Concrete pumping construction, concrete cleaning is an essential pump after an important step, a good cleaning method can clean the pipeline, but also can all the concrete pipe delivery to the pouring site, not only do not waste concrete, And economic and environmental protection. S pipe valve concrete pump commonly used in washing the main three kinds, introduced below.  1 direct water method 1) check the wear between the cutting ring and the eye plate, which is the key to determine the success of direct water cleaning method. If the cutting ring and eye plate wear is not serious, the cutting ring and the eye plate spacing <0.1mm, and no more than 1mm between them trench scratches, available direct water method.  2) After pumping concrete and then pump 0.15 ~ 0.25m \ +3 water-cement ratio of 1: 1.5 or 1: 2 mortar, and then fill the valve in the water, start the pump, the concrete pump To the pouring place, until the delivery pipe outflow of water so far. If the pipeline is shorter, the cleaning effect is better, then the cleaning process ends.  3) When the pipe is longer or cleaning effect is not good, then open the hopper discharge door, open the anti-pump, the hopper and dispensing valve rinse. If the pump is pumped upwards and the height is> 20m, use a wooden hammer to hit the bend at the bottom of the vertical section. If the knocking sound is low, disconnect the elbow and pour out any large aggregates that may accumulate.  4) Close the discharge door, pumping water until the output from the delivery pipe until the water flow. The advantage of direct watering method is that it is not necessary to dismantle the material and cleaning the ball mouth, save time, pumping easier to succeed, especially for the cleaning of shorter pipelines. The shortcomings: ①large amount of water and the pump water must be continuous, water is easily ranked at the pouring site; ② If the vertical upward pipe, usually must be removed elbow; ③ pipe when the pipeline is easy to have residual; ④ pairs Distribution valve sealing more stringent requirements. 2 Remove the material pipe method 1) After pumping the concrete back pump 1 to 2 cycles to eliminate the pressure in the pipe. If you pump up, you must close the shut-off valve to prevent concrete from flowing back and then remove the discharge tube.  2) Open the hopper discharge door, anti-pump distribution valve, concrete tank and hopper in the concrete rinse.  3) The first 6B or 5B delivery pipe mouth out some concrete, stuffed into the soaking ball or cylindrical cleaning piston cleaning.  4) close the distribution valve discharge door, if the cut-off valve is opened, pumping water to the piston pump from the pump output so far.  The advantage of the demolition of the material pipe method is cleaner pipe cleaning, water flow rate can be lower, you can pause. The disadvantage is that the discharge port again after the disassembly difficulties, laborious.  3 plus piston method 1) with 10 to 20 cement bags rolled into a diameter slightly smaller than the diameter of the cylinder, the head slightly pointed, length of about 400mm columnar body, tied with a fine wire, and clean the ball with wire light bar The rear of the columnar, saturated with water.  2) After pumping the concrete back pump 1 to 2 cycles to eliminate the pressure in the pipe, click the button, so that the concrete cylinder piston retreat to the last point. If pumping upwards and shut-off valves must be closed first to prevent backflow of concrete.  3) Remove the discharge tube, open the hopper discharge door, counter-pump distribution valve, concrete tank and hopper in the concrete rinse.  4) Close the hopper discharge door, add water to the hopper, when the water added to the concrete cylinder diameter 2/3 height, the columnar head toward the distribution valve into the concrete cylinder direction, with a length of about 1m, diameter about A 30mm wooden sledge rod will be columnar body, continue to add water to the shaft centerline height.  5) Remove the crowbar, quickly start the pump, add water, until the column from the pump output pump out.  plus piston method has the advantage of cleaning the pipe cleaner, the water flow rate can be lower, you can pause, while reducing the demolition of the mouth and the elbow trouble. The disadvantage is the higher operating requirements, the distribution valve easy to cut the columnar body. The above three kinds of concrete pump washing methods have their own advantages and disadvantages, of which the most reliable is the demolition of material pipe method, the simplest is to add piston method, such as the short distance, the direct water method is a good choice. The specific method should be based on the actual situation of construction, in short, to be both effective and economical.