What is slewing bearing?

Slewing bearing is a medium and large slewing bearing structure which can bear large loads such as axial load, radial load and overturning moment at the same time. It is widely used in hoisting and transportation machinery, metallurgical machinery, mining machinery, construction machinery, port machinery and automatic assembly line and other medium and large rotary devices. This article mainly introduces what is slewing bearing. 

• The following knowledge points are listed below:

• Basic introduction to slewing bearing

• The basic composition of slewing bearing

• Slewing bearing material

• Code composition of the slewing bearing

1.Basic introduction to slewing bearing

Slewing bearing is a kind of large slewing bearing which can bear the comprehensive loads of large axial load, radial load and overturning moment at the same time.  It is a special structure that integrates support, rotation, transmission and fixation. In general, slewing bearing itself is equipped with mounting holes, lubricating oil and sealing devices, which can meet the different needs of all kinds of main engines under different working conditions. On the other hand, slewing bearing is characterized by its compact structure, convenient guidance and rotation, simple installation and easy maintenance, etc.  It is widely used in hoisting and transportation machinery, excavators, construction and engineering machinery, port machinery, wind power generation, medical equipment, radar and missile launchers and other large rotary devices. 

2. The basic composition of slewing bearing

Slewing bearing is usually composed of four parts: inner circle, outer circle, rolling body and isolation block. Because the core component USES slewing support, it can bear axial force and radial force at the same time. It has many forms, but its structure and composition are basically the same. From left and right are respectively (upper part) : 

1.Outer ring (toothed or toothless)

2. Sealing belt 

3. Rolling body (ball or roller)

4.The fuel nozzles from left and right are (the following part) :

• Plug 

• Cone pin 

• Inner ring (with or without teeth) 

• Isolation block or cage 

• Mounting hole (silk hole or light hole). 

 3. Slewing bearing material

In general, slewing bearing ring is 50Mn, but sometimes 42CrMo is used to meet the needs of the host in special applications. The scroll body is usually GCr15SiMn. There are different types of retainer, such as integral type, sectional type and isolation block type. Integral or sectional retentions are made of 20# steel or ZL102 cast aluminum alloy. The isolation 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, fluorinated rubber, oil - resistant butadiene rubber. 

The common structural forms of slewing bearing include single-row and double-row four-point contact ball bearing, double-row angular contact thrust ball bearing, cross-cylindrical roller and cross-cone roller slewing bearing, three-row cylindrical roller slewing bearing, and ball-column mixed slewing bearing. The above types of slewing bearing are divided into toothless, outer toothed and inner toothed structures according to the bearing and the distribution of gear. 

4. Code composition of the slewing bearing

The representation of slewing bearing, the composition of the bearing, the slewing bearing is composed of the fundamental and the postscript. 

The basic symbol of slewing bearing is divided into three parts: the former is the structural type and the transmission type; the middle is the diameter of rolling body (slewing bearing is the maximum diameter of rolling body for rolling body above two rows); and the rear is the diameter of the center circle of rolling body weight (slewing bearing is the maximum diameter of the center circle for rolling body above two rows). 

(1)  The construction type code shall follow the rules in table 1. 

01 four-point contact ball slewing bearing;02 pairs of ball slewing bearing;11.  Interspersed cylindrical roller slewing bearing;13.  Three rows of cylindrical rollers bearing slewing. 

(2)  The driving type code shall follow the rules in table 2. 

0 toothless type;1.  Small modulus of outer teeth of involute cylindrical gear;2.  The external teeth of involute cylindrical gear have larger modulus;3.  Small modulus of internal teeth of involute cylindrical gear;The internal teeth of involute cylindrical gear are larger modulus. 

(3)  Basic code compilation rules

When the basic code is arranged, the construction type code and the transmission type code are written together, and the front, middle and rear are separated by ".  ". 

I hope the introduction of slewing bearing in this paper will be helpful to you.  Our company specializes in producing all types of slewing bearing.  If you need slewing bearing, please contact us.