Seamless Steel Pipe

Wall Thicknesses – Schedule 40 up to 4.000”

Application of seamless pipe
Low temperature service pipes
Tubes for mechanical and structural
Tubes for fluid transportation
Ship building tubes
Bearing pipes
Line pipes used in sour service
Tubes for pressure services
Pipe for high temperature
Honed tube
Boiler tubes
Heat exchanger tubes
Marine seamless steel pipe
Tubes for mechanical and automobile

Condition on delivery of seamless pipe

Cold-finished/hard (cold-finished as-drawn)
BK
No heat treatment after the last cold-forming process. The tubes therefore have only low deformability.

Cold-finished/soft (lightly cold-worked)
BKW
After the last heat treatment there is a light finishing pass (cold drawing) With proper subsequent processing, the tube can be cold-formed (e.g. bent, expanded) within certain limits.

Annealed
GBK
After the final cold-forming process the tubes are annealed in a controlled atmosphere or under vacuum.

Normalized
NBK
The tubes are annealed above the upper transformation point in a controlled atmosphere or under vacuum.

Manufacturing Process

Billets and coils are delivered to the pipe mill ready to be made into carbon steel pipe. Depending on the capabilities of the pipe mill and the end use of the final product, the casts will be formed into pipe by means of four distinct different manufacturing. Seamless carbon steel pipe has, as its name implies, no longitudinal weld seam. It is, in essence, one solid homogeneous piece of steel. A solid billet is simply heated and then stretched over a series of mandrels until the pipe has achieved its desired diameter and wall thickness.

Cold drawn seamless tube

Cold Drawn Seamless Mechanical Tubing (CDS) is a cold drawn 1026 steel tube. Produced from piercing hot rolled bar stock, the cold drawing process increases the tube's physical properties reducing the cost of machine time. Cold drawn seamless tubing provides a better uniformed OD and ID, enhanced machinability, increased strength, and tighter tolerances compared to hot finish seamless products.

Made from 1026 steel
Meet ASTM A519
Stocked size range: 1.500”OD – 14.000” OD; .250” wall – 1.25” wall
Stocked lengths 17’-24’
Cut to length service available

Hot Finished Seamless Mechanical Tubing (HFS) is a 1020/1026 carbon seamless mechanical steel tube commonly produced from a rotating heated bar and pierced to create a hollow tube. HFS tubing is a cost effective alternative to cold drawn seamless tubing with just a broader tolerance range on the outside diameter (OD) and inside diameter (ID). Hot Finished Seamless mechanical tubing is manufactured to OD and wall dimensions.

HFS tubing is made from 1020/1026 Steel
Meets ASTM A519 & A106 standards
Stocked Size Range: 3.00" OD - 26.000" OD; 0.500" wall - 4.000" wall
Stocked Lengths 17'-40'
Cut to length service available

Packages of seamless pipe

Bundled package

On bundle of steel tube shall be the same in batch number, steel grade and specification.the rest of tubing less than one bundle should be tied into small bundles. The weight of each bundle should be less than 50kg.The max weight cannot exceed 80kg of the bundle If there are special requirements. When the length of the steel tube is greater than or equal to 6m, with at least 8 strapping bands for each bundle, divided into 3 groups and 3-2-3. When the length of the steel tube is less than 6m, and each bundle is tied at least 5 knots and divided into 3 groups, which are 2-1-2.
When the length of the tube is greater than or equal to 3m, and each bundle is tied with at least 3 bands, divided into 3 groups, 1-1-1 showed below

Wooden box package

The wooden box is suitable for cold rolling or cold drawing seamless steel tube, polished hot rolled stainless steel tube. When the outer diameter of steel pipe is greater than or equal 10mm, the maximum weight of the container should be 50kg. When the outer diameter of steel pipe is less than or equal 10mm, the maximum weight of the container should be 30kg.

A seamless pipe is a long strip of steel with a hollow section and no seams around it.

The characteristics of stainless steel seamless pipe: first, the thicker the wall thickness of the product, the more economical and practical it is, and the thinner the wall thickness, the processing cost will increase significantly; secondly, the process of the product It determines its limited performance. Generally, the precision of Seamless Tube is low: uneven wall thickness, low brightness inside and outside the tube, high cost of cutting to length, and pitting and black spots on the inside and outside are not easy to remove; third, its detection and shaping Must be processed offline. Therefore, it embodies its superiority in terms of high pressure, high strength, and mechanical structural materials.

Types of stainless steel pipes: The rolling methods are divided into hot rolling, hot extrusion and cold drawn (rolled) stainless steel pipes. According to the metallographic structure of stainless steel, it can be divided into semi-ferritic and semi-martensitic stainless steel pipes, martensitic stainless steel pipes, austenitic stainless steel pipes, austenitic-ferritic stainless steel pipes, etc.

Manufacturing process of stainless steel seamless pipe:
1. Hot rolling (extruded Seamless Tube): round tube billet → heating → piercing → three-roll cross rolling, continuous rolling or extrusion → stripping → sizing (or reducing) → cooling → straightening → hydraulic test (or flaw detection) → marking → warehousing
2. Cold drawn (rolled) Seamless Tube: round tube blank→heating→perforation→heading→annealing→pickling→oiling (copper plating)→multi-pass cold drawing (cold rolling)→blank tube→heat treatment→straightening → Hydrostatic test (flaw detection) → Marking → Storage.