china industrial positioners slewing bearing manufacturer

1.The technical difficulties of Luoyang Bearing’s analytical division of large bearings

Split large bearings, generally from 2 meters to 10 meters in diameter, are required for equipment installation, transportation costs, transportation convenience, and design requirements.

Splitting the large bearing, first of all, in terms of structure, integrity, structure, reliability and stability, obviously cannot be compared with the overall large bearing. Therefore, in terms of accuracy, performance and life, the natural and overall large bearings are Bearings are no different.

However, it is reasonable to exist. In terms of design, working conditions, and transportation, the split bearing structure has to be adopted, so the manufacturing difficulty is obviously not behind closed doors, and requires skilled design experience and manufacturing experience to support.

First, the split structure should be reasonable, and the connection method should be firm and reliable.

Second, the structure should be compact, stocky, proportionate, and strong and weak.

The third is to fully consider the allowance, cutting allowance and deformation during the heat treatment process for custom forgings.

The fourth is the physical phenomenon of thermal expansion and contraction during processing, and the thermal insulation state to eliminate stress.

Fifth, the technological process should fully consider the priority order, and minimize the number of rework, nesting and correction of deformation.

The sixth is the relationship between the mutual loan and size, the accuracy error, and the coordination of the installation size.

2.Three row roller bearings

It can best reflect the use power and use value of heavy-duty and large bearings. At present, roadheaders and shield machines are mainly used. Vertical use, the speed is controlled at 3rpm, the impact load reaches 8000T, and the large torque is enough to penetrate various complex geological and rock conditions. , mountain tunnels, drinking water projects, urban subways, municipal pipe network construction, no problem.

In fact, being able to face complex working conditions recklessly has a lot to do with the structure and layout of heavy-duty bearings. First of all, the high-load three-row cylindrical roller combination slewing bearing is the best choice in the main material, rolling element material, cage material and sealing material, and it is customized production considering complex working conditions.

In terms of structure, it is more comprehensive, with high impact, high load, high torque and high reliability. It can be said that heavy-duty three-row roller bearings can dominate the high-impact and high-load conditions of roadheaders and shield machines. come.

Again, in addition to the structural reassembly protection accident, the application of long balls, large balls, integral steel inlaid copper cages, segmented polyamide, PA66, aluminum bronze segmented cages, and composite materials also plays an important role in reliability. important role.

Finally, the heavy-duty three-row roller bearing greatly enhances the reliability in three major aspects. In terms of design, it is absolutely stable. According to the safety factor of 1:5, the normal height of 130mm is enlarged to 130mm on the shield machine bearing. 550mm, the ball is enlarged from 50mm to 80mm, the cage is also a full cost, and it is at all costs to ensure that the large bearing has a large shoulder and a round waist. In this way, its own weight can match the original design of high load capacity and large torque.

Disposal of slewing bearing maintenance and maintenance

1.1 Anti-rust and packaging

The inner and outer surfaces of the slewing bearing are evenly coated with anti-rust and lubricating oil on both sides of the bearing, and the packaging is wrapped with plastic film kraft paper and linen strips. The outer surface of the large-size slewing bearing should also be wrapped with plastic cloth. For small size slewing bearings, use wooden boxes.

1.2 Warehousing

Regardless of whether it is a new bearing or a slewing bearing that is maintained or repaired, the parts need to be individually rust-proof and lubricated. The whole piece needs to be maintained in accordance with the standard of JB/T10471, including the accuracy of the bearing, horizontal placement, dust-proof, and lubrication.

During the stacking period, it is strictly forbidden to tilt, place under heavy pressure, and place in the open air. The principle of storage allowable time is 10 months. The packaging adopts three layers of protection. After adding grease, the appearance is rust-proof. Film, kraft paper, foam padding, plus wrapping tape.

transportation

Keep the bearings as horizontal as possible during transportation, only allow a slight tilt, and avoid large bumps or vibrations. After unpacking, screw the lifting bolt into the lifting hole of the inner ring or outer ring to transport the bearing to the installation position.

1.3 Safekeeping

1.3.1 In the rust-proof period before use (within 12 months after the bearing leaves the factory). Do not open the package. If maintenance is required, the raceway, outer surface and tooth surface of the slewing bearing should be treated with anti-rust treatment.

1.3.2 Lay it horizontally on a dry and flat site.

1.3.3 If the slewing bearing is stored for more than 12 months, it should be re-rusted.

1.3.4 If multiple sets of slewing bearings are stacked together, at least three evenly distributed wooden pads should be placed between each set of slewing bearings along the circumferential direction, and the upper and lower pads should be placed in the same position.

2 Installation of slewing bearing

2.1 Preparation before installation

2.1.1 The connecting surfaces of the supporting parts shall be machined, and then these surfaces shall be free of burrs and debris. In addition to the supporting parts should have sufficient rigidity, the technical requirements of the connecting surface of the supporting parts should meet the requirements of Table 1.

Technical requirements for connecting surfaces of supporting parts Table 1 µm

2.1.2 When the radial load exceeds 10% of the axial load, there should be radial positioning, and the connecting surface that cannot be machined should be flattened by injection molding.

2.1.3 When unpacking the bearing before installation, care should be taken to avoid damage to the seal and prevent dust from entering the inside of the bearing. Within the specified anti-rust period, it is not necessary to disassemble and clean before installation.

2.2 Soft belt position

The quenched soft tape of the slewing bearing ring is marked “S”. When installing, the position of the soft belt should be in the non-loading area or the non-recurrent load area (the filling plug is always located at the soft belt of the ferrule.)

2.3 Ring gear inspection

Before the mounting bolts are not fully tightened, the gear meshing check should be carried out to ensure that the meshing clearance and the accuracy requirements of the gears are met.

2.4 Tightening of mounting bolts

When installing bolts, quenched and tempered flat washers can be used, and spring washers are prohibited.

After locating the slewing bearing radially, tighten the mounting bolts crosswise and check the free rotation of the bearing at the same time.

There should be sufficient pre-tightening force when tightening the bolt, and its pre-tightening force should be 70% of the yield limit of the bolt material.

3 Use and maintenance

3.1 Inspection of mounting bolts and abnormal phenomena

After about 100 hours of operation of the slewing bearing, check the pre-tightening torque of the mounting bolts of the inner ring and the outer ring, and every 500 hours of operation thereafter.

If there are abnormal phenomena such as noise, impact, and sudden increase in power during use, it should be shut down for inspection.

3.2 Lubrication

After the slewing bearing is installed, it should be filled with suitable grease according to the actual use conditions, and the slewing bearing should be filled while the grease is evenly distributed until the new grease begins to squeeze out of the sealing lip. Fill it every 50~100 hours, and the oiling cycle should be shorter in high environment and dusty conditions. New grease must also be added before and after the machine has been stopped for a long time.

3.3 Cleaning and assembly of slewing bearing

In the assembled slewing bearing, the parts between sleeves and between rows and between rows are not interchangeable. When the bearing is disassembled and cleaned, it should be carried out according to the bearing assembly drawing, and the upper and lower half rings should be assembled according to the original drilling position.

The tooth surface should be cleaned of debris every 10 days and coated with grease.

3.4 Selection of Grease

For the lubrication of the slewing bearing, because there are many comprehensive working factors, the user can choose the best grease according to the specific requirements. Recommended greases are shown in the table.

3.5 Maintenance and repair of heavy-duty bearings shall be carried out with reference to the operating conditions of the equipment manufacturer and the technical specifications of the bearing factory.