Acceptance standards for reduction gearboxes:

1. Appearance inspection;

2. No-load and temperature rise tests;

3 , Bearing clearance test;

4. Measurement test of box vibration;

5. Measurement test of shaft oscillation displacement;

6. Equipment and adjustment Requirements;

7. Routine inspection and maintenance of the reduction gearbox.

1. Appearance inspection

1. After visual inspection, the appearance should be shiny, the paint should be even and closed, whether the end caps, upper and lower covers and other studs are complete; whether there are nameplates and nameplates Whether the content is clear and correct;

2. No gaskets are allowed to be filled between the split surfaces of the box, but sealant or water glass can be applied to ensure sealing;

3. During installation, before tightening the box bolts, a 0.05mm feeler gauge should be used to check the sealing between the joint surface of the box cover and box base;

4. The shaft extension seal should be coated with grease . The sealing equipment of the reducer should be installed in strict accordance with the requirements.

2. No-load and temperature rise experiment

Add enough clean lubricating oil according to the specified oil amount, and conduct a forward and reverse no-load test run at an additional speed. The trial run time should be more than half an hour, and should meet the following requirements:

1. The connecting parts and fasteners must not be loose.

2. There should be no oil leakage or oil seepage at any sealing or joint.

3. The operation of the reducer should be balanced and normal, and there should be no impact, vibration or abnormal noise.

4. The oil pump operates normally and the oil circuit is unobstructed.

After the reducer passes the no-load test run, it should be subjected to a load test run. The load during the test should be slowly loaded at the rated speed in four stages according to the rated load of the reducer: 25, 50, 75, and 100. The operation time of each stage is subject to the stable temperature rise of the lubricating oil, and the oil temperature should not exceed 100°C after 3 hours of continuous operation. If the reduction gearbox itself has a cooling system, the oil temperature should not exceed 90°C.

3. Bearing clearance test

When adjusting the differential bearing clearance, you can use a detection table to measure the axial momentum of the differential. The clearance amount can be referred to the Ministry of Communications in recent years. The issued ministry standard or national standard. If there is no testing condition and no reference data, you can refer to the following methods to adjust the bearing clearance:

First tighten the differential bearing adjustment nut in the opposite direction until the differential bearing cannot rotate. Stop, or add enough washers at the bottom of the thrust surface of the semi-floating rear axle case differential bearing to prevent the differential bearing from rolling to a stop. Then gradually remove the gasket or loosen the nut with 0, 05-0, 08 mm thick gaskets, so that the differential can rotate freely in its position, and it is better to achieve 1-2 turns at a time by hand. However, it must be noted that the bearing clearance after tightening the differential bearing cover or semi-floating rear axle housing shall prevail. If the bearing clearance is adjusted by adjusting the nut, the bearing clearance changes after tightening the differential bearing cover, and the bearing cannot rotate. This is because the bearing outer sleeve is under pressure from the bearing cover.

In addition to serious lack of lubricating oil, deformation of the differential housing, and non-concentricity of the bearing neck, the causes of differential bearing wear are mainly due to improper adjustment of the bearing clearance. When the bearing clearance is adjusted too large, the bearing gap will become larger and larger, causing accelerated wear of the transmission connecting parts. If the bearing clearance is adjusted too small, the friction resistance of the bearing will be large. The bearing seat will be enough to support the bearing cover. That is, the bearing cover will not shrink or deform after the bearing cover bolts are tightened. At the same time, the bearing cover cannot move within the bearing cover. High temperatures are generated during transmission. When the lubrication and heat dissipation conditions are poor, the bearings are ablated. When the lubrication and heat dissipation conditions are acceptable, the surface of the roller rod will also be damaged (commonly known as bearing wear).

In short, adjusting the differential bearing clearance during warranty is the key to extending the service life of the bearing. Therefore, you must be careful when adjusting the bearing clearance and perform maintenance in a timely manner.

IV. Measurement experiment of box oscillation

Measuring the oscillation at the bearing seat can obtain the oscillation intensity value at the measuring point. Since the measured oscillation value is a certain quantity, the experiment The supporting structure should preferably be considered a fixed base structure.

During the experiment, it is necessary to prevent extreme vibration of the supporting structure, at least within the speed range of the experiment. The measured oscillation severity is a function of the dynamic coupling between the rolling parts of the gear equipment and the support box. The coupling is very direct when using rolling bearings. When using sliding bearings, the oscillation of the shaft is more or less suppressed due to the damping effect of the oil film. Sliding bearings are greatly affected by speed, torque, load and lubricating oil. When evaluating the vibration intensity of the bearing seat, it is necessary to consider the influence of these changing factors. (Generally caused by unbalance and eccentricity) may not be violently transmitted to the bearing seat of the gear equipment, but under heavy load conditions, the intensity of these vibration transmissions may be very high. In addition, the high-frequency oscillation caused by gear meshing will also be violently transmitted to the bearing seat and will be distributed in the measured box oscillation signal.

When measuring box oscillation, a speed sensor or accelerometer can be used. The linear range measured by the speed sensor depends on its type, generally 10-2500Hz, when it is lower than the gear tooth meshing frequency of the high-speed gear equipment When using an accelerometer with a measurement range of not less than 10kHz, the instrument must be adjusted during use. Special attention must be paid to eliminating the influence of low-frequency noise when converting the signal into a velocity signal. At the same time, attention must be paid to the equipment of the sensor used. The method should be able to ensure the linear measurement range of the instrument.

5. Measurement experiment of shaft oscillation displacement

It is recommended to use non-touch sensors to measure shaft displacement.

There are many forms of non-touch oscillation sensors, and their measurement working principles are different. The main forms are: capacitive, inductive and eddy current sensors. Because eddy current sensors have the advantages of a wide frequency range, small size, and insensitivity to changes in working environment conditions, they are widely used in the measurement of gear equipment.

Non-touch sensors are generally used to measure the relative motion between the gear shaft and the bearing housing. Place the two probes perpendicularly to each other on a regular measurement surface, and the motion trajectory of the gear shaft can be displayed through the oscilloscope. Most flying touch sensors (mainly eddy current sensors) can be used to determine the position of the shaft in the bearing gap.

Although the frequency response range of eddy current sensors is very wide (0-10kHz), when the frequency exceeds 500Hz, generally only a small amount of shaft oscillation signal can be measured. Therefore, non-touch sensors are not suitable for oscillation evaluation above 500Hz.

When non-touch sensors operate in the low-frequency range, they can be used to determine oscillation influencing factors related to shaft imbalance and mechanical errors, such as gear radial runout, roundness, etc. It can also determine gear effects. The size of the additional load caused by force, torque and misalignment force on the shaft can be used to identify bearing-related problems and possible instability.

When installing a non-touch sensor, ensure that there is no large relative movement between the sensor and the bearing or box. It is best to use a rigid component to insert the sensor into the box, and the sensor can be touched from the outside without opening it. The lid allows calibration and repair of the sensor.

The measurement surface should be concentric with the journal and comply with the regulations of the evaluation grade.

6. Equipment and adjustment requirements

1. Rolling bearing equipment.

When installing rolling bearings, the inner ring of the bearing should be close to the shaft shoulder, and the gap must not pass through a 0.05mm thick feeler gauge.

2. Bearing axial clearance.

For bearings whose clearance cannot be adjusted (such as deep groove ball bearings), the axial clearance is 0.25-0.4mm; for bearings whose clearance can be adjusted, the axial clearance value is. Click to view the axial clearance of tapered roller bearings; the axial clearance of angular touch ball bearings.

3. The tooth side gap of gear (worm gear) meshing.

Feeler gauge or lead pressing method can be used. That is, the lead wire is placed on the tooth groove, and then the gear is rolled to flatten the lead wire. The sum of the thickness of the flattened lead wire measured on the two tooth sides is the size of the tooth side.

4. The tooth surface is mottled. The tooth surface of the cylindrical gear is mottled 2-10-4; the bevel gear tooth surface is mottled 2-11-4; the worm drive is mottled 2-12-4.

7. Daily inspection and maintenance of the reducer

Check the oil level, oil temperature and oil pressure every day to see if they are normal, and check whether there is oil leakage at the output and input ends of the reducer and the joints of the piping system. , check whether the temperature of each bearing is normal, listen to whether the operating sound is normal, etc. If abnormal phenomena are found, they should be eliminated immediately.

1. Check the content every day:

Whether the oil temperature (temperature rise) of the reducer is normal.

Inspect whether the oil pump and cooler are turned on, whether the lubricating oil circuit is smooth, and whether the current and pressure of the roller press are normal.

Check whether the reducer sound is normal and whether there is any abnormal sound.

2. Check the content every week:

Use kerosene or gasoline to clean the filter screen, magnetic rod, and the inner cavity of the filter housing and wipe them clean. Foreign matter cleaned out of the filter needs to be deposited. , save and analyze. When copper shavings appear, they need to be cleaned regularly every two days and observe the changes in the copper shavings. If there is no reduction, the machine should be stopped immediately and unpacked for inspection. This is a sign of abnormal wear of the bearing cage.

After cleaning the reducer filter, the lost lubricating oil should be added. Pay attention to the brand, quality and use of the added lubricating oil.

Check whether the bolts are loose, and tighten them immediately if they are loose.

Check whether there is oil leakage on the input shaft and output shaft of the reducer, and whether there is any abnormal noise or temperature.

Check whether the connecting bolts between the motor and the reducer are tight every month, and check whether the connecting bolts between the reducer and the equipment base are tight every week.

3. Check the content every month:

Tighten the bolts connecting the reducer and the torque plate as well as the bolts of the locking plate. Pay attention to the tightening method and tighten it according to the standard requirements.

Check whether the heat exchange performance of the cooler is normal, whether the water pressure and flow rate have changed, and whether cleaning measures are required.

Check the time of the last oil change and ensure that the oil is changed every 6 months (if deterioration, emulsification, etc. are found, replace it immediately).

4. Check the contents every year:

Shut down the machine for maintenance, remove the dust at the input and output ends of the reducer, clean the breathable cap, and repaint the peeling paint on the exterior.

Replace damaged components and replace wearing and consumable parts according to problems that occur during daily use of the equipment.

Recheck whether the locking plate bolts are tightened and tighten them again with additional torque.

Clean the cooler and circulation system pipeline scale. Note that when disassembling the pipeline, you need to wrap each joint with a clean cloth to prevent dust from entering the reducer.

Every three years, it needs to be returned to the factory to start the machine for overhaul, replace damaged parts such as bearings and oil seals, and repair or replace individual worn parts.