Loading the mobile arm pin up cause and the improvement measures

Pin shaft load motor arm external reasons and improvement measures 2020 - 05 - 08 chih-peng liu ( Dragon industry ( Shanghai) Machinery manufacturing co. , LTD. Loader technology center) 1 ZL50C loader in use after 300 h, the movable arm and front frame hinged place outside the two pin of channeling phenomenon. Inspection found that the two pin clamp has been out of shape. If the movable arm pin to continue running outside, will lead to fracture, movable arm pin shaft pin linking piece fall off, can lead to movable arm fall due to lose bearing, seriously affect the safe use of the loader. Movable arm connected to the front frame structure as shown in figure 1. Former frame 1 and movable arm 3 through movable arm pin 7 connection. 4 through the pin shaft fixed bolt clamp lock on the front frame 1 6, so that the movable arm pin shaft fixed on the frame before 1 July. Homework process, the loading motor arm on 3 around the front frame 1 movable arm swing pin 7, movable arm axial force on the moving arm pin 7. Movable arm pin 7 constantly affected by axial force, can cause movable arm pin 7 up trend. Former frame 1 and 6 pin clamp is 0. 05 ~ 0. 25 mm clearance, when the movable arm pin 7 produce greater than zero. 25 mm displacement, and can cause the retaining bolt 4 pin clamp 6 alternating stress is produced. In this long-term under the action of alternating stress, the retaining bolt would create loose, in 4 pin clamp 6 also can cause deformation, thus eventually led to the movable arm outside the pin 7. To solve the problem, the study decided to move the arm structure was improved, and the former frame connection as shown in figure 2, the improved structure concrete improvement measures are as follows: welding screw thread on the front frame 1 9, threaded seat 9 step height more than 6 pin press plate thickness 2 mm. Fixed bolt between 4 and threaded seat 9 add 1 level 8, 8 by Pacific cushion bolt 4 and 9 fastening screw thread. Due to thread a 9 step height more than 6 pin press plate thickness 2 mm, fixed bolt fastening, 4 with threaded seat 9 Pacific cushion 8 with pin clamp with 2 mm gap between each 6 fixed bolt 4 and Pacific pads 8 counter shaft clamp 6 compaction effect, just up the block. So when the movable arm pin 7 under alternating stress, the retaining bolt 4 will not be affected by the alternating stress, so the fixed bolt looseness also won't produce 4, which can prevent the movable arm outside channeling pin 7. According to these measures, improved the loader USES after 1600 h, movable arm pin shaft work is normal, not again appear outside channeling phenomenon, the desired effect. Source: engineering machinery and maintenance 5, 2015