There are many advantages for the hanging roller type concrete pipe machine, here will not expound anymore. Recent years, many publications and materials have reflected that the anti-permeability of hanging roller concrete pipe machines is not perfect and needed to be solved. From the quality statistical form of hanging roller pipe of our company, the phenomenons such as bad compactness, honeycomb and ballast-surface has occupied 15.2% of all products, and exposed reinforcing bar is 11.71%. With the analysis, we think:
1. The dry and wet degree of harsh concrete not being controlled well, thickness of roll shaft, revolving speed and not operating according to technical regulations are the reasons resulting to honeycomb and ballast-surface and bad anti-permeability.
2. The reasons why the reinforcing bars are exposed are the different degree of damage of steel reinforcing framework being pressed under roll pressure, the unevenness of materials charging, de-normalization of aggregate size.
The hanging roller pipes relying only on the roll shaft and roll pressure and centrifuge forming will not meet the quality requirements. Even the effective technology improvement will not solve the quality defect of hanging roller pipe drastically.
Above image is the roll shaft vibration of changed hanging roller concrete pipe machine of Φ600～900×2m. The roll shaft is made with seamless steel tube of Φ220mm. The vibration device is assembled in the tube and driven by two level adjustable motor and the revolving direction is same with roll shaft. The roll shaft vibration is happened when the materials are charged. In this way, the harsh concrete can be liquefied to avoid the damage of reinforcing steel framework. Add with the centrifuge and roll pressure, the honeycomb, ballast-surface, and steel exposed can be overcome so that improve the anti-permeability.
The transform of hanging roll with inner vibration is though, complex, the difficulty is not too much. The main shaft structure and choose of bearing are the factors only needed considering. The small-size hanging roll machine should choose roll bearing, and big-size hanging roll machine should use sliding bearing. The latter vibration resistance is better than former's which will improve the service life. In a word, increasing the inner vibration of suspension roller machine is an ideal measurement to improve the quality of suspension roller machine making pipes. When the inner vibration device of roll shaft rotates with roll shaft, the rotational speed won't affect the stress state of main shaft of suspension roll machine, framework of machine and portal frame. Because the vibration device will not generate vibration as the revolving speed cann't reach a certain speed. The inner vibration of roll shaft technology will get more attention and application as well as better economical effect.