Key points for preventing and controlling concrete jams
1. Concrete delamination is the main cause of concrete jams, and the main cause of concrete delamination is improper operation.
2. Concrete jams often occur at the 90° elbow between the middle arm and the forearm.
3. Basic operations for preventing and controlling concrete jams
① The process of pumping water and mortar before pumping concrete must be carried out continuously. If it stops halfway, the backflow of water may isolate the mortar.
② The quality of concrete must meet the requirements. Too much or too little water content will cause concrete jams.
③ Pipeline cleaning must be carried out strictly in accordance with the operating procedures. Improper operation can easily damage the cleaning ball and concrete bag, causing concrete isolation and jams.
④ Pipeline cleaning must be thorough, and no sand should be left in the pipe, otherwise it may cause jams when pouring concrete next time.
⑤ During the process of pumping concrete, do not wait for more than 40 minutes (if the concrete isolation prevention device is not installed), otherwise the concrete will be isolated and jammed at the elbow.
Wear of concrete placing boom pipeline
1. Bends
In normal use, the two 90° elbows at the end of the forearm and the two 90° elbows between the middle arm and the forearm are in the worst condition.
2. Straight pipes
In normal use, the straight pipes on the forearm are the most worn, and the straight pipes on the middle arm are the second most worn, but the straight pipes have a longer service life than the bent pipes.
3. Measures to extend the service life of the pipeline
① Install concrete isolation protection devices to reduce abrasion.
② Rotate the bent pipe 180° after a period of time.
③ Ensure the quality of concrete.