Today let’s see the Tests and Inspections stipulated in API 5L Specification.
No matter the PSL 1 or PSL2, the standard requires the manufacturer or supplier to test the pipes as following:
- Tensile Properties Test;
- Hydrostatic Test;
- Bend Test;
- Flattening Test;
- Guided-bend Test.
But the CVN Impact Test is just for PSL2 Pipe, this test needs to prepare the samples to test the pipe body and pipe weld and HAZ.
The DWT Test also just required the PSL2 pipe, and just test the size above 20” (including 20”)
Another important thing of the contract is the inspection frequency on the technical document, it will influence the delivery time and supplier cost, so we will introduce part of items to you. For the PSL1 there we need to notice:
- Product analysis needs to one analysis per heat of steel;
- Tensile Test, includes pipe body and needs once per test unit, but some customer will request to test it once per 400PCS or less quantity, this need to pay attention because if the pipe is small or the thickness is thin, there will add some extra test and increase the inspection cost;
- Hydrostatic Testing, Visual Inspection, Wall Thickness Measurement, need to test each pipe;
There has some extra test which didn’t mention in PSL1 but have a requirement in PSL2:
- On PSL2, the pipes need do CVN test, the frequency is once per test unit of pipe with the same cold-expansion ratio
- DWT Impact test, for the size ≥508mm (20inch）
Compared to the PSL1 and PSL2, the inspection frequency is much strict than PSL1. If you want to change it to meet your purchase requirement, you can mark on the technical documents to discuss it with the supplier.