LSAW Pipe Hydrostatic Test

LSAW pipe Hydrostatic test is the most common way used for LSAW pipe inspection. A hydrostatic test is a way in pressure vessels can tested for strength and leaks. Pressure vessels like pipelines, plumbing, gas cylinders, boilers, and fuel tanks.

LSAW Pipe Hydrostatic Test is an important part of LSAW manufacturing. Includes filling the pipe with water, which may dyed to aid in visual leak detection. And pressurization of pipe to the specified test pressure. Pressure tightness can tested by shutting off the supply valve. And seeing if there is a pressure loss.

Hydrostatic Test Machine
Hydrostatic Test Machine

The location of a leak can be visual found more easy if the water contains a colorant. Using the hydrostatic test helps ensure the safety standards. And durability of a vessel over time. Manufactured LSAW steel pipes are initial qualified using the hydrostatic test.

Inspection of pressure vessels for transport and storage of gases. It is very important as such pipes can explode if they fail under pressure.

LSAW Pipe Hydrostatic Test Requirements

Test pressures for LSAW steel pipe with D≤457mm (18.000 in), will held for not less than 5 seconds. Test pressures for weld pipe with D>457mm(18.000 in) must held for not less than 10 seconds.

For threaded and coupled pipe. The test must applied with the couplings made up power-tight if agreed. Except that pipe with D>323.9mm (12.375 in) many tested in the plain-end condition.

For threaded pipe furnished with couplings made up handling-tight. The hydrostatic test must made on the pipe in the plain-end, threads only. or coupled condition unless a specific condition specified in the PO.

Verification of Hydrostatic Test

To ensure that every length of pipe tested to the required test pressure. Each tester, except those on which only continuous welded pipe tested. Must equip with a recording gauge that can record the test pressure. And the test duration for each length of pipe. Or must equipped with some positive and automatic. Or interlocking device to prevent pipe from classified as tested. Until the test requirements (pressure and duration) have met.

Such records or charts must be available for examination. It examed at the manufacturer’s facility by the purchaser’s inspector, if applicable.

Test Pressure

The pipe shall withstand the hydrostatic test without leakage through the weld seam or the pipe body. The hydrostatic test pressure, P, expressed in megapascals (pounds per square inch), for plain-end pipe shall be determined using Equation P=2St/D, with the results rounded to the nearest 0,1 MPa (10 psi): where

LSAW Steel Pipe Hydrostatic Test
LSAW Steel Pipe Hydrostatic Test
  • ‘S’ is the hoop stress, expressed in megapascals (pounds per square inch), equal to a percentage of the specified minimum yield strength of the pipe, as given in Table below;
  • ‘t’ is the specified wall thickness, expressed in millimeters (inches);
  • ‘D’ is the specified outside diameter, expressed in millimeters (inches).

We take the hydrostatic test for 100% pipes under API 5L specification. We are a professional Steel Pipe mill. And we will do our best to support high quality longitudinal submerged arc welded pipe for you.