Analysis and preventive measures of 4 types of gear transmission lubrication faults in mechanical equipment

Gear drive is widely used in mechanical equipment. The transmission of motion and power by gears is accomplished by the meshing of gear tooth surfaces. Gear transmission will produce friction and wear, need to add lubricating oil lubrication on the tooth surface, the lubricant will form adsorption film and reaction film on the tooth surface, not only can avoid direct metal contact, reduce friction loss, but also can heat dissipation and rust prevention, protect the gear structure. This article shares gear transmission lubrication failure and preventive measures.

Gear lubrication

1) Gear transmission type

There are many ways to classify gear drives:

According to the relative position of the gear axis, it can be divided into parallel shaft cylindrical gear transmission, intersecting shaft bevel gear transmission and staggered shaft helical gear transmission.

According to the working conditions of the gear can be divided into open gear drive, semi-open gear drive and closed gear drive.

According to the hardness of tooth surface, it can be divided into soft tooth surface gear and hard tooth surface gear.

The instantaneous transmission ratio of the gear transmission is constant and high stability, the transmission structure is stable and reliable, the noise generated is small, the transmission power is large, and the efficiency is high, but in the actual application process, the gear transmission has higher requirements for the environment and lubrication conditions, and is not suitable for the transmission between the two shafts with more dust and a long distance, therefore, the selection should be extra careful.

 

2) Lubrication method of gear drive

The lubrication methods of gear transmission of mechanical equipment mainly include oil immersion lubrication, oil injection lubrication, oil mist lubrication and dry oil injection lubrication.

 

Oil injection lubrication is supplied by the oil pump or the central oil supply station at a certain pressure, and the lubricating oil is sprayed to the meshing surface of the gear teeth by the nozzle. The nozzle should be on the side of the gear teeth slightly out, so as to cool the just-meshed gear teeth in time with lubricating oil, and lubricate the gear teeth at the same time.

 

Oil mist lubrication is mainly used for gears with high transmission accuracy and low transmission power.

Dry oil jet lubrication is a common lubrication method for large gear and open gear, and the lubrication effect is very good.

Oil immersion lubrication is to immerse the teeth of the big gear into the oil pool for oil immersion lubrication, when the gear is driven, the lubricating oil is brought to the meshing tooth surface, and the oil is also thrown to the wall of the box. In a multistage gear drive, oil can be brought to the tooth surface of the gear that is not immersed in the oil pool by means of a tanker.

 

Common lubrication failures

There are many reasons for the failure of mechanical equipment, bearing wear, box cracks, screw cuts, coupling damage, surface corrosion, lubrication failure, etc., are common mechanical equipment failures, and lubrication failure is the most common of these mechanical equipment failures, mainly in the following forms:

1) Poor operation, large power loss.

Mechanical equipment in the working process, the transmission parts often appear stuck, intermittent operation and uneven operation, in this case, the equipment can not normally transfer load, transfer movement and energy loss is particularly large.

2) High vibration, high noise and serious environmental pollution.

After the mechanical equipment is started, sometimes there will be a large vibration phenomenon, in this case, serious pollution of the environment, so that the production site loses a sense of security, affecting production.

3) The temperature is too high, and the thermal deformation is large, causing damage.

Reducer parts work for a period of time, the oil temperature in the box rises sharply, and sometimes smoke, oil leakage phenomenon is serious, in this case, due to the high temperature in the box, some parts will fuse to produce failure, some parts of the thermal deformation, the accuracy will decline, there will be abnormal damage, but also reduce the strength of the material, cause damage.

4) Gear pair and other major parts, if the oil film between the meshing surface breaks, the tooth surface fails.

Gear reducer parts in the working process, all kinds of parts have the possibility of damage, but the highest probability of damage and scrap parts are these gear pairs, turbine pairs, bearings and other key parts of meshing transmission. Under harsh working conditions, they can not form a good oil film between the meshing surfaces or form and soon destroy, so the gear pair, turbine pair, bearing surface will be pitting, gluing, plastic deformation, serious wear, impact fracture fusion welding and other tooth surface failure forms, so that mechanical equipment can not work normally.

 

Cause of lubricating failure

There are many reasons for mechanical equipment failure, which can be the reason of the design of the mechanical equipment itself, the reason of the raw materials of the mechanical equipment, or the reason of the impact of the surrounding environment. However, among these influencing factors, lubrication failure is more likely to occur in mechanical equipment failure.

 

When the mechanical equipment is running, there will be friction between the metal parts, and the friction will produce a lot of heat, too much heat will accelerate the corrosion of the metal parts and reduce the service life of the mechanical equipment, so lubrication is very important for the mechanical equipment.

 

The main causes of mechanical equipment lubrication failure are improper selection of lubricants, unreasonable lubrication methods, cumbersome lubrication devices, staff did not master the main points of lubrication, etc. These factors seriously affect the normal operation of mechanical equipment, bring adverse effects to the enterprise, therefore, we must take effective measures to prevent the occurrence of lubrication failure, to ensure the normal operation of mechanical equipment.

 

Measures to prevent mechanical equipment lubrication failure

In order to prevent the production of mechanical equipment lubrication failure, not only need to have a positive attitude, but also strengthen the overall control and management, to analyze the problem from the whole system, take feasible and effective preventive measures to ensure the normal operation of mechanical equipment. More attention should be paid to critical and vulnerable components. Only in this way can we really improve the mechanical efficiency and enterprise efficiency.

1) At the beginning of the design, according to the characteristics of the mechanical equipment and environmental conditions to determine and select the structure, parameters, lubrication devices, materials and lubricating oil, etc., to ensure or as far as possible to make the transmission parts in the working process has a good lubrication state, for special requirements of mechanical equipment, can be specially designed.

 

2) When the equipment is manufactured, it is necessary to strictly control the selection of raw materials for mechanical equipment, the processing accuracy of mechanical equipment parts, the process plan and assembly, etc., and it is also necessary to consider the formation conditions of dynamic pressure oil film lubrication as much as possible to facilitate the lubrication treatment when the mechanical equipment is running.

 

3) When purchasing machinery and equipment, choose a brand with industry reputation, not in order to save costs, and choose inferior machinery and equipment; When starting the mechanical equipment, it should be strictly implemented in accordance with the relevant specifications, and the working state of the lubrication system should be checked regularly; In the selection of transmission parts, it is necessary to choose according to the own conditions and working environment of the mechanical equipment, and choose the most suitable rather than the best.

 

4) When the equipment is used, it is necessary to observe more, do more early fault diagnosis, troubleshoot the fault in time, strengthen the maintenance of the equipment, reduce the energy loss to the minimum degree, improve the utilization rate of the mechanical equipment to the highest degree, in addition, it is necessary to improve the professional quality and personal ability of the mechanical equipment operator, the operator should have the ability to find and solve the fault in time.

 

Source: Hydraulic Learning