strict manual selection, after the quality inspection to carry out the surface oil, and then followed by a number of cold drawing experiment, hot rolling treatment to carry out the test of perforation, if the perforation enlargement is too large to be straightener.  After straightening, it is sent to the flaw detection machine by the transmission device for flaw detection experiment, and finally labeled, formatted and placed in the warehouse. 

Handle design

Seamless pipe production process

The production process of seamless steel pipe is divided into the following steps: round tube billet → heating → perforation → three-roll skew rolling, continuous rolling or extrusion → stripping → sizing (or reducing) → cooling → straightening → hydraulic test (or detection) → marking → storage.  Seamless steel pipe is made of steel ingot or solid tube billet perforated into capillary tube, and then hot rolled, cold rolled or cold drawn made.  

Seamless steel pipe is mainly divided into: hot-rolled seamless steel pipe, cold-drawn seamless steel pipe, cold-rolled seamless steel pipe, 

Our product features

The difference between Seamless pipe and welded pipe

1, in terms of appearance, the difference between seamless steel pipe and welded pipe is that there are welding ribs in the inner cavity of welded steel pipe, and there is no seamless splicing.  

2, seamless steel pipe working pressure is higher, welded steel pipe is generally 10 MPa, and now welded steel pipe has seamless splicing solution.  

3, seamless steel pipe is formed in a cold rolling.  Welded pipe must be produced after electric welding welding, generally have spiral welding and direct welding.  Smaller diameter welded pipe mostly use straight seam welding, large diameter welded pipe is mostly the use of spiral welding, spiral welded pipe and straight seam steel pipe welding method is the same, but the straight seam welded pipe will inevitably have a lot of T-weld, so the probability of missing welding is also greatly increased, and the weld metal at the T-weld is often in a three-way deformation state, increasing the possibility of cracking.  The characteristics of the seamless steel pipe are better, and the natural price is higher. 

Advantages of Seamless pipe 

1, seamless steel pipe light weight, its weight is only 1/5 of square steel.   

2, seamless steel pipe corrosion resistance acid, alkali, salt and atmospheric environment corrosion, high temperature resistance, good impact resistance and fatigue resistance, do not need regular maintenance, effective service life of more than 15 years;   

3. The tensile strength of seamless steel pipe is more than 8-10 times that of ordinary steel, and the elastic modulus is better than that of steel, with excellent creep resistance, corrosion resistance and shock resistance;   

4, seamless steel pipe mechanical properties, easy machining, etc.;   

5. Seamless steel pipe is highly elastic, reused in mechanical equipment, no memory, no deformation, and anti-static. 

The application range of Seamless Pipe

Seamless steel pipe according to the use of different, thick wall seamless steel pipe and thin wall seamless steel pipe.  Seamless steel pipes are widely used. 

1, general purpose seamless steel pipe according to the material, rolled by ordinary carbon structural steel, low alloy structural steel or alloy structural steel.  For example, seamless pipes made of low carbon steel such as No. 10 and No. 20 are mainly used as transportation pipelines for steam, gas, liquefied gas, natural gas, various petroleum products and various other gases or liquids;  45, 40Cr and other medium carbon steel seamless pipe, mainly used to manufacture a variety of machine accessories and pipe accessories. 

2. Seamless steel pipes for general use are also supplied according to chemical composition and mechanical properties, and are supplied according to hydraulic test.  Seamless steel pipes subjected to fluid pressure should be guaranteed to pass the hydraulic pressure test. 

3, special purpose seamless pipe for boiler, geological exploration, bearing, acid resistance and so on.  Such as petroleum geological drilling pipe, petrochemical cracking pipe, boiler pipe, bearing pipe and automobile, tractor, aviation high-precision structural steel pipe.  Structure with seamless steel pipe, mainly used in general structure and mechanical structure.  Its representative material (grade) : carbon steel 20, 45 steel;  Alloy steel Q345, 20Cr, 40Cr, 20CrMo, 30-35CrMo, 42CrMo, etc. 

Product delivery time

As for the delivery time, it can be controlled by the customer.

Because we are a physical factory and cooperate with many large steel mills in China, the time error can be controlled within about 3 days, and we provide free warehousing service