On April 11, 2017,the after-sales department of our company received a call from a construction site in Pakistan,Karachi,the principal of the construction site,said the failure occurred while using the refurbished cip concrete pump that purchased from our company last year: A pump truck 37m,the maximum pressure is 21 Mpa after the main system pressure-out,tighten the main overflow valve and the main pump constant pressure valve adjustment the screw,the phenomenon is still as before.

Troubleshooting:

1,Remove the main relief valve cartridge valve‘s value element, checked and didn't find any abnormal situation, in order to exclude the fault, after fitted with a new one ,found pressure can only be transferred to the 21 Mpa,therefore, it can eliminate the failure of main relief valve’s value element.

2, As there was no equipment to test main oil pump of constant pressure valve if there is a failure, so the processing more wafer blocked pieces (it’s the same size with the cartridge ofthe main valve),using the blocked pieces close off the cartridge, loosen the screw of constant pressure valve, after pressure-out again, adjust constant pressure valve slowly,the pressure can be up to 34 Mpa, it can eliminate the main oil pump failure.

3. When the main oil pump and the main overflow valve core are normal, it is suspected that the DT1 electromagnetic commutation valve of the main overflow valve has internal leakage, and the system pressure returns to normal after replacing the DT1 electromagnetic reversing valve as a whole.

After technician maintenance, the pump truck has no such fault. Karachi praised our technical staff for their serious responsibility, indicating that our cooperation will become more and more intimate.

Huaxing’s products adhere to the principle of high quality, sincere service to customers, achieve the customers' requirements, and acquire the preference of international customers.