This International Standard specifies the classification, dimension and appearance, performance and test methods for ceramic weld backing. It also specifies marking, packaging and storage. This International Standard is applicable to designing, manufacturing, testing and accepting ceramic weld backing that are to be used in the double side form with single side weld, such as arc welding, gas welding, vertical gas welding and submerged arc welding, and the shaping structural steel welding end for carbon steel, stainless steel, aluminium alloy and copper alloy and so on.