How to install the turntable bearing? How to use YRT bearings?

The YRT state bearing is a mechanism that is suitable for axial and radial loads, and also has high tilt stiffness and extremely high accuracy, which is suitable for rotary tables, so the bearing arrangement in chucks and iron cutter heads, as well as in measurements and experiments. At the same time YRT bearings. The requirements for installation are also very strict, so let's discuss how to install the turret bearing and how to use the YRT bearing?

Let's talk about it. <>

The turntable bearing structure consists of a radial shaft ring and a thrust washer, two needle roller cage frame assemblies and a set of radial cylindrical rollers. Therefore, high tilt stiffness and extreme precision are required, and it is also suitable for rotary tables, and the turret bearings are required to be used with the matching equipment parts. At the same time, the torsion torque of the mounting screw should be controlled during installation.

Therefore, its scope of application is also relatively fixed, and it is also very precise. <>

It is necessary to ensure the safety of the bearing during transportation during installation, and at the same time, in order to make the bearing alignment easier, it is necessary to loosen the connecting spiral of the bearing itself before installation, and then install and tighten or take it off. At the same time, in the process of installation and disassembly, the components of the bearing can not be split and interchanged, if there is difficulty in the rotation of the bearing, it is necessary to loosen the bolt of the installation, and tighten it again in accordance with the order of the cross, so as to prevent the problem of bearing deformation. <>

The bearing has a high bearing capacity, so it is especially suitable for the occasion of radial space and can also avoid the destructive edge stress, and the bearing can also remove the stress to support, the outer ring of the roller adopts the design of the arc surface, and the grease space stored with the sealing ring will be larger, if the load of the bearing is too large, it will also lead to the aggravation of this fatigue, in addition, the bearing is installed incorrectly or the bearing bending will produce a serious detachment phenomenon, which is dangerous, so it is necessary to pay special attention.

Generally speaking, this belongs to the platform bearing, if you want to install effectively, you must do a series of inspections before installation, and also remove burrs, but also clean up the lubricated oil holes, bolt holes; For the YRT bearing, if you want to use it effectively, you can go to the 4S store to install it directly, and then change the fat regularly.

Inspection of turntable bearings before installation, deburring, cleaning of surfaces, bolt holes, lubricating oil holes. Ensure that the surface is dry, the table surface is level, and the size of the shaft and seat hole; Flatness and parallelism of the end face;The perpendicularity of the radial and axial planes. The YRT turntable bearing is a slewing motion mechanism that uses the outer ring to rotate and the inner ring to support, and is generally used in precision rotary tables, medical equipment, measuring instruments, IC manufacturing equipment, etc.

Installation. The installation of the bearing should be determined according to the bearing structure, size and the mating nature of the bearing components, and the pressure should be directly added to the end face of the ring that is tightly fitted, and the pressure shall not be transmitted through the rolling elements, and the bearing installation is generally carried out in the following ways:

Press-fit The inner ring of the bearing is tightly matched with the shaft, and the outer ring and the bearing housing hole are loosely fitted, the bearing can be press-mounted on the shaft with a press, and then the shaft is loaded into the bearing housing hole together with the bearing, and when press-fitting on the end face of the inner ring of the bearing, the matching pipe (copper or mild steel) made of soft metal material is paddled, and the inner diameter of the matching pipe should be slightly larger than the diameter of the journal, and the outer diameter diameter should be slightly smaller than the inner ring flange of the bearing, so as not to be pressed on the cage. The outer ring of the bearing is tightly matched with the housing bore, and when the inner ring is loosely matched with the shaft, the bearing can be pressed into the housing bore first, and the outer diameter of the matching pipe should be slightly smaller than the diameter of the housing bore. If the bearing ring is tightly fitted with the shaft and the housing hole, the inner ring and the outer ring should be pressed into the shaft and the housing hole at the same time, and the structure of the matching pipe should be able to press the end face of the inner ring and the outer ring of the bearing at the same time.

Heated fit A mounting method that uses thermal expansion to convert a tight fit into a loose fit by heating the bearing or housing. It is a common and labor-saving installation method. This method is suitable for the installation of the bearing with a large amount of interference, the bearing or the ring of the separable bearing is put into the oil tank to heat 80-100 evenly before hot installation, and then take out the oil and install it on the shaft as soon as possible, in order to prevent the end face of the inner ring and the shoulder of the shaft from fitting tightly after cooling, the bearing can be axial fastening after cooling.

When the outer ring of the bearing is tightly mated to the light metal housing, the hot fitting method of heating the housing is used to avoid abrasion on the mating surface. When heating the bearing with the oil tank, there should be a grid at a certain distance from the bottom of the box, or the bearing should be hung with a hook, and the bearing can not be put on the bottom of the box to prevent impurities from entering the bearing or uneven heating, there must be a thermometer in the oil tank, and the oil temperature should not exceed 100 to prevent the tempering effect from occurring, so that the hardness of the ring is reduced.

The turntable bearing mould surplus YRT (HRT) is composed of a thrust centripetal shaft ring, a thrust washer, two needle roller holding frame assemblies and a set of centripetal cylindrical rollers rolled in the denier state. The seat and ring have evenly spaced screw holes for mounting. These bearings have high axial and radial load capacity.

High tilting stiffness and extreme precision. Suitable for rotary tables, chucks and milling heads, as well as bearing arrangements in measurements and experiments.

The turntable bearing is a kind of bearing that can bear the comprehensive load such as axial load, radial load and overturning moment at the same time, and is a precision bearing with a special structure that integrates the functions of support, rotation, transmission and fixation.

The turntable bearing basically adopts the design method of negative clearance belt preload to ensure the high rigidity and rotation accuracy of the bearing; In general, the inner and outer rings of the turntable bearing itself are equipped with mounting holes, lubricating oil holes and sealing structures, which are suitable for high-precision CNC turntables, CNC index plates, vertical machining centers, vertical grinders, radars, high-precision medical equipment, etc.

Turntable bearings have the characteristics of compact structure, high rotation accuracy, easy installation and maintenance, etc., turntable bearings mainly include YRT turntable bearings, ZKLDF turntable Qingpi bearings and YRTM bidirectional thrust cylindrical roller combination bearings with angle measurement system. These three series of bearings have the same mounting dimensions, with differences in internal structure and similar performance.

(1) Clean the bearing and bearing-related parts.

2) Check the size and finishing of the related parts.

3) Installation. 4) Check the bearing after installation.

5) Supply lubricant.

It is desirable that the bearing package will be unpacked before it is about to be installed. General grease lubrication, no cleaning, direct filling grease. The lubricating oil is lubricated, and it does not need to be cleaned.

However, bearings for instruments or high-speed bearings should be washed with clean oil to remove rust inhibitors applied to the bearings. Bearings with rust inhibitors removed are prone to rust, so they should not be left alone. In addition, bearings that have been sealed with grease can be used without cleaning.

The mounting method of the bearing varies according to the bearing structure, fit and conditions, and in general, because the shaft is mostly rotated, the inner ring needs an interference fit. Cylindrical bore bearings, mostly pressed into by press, or mostly used by hot filling method. In the case of taper holes, it can be installed directly on the taper shaft or with a sleeve.

When installed in the housing, there is generally a lot of clearance fit, and the outer ring has an interference amount, which is usually pressed in with a press, or there is also a cold shrink fit method for installation after cooling. When dry ice is used as a coolant, the moisture in the air will condense on the surface of the bearing. Therefore, proper anti-rust measures are required.

Flat bearings are relatively simple to install.

1. Prepare a simple plane bearing parts, including loose rings, tight rings, and protective frame balls, as shown below.

2. Relaxation ring (this part is close to the stationary part in practical application), as shown in the following figure.

3. Put the balls framed by the protective frame, as shown in the figure below.

4. Tighten the ring, as shown below.

5. A simple plane bearing is installed, as shown in the figure below.

1. Distinguish the tight ring and loose ring of the bearing (judging according to the size of the inner diameter of the bearing, the hole diameter is different;

2. Distinguish the stationary parts of the mechanism (i.e., the parts that do not move, and the main body refers to the assembly);

3. No matter what the situation, the loose ring of the bearing should always lean on the end face of the stationary part.

Common problem: The tension ring and loose ring of the flat bearing are installed in the opposite position, which will make the bearing useless, and the journal will be worn out very quickly.

Solution: Re-switch the loose ring and tight ring to the next position.

1. Use special tools for bearing installation and disassembly.

Advanced mounting tools can avoid bearing damage caused by improper tools and operation during installation. For example, when installing the bearing, the staff has used the copper rod knock-in method, which is easy to cause the uneven axial force of the bearing, causing the cage to deform, the rolling element to be damaged, and the clearance to become larger, and the copper rod in the process of knocking, the copper dust flies into the bearing cage, which is easy to cause bearing failure.

2. Do a good job of checking the bearing before installation.

For old bearings, check the surface of the ball (column) for burrs, scratches, and cracks. Whether the radial clearance and axial clearance of the old bearing are qualified, generally only the radial clearance is measured.

For new bearings, the first thing to check is whether the bearing type is correct. For example, model 6318 deep groove ball bearing, bearing inner diameter of 90mm, its radial clearance range is, and the maximum wear of the bearing can also be found.

3. Check the matching size of the bearing and the rotor shaft.

When assembling the motor, it is also necessary to carefully check the matching size of the bearing and the rotor shaft during bearing installation, and the matching size of the outer ring of the bearing and the end cover hole.

4. Control the amount of oil in the bearing and bearing chamber.

Excessive amount of oil in the bearing and the box will cause the bearing rolling element to slip, causing the rolling body to change from rolling friction to sliding friction, damaging the bearing rolling element, due to the excessive amount of bearing oil, the free space in the bearing box is small, the running temperature of the bearing will rise, the lubricating oil film of the rolling element will become thinner, the lubrication condition is poor, it is easy to cause the bearing abnormal sound, the surface slip, and shorten the life of the bearing.

In the actual working process, for the bearings running at high temperature and high speed, bearings with sealing surfaces should be used as little as possible, the oil storage capacity of the motor oil cap should be increased, and the oil nozzle should be installed to improve the operating life of the motor bearing.

5. Pay attention to ensure that the insulation is intact.

For bearings with insulation design in the outer ring, care should be taken to ensure that the insulation is intact. If the bearing insulation is damaged during installation, the very thin bearing oil film will be broken down by the shaft voltage, and after the oil film is broken down, not only the lubrication conditions of the rolling elements will be bad, but the electric sparks generated at the same time will form electric erosion of the bearing rolling elements, causing the surface of the rolling elements to be not light, and accelerating the wear of the bearings.