slewing bearing material and structure

slewing bearing material and structure 

Applied Materials

Materials for rings and rolling elements

In general, the turntable bearing rolling elements are made of hardened carbon chromium bearing steel. Grades are made of GCr15 or GCr15SiMn steel; turntable bearing rings are made of surface-hardened steel. When the user has no special requirements, 50Mn steel is generally used. Specific use conditions select other brands of surface hardened steel, such as 42CrMo, 5CrMnMo and so on.

Material for cage

The retainer for turntable bearings has structural forms such as integral, segmented, and isolating block types. The integral and segmented cages are made of 20 # steel or ZL102 cast aluminum alloy. The isolation block type is made of polyamide 1010 resin, ZL102 cast aluminum alloy, etc.

Material for sealing ring

The material of the rotary bearing seal ring is made of oil-resistant rubber or nitrile rubber.

The code of the supply status of the ferrule material and the blank is in accordance with the table. "T" in the table indicates that the ferrule blank is supplied in the quenched and tempered state, and "Z" indicates that the ferrule blank is supplied in the normalized state.

The diameter of the center circle of the rolling body is 3150mm, the ball diameter is 75mm, the gear modulus is m = 20mm, the ring material is 50Mn, and the internal toothed four-point contact ball manufactured by the blank material is normalized.

Turntable bearing material

In general, 50Mn is used for turntable bearing rings, but 42CrMo is sometimes used to meet the needs of the host in special applications. The rolling element is generally selected from GCr15SiMn. The types of the retainer include different structural types such as integral type, segmented type, and isolation block type. The integral or segmented retainer is made of 20 # steel or ZL102 cast aluminum alloy. The spacer block retainer is made of polyamide 1010 resin, ZL102 cast aluminum alloy or QA110-3-1.5 aluminum bronze. Sealing ring material: oil resistant rubber, fluorine-containing rubber, oil resistant nitrile rubber.

The structure of turntable bearings is commonly used in single row, double row four-point contact ball turntable bearings, double row angular contact thrust ball turntable bearings, cross cylindrical roller and cross tapered roller turntable bearings, three row cylindrical roller turntable bearings, balls Different structural forms such as column hybrid turntable bearings. The above-mentioned various types of bearings are divided into different types, such as toothless type, external tooth type, and internal tooth type, according to whether they have teeth and gears

Lubrication of  bearings

Most turntable bearings work under heavy load and low speed conditions. Generally, grease-filled lubrication is used to lubricate the bearings to achieve very satisfactory results. Common greases include calcium-based grease and lithium-based lubrication. Grease, aluminum-based grease, and high-temperature grease, etc., users can choose the most suitable grease according to the specific situation.

Sealing of bearings

The seal of the turntable bearing is to prevent the filled grease from leaking on the one hand, and to prevent external dust, impurities and water from entering the bearing and affecting its normal operation. Since the rotary table bearings mostly work under heavy load and low speed, the seal type of the bearing adopts two structures of rubber seal ring and labyrinth seal. The rubber-sealed structure itself is widely used because it has the advantages of simple structure, small footprint, and reliable sealing performance. However, its shortcomings are that the rubber seal lip is easy to age early and loses its sealability at high temperature, so it is at high temperature. Labyrinth seals should be used for turntable bearings working under working conditions.

Three-row combined roller turntable bearing (slewing bearing)

The three-row roller slewing bearing has three seat rings separated from each other on the upper and lower sides, so that the load of each row of rollers can be accurately determined, and it can bear various loads at the same time. It is the carrying capacity of four products. The largest type, with large shaft and radial dimensions, and strong structure, especially suitable for heavy machinery requiring larger diameters, such as bucket wheel excavators, wheeled cranes, marine cranes, ladle swing and large-tonnage truck cranes. on.

Double-row angular contact ball turntable bearings (slewing bearings)

The double volley ball slewing bearing has three races, and the raceway must be specially designed. The double volley ball slewing bearing has relatively large axial and radial dimensions and a sturdy structure, and is particularly suitable for loading and unloading machinery such as tower cranes and truck cranes that require medium or larger diameters.

Single-row crossed roller turntable bearings (slewing bearings)

Single row cross roller slewing bearing, composed of two races, compact structure, light weight, high manufacturing accuracy, small assembly gap, high installation accuracy requirements, rollers are arranged in a 1: 1 cross arrangement, and can support axial Force, large radial force and tipping moment. It is widely used in lifting and transportation, engineering machinery and military products.

Single row four point contact ball turntable bearing (slewing bearing)

The single-row four-point contact ball bearing slewing bearing is composed of two races. It has a compact structure and light weight. The steel ball contacts the arc raceway at four points. It can simultaneously bear axial force, radial force and tipping moment.

production flow chart

Raw material → forging → turning → inspection → heat treatment → grinding → inspection → quenching and tempering → fine grinding → fine grinding → inspection → assembly → packing inspection → packing  → transportation → customer.

Material of turntable slewing bearing: 50Mn, 42CRMO, GCR15SIMN, 9CR18MO.

Turntable slewing bearing accuracy: P0, P6, P5, P4, P2 accuracy from low to high, the price will also be from low to high.