Bar/Wire Wrapped Steel Cylinder Pipes With Mortar lining and Coating (Including Specials)
2002 Edition

Per the standard's Clause 5.1.1 and Table 1, the minimum wall thickness and cement mortar lining thickness vary with pipe diameter as follows:

• For diameters 250-400 mm: wall thickness minimum 40 mm, lining thickness minimum 15 mm.
• For 500-800 mm: wall thickness minimum 45 mm, lining thickness minimum 20 mm.
• For 900-1000 mm: wall thickness minimum 45 mm, lining thickness minimum 20 mm.
• For 1100-1600 mm: wall thickness minimum 50 mm, lining thickness minimum 22 mm.

Wall thickness is calculated as half the difference between average outside and inside diameters. Tolerances allow wall thickness not to be less than design thickness by more than 5% or 5 mm, whichever is greater. Internal diameter tolerances also vary with pipe size, ensuring dimensional accuracy and effective corrosion protection.

The pipes use steel complying with Indian Standards such as IS 2062 for structural steel and IS 432 parts 1 and 2 for mild steel and hard-drawn wire reinforcement. Cement mortar lining follows IS 455, IS 8112, IS 1489, and IS 12330 for various cement types, ensuring adequate bonding and durability. Aggregates must conform to IS 383. Protective coatings adhere to standards like IS 2074 and IS 10289. These materials collectively guarantee the pipes meet strength, corrosion resistance, and performance requirements under specified conditions.

Bar or wire reinforcement is helically wrapped around the cured mortar lining with a center-to-center spacing not exceeding 50 mm and not less than the bar diameter. The wrapping is performed while maintaining a controlled tensile stress between 50 and 70 MPa on the reinforcement. Ahead of the wire, a cement slurry is applied at a rate of at least 0.5 liters per square meter to ensure proper bonding. These measures ensure structural reinforcement meets the specified strength and durability criteria.

Testing includes hydrostatic pressure tests where the test pressure is calculated based on pipe diameter, cylinder thickness, and material stress limits. Pipes are subjected to a 3-minute pressure test ensuring no leaks or cracks. Welds undergo dye penetrant or hot oil inspection as per IS 3658. Coatings, whether bituminous or epoxy, are inspected for integrity and suitability for potable water where applicable. Sampling protocols and acceptance criteria govern batch testing to ensure compliance with all specifications.

Purchasers are required to specify design parameters including maximum internal working pressure, site and factory test pressures, and any surge pressure considerations. Installation details such as trench dimensions, depth of cover, backfill material and density, bedding type, and expected ground loads must be provided. Additionally, purchasers should specify the type of cement for lining and coatings, whether bituminous or other protective coatings are needed, and intended pipe application to ensure the pipes are manufactured to meet operational and environmental requirements.