concrete pipeline blockage

When the delivery pressure was gradually increased, while the hopper material level does not drop, Concrete block machine, the pump vibration occurs, the pipeline is accompanied by intense vibration and displacement, can be determined a pipe plug.
Blocking parts of the judgment: concrete mixing machine occurs in the pipe, cone, and the vibration of the lot. At this point, the available Hammers beat along the pipeline, sounds boring office blockages; sound crisp office as normal. With the ears, there is rustling as normal, with shrill sound of blockages.