Damage form and repair method of gear of reduction gear
Most gear drives transmit power as well as motion. In the process of transmission, under the action of load, if there is a gear broken tooth surface damage and other phenomena, resulting in the loss of gear normal working ability, called gear transmission failure.
The main forms of gear failure are: gear fracture, tooth surface pitting, tooth surface bonding, tooth surface plastic deformation.
Because the purpose of the reducer is different, the structure is different, and the gear is in different parts of the reducer, the treatment method is also different. Common methods are as follows:
Most of the gear damaged, do not use the method of repair to repair, but to control a certain scrap standard, over the standard will be replaced by a new gear, for the gear did not exceed the scrap standard, can use a scraper or oilstone to remove the tooth surface burr, replace with new lubricating oil to achieve the purpose of reducing damage. The standard of replacement shall be determined according to the purpose and relevant technical standards of the reducer.
The damaged pinion is replaced. For circular speed over 8 m/s and helical gear wear should be replaced in pairs, for large modulus, large gear should be replaced by a combination of repair. The partial broken teeth of large modulus gear can be surfacing welding by gas welding and then processed into accurate tooth shape by tempering. Large gear wear, the use of displacement repair effect is very good, that is, in the repair using high displacement drive, machining gear, change the tool and wheel blank relative position, so that the displacement repair effect is very good; That is to say, high displacement transmission is adopted during repair. When machining the gear, the relative position of the cutter and the wheel blank is changed so that the main parameters (modulus m, pressure a, number of teeth z) of the gear are unchanged. Same as the original gear. What is changed is the size of the crown circle or the root circle is increased correspondingly, and the size of the tooth thickness part is changed. In the transmission of a pair of large and small gears, the pinion usually adopts the positive displacement, the tooth root becomes thicker, the strength and the service life enhancement, the tooth number is also few also may avoid following to cut. Big gear with negative displacement, tooth root strength is weakened, but because the original strength of the big gear is higher, the impact is not large, can make the two gear strength and service life close.