How to Lubricate Overhead Crane, Manual or Centralized Lubrication?

The lubrication of an electric travelling crane is an important aspect of its everyday maintenance. The quality of electric travelling crane lubrication has an impact on not only the operation of the crane but also the operating life of its parts and components. What's more, it has an impact on the safety and efficiency of electric crane operations. As a result, crane maintenance staff should inspect the electric travelling crane's lubrication state on a regular basis and refill the oil as needed.

There are numerous points on the overhead crane that require lubrication. Lubrication is required on all contact surfaces of holes and shafts, as well as mechanical friction surfaces. Lubrication can be done in two ways: manually decentralized lubrication or automatically centralized lubrication.

Manual decentralized lubrication

Medium and small electric travelling cranes often require manual decentralized lubrication. Manual lubrication involves refueling the lubrication points separately with a lubricating screw or grease cup. Manual lubrication is simple and inexpensive, but it takes lubrication workers longer to lubricate each and every lubrication point, and the lubrication holes are readily blocked owing to dust exposure. Furthermore, manually lubricating some lubrication locations is dangerous. As a result, a centralized lubricating system is employed.

Centralized lubrication system

The lubrication pump is used in a centralized lubrication system. When lubrication is required, maintenance staff need merely replenish the lubrication pump, and the lubricant can then be pumped to each lubricant point. It is dependable and secure. A monitoring system can also be added to keep track of the lubrication condition of lubricating points. Because the electric travelling crane does not need to be stopped to be lubricated, the centralized lubrication system is widely used on electric travelling cranes used in production lines, such as steel-making production lines, which can greatly improve working efficiency while also providing a pleasant working environment for maintenance workers.

Electric travelling crane lubrication positions

The operation of an overhead electric travelling crane is dependent on proper lubrication; if the lubricating oil fails, the overhead electric travelling crane will begin to wear out. As a result, proper lubrication is critical for the overhead electric travelling crane. Depending on the location, different parts' lubrication should be examined every 2 to 3 months. The lubricating cycle for overhead electric travelling cranes operating in difficult environments should be lowered proportionately.

1. Lubricating position

The gearbox, open gear, wheel bearing, rail, motor bearing, and brake are some of crane components needs to be lubricated.

2. Here we discuss the lubrication position in detail:

Lubrication should be done according to the maintenance manual's specifications, and different types of lubrication oil should not be mixed.

1). Gearbox: lubrication is usually done with an oil pool, with N100 load gear oil or 30 gear oil in the summer and N78 load gear oil or 20 gear oil in the winter. The level of gearbox lubrication oil should be checked frequently using an oil needle or the oil cover; timely supplementation is required, and the lubrication oil should be replaced every half year.

2) Hydraulic brake actuator: use 25 transformer oil in the summer and No. 10 aviation or instrument oil in the winter.
3)Synthetic graphite calcium base grease or other wire rope grease is used to lubricate the wire rope, and the grease is coated on the steel wire rope. Pay close attention to ensure that no oil penetrates the wire rope.
4) Lubricate various portions of the bearing, gear coupling, and open gear with lithium-based grease, 2 in summer, No. 1 in winter.

5) Use calcium or lithium-based grease or 45 oil to lubricate joints and bolts with a minor relative movement.

Maintenance on Gearbox Oil Leaks

When the gearbox is functioning, the internal pressure rises, resulting in oil leakage, which is one of the most common equipment failures. The general treatment approach is:

• A, the maximum capacity of the lubrication oil should not be exceeded.
• B, the deceleration vent shall remain in good working order;
• C, Check out the gearbox, reducer, and static residual sealant on the surface of the seals should be cleaned in equally covered with sealing glue (601 polymer liquid sealant recommended), to be a little glue after polymerization, and fasten the bolts in the box.
• D, Any aging deformation or wear on a dynamic surface seal should be replaced as soon as possible.

Maintenance of hydraulic drive

Single push rod and multiple push points are used in hydraulic drives.

A hydraulic actuator that should be used with operating oil is advised.

When the ambient temperature is above -10 degrees Fahrenheit, DB-25 transformer oil should be used.

When the ambient temperature is -10 degrees or lower, 10 aviation hydraulic oil should be used.

Refueling Procedures 

Unscrew the oil plug, slowly fueling into the working oil to the rated level, tighten the oil plug, pull up and down the push rod many times to expel air from the cylinder, fueling into the oil to the rated level, then tighten the oil plug.

Working oil replacement

Periodic inspection of working oil, timely refueling of oil, and changing suitable oil based on changes in working temperature, notably for open air operating hydraulic brakes, the lubricating oil replacement steps should be as follows: Remove the hydraulic actuator from the brake frame first, then unscrew the oil plug, invert the drive, and drain the original oil before refueling as directed.

The following difficulties should be addressed while using hydraulic oil: If the oil temperature is normal, no water or pollutants are present, notice the bubble; if the bubble is excessive, the cause should be investigated.

Matters needing attention

• 1)If an excessive oil spill occurs, increase the amount of oil or oil needle into the upper and lower limits of calibration, but not higher than the upper limit.
• 2) Lubricating oil should be maintained clean at all times. If you use grease, make sure to clean up any leftover grease.
• 3) Oil pipeline cleaning should be done on a regular basis to keep the oil flowing smoothly.
• 4)Oil from different models and brands must not be mixed.
• 5)Customers can utilize their experience and relevant knowledge on the selection of lubricants more suitable for varied occasions of lubricating oil and grease for the recommended model specifications in point 2 above. The selection of the time should take into account the condition, load, temperature, filth, and other factors. Sodium-based grease should not be used if there is water at the points.

If you have any problem or doubt on overhead electric travelling crane, gantry electric travelling crane, jib electric travelling crane, or electric hoist, winch, please feel free to contact us . Types of electric travelling cranes and related electric travelling crane services including electric travelling crane lubrication are available from us.