Description
Steel Water and Gas Pipes (WGP) are general-purpose welded pipes designed for the construction of water supply, heating, gas supply, and other utility networks. They are one of the most common types of pipe products in housing and utilities.
Production Technology

The manufacturing process includes the following stages:
1.    Strip Preparation: Steel strip (skelp) made of ordinary quality carbon steels is uncoiled and straightened.
2.    Forming: In forming stands, the strip is gradually rolled into a pipe of round cross-section.
3.    Welding: The edges are joined by electric welding:
o    Furnace Welding – thermal method without filler materials.
o    HF Electric Welding – for pipes of increased accuracy.
4.    Calibration and Cooling: The pipe is calibrated to achieve precise dimensions.
5.    Threading: Cylindrical threads are cut on the pipe ends for connection.
6.    Applying Protective Coating: Pipes may be galvanized for corrosion protection.

Characteristics and Assortment
•    Nominal Bore (DN): from 6 to 150 mm
•    Outer Diameter: from 10.2 to 165 mm
•    Wall Thickness:
o    Light – 1.8-4.0 mm
o    Ordinary – 2.0-4.5 mm
o    Reinforced – 2.5-5.5 mm
•    Length: from 4 to 12 meters
•    Thread: cylindrical on both ends

Advantages
•    High Mechanical Strength and resistance to water hammer
•    Low Cost compared to other pipe types
•    Easy Installation using threaded connections
•    Heat Resistance – withstand high temperatures
•    Versatile Application in various systems
•    Durability (especially galvanized versions)

Areas of Application
•    Water Supply: cold and hot water supply for buildings
•    Heating Systems: radiator heating, heating mains
•    Gas Supply: gas distribution systems inside buildings
•    Steam Lines: steam heating systems
•    Construction: fencing structures, scaffolding, frames
•    Mechanization: shafts, axles, mechanism components

Normative Documentation (GOST Standards)
The main standard regulating the production of WGP pipes:
GOST 3262-75 – "Steel water and gas pipes. Technical specifications"
•    Defines the full assortment of sizes
•    Establishes three groups by wall thickness: light, ordinary, reinforced
•    Regulates mechanical properties and steel grades
•    Defines requirements for thread and manufacturing quality
•    Establishes acceptance and testing rules
Key Parameters according to GOST 3262-75:
•    Material: steels St1-St4 according to GOST 380
•    Manufacturing Types: without anti-corrosion coating (black) and galvanized
•    Thread Presence: with or without thread
•    Length: measured (4-12 m) and non-measured (1.5-9 m)