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Crane reducer leakage reasons and management tips

27 Mar, 2017

Crane reducer leakage reasons and management tips. There are many reasons cause crane reducer leakage. Check on the reasons on crane reducer and how to manage crane reducer leakage.8iyHenan Dongqi Machinery Co., Ltd

Crane reducer8iyHenan Dongqi Machinery Co., Ltd

Crane reducer Leakage Reasons

1. Pressure difference inside and outside Crane reducer

During Crane reducer operation, movement friction produce heat and affected by the ambient temperature, which makes Crane reducer temperature rise, if no air holes or holes clogged, then pressure inside the machine gradually increased, the higher the internal temperature and the greater the pressure difference with outside, lubricating oil leakage from the gap under the action of pressure difference.8iyHenan Dongqi Machinery Co., Ltd

2. Unreasonable design of Crane reducer

  • 1) Manhole cover is too thin, easy to deformation after tightening bolts, so that combined surface is uneven, the oil leakage from the contact gap;
  • 2) During gear manufacturing process, the casting part is not for annealing or aging treatment, internal stress is not eliminate, inevitable deformation occurs, resulting in gap and leakage;
  • 3) There is no oil-returning slot, lubricating oil accumulated in the seal, cover, combined surface, etc., under the pressure differential, oil leak out from the gap;
  • 4) Seal design is unreasonable. Early Crane reducer usually use oil groove, and felt ring type seal structure, so that when assembly felt is deformed by compressed, and sealed the combined surface cracks. If the shaft neck contact with the seal is not very satisfactory, due to compensation for the performance of blankets is very poor, the seal will lapse in short time. Although there has fuel return hole on the oil groove, bit is easy to be clogged, oil return effect is difficult to play.

3. Excessive amount of fuel

During Crane reducer operation, the oil tank is stirring up badly, lubricating oil splashing around in the machine, if excessive amount of fuel, lubricating oil accumulate large numbers in seals and the joint surface, etc., resulting in leakage.8iyHenan Dongqi Machinery Co., Ltd

4. Improper maintenance process

When equipment maintenance, due to the dirt removal of joint surface is not complete, or improper selection sealant, seals installed backwards direction, replacement of seals not timely, etc. can also cause oil leakage.8iyHenan Dongqi Machinery Co., Ltd

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How to Manage Crane reducer Oil Leakage

Crane reducer8iyHenan Dongqi Machinery Co., Ltd
1. Improved the ventilation cap and inspection hole cover:

Crane reducer internal pressure is greater than the atmospheric pressure is one of the main causes of leakage, if trying to make inner and outside of the machine pressure equalization, oil leakage can be prevented. Although Crane reducer has breathable cap, but the holes are too small, easy to be jammed by pulverized coal and oil fouling. And each time refueling must open the inspection hole cover, turn once to increase the likelihood of leakage, so that makes the originally not leak place leakage. Therefore, we make oil cup type breathable cap, and make the original thin check panel to 6 mm thick, the oil cup breathable cap welded on the cover, holes diameter 6mm, to facilitate ventilation, to achieve pressure equalizing, and when fuel oil through the oil cup, do not need to open the inspection hole cover, which reduce the chance of oil leakage.8iyHenan Dongqi Machinery Co., Ltd

2. Smooth flow:

To make the excess oil that be thrown on the gear bearing not accumulate in the seal, we have to make the extra lubricating oil flow back to the oil pool along a certain direction, which achieves smooth flow. Specific approach is at the lower center of the bearing tile to open a fuel return tank tilted inside the machine, while also open a gap in the end cover, the gap is on the back to the tank, so the excess oil through the gap and oil return tank back to the oil pool.8iyHenan Dongqi Machinery Co., Ltd

3. Using new sealing material:

For Crane reducer static sealing point leakage, new polymer can be used to repair leaking material clogging. If the gear static seal point leak oil during Crane reducer operation, emergency oil stick Putty - 25551 and 90T polymer composite restorative materials of surface engineering technology is available to block, so as to achieve the purpose of eliminating oil leak.8iyHenan Dongqi Machinery Co., Ltd

4. Improve seal structure

  • 1) Output shaft for half shaft Crane reducer seal improvements: Belt-type conveyer, spiral unloading machine, impeller coal feeder and other equipment Crane reducer with half shaft, which is convenient to make modification. To make disintegration of the Crane reducer, remove the coupling, remove the gear shaft seal cover, according to the supporting skeleton oil seal size, outside of the original end cover lathed tank mounted skeleton oil seal, with the spring side inward. When loaded back, if end cap away from the inside of the coupling end 35mm or more, you can install spare oil seal on the shaft outside the end cover, once the oil seals fail, you can remove the damaged seal, and push the secondary oil seal into the end cap, thereby save the disintegration of Crane reducer, removal of couplings and other time consuming processes.
  • 2) Output shaft for the entire shaft Crane reducer seal improvements: the whole shaft drive gear output shaft without couplings, according to 3.1 program improvement, the heavy workload is not realistic. To reduce the workload, simplify the installation process, there designed split end cover, and attempt the open type oil seal. Lathed tank outside the spilt end cover, remove the spring before loaded oil seal, amputate the oil seal to opening shaped, set the oil seal on the shaft from the opening, the opening butted with adhesives, with the opening side up, and then loaded spring, pushed end cap into it.

5. Earnestly implementing repair technology

During Crane reducer repair, the technological procedure should be earnestly implemented, oil seal cannot be installed backwards, not to damage oil seal lip, no deformation of the outer edge, the spring cannot come off, the combined surface to be cleaned, sealants applied evenly, and the amount of fuel cannot exceed the oil gauge scale.8iyHenan Dongqi Machinery Co., Ltd

6. Wiping

Through managing of the Crane reducer static sealing point, it is usually can achieve no leakage, but due to seals aging, poor quality, improper assembly, higher roughness of the shaft surface and related reasons that makes some dynamic seal points still with small leakage, due to poor working environment, coal dust stick to the shaft, it appears greasy and oily, so you need to wipe grease from the shaft after stop running the device.8iyHenan Dongqi Machinery Co., Ltd

If you need crane reducer or types of cranes, please feel free to contact us8iyHenan Dongqi Machinery Co., Ltd

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