The technology of repairing and repairing diesel engine is as follows:
1 metal clasp Technology
Metal clasp is a special connector made of high strength alloy material. It is used mechanically to lock the damaged parts to repair. It is mainly used for repair of cracks and broken parts of large castings.
The advantage of metal fastening is that the repaired machine has sufficient strength and good sealing property; the required equipment and tools are simple; the machine parts have no thermal deformation stress; it can be built on the spot. But the process is not suitable for thin wall parts (the thickness is less than 8 mm), and the corrugated trough makes trouble and trouble, and so on.
(1) strong fastening. In the direction perpendicular to the crack or fracture section, the corrugated groove of a certain shape and size is machined. Then the high strength alloy corrugated trough, which is consistent with the shape and wave groove, is inlaid into the groove, and the wave key is riveted at the normal temperature to produce plastic deformation and full groove cavity, with the aid of the flange of the wave bond and the concave part of the corrugated slot. Fasten the two sides of the damaged side into a solid whole. This method is suitable for repairing thin wall parts with a thickness of 8-40 millimeters, with general strength requirements.
(2) strong clasp. On the basis of the technological principle of strong fastening, a bolt with a patch is planted on the crack or broken surface, and a metal seal is formed to achieve the purpose of connecting and sealing.
The screw diameter depends on the distance between the two wave keys, usually 5~8 millimeters, and the spacing between the screws should be as small as possible. The screw material should be the same as the wave bond material; the soft materials such as low carbon steel or copper can also be used for the repair parts with low requirements. The coating glue is usually epoxy resin or phosphoric acid oxide inorganic glue. Screw The screwing depth is the same as the waveform key, and it is tightened to remove the protruding part and smooth. This method is suitable for the repair of the high pressure seal parts, such as the cracks or broken of the cylinder and the pressure vessel.
(3) high grade buckle. It is a hole (such as a rectangle) formed on a repair area perpendicular to a crack or fracture section. Then a reinforced block with the same shape and size is inlaid in a man's hole. A pin or screw is planted on the combination line of the machine and the insert to make half of it on the reinforced block and the other half in the body to get a solid combination. The reinforcing block can be designed to be rectangular, dovetail or cross.
This method is suitable for repairing difficult heavy load and wall thickness parts.
(4) hot buckle. The cracked parts are locked by the heating of the fastener in the cooling process. This method is suitable for the repair of the crack or fracture of the large flywheel, gear and heavy machinery body.
2 additional parts method
Some parts are only partially worn or damaged. When the structure is allowed, the wear parts can be processed, and then a metal sleeve or other insert is set in this part. Finally, it is processed into a standard size. The insert becomes a part in the post repair structure, which is added to the repair process, so this repair method is used. The appended parts method is widely used in maintenance. After attaching parts, it can be replaced after wearing.
3 local replacement method
Some parts are only partially worn or damaged, and other parts are still well or slightly damaged. When the structure is allowed, the surface of the worn parts or the surfaces with serious defects can be removed and the new parts are rewelded. Finally, it is processed to the standard size to repair the parts. The essence of this method is to replace part of the part. It is called a local replacement repair method.
The local replacement method is widely used in the repair of parts, such as the wear of the end of the shaft, the wear of the thread, or the fracture of the shaft end. If the other end is perfect, but the shape is complex, the local repair method can be used.
4 simple polishing and grinding
A simple tool is mounted on the electric drill to polish or grind the metal, and the effect is good.
(I) grinding wheel grinding tool. It is made of 4 pieces of spindle, nut, grinding wheel and thick paper pad. The axis is made of No. 40 steel car, in which the rotation of the M22 * 1.5 thread should be opposite to the hand drill, to prevent the grinding wheel from being grinded. The grinding wheel uses a disc wheel with a diameter of 1011 millimeters. The fixed plane should be added with a paper pad to increase the clamping force and protect the grinding wheel. The axis inside the shaft. The cone hole is matched with the hand drill spindle. It can be used to unload the drill chuck and install the tool. It is mainly used to grind the gear, shaft and other parts with small grinding capacity after grinding. It can be used to grind the workpiece by hand operation, and the drill can be fixed on the tvise and move the workpiece by hand to grind.
(2) the steel wire brush polishing tool. It consists of the heart shaft, nut, splint and wire mesh. The spindle is made of 40 steel car, and the wire net is fixed by nut and splint. The wire mesh is made with a diameter of 0.5 to 0.75 mm. The diameter of the net is about 70 millimeters. This tool can be used for removing the paint and polishing of the outdoor table, the rust removing and scaling of the water tank, and so on. High work efficiency can also reduce the labor intensity of workers.
