Concrete piston plays a key role in the concrete pumping process, and its wear condition will have a significant impact on the quality of concrete pumping in many aspects.
First of all, the decrease in sealing performance is the most direct impact after wear. As the piston wears, the gap between it and the pump cylinder wall increases, and the original tight seal is destroyed. This makes it easy for the concrete slurry to leak to the rear end of the piston during the pumping process, resulting in a loss of pumping pressure. For example, when the pressure loss reaches a certain level, the flow rate of concrete in the delivery pipeline will decrease, and the pipeline may even be blocked, seriously affecting the continuity and efficiency of pumping.
Worn pistons also have a negative impact on the uniformity of the concrete. Due to a loose seal, air may be mixed into the concrete during pumping. These air bubbles will make the internal structure of the concrete uneven, and the strength of the hardened concrete will be unevenly distributed, and local strength may be insufficient. In some projects that require high concrete quality, such as the pier pouring of large bridges, this strength difference may lead to safety hazards.
The slump of concrete also changes due to piston wear. The worn piston cannot push the concrete stably during the movement, which will cause the concrete to be additionally disturbed and squeezed, resulting in a reduction in slump. As the slump decreases, the fluidity of concrete becomes worse, and the friction increases when transported in pipelines, further aggravating the difficulty of pumping. It will also affect the pouring effect of concrete, making it difficult to fill all corners of the formwork, making the surface of the concrete structure uneven. smooth.
In terms of pumping volume, a worn piston will reduce the actual pumping volume. Because the leaking concrete slurry occupies the concrete space that should have been pushed out, and due to unstable pumping pressure and reduced efficiency, the volume of concrete that can be transported per unit time will also be reduced accordingly. For large-scale concrete pouring projects, this will not only extend the construction period, but may also lead to the emergence of construction joints and affect the integrity of the concrete structure.
Furthermore, a worn piston will accelerate the wear of the pump cylinder wall. The concrete slurry flows repeatedly in the gap between the piston and the pump cylinder wall. The hard particles such as sand in it will wear the pump cylinder wall like abrasives, shortening the service life of the pump cylinder and increasing equipment maintenance costs and downtime.
In addition, the irregular surface after the piston is worn may also scratch the pump cylinder wall, making the pump cylinder wall surface rough, further deteriorating the sealing performance and concrete pumping conditions, forming a vicious cycle.
The worn concrete piston has a comprehensive negative impact on the quality of concrete pumping. Therefore, during concrete pumping operations, it is necessary to pay close attention to the wear of the piston and perform timely maintenance or replacement to ensure the efficiency and high quality of concrete pumping work. Finish.
