Home Our Products

  • Our Products
  • Hot Formed Structural Hollow Section
  • Cold Formed Welded Structural Hollow Section

A Steel Pipe Manufacturer Specialized in Structural Hollow Sections

Nakajima Steel Pipe specializes in manufacturing structural hollow sections used for the columns of steel structures. These products meet the emerging need in Japan for steel structures that are predominantly based on the rigid frame structure, requiring steel hollow sections for columns and H-section steel for beams.

We are the only company in Japan that manufactures both high-quality hot formed structural hollow sections for superior quake resistance and cold formed welded structural hollow sections for excellent cost performance.

  • Hot Formed Structural Hollow Section
  • Cold Formed Welded Structural Hollow Section

Patents

Patents in Japan (Excerpt)

Name of Invention
Hot formed process for large square hollow sections
Same as above
Method for improving the material property of the corner portions of large square hollow sections
Method for roll forming large square hollow sections
Method and equipment for forming large square hollow sections
Method and equipment for manufacturing large square hollow sections, including a hot formed process
Method for forming large square hollow sections
Method and equipment for forming large square hollow sections, including a thermomechanical treatment process
Method and equipment for forming large square hollow sections
Method for heat treating large square hollow sections
Method and equipment for manufacturing large square hollow sections, including a hot formed process
Method for manufacturing large square hollow sections that improves the material property of the corner R portion
Method for manufacturing large hot formed square hollow sections that prevents degradation in the material property of the corner R portion
Method for manufacturing large square hollow sections that improves the material property and achieves uniformity in the shape of the corner R portion
Square hollow sections and a related manufacturing method
Method for forming large square hollow sections
Multi-stage heating furnace for structural hollow sections and a multi-stage heating method

Certification and Specification Documents

Click on a title to download a PDF version of a certification or specification document.

Construction material name Steel grade Certification no. Factory
Hot finished structural hollow section

EN10210 S235JRH
S275J0H
S275J2H
S355J0H
S355J2H
S355K2H

0780-CPD-92030 Tenryu-gawa
Cold formed welded structural hollow section

EN10219 S235JRH
S275J0H
S275J2H
S355J0H
S355J2H
S355K2H

0780-CPD-92030 Tenryu-gawa
JIS G 3466 Square hollow sections for general structural purposes STKR400
STKR490
JQ0508074 Tenryu-gawa

Adobe Acrobat Reader must be installed to view these documents.

adobe reader