Flaring test of steel pipe
Flaring test of steel pipe
Flaring test of steel pipe is a test method to test the deformation behavior of steel tube from radial expansion to specified diameter and to show its defects.
The pipe flaring test is suitable for measuring the plastic deformation ability of circular cross-section pipe flaring with an outer diameter not exceeding 150 mm (non-ferrous metal pipe not exceeding 100 mm) and a wall thickness not exceeding 10 mm. It is suitable for seamless pipe and welded pipe. It is also possible to negotiate with users about non-standard tests for external diameter and wall thickness.
Test Principle: Expanding one end of the pipe with conical plug until the maximum outer diameter of the enlarged end reaches the value specified by the relevant product standards.
Purpose of flaring test
The flaring test is a method to test the deformation performance of the pipe end flaring process. During the flaring test, the top core with a certain taper (such as 1:10, 1:15, etc.) is pressed into one end of the metal pipe sample to evenly expand to the flaring rate (%) stipulated by the relevant technical conditions, and then the flaws such as cracks are checked to determine whether the pipe is qualified or not.
Method of steel tube flaring test
1. According to the relevant technical conditions or the provisions of the agreement between the two sides, different taper of the plug core is selected, and the recommended plug angle is 30, 45 and 60 degrees.
2. tests should generally be carried out within room temperature. The strict temperature test should be controlled at (23 + 5) centigrade.
3. Apply force to the conical plug smoothly to make the end of the steel pipe specimen flared evenly until the required diameter is reached. The maximum external diameter or expansion ratio of the specimen should be specified by the relevant product standards.
4. allow lubrication of the top core. The speed of the plug core pressing into the steel pipe specimen is not stipulated generally, but the plug core pressing rate should not exceed 50 mm/min in case of dispute or arbitration test. The expansion test results shall be evaluated according to the requirements of the relevant product standards. If no specific requirements are specified, the specimens without visible cracks after testing should be assessed as qualified, only slight cracks at the edges of the specimens should not be discarded.
Characteristics of flaring test
1. The expansion test process is similar to that of the material.
2. Generally, the magnitude of stress is not considered, but the surface deformation after stress (such as cracks, cracks, etc.) and some characteristics specified after deformation are used to assess the quality of materials. The test results can reflect the plasticity, toughness and some quality problems of the material.
3. The test method is simple and does not require complex test equipment.
Therefore, the flaring test can be used as the delivery conditions according to the technical agreement. The test results can provide the basis for improving the casting, cold and hot working process of material production enterprises.
