gb/t 21559.2-2023 English Foreign Language Translated Rolling Bearings Linear Motion Rolling Bearings Part 2: Rated static load.
gb/t 21559.2-2023 English Rolling Bearings - Linear Motion Rolling Bearings - Part 2: Static Load Ratings
gbt 21559.2-2023 English version Foreign language version Translated version.
Instead of GB T 215592-2008
Rolling Bearings Linear Motion Rolling Bearings Part 2: Static load rating.
Preface. This document is in accordance with GB T 11-2020 "Guidelines for Standardization Work Part 1: Structure and Drafting Rules of Standardization Documents".
This document is part 2 of GB T 21559 "Rolling bearings – Rolling bearings for linear motion". GB T 21559 has published the following sections:
Part 1: Dynamic load rating and life rating;
Part 2: Static load rating.
This document replaces GB T 215592-2008 "Rolling bearings – Linear motion rolling bearings – Part 2: Rated static load", with GB T 21559Compared to 2-2008, the main technical changes, except for editorial changes, are as follows:
a) Some of the figures have been changed (see figures 2, 4, 8 and 9, and figures 2, 4, 8 and 9 in the 2008 edition);
b) Changed the formula for calculating k0i in equation (1) (see 5.)1.1. 5. of the 2008 edition1.1)。
This document is equivalent to ISO 14728-2:2017 Rolling bearings – Rolling bearings for linear motion – Part 2: Rated static load.
Please note that some of the contents of this document may relate to patents. The issuer of this document assumes no responsibility for identifying patents.
This document is proposed by the China Machinery Industry Federation.
This document is centralized by the National Technical Committee for Standardization of Rolling Bearings (SAC TC98).
The previous editions of the document that this document replaces are as follows:
It was first published in 2008 as GB T 215592-2008;
This is the first revision.
INTRODUCTION. It is often not practical to test the suitability of the linear motion rolling bearings used for each specific application.
The method specified in GB T 21559 has proven to be an appropriate and convenient alternative to testing. GB T 21559 consists of two parts:
Part 1: Dynamic load rating and life rating; The purpose is to specify the calculation method of the rated dynamic load of the linear motion rolling support, and to make:
The dynamic load is used for life calculation.
Part 2: Static load rating. The purpose is to specify the calculation method of the rated static load of linear motion rolling support, and to use the static load as the calculation of the static load safety factor.
Under medium static load, the rolling elements and raceways of the rolling bearing will be permanently deformed, and the permanent deformation will gradually increase with the increase of the load.
For a bearing under a specific use condition, it is often unrealistic to determine whether the deformation of the bearing is permissible by testing the bearing under the use condition. Therefore, other methods are used to determine the suitability of the selected bearing.
Experience has shown that in most bearing applications, a rolling element diameter of 00001 times the total permanent deformation, without causing damage to the subsequent operation of the bearing. Therefore, the equivalent static load that causes such a deformation is specified as the basic static load rating.
Tests in different countries have shown that a load of this magnitude is equal to the maximum load, and a load equivalent to the following calculated contact stresses is generated at the center of contact between the rolling element and the raceway:
For sleeve type recirculating ball linear bearings, 5300MPa;
For recirculating ball linear guide support, 4200MPa 4600MPa (see 3.)9 and Table 1);
For non-recirculating ball linear support, 4200MPa 4600MPa (see 3.)9 and Table 1);
For linear roller support, 4000MPa.
The formulas and coefficients for calculating the basic static load rating are based on these contact stresses.
Depending on the requirements for running smoothness and friction as well as the geometry of the actual contact surface, the permissible equivalent static load can be less than, equal to, or .
Greater than the basic static load rating. Bearing users who lack experience in these areas should consult with the manufacturer.
Rolling Bearings Linear Motion Rolling Bearings Part 2: Static load rating.
1 Scope. This document specifies the calculation method of the basic rated static load, equivalent static load and static load safety factor of linear motion rolling support.
This document is suitable for linear motion rolling bearings that are commonly used in modern times, high-quality hardened bearing steels, manufactured according to good machining methods, and whose shape of the rolling contact surface is essentially a conventional design.
This document does not apply to designs in which rolling elements run directly on a smooth surface of a mechanical device, unless the surface is in all respects comparable to the raceway of the linear motion rolling support component it replaces.
2 Normative references.
The content of the following documents constitutes an essential provision of this document by means of normative references in the text. Among them, the reference document with a date is noted, and only the version corresponding to the date applies to this document; For undated references, the most recent version of the document (including all change orders) applies to this document.
ISO 76 Rolling Bearings Rolingbearings-Static LoadRatings
Note: GB T 4662-2012 Rolling Bearings Static Load Rating (ISO 76:2006, IDT).
ISO 5593 Rolling Bearings Vocabulary (Rolingbearings-Vocabulary).
Note: GB T 6930-2002 Rolling Bearing Glossary (ISO 5593:1997, IDT).
3 Terms and Definitions.
The following terms and definitions as defined in ISO 76 and ISO 5593 apply to this document.
RecirculatingLinear Ballbearing,Sleeve Type,With or Without Raceway Grooves
The basic cylindrical sleeve with a number of recirculating balls enclosed raceways is designed to realize the linear rolling motion along the hardened cylindrical axis.
Note 1: See Figure 1.
Note 2: The raceways on the sleeve are designed as cylindrical or steel inserts with channels parallel to the axis.
RecirculatingLinearball(orroller) bearing,linearguideway,carriage type
A symmetrical, closed raceway linear ball (or roller) support with a plurality of circulating balls (or rollers) designed to realize a linear rolling motion along a hardened guide rail with corresponding raceways.
Note: See Figure 2.
Fig.2. Slider-type recirculating ball (or roller) linear guide support.
Non-recircuatinglinear ball bearing,linear guideway,deepgroove type
Balls are used as rolling elements, and each ball is supported in a straight line with two contact points.
Note 1: See Figure 3
Note 2: The cross-sectional radius of the channel of the two guide rails is equal and is at 052d -+o.
Non-recirculatinglinear ball bearing,linear guideway,fourpoint-contact type
Balls are used as rolling elements, and each ball has a straight line support with four points of contact, Note 1: See Figure 4.
Note 2: The cross-sectional radius of the four contact points on the two rails is equal and is at 0Between 52d ten.
Fig. 4: Four-point contact type non-recirculating ball linear guide support.
Non-recirculating linear roller bearing,linear guideway,flat typeUse needle roller or cylindrical roller as the linear support of the rolling element.
Note: See Figure 5.
Fig.5. Flat non-recirculating roller linear guide support.
Non-recirculating linear roller bearing, linear guideway, V-angle
The Type rails are linear supports for 90" V-shaped members.
Note 1: See Figure 6.
Note 2: Needle rollers or cylindrical rollers are commonly used as rolling elements.
Fig.6. V-type non-recirculating roller linear guide support.
Non-recirculating linear roller bearing,linear guideway,crossedroller type
Linear support with cylindrical rollers arranged in a cross row.
Note: See Figure 7
Fig.7 Crossed roller type non-recirculating roller linear guide support.
static load safety factor
Represents the ratio of the basic rated static load to the equivalent static load to overcome the safety margin on the rolling elements and raceways that is not allowed to exceed the amount of permanent deformation.
Basicstaticrating of Linear Motionrolling Bearing Generated at the center of contact between the maximum load rolling break and the raceway, the calculated contact stress (G...).Quite a static load. Note: These contact stresses are caused by the rolling elements and raceways to produce approximately 00001 times the total permanent deformation, - 8 -5300 MPa for a set of recirculating ball linear bearings
For the linear support of the recirculating ball guide, see Table 1
For non-recirculating ball linear support, see Table 1:
For linear roller supports, AM = 4000 MPa
static equivalent load
A static load that causes the maximum load at the center of contact between the rolling element and the raceway to produce the same contact stress as the actual load.
direction of load
The direction in which the load is applied when calculating the rated load.
Note: When calculating the basic rated static load, the determination of the load direction of the linear motion rolling support is shown by the arrow in Figure 8.
m) 3.1 in.
b)3.2 in.
c)3.4 in.
d) 3.7 in.
Fig.8. Load direction. 4 and 37).
pitch diameterFor a simple recirculating ball linear bearing, the diameter of the circle that encompasses the center of the ball in contact with the raceway within the cross-section of the vertical bearing axis.
Nominal contact angle
The angle between the load direction of the linear support and the resultant nominal line of action of the resultant force transmitted to the rolling elements through the supported raceway member Note: See Figure 9.
4 symbols. The symbols given in ISO 76, ISO 15241 and Table 2 apply to this document.
5 Basic static load rating.
5.1 Straight ball support.
5.1.1 Recirculating ball linear bearings with or without grooved sleeves.
5.1.2. Slider type recirculating ball linear guide rail support.
5.1.3. Deep groove type and four-point contact type non-recirculating ball linear guide support.
5.2 Linear roller support.
5.2.1. Slider type circulating roller linear guide support.
5.2.2 Flat, V-type and crossed roller type non-recirculating roller linear guide support.
6 Equivalent static load.
The equivalent static load of a linear motion rolling support is given by equation (6):
When the direction of the support load f is the normal direction shown in Figure 8, and the support travels within the standard range, the static load coefficient is &. =1。When these conditions are not met, the manufacturer should be consulted with the applicable & Coefficient value.
7 Static load safety factor.
The static load safety factor of a linear motion rolling support is given by equation (7):
Static load safety factor s. It should be greater than 2 under normal working conditions. Under special working conditions, it is advisable to consult the manufacturer for the applicable s. Coefficient value.