Gear pump hydraulic system of the fast repair method 2)

electric arc spraying technology to repair of the gear pump, arc spraying principle and characteristics of arc spraying technology in close to a material, equipment and application of a few years has developed rapidly, its working principle is to spray two wire electrode melting, arc spraying in the hole during the repair of the gear pump, cylinder sleeve, gear shaft and the pump shell uniform wear and scratches sleeve length. , between high hardness appropriate use, strong, binding, good wear-resistant arc spray repair process. 。 Electric arc spraying technology: surface - - - spray adhesive coating preparation work before coating - cooling - at the bottom of the craft work. Spraying process, the requirements of the workpiece, no pollution, no rust, rough surface, even, preheating temperature is just right, and uniform and firm, the work is smooth layer to the bottom of the hot melt adhesive material particles, reliable, good wear resistance and corrosion resistance. Coating quality and the quality of the surface treatment and coating process has much to do, therefore, choose the appropriate surface treatment and coating process is very important. In addition, the spray process, and use the thin metal coating, or copper plating surface adjacent to the spraying part of the hook. The improvement of the cleanliness and roughness of the surface pretreatment coating in base material of basic power. In spraying, the basic surface cleaning, degreasing and surface roughness and other process is an important process in the process of the coating. First response to spray some gasoline, acetone degrease treatment and file, fine sandpaper, abrasive layer and the oxide layer, for relieve fatigue, it exposed metal color. Then, roughed up and roughed up, provide the surface stress, increase the area and clean the surface coating, coating and base to reduce the pressure cooling, coating internal stress relaxation, for the bonding strength increased. Sand blasting is the most commonly used in the process of the coarsening, sand, for a good hard, quartz sand, corundum selection, etc. After the fresh surface roughness can be easily oxidized, or the impact of environmental pollution, thus timely spraying, if more than hours will have to reposition the rough handling. 2 to differences in surface coating and substrate preheating temperature shrinkage stress of surface coating, coating cracking and peeling. Preheat the substrate surface can reduce and avoid the adverse effect. Preheat temperature is unfavorable and exorbitant, in order to avoid substrate surface coating and substrate bonding strength oxidation. Preheat temperature is commonly - ℃, general neutral flame. (3) spray adhesive coating spraying follow-up work to provide a clean, rough surface spray coating of metal film layer, so as to improve the bonding strength of coating and substrate and the bottom of the shear strength to promote. Chromium is generally used in iron nickel alloy based adhesive materials. Spraying process parameters choice of the main principles, in order to improve the bonding strength of coating and matrix. In relative speed of the spray gun and parts than the flame propagation speed, speed, larger thickness, coating wire to speed, power and other parameters arc common decision. Between the gun and distance on the surface of the workpiece in millimeters. Other regulatory parameters arc spraying equipment and the decision of the spraying material, from the spray characteristics. (4) layer of paint job. Should be connected with a wire brush to remove surface sediment at the bottom, then spraying work immediately. Material is carbon steel and low alloy wire, coating with high wear resistance, and the price is low. The wearing parts, coating thickness should be the number of allowances and other related factors, Diameter shrinkage, the clamping deviation, uniform diameter, amount of spray coating, etc. ) Sure. 5] after spraying the workpiece cooling temperature is not high, can direct air cooling.