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Understanding and Addressing Track Shoe Breakage in Crawler Cranes
Crawler cranes play a vital role in the construction industry, but track shoe breakage can disrupt operations and lead to costly repairs. In this article, we delve into the causes of track shoe breakage and present practical solutions to prevent such occurrences.
How to deal with the failure of safe unloading of crawler cranes?
Crawler cranes often use pilot-controlled hydraulic systems, which are comfortable to operate and have good micro-movements. The system adopts a pilot control oil circuit safe unloading method to prevent possible dangerous working conditions such as main and auxiliary hoisting hoist overload or truss boom luffing. That is, through the combined action of torque limiter, overload unloading solenoid valve and logic valve or limit switch, over-elevation unloading solenoid valve and logic valve, to ensure that safe unloading can be reliably achieved in the event of overload or over-elevation misoperation. , To prevent accidents. 1, oil pump 2, main valve 3, luffing hoist motor 4. Secondary hoisting winch motor 5. Main hoisting winch motor 6. Overload unloading solenoid valve 7. Over-lift unloading solenoid valve 8, logic valve 9, pilot receiving handle 10, fuel tank A crawler crane carried out a safety experiment during the trial production process and found that during overload or over-tilt operations, although the indicator light on the control room panel has alarmed, all operations can still be continued, indicating the safety of its safety protection device. Safety unloading fails. Analyze this problem, and the failure of the electrical system or the hydraulic system can lead to the failure of safe unloading. So, check from both the circuit and the liquid path. The purpose of circuit testing is to check whether the torque limiter and limit switch can transmit the electrical signal to the unloading solenoid valve while providing the alarm signal of the panel indicator light. If so, the unloading circuit will be connected to achieve safety Unloading, otherwise, safe unloading will fail. According to the schematic diagram, before the torque limiter provides an electrical signal to the unloading solenoid valve, the unloading solenoid valve is normally off, that is, the unloading circuit is disconnected, and once the torque limiter provides an electrical signal to it, the unloading solenoid The valve is energized, reversing, and connecting the unloading circuit. For this reason, disconnect the pipeline (T1 port) on the side of the logic valve, and then found that when the torque limiter does not issue a command, the overload unloading solenoid valve Y1 has no electricity, and the solenoid valve has no reversal and no pressure. The oil flows out, and when the machine enters the overload condition, the valve is energized and hydraulic oil flows out of the pipeline immediately. This shows that the logic command program issued by the torque limiter is normal, and the unloading solenoid valve is also working normally. In the same way, when checking the limit switch that controls the over-elevation unloading and the over-elevation unloading solenoid valve Y2, they work normally. Therefore, the possibility of circuit failure is ruled out. After checking the circuit, check the fluid circuit. First, check the wiring, and there is no error. Finally, focus on the logic valve. It is suspected that the spring of the one-way valve in the logic valve is hard or the diameter of the valve is small, so that the unloading The back pressure of the load oil circuit is relatively large, which causes the unloading oil circuit to be unsmoothed and difficult to unload. Therefore, in the alarm state, the pressure of the port an or bn corresponding to the action was measured and found that the pressure was about 1 MPa, and the main valve only needed a pilot pressure of about 0.6 MPa to open, which proved that the suspicion was correct. It is difficult to unload the load due to the high back pressure.
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YANTAI EVERGROWING IMPORT AND EXPORT CO., LTD.
ADD: A508, NO 133-1 YINGCHUN ROAD, LAISHAN DISTRICT, YANTAI CITY, CHINA
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