Concrete Pump Truck Maintenance And Servicing (Part 6)
1.8 Maintenance of concrete pipe
To reduce risks and failures during pumping, correct diameter and thickness of pipes, correct type of couplings and safety lock must be adopted. Periodically check whether couplings are locked and pipes are worn overmuch.
1. To ensure a uniform wear of the concrete pipe, all the pipes must the turned clockwise by 120º and bend pipes by 180º every pumping about 3000m3, as shown side. It is shown as left fig..
2. The concrete pipes must be fitted without stress and with placing boom folded. When the boom is opened, there is stress in the delivery pipes.
3. Check the wear of the concrete pipes every time before pumping. Replace the worn pipes if their thickness is less than the set value. To examine the thickness, listen to the sound by hammering it, of course, the more scientific way is to measure pipe thickness by using thickness measuring equipment.
4. Minimum pipe wall thickness is linearly proportional to pumping pressure as shown below:
X-Minimum pipe thickness
Y-Pumping pressure
A-Curve that the pipe ID is 100mm
B-Curve that the pipe ID is 125mm
C-Curve that the pipe ID is 150mm
According to the right diagram, the pipe thickness must be larger than the relative pumping pressure requirement.
Warning:
1. Never use the pipe with its thickness and diameter different from the original.
2. Select proper pipe when concrete is pumped in high pressure state.
3. Any pipe within 3m from the operator must be replaced immediately if they are heavily worn. Before dismantling and replacing the pipe, the pressure in the pipe must be released first.
1.9 Maintenance of cleaning system
The machine is equipped with a high-pressure cleaning water pump. When engine is idle, the pump speed and water pressure is low; with the increase of engine speed, the water pressure will also be increased. If high-pressure cleaning is needed, the engine should be at the Max. set speed.
Clean water must be used. The impurities in water easily lead to blockage in the water pipe and especially in the connection of water tank, they also influence the service life of water pump. In order to clean dirt, the filter and water tank etc. must be periodically cleaned.
In cold weather, the water in system should be drained completely to prevent freeze of water pump and breakage of other parts.
1.10 Maintenance of electric system
For operation and daily maintenance of electric system, please refer to electric manual. We should pay attention to checking the following items:
1. Check whether the function of all electric components is normal.
2. Make sure that the cables particularly cable ties and pressure cables are well insulated in order to avoid components damaged.
3. Check whether the terminals are connected hard and oxidate.
4. Check whether the electric system is connected well to the earth. Principally, any components must be replaced by those which are the same as the originals. Any fittings for replacing must be inspected regular products with the same grade and standard.
