Cores are used to Form internal cavities in the casting and Improve mould surfaceand used to Form a part of a green sand mould
core is a device used in casting and moulding processes to produce internal cavities and reentrant angles .
The core is normally a disposable item that is destroyed to get it out of the piece
The welding process used to join the ends of two pipes of uniform cross-section, is
Upset butt welding is a welding technique that produces coalescence simultaneously over the entire area of abutting surfaces or progressively along a joint, by the heat obtained from resistance to electric current through the area where those surfaces are in contact