The impact toughness of high-pressure seamless pipe reflects the resistance of metal to external impact load, generally expressed by impact work (Ak), and its unit is J (Joule).

High-pressure seamless pipe impact test (abbreviated as "impact test") is divided into three types of impact tests at room temperature, low temperature and high temperature due to different test temperatures; according to the shape of the sample notch, it can be divided into "V" shaped notch and "U" There are two types of "shaped notch impact test."

Impact test: Use a high-pressure seamless tube sample of a certain size and shape (10×10×55mm) (with a "U" or "V" notch in the middle of the length direction, and a notch depth of 2mm) to be impacted on the specified testing machine Experiment of breaking from the notch under load.

High-pressure seamless pipe impact absorption work Akv(u)---the work absorbed by a metal pattern with a certain size and shape when it is broken under the action of an impact load. The unit is Joule (J).

The normal temperature impact test temperature of high pressure seamless pipe is 20±5℃; the low temperature impact test temperature range is

The cooling medium used in the low-temperature impact test is generally non-toxic, safe, non-corrosive to metal, and liquid or gas that does not solidify at the test temperature. Such as absolute ethanol (alcohol), solid carbon dioxide (dry ice) or liquid nitrogen atomization gas (liquid nitrogen), etc.