Testing of Tubes
Published:2013-07-07 14:36:16    Text Size:【BIG】【MEDIUM】【SMALL

Types of tests and documentation

By testing the proving is done which proves that the properties of tubes are identical to the requirements of the order and the relevant standards.

The process is divided into three parts:
- Determine the type of test (EN 10021, EN 10204)
- Determine the type of inspection document (EN 10204)
- Selection of individual tests (specifically TDP)

The individual parts are interconnected and there can not be any combination thereof. Custom testing is set up by TDP standards for the individual types of tubes.

Nonspecified testing

- Contains only mandatory tests according to the relevant standards
- The test samples do not have to come from their own supply
- The test room does not have to be independent of the tube treatment plant

The specified testing

- In addition to mandatory testing it includes additional optional tests
- Samples of the tubes are out from delivery, their number is set up by standard 
- The test room has to be independent of the tube treatment plant


- Required by the individual standards of TDC
- Optional agreed when ordering tubes from selection according to standards

Quality - TR 1, TR 2 depends on:
- Chemical composition (Al content)
- Mechanical property values (bending impact test)
- Type of tubes test (specified and nonspecified testing)

Test category 1 and 2 depends on:
- Setting up of the standard
- Chemical composition (carbon and alloy steel)
- The possible options when ordering tubes (for C steels)

Categories differ from each other mainly by demand for non-destructive testing of tubes and possibly the selection of optional tests.

Documents pertaining to testing

Overview of types of certificates according to EN 10204 depending on the type of testing:

Nonspecified testing
- company conformation (from the manufacturer, without the test results)
- company certificate (a certificate from the manufacturer based on the nonspecified testing)

Specified testing 
- company testing certificate, test results based on the nonspecified testing. In this type of testing this is issued when the manufacturer does not have an independent test room. If the test room is independent, instead of issuing this certificate, the 3.1.B. certificate must be issued
- Acceptance test certificate 3.1.A
- Acceptance test certificate 3.1.B
- Acceptance test certificate 3.1.C
- Acceptance test certificate 3.2

Own tests are divided into groups

- Value of the chemical composition of steel: the cast, the product
- Dimensional checks 
- Mechanical properties: tensile, hardness, impact bend test
- Technological tests: flattening, flaring, flanging, bending, ring test
- Impermeability: pressure, non-destructive methods
- Non-destructive testing (eddy current, stray flux, ultrasound) longitudinal defects, transverse defects duality
- Further testing (metallography, corrosion resistance, etc.).
Precision Seamless Steel Tube Manufacturer