The most commonly used method to test the hardness of SA 213 boiler tube is to wipe the edge of the work piece with a file and scrape the surface depth to determine its hardness. The method is not scientific. The hardness tester is very accurate, and it is a common method in modern hardness testing. The most commonly used test method is Rockwell hardness test. Rockwell hardness tester uses diamond to enter the metal depth to determine the hardness of the boiler tube. The greater the depth of entry, the smaller the hardness. The diamond goes deep into the metal and can point out the correct number from the pointer. The number is called Rockwell hardness.


forging
It is a hammer, making metal into a certain shape < forming > method. When SA 213 boiler tube is heated to forging temperature, it can be forged, bent, drawn, shaped and other operations. Most high pressure boiler tubes are heated to fresh cherry red when they are easy to forge.


Brittleness
It is said that the characteristics of high-pressure boiler tubes are easy to crack, cast iron fragile, and even fall to the ground will burst.


Ductility
(Softness) is the permanent deformation of metal due to external deformation. The ductility of high-pressure boiler tubes can be drawn into thin lines.


elastic
It is a kind of high-pressure boiler tube, which is deformed by external force and recovers its performance when the external force is restored to its original state.  Spring steel is a very flexible material.


hardness
It is a metal resistance foreign body into cutting or cutting high-pressure boiler tubes can increase the hardness of the common method is quenching.


exhibition
Also known as plasticity, it is another form of metal ductility or flexibility.  Development is a metal that accepts hammer forging or rolling, and deformation does not destroy properties.


toughness
High pressure boiler tubes can withstand shock or shock. On the contrary, toughness and brittleness.