Precision casting production tray, basket, stents and other heat treatment equipment, can appear sometimes casting defects such as surface crack, some tiny crack can repair by welding repair defects:More than 90% of the casting manufacturers choose to weld to solve encountered in the production of casting defects.Weld repair for the metal filling material (match the casting material is used for welding materials), welding repair place basic can achieve standards of performance, and the operation is simple, of high efficiency and weld repairs by many manufacturers the recognition and trust.Are many on the market at present, welding machine, applied in defect repair, generally has the following kinds: electric welding machine, cast iron, cast steel welding repair themselves with traditional way.Advantages: repair defects, high efficiency.Disadvantages: solder joints on high hardness after welding, internal stress, prone to cracks, general need annealing heat treatment can meet the requirements of processing.And because of welding conditions, internal easy to produce the secondary defects such as porosity, slag.