The three return drum dryer relies on large gear rings and small gears to
drive the rotation of the drum body. After running for one or two years, the
wear on the tooth surface intensifies, the meshing clearance increases, and
periodic "clicking" sounds are emitted during operation. In severe cases,
stepped grooves or even teeth may appear on the tooth surface, forcing the
entire dryer to stop. The problem usually lies in three aspects: lubrication
method, installation accuracy of the gear ring, and adjustment of the supporting
wheel.
Inadequate lubrication of the tooth surface is the primary cause of rapid
wear. The meshing surface between the large ring gear and the small gear bears
significant contact stress, and is isolated by oil spraying or applying
lubricating grease to form an oil film. The lubricant grade is incorrect, the
injection position is offset, or the injection cycle is too long. The tooth
surface is in a boundary friction state for a long time, and the wear rate
increases exponentially. It is recommended to use high viscosity extreme
pressure grease, spray oil once per shift, and aim the nozzle at the meshing
surface rather than the tooth tip. Check the coverage of the oil film on the
tooth surface. If the tooth surface is shiny and there are no oil stains, it
indicates that the lubrication has failed.
Eccentricity or excessive radial runout during ring gear installation can
accelerate local wear. The large gear ring is made up of two halves spliced
together. When the bolts are not tightened evenly or the cylinder is deformed,
the radial runout of the gear ring exceeds 2mm. During operation, the contact
between the tooth surfaces fluctuates, and local tooth surfaces bear impact
loads. Measure the radial runout at multiple points along the circumference of
the gear ring with a dial gauge. If it exceeds the limit, readjust the splicing
bolts and locating pins, and if necessary, turn and correct the gear ring. The
parallelism and center distance of the small gear also need to be calibrated,
with a deviation controlled within 0.5mm.
Improper adjustment of the supporting wheel causes axial movement of the
cylinder and changes in the meshing width of the gears. If the cylinder moves
back and forth along the axial direction during operation, the width of the
meshing surface of the large and small gears will fluctuate, the force on the
tooth surface will be uneven, and local wear will intensify. Check the gap
between the gear wheel and the rolling ring, and control the axial displacement
of the cylinder within 1-2mm. Four supporting wheels are synchronously adjusted
to ensure that the axis of the cylinder is parallel to the axis of the gear.
Pay attention to the sound of gear engagement during daily patrol inspection.
In case of periodic abnormal noise, check the lubrication first, then measure
the ring gear runout, and finally adjust the supporting wheel. Encountering
problems during equipment operation, welcome to contact the technical team of
Shandong Heavy Industry for communication: Manager Zhang 13583776655 (same as
WeChat).