Four common faults of double cone rotary vacuum dryer and their
treatment methods:
1 The loading amount exceeds its theoretical amount
Since the loading amount of the double cone rotary vacuum dryer is
related to the bulk density of the material (referring to the mass
of the material per unit volume), in general, the material specific
gravity is calculated as 0.6g/cm3 during design. If it exceeds this
specific gravity, the material is still loaded according to the
original theoretical amount in actual production, which will affect
the drying efficiency of the material; secondly, long-term
operation will reduce the life of the motor, reducer, sprocket
chain, etc., until they cannot be used. In addition, some
manufacturers, in order to pursue production and blindly operate
workers, ignore the filling rate (the ratio of the actual loading
volume to the drying cylinder volume), which leads to continuous
equipment operation and product quality problems of the double cone
rotary vacuum dryer. It is worth mentioning that the filling rate
of the double cone rotary vacuum dryer is usually between 30% and
50%, and cannot exceed 60% at most.
2 "Evacuation" phenomenon
If used improperly, the double cone rotary vacuum dryer may
experience phenomena such as vacuum tube bending, sealing sleeve
damage, filter head deformation and even breakage during the drying
process. This is because the outside air (referred to as venting)
is allowed to enter the tank body to recoil the filter head during
the drying process. At this time, the tank body has reached a high
vacuum degree, which will cause a strong impact of positive and
negative airflows and damage the vacuum system.
It is worth noting that: after the material is dried, the tank body
needs to be emptied. When emptying, the flow rate must be
controlled by the venting valve, that is, first open the valve a
little, and then slowly increase it after the vacuum degree in the
tank gradually decreases.
3 The vacuum degree is not reached or is too high
During the drying process, the double cone rotary vacuum dryer
often has insufficient or too high vacuum degree. This is usually
due to three reasons:
(1) Leakage of mechanical seal at the vacuum end;
(2) Leakage or blockage of vacuum pipeline;
(3) Blockage of filter. This requires inspection during use, and
maintenance, cleaning, etc.
4 Excessive noise and leakage at the inlet/outlet
(1) Excessive noise is caused by loose feet, damaged worm gear
reducer, damaged bearing tube, loose or tight chain, etc. of the
double cone rotary vacuum dryer. Just check regularly and eliminate
the fault in time.
(2) Leakage at the inlet and outlet is normally caused by damaged
sealing strips. Just replace them.
