What is MS Hydraulic Pipe?

MS hydraulic pipe is a precision mild steel pipe designed for high-pressure hydraulic and pneumatic systems. The pipe gets manufactured to tight dimensional tolerances with a smooth internal bore. Every dimension matters when seals and fittings need to hold pressure.

The wall thickness of a hydraulic pipe stays consistent around the entire circumference. The inside diameter holds a tight tolerance for seal contact. The bore surface gets finished smooth enough that fluid flows without excess turbulence. These features let the pipe handle repeated pressure cycles without failure.

Most hydraulic pipes come cold-drawn. This process pulls the pipe through a die, improving both dimensional accuracy and surface finish. Some applications need bright annealed or phosphated surface treatment for corrosion resistance or paint adhesion.

Properties & Features of MS Hydraulic Pipe

The following 4 features of MS hydraulic pipes make it a preferred choice for many applications:

High Pressure Rating

High Pressure Rating

Depending on size and wall thickness, our hydraulic pipes can handle working pressures from 100 bar to over 400 bar. The cold drawing process creates a grain structure that is thick and even. This improves strength against pressure cycling. Choosing the right wall thickness will ensure that your application has a high safety factor.

Precision Tolerances

Precision Tolerances

Tight OD and ID tolerances ensure reliable sealing and easy assembly. Standard tolerance is H8/h8. For critical applications requiring perfect seal contact, H7 tolerance is suitable. This precision eliminates uncertainty when sizing seals and fittings.

Smooth Bore

Smooth Bore

A low surface roughness (Ra ≤ 1.6μm) reduces friction and turbulence in the fluid stream. This improves the system’s performance and its durability. For tough applications, you can get smoother bores down to Ra 0.8μm or better.

Clean Internal Surface

Clean Internal Surface

Rigorous cleaning and degreasing processes remove all scale, rust, and contaminants from the pipe's interior. This prevents particle contamination in the hydraulic fluid, which protects sensitive components like pumps, valves, and actuators from wear and damage. For systems requiring the highest cleanliness standards, pipes can be supplied meeting ISO 16232 or similar cleanliness specifications. This ensures long service life and minimal maintenance.

Applications of MS hydraulic pipes

MS hydraulic pipes are used in the following 4 equipment and systems that move fluid under pressure:

Hydraulic Cylinders

The main part of hydraulic rams and actuators is the cylinder barrel. The pipe must have the right ID for the piston seal to fit and the right wall thickness to hold the pressure. For reliable production, cylinder manufacturers need high-quality pipes.

Construction Machinery

Hydraulic pipes are used by excavators, loaders and cranes to lift and control circuits. These machines work in tough conditions where there is dirt, vibration, and extreme temperatures. The pipes have to be able to handle constant pressure spikes from heavy lifting and digging while still working without leaking for the entire life of the equipment.

Automotive Systems

Hydraulic pipes are used in power steering systems, brake circuits and suspension parts to move fluid safely and accurately. To ensure responsive handling and reliable braking, the pipes must meet strict automotive standards for cleanliness and dimensional consistency. Smooth internal surfaces are critical to minimise pressure drop and maintain system efficiency.

Industrial Machinery

Hydraulic pipes are used in presses, injection moulding machines and automated production lines for accurate force and motion control. These systems need pipes that work well even when they undergo repetitive cycling, and that maintain tight tolerances so they work as expected. The clean insides keep dirt and other contaminants from getting in, which could cause expensive downtime or damage to precision parts.

100% Certified Testing & Documentation

Each of our carbon steel seamless tubes undergoes mandatory testing as per the ASTM/ASME standards. The following tests verify material quality and dimensional conformance:

  • EN 10204/3.1B Certificates
  • Dimensional Inspection Report
  • Surface Finish Report
  • Pressure Test Certificate