BS 1387 Class B Hot Dipped Galvanized Steel Pipe 2 Inch for Water Plumbing

Engineered to deliver outstanding corrosion protection and mechanical reliability for municipal and industrial utility networks, this BS 1387 Class B Hot Dipped Galvanized Steel Pipe is the premier choice for professional water plumbing. Utilizing a 2-inch nominal diameter (60.3mm OD) steel tube manufactured in strict compliance with the BS 1387 Class B (Medium Series) standard, it features a robust 3.6mm wall thickness designed for secure pressure containment.
The pipe undergoes a rigorous hot-dipping process, coating both the interior and exterior in a thick, metallurgically bonded zinc layer. This protective zinc cladding shields the steel base from oxidation and prevents internal rust buildup, ensuring a clean, continuous water supply and exceptional longevity in residential, commercial, and industrial plumbing systems.

Features & Advantages

Thick Hot-Dipped Galvanized Layer: The metallurgical zinc-iron alloy coating provides superior barrier and sacrificial protection against moisture, preventing internal scaling and external rust.

Class B (Medium) BS 1387 Performance: The 3.6mm wall thickness provides an optimal balance of structural strength and mechanical flexibility, perfectly rated for standard water plumbing pressures.

Screwed & Socketed Availability: Can be supplied with precision factory-cut threads to BS 21, complete with protective sockets (couplings) for rapid, tool-friendly on-site mechanical assembly.

Excellent Threading & Weldability: Fabricated from highly malleable carbon steel, facilitating smooth, reliable field threading and fabrication without cracking.

Technical Specifications

Specification Item	Detailed Description
Product Name	BS 1387 Class B Hot Dipped Galvanized Steel Pipe
Standard Specification	BS 1387 (Screwed and socketed steel tubes and tubulars)
Class / Weight Series	Class B (Medium Series - typically color-coded Blue)
Manufacturing Process	ERW base pipe followed by Hot-Dip Galvanizing
Nominal Pipe Size (NPS)	2 Inch (DN50)
Outer Diameter (OD)	60.3 mm (Minimum 59.7 mm – Maximum 60.8 mm)
Wall Thickness (WT)	3.6 mm (0.142 inches)
Galvanizing Standards	EN ISO 1461, BS 729, ASTM A53
Zinc Coating Weight	Typical ≥ 350 g/m² up to 500 g/m² (minimum 50–70 microns thickness)
End Configurations	Screwed and Socketed (Threaded & Coupled to BS 21) or Plain Ends
Standard Length	5.8m, 6.0m, or customized as per container transport limits

Product Applications

Residential & Commercial Water Plumbing: Supplying clean potable water and general utility water within buildings.

Industrial Utility Pipelines: Chilled water lines, cooling tower loops, and low-pressure industrial plumbing.

Automatic Fire Sprinkler Networks: Reliable wet pipe fire sprinkler mainlines and branch lines.

Agricultural & Irrigation Systems: Heavy-duty water conveyance and water distribution loops in farming infrastructure.

Rigorous Quality Control & Manufacturing Process

Our 2-inch BS 1387 Class B galvanized pipes undergo a stringent manufacturing and chemical treating process:

Base Tube Dimensional Inspection: Verifying the outer diameter, wall thickness, and weld seam of the raw ERW steel tubes to ensure compliance with BS 1387 Medium specifications.

Chemical Pickling & Fluxing: Immersing the tubes in an acid bath (pickling) to remove all surface scale and rust, followed by a fluxing treatment to prepare the steel for metallurgical zinc bonding.

Molten Hot-Dip Galvanizing: Dipping the preheated tubes into a molten zinc bath maintained at approximately 450°C, allowing the zinc and steel to form a series of highly corrosion-resistant zinc-iron alloy layers.

Excess Zinc Blowing & Threading: High-pressure steam or air is blown through the interior and exterior of the pipe to clear excess zinc, followed by high-precision BS 21 threading and socket attachment.

Frequently Asked Questions (FAQ)

Q1: What does “Class B” represent in the BS 1387 standard?

A: BS 1387 classifies tubes into three classes based on wall thickness: Class A (Light, color-coded yellow), Class B (Medium, color-coded blue), and Class C (Heavy, color-coded red). Class B (Medium) has a 3.6mm wall thickness for the 2-inch pipe, providing the ideal safety margin and mechanical durability required for standard pressurized water plumbing.

Q2: What is the typical zinc coating thickness for these hot-dipped pipes?

A: In compliance with EN ISO 1461 and BS 729, our hot-dipped galvanizing process delivers a robust zinc coating weight of 350 g/m² to 500 g/m² (which is approximately 50 to 70 microns of dry zinc thickness). This thick layer is far superior to thin electro-plated coatings and ensures decades of protection in damp or underground conditions.

Q3: Are threaded and coupled (screwed and socketed) options available for the 2-inch pipe?

A: Yes, absolutely. The traditional British standard jointing method for BS 1387 plumbing is “Screwed and Socketed” (threaded ends on both sides, with one end pre-assembled with a matching threaded socket/coupling). We can supply these pre-threaded to BS 21 specifications, ready for immediate screw assembly in the field.

Q4: Why choose hot-dipped galvanizing over electro-galvanizing for water plumbing?

A: Electro-galvanizing provides a very thin, cosmetic zinc layer (typically less than 10 microns) only on the exterior. Hot-dip galvanizing immerses the entire pipe in molten zinc, coating both the interior and exterior in a thick, 50-70 micron metallurgical alloy that resists scaling inside and soil corrosion outside, which is mandatory for water carrying pipes.