In the field of mining, construction and demolition projects, the crushing hammer, as the core equipment of the excavator, has been plagued by hydraulic system failures and structural component deformation problems caused by improper use. Recently, the Construction Machinery Research Institute and a number of host factories released the ‘Crushing Hammer Standard Operation Technical Guide’, which reveals through systematic experimental data: more than 68% of the hydraulic system failure originated from improper operation of crushing hammers, and the scientific use of the structural components can be used to extend the life of more than 40%.

一、Five key measures for hydraulic system protection  

1. Double filtration guarantee  

Install high-precision oil return filter element (recommended β value ≥200), together with the main hydraulic filter element to form a double protection. The after-sales service director of Sany Heavy Industry pointed out that ‘the special oil return filter element for the crushing hammer must be replaced every 500 hours, and the hydraulic oil replacement cycle should be shortened to 70% of the regular working conditions.’

2. Accumulator configuration revolution  

Adopting high-quality crushing hammers with nitrogen accumulators can reduce hydraulic shock by 35%. XCMG's latest test shows that the main pump failure rate of the accumulator model dropped by 61% compared with the regular model in 2,000 hours of continuous operation.

3. Throttle control law  

It is recommended to keep the throttle at 1600-1800rpm for 20 tonnes equipment. Liugong experimental data show that the temperature rise rate of hydraulic oil under full throttle state is 2.3 times higher than that of medium throttle, and the abnormal temperature rise will lead to 400% faster aging of seals.

4. Oil seal replacement standard  

Establishment of ‘600 hours preventive replacement + real-time monitoring’ dual mechanism. Maintenance cases of Hyundai Heavy Industries show that the pollution index of the main valve group of a crushing hammer with delayed oil seal replacement is 17 times higher than that of normal equipment.

5. Air Strike Protection Technology  

Installation of intelligent runaway protection device, when the sensor detects 3 consecutive runaways, it automatically cuts off the oil circuit. Komatsu's latest PC300-11 has included this technology as standard equipment.

 二、 Structural parts protection three-dimensional operation specification  

1. Mechanical angle control  

Keep the chisel rod perpendicular to the crushing surface, and keep 10-15cm stroke buffer space for the bucket cylinder. Caterpillar's actual measurement data shows that when the bucket lever is completely retracted, the impact load of the structural parts increases by 2.8 times.

2. Rotary operation ban  

Lateral impact can be up to 4.6 times that of forward impact. According to Hitachi Construction Machinery maintenance report, the probability of boom weld cracking is increased by 83% as a result of non-compliance with slewing operation.

3. Prohibition of boom use  

It is forbidden to peck with the boom down. Volvo tests show that this operation will generate more than 5 times the static load impact force within 0.2 seconds, directly threatening the life of the main pin of the boom.

三、Trends in industry technology upgrades  

At present, John Deere has developed an automatic mode of crushing operations, real-time adjustment of pump flow and engine speed through the ECU; Doosan introduced an intelligent stress monitoring system, which can be automatically shut down when the structural component stress exceeds the limit. China Construction Machinery Industry Association Secretary General Su Zimeng stressed: ‘With the development of electronic control and hydraulic technology, the penetration rate of intelligent protection system is expected to exceed 60% in the next three years.’

Experts recommend: In addition to standardised operation, the establishment of ‘every 50 hours structural parts flaw inspection + every 200 hours of hydraulic system contamination testing’ preventive maintenance system. Through technological upgrading and management optimisation of the two-pronged approach, can significantly extend the service life of the equipment, reduce the comprehensive use of the cost of more than 30%.