Multi-purpose furnace heat treatment furnace heating body failure repair
In the long-term work of the hot body, it will become soft, swell, fall, fall down and overlap, and then melt (melt). In order to make the furnace wire have a certain strength at high temperature and prevent softening, collapse or sag, the structural dimensions of the furnace wire, such as spiral resistance wire, must be designed, and the diameter, pitch and spiral diameter of the alloy element must be paid attention to. The installation of the heating body should be close to the furnace lining, and it should be laid flat on the shelf, leaving its expansion space appropriately. The position of the small hook should be appropriate, usually 400 ～ 600mm, and it can be firmly hooked to prevent lying down. In addition, in order to prevent contact between the furnace wires, a spacer is required. It can be isolated with high temperature resistant materials such as 95 porcelain to prevent the overlap. In particular, the transition between the layer of bricks in the hearth and the layer (when the furnace is built, there is generally a 50mm gap between the bricks and the front and rear walls for turning and installation of the resistance wire). Put on the porcelain tube (the porcelain tube should reach the head). High temperature furnace can not use diatomite brick saw sheet in the middle of the furnace wire. Due to the poor heat resistance of diatomite brick, it can only be used below 900 ℃, it is easy to dissolve and deteriorate in high temperature furnace.
For the wire that has a tendency to sag, check whether the small hook of the wire is functioning (the hook of the resistance ribbon must be built, pressed, plugged, and not loosened), and it can be changed by gas welding or torch baking. Soft, and then restore its original shape and size, as well as wear porcelain tubes in the furnace wire (core rods can be worn in porcelain tubes). If two porcelain pipes are used at the same time, the ends of the porcelain pipes must be close.
The heating body can be directly welded for general broken ends. For those that are severely collapsed and cannot be straightened, and the local over-burning parts are seriously damaged, the method of replacing one section can be used instead of scrapping the entire set because of partial failure. The material, diameter, pitch, and length of the resistance wire for repair welding must meet the original technical requirements. The newly repaired resistance wire must not have defects such as cracks, corrosion, etc., and must be dense and uniform. When using the old resistance wire, the resistance wire must not have obvious uneven thickness, oxidative corrosion, crack deformation and aging and brittleness. The old extraction rod must not have severe oxidation and corrosion.