HG/T 2121-1991 Technical requirements for tilting pad radial sliding bearings
Some standard content:
Chemical Industry Standard of the People's Republic of China
HG/T2121--91
Technical Conditions for Tilt Pad Radial Sliding Bearings
Published on August 19, 1991
Ministry of Chemical Industry of the People's Republic of China
The standard is implemented on January 1, 1992
Chemical Industry Standard of the People's Republic of China
Technical Conditions for Tilt Pad Radial Sliding Bearings
Subject Content and Scope of Application
This standard specifies the requirements for the manufacture, inspection, packaging and storage of tilt pad radial sliding bearings. H-/T2121-
This standard applies to tilt pad radial sliding bearings for centrifugal compressors and steam turbines, and also to tilt pad radial sliding bearings of similar models (hereinafter referred to as bearings)
Reference standards
Technical conditions for high-quality carbon cable structural steel
GB1184 Shape and position tolerances Provisions for unmarked tolerances GB1804
GB6060
Tolerances and fits Limit deviations of dimensions without tolerances Surface roughness comparison specimens
Casting bearing alloy ingots
HG5—1585
CB/Z101
3. Technical requirements
Technical conditions for packaging of chemical machinery parts
CrSnsb11-6 alloy bearing metallographic standards
3.1 Bearings should be manufactured in accordance with the drawings and comply with these technical conditions 3.2 Materials and heat treatment
3.2.1 The base material of the bearing pad is recommended to be 10, 20 or 25 steel. The chemical composition and mechanical properties of the raw materials used should comply with the provisions of GB699 and be forged. Rough and should be normalized. 3.2.2° Bearing alloy is recommended to be bonded to the tile by centrifugal casting. Its chemical composition and hardness should comply with the provisions of GB8740, and the purity of tin used for tin plating should not be lower than the provisions of No. 3 tin in GB728. 3.3 Before pouring the bearing alloy, the oil, rust, etc. on the bonding surface of the tile matrix should be cleaned. 3.4 The metallographic structure of the bearing alloy layer shall be in accordance with Table 1, and the preparation of the metallographic sample and the metallographic structure inspection shall be in accordance with CB/Z-101.: Table
Inspection items
SbSn compound (phase) size
(calculated according to the maximum side length)
8Phase shape and distribution
ePhase shape and distribution
0.015~0.080
(I~4 level)
Bearing alloy thickness
0.015~0.100||t t||(f~5 level)
Square, triangle and other regular geometric shapes are evenly distributed or irregular curves>2.0
0.015~0.150
(1~6 level)
Square, triangle and other regular shapes. Small irregular shapes and slight segregation may appear
Fine grain uneven distribution or granular rod-shaped uniform distribution Ministry of Chemical Industry of the People's Republic of China 1991-08-19 approved standard change full m, ba8o80.ccm granular uneven distribution or slight segregation
1992-01-01 implementation
HG/T2121-91
3.5 The bearing alloy and the matrix should be firmly combined, and the joint surface inspection shall be in accordance with the provisions of Article 4.4 of this standard. 3.6 The surface of the bearing alloy layer shall not have defects such as cracks or loose organization after processing. 3.7 Precision requirements:
3.7.1 The clearance of the center plane of the bearing body in the free state should not be greater than 0.04mm, and the center plane should be 0.12mm in the bearing body.
The position of the cylindrical axisWww.bzxZ.net
3.7.2 The two halves of the bearing body should be accurately aligned and positioned. There should be no looseness or misalignment after reassembly. 3.7.3 The coaxiality of the axis of the outer cylindrical surface of the bearing positioning to the axis of the inner cylindrical surface of the bearing body and the tile shall not be lower than the 6th level specified in Appendix A of GB1184
3.7.4 The verticality of the axial positioning end face of the bearing body to the outer cylindrical axis shall not be lower than the 6th level specified in Appendix A of GB1184. 3.7.5. The thickness deviation of each set of tiles should not be greater than 0.0125mm. 3.7.6 After the bearing is assembled, the tile should be able to swing freely in the bearing body. 3.7.7 The limit deviation of the unindicated tolerance size shall be manufactured according to the ±1/2IT14 grade precision in GB1804. 3.8 Surface roughness
3.8.1 The surface roughness Ra value of the outer cylindrical surface and the end face of the bearing body shall not be higher than 3.2μm. The surface roughness Ra value of the inner cylindrical surface of the bearing body and the tile shall not be higher than 3.2μm. 3.8.28
The surface roughness Ra value of the tile alloy layer after fine machining shall not be higher than .1.6um. Scraping or sanding is not allowed. 3.8.3
3.8.4 The surface roughness Ra value of the back arc surface of the tile shall not be higher than 1.6μm. 3.9 All bearing parts must be inspected and qualified before assembly, and purchased parts should have a certificate of conformity. Inspection methods and rules
4.1 Geometric dimensions and accuracy should be tested within the range of 10~35℃, and the temperature during the test should be recorded in the certificate of conformity. 4.2 Surface roughness inspection should be carried out in accordance with the surface roughness sample block of GB6060 for macroscopic comparison inspection. 4.3 After rough machining of the bearing alloy layer, 5% and not less than 2 pieces of each batch shall be sampled for metallographic inspection. If unqualified, 100% inspection shall be carried out. Before fine machining (surface roughness Ra value is not higher than 6.3um), the surface structure of each bearing alloy must be visually inspected, and its hard points (B phase) should be evenly and densely distributed (more than 20 points per square centimeter). 4.4 The bonding degree between the bearing alloy and the matrix shall be inspected by ultrasonic flaw detection or color flaw detection. The acceptance criteria for ultrasonic flaw detection shall be as specified in Table 2. For high-speed bearings, it is recommended to accept them as Class A or Class B. The acceptance criteria for color flaw detection are as specified in Table-3, and the inspection methods refer to Appendix A (reference parts) and Appendix B (reference parts) Table 2
Defect level
Note: b
Allowed single defect area
Width of radial bearing, mm.
Allowed total sliding surface defects
Standard replacement net w%.bz8080.ccm Various standard industry materials free download Permissible defects within the edge circumference
But not exceeding
Defect length
Not allowed
HG/T2121-91
Number of defects per 50mm length
Not allowed
Note: The total continuous length of the inspected parts is not allowed to have defects below 50mm. 5 Marking, packaging and storage
5.1 Marking
a. Each bearing should have product number, factory number and other marks; b. All bearings shipped out of the factory should have a product quality certificate. 5.2 Packaging
5.2.1 Inner packaging
No allowable
The adjacent distance between two defects
is not less than 10
5.2.1.1 Clean with kerosene with 5% replacement anti-rust oil. After drying, there should be no traces of rust, oil stains and fingerprints. 5.2.1.2 Apply anti-rust grease on the surface of the bearing body
5.2.1.3 The tiles should be wrapped in plastic bags or anti-rust paper for outer packaging. 5.2.2 Outer packaging
Information. The outer packaging of the bearing can be paper boxes or wooden boxes; b. The specifications and materials of paper boxes or wooden boxes shall be selected in accordance with the provisions of HG5--1585. 5.2.3 Packaging marks
The packaging marks of bearings shall comply with the provisions of HG5-1585. 5.3 Storage
Bearings should be placed in a dry place and should not be stored together with acids, alkalis or other chemicals that can cause bearings to rust or affect the surface quality of bearings. Free of charge
HG/T 2121 --91
Appendix A
Ultrasonic testing method for bonding degree between bearing alloy and matrix (reference)
This appendix refers to IS04386/1 (1982 edition) "Structural inspection of metal composite sliding bearings, ultrasonic non-destructive testing of bonding surfaces with bearing alloy thickness not less than 2mm" A1 Scope of application
This appendix is applicable to the ultrasonic testing method for bonding defects between bearing alloy and tile matrix. This method is applicable to sliding bearings composed of a matrix with good sound transmission performance (such as steel, cast iron) and tin-based and lead-based bearing alloys with a thickness of not less than 2mm. The appendix only describes the pulse echo of sound waves input from the surface of the bearing alloy layer, that is, the sound waves reflected from the bonding surface are used to measure the quality of the bonding.
A2 Symbol
IS——Input signal (i.e. starting wave)
BE—Joint surface echo.
—Bearing body bottom surface echo
Reference echo
A3 Testing equipment
A3.1 Ultrasonic testing equipment
Use a calibrated A-type pulse reflection ultrasonic flaw detector for testing. The instrument is equipped with a standard attenuator expressed in decibels, and can adjust the time base (time axis) range, A3.2 Probe
Usually, a standard probe with a chip diameter of 10~30mm is used. A longitudinal wave probe with a frequency of 2MHz is used here to distinguish the input signal from the bonding surface echo signal. If these two signals are unclear, a probe with a higher frequency or a dual crystal probe should be used.
A3.3 Time base (time axis) range: The time base (time axis) range is adjusted to obtain at least two bonding surface echo signals from a suitable reference block. The combination of the alloy layer and the base material of the reference block is partly good and partly bad. The material and thickness of the reference block should be the same as those of the tested tile. A4 Preparation
A4.1 Preparation of the test piece surface (sliding surface) A4.1.1 Test piece surface conditions
The surface roughness Ra value of the test piece is not higher than 5um. A4.1.2 Cleaning of the test piece surface
After the bearing is processed, the dirt and oil on the surface must be removed with an appropriate detergent. If necessary, the surface can be wiped dry with cleaning paper or cloth. A4.2 Ultrasonic scanning
The inspection of sliding bearings can be carried out by direct contact method and water immersion method using light engine oil as coupling agent. Water immersion method can be used for small curvature tiles.
A5 Inspection Grading
The inspection can be carried out in one of three levels with strict grade by grade. A5.11 grade
Inspect all the sides of tiles and dot inspection on the surface of tiles. A5.22 grade
Indicates the standard micro-network
Download the customer standard industry data for free
HG/T2121—91
In addition to inspecting all the joints on the sides of tiles, all the joint surfaces are inspected. A5.33 level
Use the probe to check all the sides and sliding surfaces of the pad row by row. In order to detect all points, the coverage between rows during positioning should be 20% of the chip diameter.
A6 inspection
A6.1 Inspection using the bearing bottom echo method
If the geometry and pad matrix material permit, the bonding degree can be checked by comparing the bonding surface echo with the bottom surface echo. The optional methods are as follows: A6.1.1 Inspection based on the relative intensity of the bonding surface and bottom surface echoes. As described in Section A3.2, when using the probe, when the bonding surface echo height is not greater than the bottom surface echo height, the bonding surface is good (see Figure AI)
If the bonding surface echo height is greater than the bottom surface echo height, then the bonding between the bearing alloy and the pad matrix is not good. In addition, if there is no bottom surface echo and the bonding surface echo is repeated (at least three repeated echoes), then there is no bonding (see Figure A2). When making an assessment, this result is treated as a defective bonding surface. If there are multiple areas in the bearing alloy, this is equivalent to a defective area. Since the bonding surface cannot be correctly assessed, it is regarded as a defect. IS
nenimalundNan
345678910
Figure A1: Good bonding
123456
Figure A2: Unbonded
In the case of very thick and relatively small tiles, or when using a dual-chip probe, even if the bonding is good, the bottom surface echo will be smaller than the bonding surface echo due to beam divergence or sound wave attenuation. In case of doubt, the height ratio between the echo of a good joint and the echo of a poor joint will be determined with the aid of a reference test block. A6.1.2 Inspection according to the reduction in the height of the bottom echo The inspection equipment is calibrated with a standard steel test block. At least two bottom echoes are obtained on the sliding bearing. The height of the first bottom echo is adjusted to 80% of the screen height, and the horizontal magnification knob is adjusted so that the scale on the display screen can easily show the complete wall thickness of the bearing. The position of the intermediate echo before the first bottom echo, the defect on the joint surface or the pad matrix is displayed, and the severity of the defect is determined by the degree of reduction in the bottom echo height (see Figures A3 and A4). Defects with a bottom echo height not exceeding 50% of the screen height are considered to be major defects.
Standard damage replacement network%%
Free download of various standard industry information
HG/T2121—91
Figure A3 Good bonding
A6.2·Detection when there is no bottom surface echo
Figure A4 Poor bonding
Use a reference echo from a reference test block with a thickness and material similar to that of the tile to evaluate the bonding surface, and the reference echo height is adjusted to 80% of the screen height (see Figures A5 and A7). When the first echo height of the joint surface is less than the reference echo height, the joint surface is good (see Figure A6). When the first echo height returned from the joint surface is equal to the reference echo height, it indicates that there is a defect in the joint surface (see Figure A8).
Adjustment of reference echo
Adjustment of reference echo
Standards for various industries
Poor joint
HG/T2121—91
If a porous area equivalent to a defect appears in the bearing alloy, it is considered a defect because the joint surface cannot be reliably assessed.
A7 Assessment
When the test results are assessed in accordance with this appendix, bearings with joint surface defects equal to or greater than the crystal radius are usually judged to be defective.
A7.1 Marking of defect areas
If possible, the defect areas should be marked with continuous dividing lines. The center position of the probe is the decisive factor in determining the transition boundary between bonding and non-bonding.
Single point defects whose size is equal to the radius of the wafer should be marked. If the distance between two or more defects is less than 10mm, they are considered to be continuous defects. For single defects, the aspect ratio of 1:4 is allowed. A7.2 Permissible defects
See Table A1.
Defect groups
Note: 1) b
Permissible single defects\
Permissible total defects on sliding surfaces"
Permissible defects within the edge circumference"
But not more than mm
-For radial bearings, Table Indicates the width of the bearing, and for thrust bearings, it indicates the width of the sector block or ring, mm; .2) For the bearing pad in the radial bearing, the bearing surface area is (D/2)·b. For the surface area of the pad in the tilting pad thrust bearing and the surface area of the ring in the annular thrust bearing, the oil groove area divided by all the balance surfaces should be deducted; 3) When inspecting the edge area of the bearing, do not be affected by certain defects (referring to those defects that are less than half of the allowable defect length). This appendix indicates the inspection level and defect group according to the following provisions. For example, inspection level 2, defect group C, is expressed as: Inspection HG/T 2121~2C.
A8 Test report
Writing test reports must have a consistent format, and the following contents should be indicated in the test report: a
Sliding bearing size and material;
Thickness of the alloy layer of the tested bearing;
Testing instrument:
Type and size of the probe, output power; test frequency;
Magnification, test area (magnification in dB); reference test block (size and material);
Bearing manufacturer, test date,
If defects are found, the exact location of the defect should be marked on the sliding surface drawing in the test report. 2soo/ccaFree download of various standard industry information HG/T2121-91
Appendix B
Coloring inspection method for the bonding degree of bearing alloy to matrix (reference)
This appendix refers to the quality standard "Coloring inspection method for white alloy" of Ishikawajima-Harima Heavy Industries Turbine Machinery Manufacturing Plant of Japan. B1 The bearing alloy is inspected after rough processing. B2 There is no rust on the inspected surface.
B3 Use a cleaning solution to thoroughly remove dust, oil and other foreign matter on the inspected surface and keep it clean. B4 Use a brush or sprayer to evenly apply the penetrant on the inspected surface. After keeping it for 5 minutes or more, remove it with a cleaning solution.
Apply the developer uniformly on all the inspected surfaces, and inspect 5 minutes or more after the developer is applied. B5
Additional instructions;
This standard is proposed by China National Chemical Equipment Corporation, and is technically managed by the Chemical Machinery Research Institute of the Ministry of Chemical Industry. This standard is drafted by the Chemical Machinery Plant of Nanjing Chemical Industry (Group) Corporation. The main drafter of this standard is Hu Lan.
Standard submission mc.bz60co.com People's Republic of China
Chemical Industry Standard
Technical Conditions for Tilt Pad Radial Sliding Bearings
HG/T212191
Editor Chemical Industry Standard Compilation Department
(Institute of Standardization, Ministry of Chemical Industry)
Postal Code: 100013
Printing Institute of Standardization, Ministry of Chemical Industry
Copyright reserved, no printing allowed
Format 880×12301/16 Number of Printing Sheets 16000 First Edition September 1992 First Printing September 1992 Number of Printings 1300
Standard Exchange Network.baoa.com
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.