Concrete pump transfer case does not deal with faulty switch

Concrete pump is adapted from the truck chassis , which is mounted on the chassis movement and power transmission , pumping and mixing equipment , fabrics , and other assistive devices devices . Concrete pump power through power transfer case sends power from the engine to the rear axle or group of pumps , pump pushes the piston driven concrete pump . Cloth and then use the lever on the pump delivery tube , the concrete to a certain height and distance. Concrete pump truck driving engine in addition to the driver , but also to drive the pumping mechanism , stirring mechanism and fabric institutions working device .

Concrete pump power of the working device from car engines. When concrete pump work , engine powered vehicles to pass through the transmission transfer case , and then after the transfer case switch is passed to each pump or chassis bridge. When the driver switches to the pumping position to issue instructions , pneumatic solenoid valve control box on the sub- acting cylinder push fork , fork and then push the switch to the pumping gear isolated location , and cut off the power after the bridge to make cars in parking state . Conversely , switch to driving position .

2 Faults and fault analysis

I have a Putzmeister Machinery ( Shanghai ) Company produced BSF36.09 pump , once at the end of the construction site , ready to call it a day when , all of a sudden the whole car without all the pressure of the hydraulic system failure , the feeling of moving the output power of the traveling position of the box , when the driver issues a handover command to the pump position , the rod end can see the retraction of the yoke , but the split gear splitter box is not to leave the driving position , so that the gear is not will switch to pumping position. Although already recovered arms , three legs have been filed , but the leg has not been completely recovered. The most vexing problem is that there is a front leg is fully supported on the ground , pressing above about 1/4 of the body weight , close to the heavy beat of the 10t in the legs . If you do not solve the problem, even if pump can run , can not be opened from the site back to the company .

Treatment 3 pump leg problems

Outrigger pump hydraulic system analysis principles found in each leg pump with two-way brake cylinders are protected even remove the oil pipeline can not be rodless cylinder chamber hydraulic oil release , and two-way system valve connected to the hydraulic cylinder rod chamber inlet , under the two-way brake without removing the case can not open , they justify the legs . Only in the two-way brake Anyway , the truck 's hydraulic system diagram legs shown in Figure 1 .

The legs of the two-way brake ( not detailed in the spare parts of the bi- manual brake structure ) has a large nut , two-way analysis of two controllable brake is composed of a one-way valve , the nut is one , people try to loosen the nut with a wrench , hydraulic oil leaking . When the song to three or four laps , the controllable check valve is ejected , it is fortunate that the operator be prepared to escape the body , causing no injuries. The final leg away with a crowbar , etc. , and it reinforced with wire , also used a similar method to recover the other three legs closed .

Summarize experience in dealing with this failure should jack the legs from the top arm , will release the hydraulic cylinder inside , and then split two-way brake , there will be dangerous.

The method of repair and process transfer case

After the truck stopped , removed before the transfer case , the cis -axis . Hand pulling hoist with a main pump will pump Diaozhu , remove the pump , and then remove the pump arm and leg . Remove the transfer case, after its disintegration , found copper alloy fork broke . Transfer case structure diagram shown in Figure 2 .

And Putzmeister Machinery ( Shanghai ) Company Contact buy fork matters , manufacturers can not provide cash , only ordered to the German headquarters , but after ten days to arrive . To solve the immediate problems , decided to study the use of brazing method to repair a broken fork , first end face grinding machine with broken beat groove with fork weld welding method , and then angle grinder to dispose of excess solder meat , then sandpaper surface treatment such as its good , installed after the cleaning process , testing everything is normal. Has been used for three years is not such a failure occur again.