Circular Hollow Section

Circular Hollow Sections are manufactured using the Electric Resistance Welding (ERW) process to provide high strength, durability, and uniform thickness. These pipes are known for their excellent structural integrity, smooth surface finish, and strong resistance to pressure and impact. Their circular design ensures even load distribution, making them highly suitable for various industrial, structural, and general-purpose applications.

Circular Hollow Section
Close view of Circular Hollow Section
Slitting stage
07Slitting
Tube Mill stage
08Tube Mill
Manufacturing Details

Made through controlled, product-relevant stages.

Circular Hollow Sections are manufactured using the Electric Resistance Welding (ERW) process to provide high strength, durability, and uniform thickness. These pipes are known for their excellent structural integrity, smooth surface finish, and strong resistance to pressure and impact. Their circular design ensures even load distribution, making them highly suitable for various industrial, structural, and general-purpose applications.

  1. 07
    Slitting

    The levelled steel coils are processed through high-precision slitting machines where they are cut longitudinally into specific widths according to the required pipe and tube dimensions. The slitting process is carried out with strict dimensional tolerances to ensure uniform strip width and edge quality. Accurate slitting contributes significantly to proper tube formation, welding consistency, and overall product quality in subsequent manufacturing stages.

  2. 08
    Tube Mill

    In the tube mill section, slit steel strips are gradually formed into round, square, or rectangular tubular shapes using advanced forming rolls and automated machinery. The open edges of the formed sections are welded continuously using the Electric Resistance Welding (ERW) process, which produces strong, uniform, and reliable weld joints. The tube mill operation is carefully controlled to maintain dimensional accuracy, structural integrity, smooth weld finish, and superior mechanical performance of the finished pipes and tubes.

  3. 09
    Hydro Testing

    After tube formation, the manufactured pipes undergo hydrostatic pressure testing to verify their strength, leak-proof performance, and pressure-bearing capability. During this process, the tubes are filled with water under controlled high pressure to detect any leakage, weakness, or manufacturing defects. Hydro testing ensures compliance with industrial safety standards and guarantees reliable product performance under operating conditions.

  4. 16
    Finishing & Packaging

    The finished pipes and tubes are carefully bundled, packed, labeled, and secured using suitable packaging methods to prevent physical damage, moisture exposure, and handling defects during storage and transportation. Proper packaging ensures safe delivery, efficient inventory management, and product protection throughout the supply chain until final dispatch to customers.

Explore the complete 16-stage process
Approved product range

Size & thickness availability

Highlighted cells show the wall thicknesses available for each section size. Final availability is confirmed against quantity, finish and the approved supply requirement.

Available thickness
Circular Hollow Section size and wall-thickness availability chart
NB in mm Outer diameter in mm Wall thickness (mm)
0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.20 2.50 3.00 3.20 3.60 4.00
15 21 Not available Available Available Available Available Available Available Available Available Not available Not available Not available Not available
20 26 Not available Available Available Available Available Available Available Available Available Not available Not available Not available Not available
25 33 Available Available Available Available Available Available Available Available Available Available Not available Not available Not available
32 42 Available Available Available Available Available Available Available Available Available Available Available Not available Not available
40 48 Not available Available Available Available Available Available Available Available Available Available Available Available Not available
50 60 Not available Available Available Available Available Available Available Available Available Available Available Available Not available
65 76 Not available Not available Not available Available Available Available Available Available Available Available Available Available Not available
80 88 Not available Not available Not available Not available Available Available Available Available Available Available Available Available Available
100 114 Not available Not available Not available Not available Available Available Available Available Available Available Available Available Available
Certified Quality

Quality backed by certified systems.

ISKCO maintains certified management systems and supplies product ranges against applicable Indian Standards. Requirement-specific documentation is confirmed with the supply team.

MS Strips
IS 10748
Round MS / GI
IS 3601 · IS 1239 · IS 1161
Square & Rectangular MS / GI
IS 18573 · IS 4923
Testing Method

Quality starts before pipe forming.

Incoming MS billets and prepared MS strips are checked before they move into the product-specific manufacturing route.

01

MS Billets

  • Chemical analysis
  • Spectrometer test
  • Hardness test
  • Dimension test
  • Surface inspection
  • Weight verification
02

MS Strips

  • Chemical analysis
  • Tensile strength
  • Thickness & width check
  • Surface quality inspection
  • Weight verification
From material to dispatch

See how every stage connects.

Explore Our Process