Concrete pump pumping main points

Source: Author: Date: 2013-08-20 Views: 192 Comments: 0 Favorite Print

Abstract: Concrete pump

  (1) concrete pumpability. Concrete pump pumping requirements can be satisfied, when necessary, to determine the mix of pumping concrete pumping through trial.

    ① maximum ratio of coarse aggregate size and caliber of delivery should be: When pumping height 50m or less, not more than one for gravel: 3, for not more than a pebble: 2.5; pumping height at 50 ~ 100m time , should be 1: 3 to 1: 4 range; pumping height of 100m above, should be 1: 4 to 1: 5 between. Flakiness particle content of not more than 10%.

    ② different pumping height, the pump may slump concrete (Table) selection.

     Pumping height (m) 30 or less than 30 ~ 60 60 ~ 100 100

     Slump (m) 100 ~ 140 140 ~ 160 160 ~ 180 180 ~ 200

    ③ suitable for pumping concrete water-cement ratio (0.4 to 0.6): 1.

    ④ sand pumping concrete should rate was 38% to 45%. Fine aggregate should be adopted in the sand, the amount of sand sieve through 0.315m not less than 15%.

    ⑤ Pumpcrete minimum cement content of 300kg / m³.

(2) concrete pump should start pumping after an appropriate amount of water to wet the concrete pump hopper, concrete cylinder and the feed pipe in direct contact with the concrete site. Pumping water and then using one of these methods lubricate these parts: pumping grout; pumping 1: 2 cement mortar; pumping in addition to other components outside the coarse aggregate ratio of cement mortar.

    Lubricated with grout or cement mortar should be decentralized fabric, not concentrated in the same place pouring.

(3) at the start of pumping, concrete pumps should be in a slow, constant speed running state, and then gradually accelerate. And should observe the work pressure of concrete pumps and systems, and the systems to be able to work behind the normal speed pumping.

(4) work as continuous pumping concrete, concrete cylinder piston stroke should be kept to a maximum run to maximize the performance of concrete pumps and concrete cylinders can wear the uniform in the longitudinal direction.

(5) If there is high pressure concrete pump and unstable temperature rise. When vibration and pumping duct obvious difficulties phenomenon, can not be forcibly pumping, should be excluded immediately identify the cause. Can be obtained with a mallet percussion duct elbow. Conical tubes and other parts, and slow or reverse pumping pumps to prevent clogging.

(6) When a blockage occurs, it should take the following measures:

    ① repeated anti-pump and pump are running, gradually returned to suck out the concrete hopper, by mixing and re-pumped.

    ② with a mallet percussion and other methods to identify the blockage site of repeated anti-pump and pump run until after being hit loose concrete to eliminate clogging.

    ③ When the above two methods are ineffective, should be disassembled after the concrete relief blockage site, re-pumping to be discharged after the blockage.

(7) should be used to pump concrete ready-mix concrete, can also be set up at the scene stirred Station Supply pumping concrete, but not pumping hand mixing concrete. Concrete supply should be strictly controlled, and pay attention to changes in the slump, do not meet the requirements of the concrete pumping is not allowed into the pump, in order to ensure the effective work of the concrete pump.

(8) should be set on a concrete pump hopper screen, and let someone feed monitoring to avoid excessive aggregate diameter or foreign objects entering and causing blockage.

(9) When pumping, the stock of the concrete inside the hopper can not be lower than the position of the agitator shaft to prevent air from entering the pump tube caused by pipeline vibration.

(10) when the concrete pumping process requires terminal interrupt time should not exceed 1h. And should be every 5 ~ 10min anti pumps and pump operation are to prevent the pipeline due to bleeding or concrete slump loss is too large and blocked tubes.

(11) After pumping is completed, must be carefully cleaned hopper and pipeline systems. Residual concrete concrete cylinder if removal is not clean, will solidify on the cylinder wall when the piston is running again, the piston sealing surface will have a direct impact on the cylinder wall to withstand the concrete has cured them, causing the piston to push the local spalling. This damage is different from the normal wear of the piston seals, sealing surface can not be self-compensated under pressure, resulting in leakage of plasma or suck air, causing pumping weakness, blockage.

(12) when the concrete can be poor or the concrete pump bleeding, segregation and difficult to pump, should immediately mix, research concrete pumps, piping and pumping process, etc., and take appropriate measures to resolve.