GB/T 24610 consists of the following 4 parts, under the general title “Rolling Bearings - Measuring Methods for Vibration”:
- Part 1: Fundamentals;
- Part 2: Radial Ball Bearings with Cylindrical Bore and Outside Surface;
- Part 3: Radial Spherical and Tapered Roller Bearings with Cylindrical Bore and Outside Surface;
- Part 4: Radial Cylindrical Roller Bearings with Cylindrical Bore and Outside Surface.
This part is Part 4 of GB/T 24610.
This part is identical to “Rolling Bearings - Measuring Methods for Vibration - Part 4: Radial Cylindrical Roller Bearings with Cylindrical Bore and Outside Surface" (ISO 15242-4:2007).
This part is a translation of ISO 15242-4:2007.
For the purpose of this part, the following editorial changes were made:
- "this document" was changed to "this part";
- The foreword of the international standard was deleted;
The decimal point "," was replaced by ".".
Annexes A and B of this part are normative.
This part was proposed by China Machinery Industry Federation.
This part is under the jurisdiction of the National Technical Committee on Rolling Bearing of Standardization Administration of China (SAC/TC 98).
Drafting organizations of this part: Luoyang Bearing Research Institute, Luoyang Bearing Science & Technology Co., Ltd., Hangzhou Bearing Test & Research Center.
Chief drafting staff of this part: Guo Baoxia, Li Feixue, Ma Suqing, Chen Fanghua.
Introduction
Vibration of rotating rolling bearings is a complex physical phenomenon dependent on the conditions of operation. Measuring the vibration output of an individual bearing under a certain set of conditions does not necessarily characterize the vibration output under a different set of conditions or when the bearing becomes part of a larger assembly. Assessment of the audible sound generated by the mechanical system incorporating the bearing is complicated further by the influence of the interface conditions, the location and orientation of the sensing device, and the acoustical environment in which the system operates. Assessment of airborne noise, which for the purpose of GB/T 24610 (all parts) can be defined as any disagreeable and undesired sound, is further complicated by the subjective nature of the terms “disagreeable” and “undesired”. Structure-borne vibration can be considered the driving mechanism that ultimately results in the generation of airborne noise. Only selected methods for the measurement of the structure-borne vibration of rotating rolling bearings are addressed in GB/T 24610 (all parts).
Vibration of rotating rolling bearings can be assessed by any of a number of means using various types of transducers and test conditions. No simple set of values characterizing vibration of a bearing is adequate for the evaluation of the vibratory performance in all possible applications. Ultimately, a knowledge of the type of bearing, its application and the purpose of the vibration testing (e.g. as a manufacturing process diagnostic or an assessment of the product quality) is required to select the most suitable method for testing. The field of application for standards on bearing vibration is, therefore, not universal. However, certain methods have established a wide enough level of application to be considered as standard methods for the purposes of this part of GB/T24610.
This part of GB/T 24610 serves to define the detailed method for assessing vibration of single-row and double-row radial cylindrical roller bearings with cylindrical bore and outside surface on a test rig.
NATIONAL STANDARD
OF THE PEOPLE’S REPUBLIC OF CHINA
中華人民共和國國家標準
GB/T 24610.4-2009/ISO 15242-4:2007
Rolling Bearings –
Measuring Methods for Vibration –
Part 4: Radial Cylindrical Roller Bearings with Cylindrical Bore and Outside Surface
滾動軸承振動測量方法
第4部分：具有圓柱孔和圓柱外表面的圓柱滾子軸承
1 Scope
This part of GB/T 24610 specifies vibration measuring methods for single-row and double-row cylindrical roller bearings, under established test conditions.
It covers single-row and double-row cylindrical roller bearings with cylindrical bore and outside surface.
2 Normative References
The following documents, through reference in this part of GB/T 24610, constitute provisions of this part. For dated references, subsequent amendments to (excluding correction to), or revisions of, any of these publications are not applicable. However, the parties who enter into an agreement according to this part are encouraged to research whether the latest editions of these documents are applied or not. For undated references, the latest edition of the referenced document applies.
GB/T 1800.2-2009 Geometrical Product Specifications (GPS) - Limits and Fits - Part 2: Tables of Standard Tolerance Grades and Limit Deviations for Holes and Shafts (ISO 286-2: 1988, MOD)
GB/T 2298-1991 Mechanical Vibration and Shock - Terminology (neq ISO 2041:1990)
GB/T 3141-1994 Industrial Liquid Lubricants - ISO Viscosity Classification (eqv ISO 3448:1992)
GB/T 4199-2003 Rolling Bearings - Tolerances - Definitions (ISO 1132-1:2000, MOD)
GB/T 6930-2002 Rolling Bearings - Vocabulary (ISO 5593:1997, IDT)
GB/T 24610. 1-2009 Rolling Bearings - Measuring Methods for Vibration - Part 1: Fundamentals (ISO 15242-1: 2004, IDT)
ISO 554 Standard Atmospheres for Conditioning and/or Testing - Specifications
ISO 558 Conditioning and Testing - Standard Atmospheres - Definitions
ISO 3205 Preferred Test Temperatures
3 Terms and Definitions
For the purposes of this part, the terms and definitions given in GB/T 4199-2003, GB/T 2298-1991, GB/T 6930-2002 and GB/T 24610.1-2009 apply.
4 Measurement Process
4.1 Speed of rotation
The default speed of rotation shall be 30 s-1 (1 800 r/min) for bearings with outside diameter up to 100 mm and 15 s-1 (900 r/min) for outside diameters larger than 100 up to 200 mm. Tolerance of the speed of rotation shall be +1-2 % of the specified nominal value.
Other speeds and tolerances may be used by agreement between the manufacturer and the customer; e.g. it may be necessary to use a higher speed for bearings in the smaller size range [40 s-1 to 60 s-1 (2 400 r/min to 3 600 r/min)] in order to obtain an adequate vibration signal. Conversely, it may be necessary to use a lower speed for bearings in the larger size range [7.5 s-1 to 10 s-1 (450 r/min to 600 r/min)] to avoid possible roller, rib and raceway damage.
4.2 Bearing radial and axial loads
The bearing load shall be in the radial direction with default values as specified in Table 1.
Other radial loads and tolerances may be used by agreement between the manufacturer and the customer; e.g. depending on bearing design and lubricant used, it may be necessary to use a higher load to prevent roller/raceway slip, or a lower load to avoid possible roller, rib and raceway damage.
For bearings capable of taking axial load, an axial load of up to 30 N shall be applied on the outer ring to ensure stable operation.
The method of applying the radial and axial loads is described in 6.3.3.
Note: default values for radial loads are resultant values. Actual values depend on load angle used (see Figure 3).
?
Table 1 - Default Values for Bearing Radial Load
Bearing outside diameter
D/mm Single-row radial cylindrical roller bearings Double-row radial cylindrical roller bearings
Default values for bearing radial load/N
> ≤ min. max. min. max.
30 50 135 165 165 195
50 70 165 195 225 275
70 100 225 275 315 385
100 140 315 385 430 520
140 170 430 520 565 685
170 200 565 685 720 880
5 Measurement and Evaluation Methods
5.1 Physical quantity measured
The default physical quantity to be measured is vibration velocity, νr.m.s. (μm/s), in the radial direction.
5.2 Frequency range
The velocity signal shall be measured in one or more bands with default frequency ranges as specified in Table 2.
Table 2 - Default Frequency Ranges
Speed of rotation
(r/min) Low band (L) a Medium band (M) a High band (H) a
Default frequencies/Hz
min. max. fL fH fL fH fL fH
882 909 50 150 150 900 900 5 000
1 764 1 818 50 300 300 1 800 1 800 10 000
a For rotational speeds other than the nominal 900 r/min or 1 800 r/min, the frequency range should be adjusted in proportion to the speed. For practical reasons, frequencies lower than 50 Hz or higher than 10 000 Hz should not be used, unless agreed upon between the manufacturer and the customer.
Note: other frequency ranges may be considered by agreement between the manufacturer and the customer in those instances where specific ranges have greater importance to successful operation of the bearing.
The use of spectral analysis of the vibration signal is an alternative.
5.3 Peak measurement
Detection of peaks or spikes in the time domain velocity signal, usually due to surface defects and/or contamination in the test bearing, may be considered as a supplementary option by agreement between the manufacturer and the customer. Various evaluation methods exist depending on the bearing type and the application.
5.4 Testing sequence
Single-row and double-row cylindrical roller bearings shall be tested with the radial load applied in a radial direction on the outer ring (perpendicular to the inner ring axis). An axial load may be necessary to ensure stable operation. If the axial load is used, it is applied from one side of the outer ring. For double-row cylindrical roller bearings the test should be repeated, if the design allows, with the axial load on the other side of the outer ring.
For diagnostic purposes, performing multiple measurements with the outer ring in different angular positions relative to the transducer is appropriate.
For acceptance of the bearing, the highest vibration reading for the appropriate frequency band shall be within the limits mutually agreed between the manufacturer and the customer.
For test duration, see GB/T 24610.1 – 2009, 6.5.
6 Conditions for Measurement
6.1 Bearing conditions for measurement
Prelubricated (greased, oiled or solid lubricated) bearings, including sealed and shielded types, shall be tested in the as-delivered condition.
Note: some greases, oils and solid lubricants increase or decrease bearing vibration levels in comparison with the reference conditions in 6.1.2 and 6.1.3.
The following reference condition procedures (6.1.2 and 6.1.3) normally apply for bearings that are not prelubricated. However, they may also be used in cases of dispute regarding the source of unacceptable vibration levels.
6.1.2 Cleanliness of the bearing
Since contamination affects vibration levels, the bearings must be cleaned effectively, taking care not to introduce contamination or other sources of vibration.
Note: some preservatives may meet the lubrication requirements (see 6.1.3) for vibration testing. In this case, it is not necessary to remove the preservative.
6.1.3 Lubrication
Before testing, bearings shall be adequately lubricated with filtered oil (0.8 μm maximum filter), having a nominal viscosity in the range of 10 mm2/s to 100 mm2/s. Additional information is given in GB/T 3141-1994.
The lubrication procedure shall include some running-in to achieve homogeneous distribution of the lubricant within the bearing.
Note: other lubricant viscosities may be agreed upon between the manufacturer and the customer in order to suit the application.
6.2 Conditions of the test environment
The bearings shall be tested at room temperature in an environment that does not influence the bearing vibration. Additional information is given in ISO 554, ISO 558 and ISO 3205.
6.3 Conditions for the test device
6.3.1 Stiffness of the spindle/mandrel arrangement
The spindle (including the mandrel) used to hold and drive the bearing inner ring shall be so designed and constructed that, except for transmittal of rotary motion, it represents essentially a rigid reference system for the inner ring axis. The transmission of vibration between the spindle/mandrel arrangement and the bearing inner ring in the frequency band used shall be negligible by comparison to the velocities measured (in cases of dispute, precise values shall be agreed between the manufacturer and the customer).
6.3.2 Loading mechanism
The loading system used to apply load to the bearing outer ring shall, ideally, be designed and constructed so that it leaves the ring essentially free to vibrate in all radial, axial, angular or flexural modes according to the bearing type.
