Excavator rotary gear ring is broken, the master teaches you how to repair
Oct 18, 2024
1) According to the damage of the gear ring, determine the position of the fixed hole and the damaged section that needs to be replaced, and then cut the section of teeth to be replaced with gas cutting.
(2) According to the parts of the gear ring that need to be repaired, the insert is processed, or the corresponding part of the other old gear ring is cut out a relatively intact gear tooth under the condition of ensuring the pitch, and the groove shape is cut out at the joint.
(3) Determine the position of the insert fixing hole, punch the hole to fix it in the corresponding part of the gear ring, pay attention to ensure the accuracy of the fixed hole position.
(4) In order to ensure that the weld has higher strength and can withstand greater impact and vibration, the junction 507 electrode with a diameter of Φ4mm is selected, and the electrode should be baked at 250 ~ 350℃ for 1h before use.
(5) Using AX3500 DC arc welding machine DC reverse welding, the current is 130 ~ 140A. (1) Preheat before welding, use 2 large gas welding guns to heat the welding surface to about 200℃.
(2) Using the temper weld method, the latter weld plays a tempering role on the previous weld, which is conducive to eliminating the hardened structure generated by the previous weld.
(3) Because of the large groove, when welding the first weld, it should be welded slightly thinner to reduce the melting width and reduce the carbon content of the steel. When welding, the electrode tilts forward about 15°, straight forward, and pay attention to filling the arc pit when the arc is closed to avoid arc pit cracks. After welding, use a small pointed hammer to quickly hammer the weld and both sides to relax the stress until the weld appears dense pitting. Continue welding when the weld cools down to about 200℃.
(4) The welding method of each weld after the first weld is the same as that of the first weld, the electrode can be slightly pendulum, in order to avoid porosity, do not pendulum too large.
(5) In order to eliminate the hardened structure and stress after welding, the weld and both sides are heated to about 600 ~ 650℃ with oxygen acetylene flame, and the heat is kept for 20min, and then the weld is covered with asbestos, hydrated lime powder or dry sand, and the weld is slowly cooled to room temperature.
(6) Polish the weld with the polishing wheel, so that the tooth ring repair is completed. The process of repairing tooth ring with segment insert is simple, the technical requirement is low, the repair time is short and the repair quality is high. The service life of the tooth ring repaired with the old insert is about 1/3 of the life of the new tooth ring, and the service life of the tooth ring repaired with the new insert is equivalent to the life of the new tooth ring. The method can be used to insert the tooth ring repeatedly, and the economic benefit is remarkable.