Some standard content:
Machinery Industry Standard of the People's Republic of China
Brake arm disc brake
Subject content and scope of application
JB/T 7020.1--93
This standard specifies the braking Types, basic parameters, dimensions, technical requirements, test methods and inspection rules of arm disc brakes. This standard applies to normally closed brake arm disc brakes (hereinafter referred to as pushers) with electric wave pressure pushers (hereinafter referred to as pushers) as the driving device. Hereinafter referred to as the brake).
2 cited standards
GB699 high-quality carbon structural steel technical conditions
GB700 carbon structural steel
high-quality carbon structural steel hot-rolled thick steel plate and wide steel strip GB711 | |tt | Inspection
GB1972 Disc Spring
GB4942.1 Motor Housing Protection Classification
Steel Surface Rust Level and Rust Removal Level before Painting GB8923
GB9286 Color Paint and Varnish| |tt||Cross-cut test of paint film
GB9439
Gray iron castings
GB11352
GB/T13384
Casted carbon steel parts for general engineering
General technical conditions for mechanical and electrical product packaging
JB/T 6406.1
JB/T 6406.2
JB/T 6406.3
Type of electric pressed block brake , basic parameters and dimensions electro-hydraulic block brake technical conditions
electro-hydraulic block brake pusher
JB/T7019 disc brake brake disc
JB/T7020.2 brake Arm disc brake
: brake block
JB/T 7020. 3
brake arm disc brake brake pad
3 types, basic parameters and Size
3.1 Type
3.1.1 The brake structure type is divided into the following two types according to the characteristics of the brake frame: a. The brake frame uses a pull-rod release structure, which is called type 1, as shown in the figure 1 shown. Its product code is YP13"; b. The brake frame adopts a wedge-type release structure, which is called type 1, as shown in Figure 2, and its product code is YPB. Approved by the Ministry of Machinery Industry of the People's Republic of China on 1993-09-21 111
implemented on 1994-07-01
JB/T 7020.1--93
base; 2 back-off equalization device; 3 Automatic wear compensation device; 4 brake block assembly: 5--brake spring device: 6-brake block assembly positioning device; 7
brake arm; 8
Picture|| tt||Tie rod mechanism; 9-pusher; 10 brake disc 1-base; 2: back distance equalization device; 3-automatic wear compensation device: 4-brake block assembly; 5-brake spring device 6 roller; 7-Pusher: 8—Wedge: 9 Brake arm: 10 Brake disc Figure 2
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3.1.2 Model representation method
3.1.3 Marking example
JB/T 7020.1 --93
00
Rated braking torque, N·m
Rated thrust, N
Brake disc outer diameter, mm
Product code
The brake rack adopts a brake with a pull rod release structure. The outer diameter of the brake disc is 400mm. The rated thrust of the pusher is 800N and the rated braking torque is 1600N·m. It is marked as
Brake YPB1-400-800-1600JB/T7020.193The brake rack adopts a brake with a wedge release structure. The outer diameter of the brake disc is 400mm. The rated thrust of the pusher is 800N and the rated braking torque is 1000N·㎡. It is marked as
Brake YPBI-400-800-1000 JB/T7020.1—933.2 Basic parameters and dimensions
3.2.1 Basic parameters and dimensions of YPBI brake shall comply with the provisions of Figure 1 and Table 1. 3.2.2 Basic parameters and dimensions of YPBI brake shall comply with the provisions of Figure 2 and Table 2. 3.2.3 Basic parameters and dimensions of thruster shall comply with the provisions of JB/T6406.3. 3.2.4 Brake block dimensions shall comply with the provisions of JB/T7020.2. 3.2.5 Brake pad dimensions shall comply with the provisions of JB/T7020.3. 4 Technical requirements
4.1 Working conditions
4.1.1 The power supply of the brake is three-phase AC, the frequency is 50Hz, and the rated current is 380V. The allowable voltage fluctuation is: the upper limit is 10% and the lower limit is 15%.
4.1.2 The working system of the pusher in the brake is divided into S1 (continuous) working system and S3 (intermittent) working system. The load duration rate in S3 working system is 40% and 60%.
4.1.3 The altitude of the brake use site shall not exceed 2000m (when it exceeds 1000m, the ambient temperature shall be converted according to the relevant provisions of GB755).
The suitable ambient temperature for normal use of the brake is -25~+40C. 4.1.4
4.1.5 The average maximum relative humidity of the wettest month in the brake use site shall not exceed 90%. 4.1.6 There shall be no flammable, explosive and corrosive gases in the working environment around the brake. 4.1.7 The brake base is generally installed horizontally. Note: Special requirements can be negotiated by the supply and demand parties. 4.2 Structural requirements
4.2.1 The brake shall be equipped with a back-off distance and torque adjustment device and a brake pad wear automatic compensation device (hereinafter referred to as the compensation device). And there shall be reliable anti-loosening measures.
4.2.2 The brake has a hinge point for relative swing (except the hinge point connected to the pusher). The shaft sleeve shall be set according to the needs of the structure. The mating surface of each hinge point shall be greased before leaving the factory. 4.2.3 The brake pad assembly (the abbreviation of the brake pad and brake pad after assembly) shall have position-adaptability. 4.2.4 The brake shall be equipped with a reliable back-off distance equalization device to ensure that the back-off distances on both sides of the brake are basically equal in the normal release state. No part of the brake shall float on the brake disc. 148
JB/T7020.1--93
4.2.5 When the brake is working at the maximum back-off distance of the brake pad assembly, the working stroke of the pusher shall not exceed 90% of its rated stroke. 4.2.6 The fixing of the brake pad shall comply with the provisions of JB/T7020.2 and JB/T7020.3. 4.2.7 The enclosure protection level of the electrical part of the brake (motor and junction box) shall not be lower than IP44 specified in GB4942.1. 4.3 Performance requirements
4.3.1 The action performance of the brake shall meet the following requirements a. When the brake is adjusted to the maximum back-off distance, the brake spring working force (hereinafter referred to as the spring working force) and 85% rated voltage are operated at the rated braking torque, and the brake shall be able to be released flexibly; when the brake is adjusted to the maximum back-off distance, the brake shall be able to be closed flexibly when operated at the rated operating frequency of the pusher at 50% spring working force and rated voltage.
4.3.2 The braking torque of the brake shall meet the following requirements:, under the conditions of the spring working force and the brake pad temperature within 250℃, the braking torque of the brake shall not be lower than the rated value in Table 1 and Table 2:
b. The brake should allow the braking torque to be adjusted within the range of 0.7~~1 times the rated value. 4.3.3 The friction performance of the brake pad should comply with the relevant provisions of JB/T7020.3, and 4.3.4 The thrust of the pusher should comply with the relevant provisions of JB/T6406.3. 4.4 Materials and heat treatment
The materials used for the brake should have the official mark and certificate of the manufacturer. The manufacturer of the brake should conduct sampling inspection and can only use it after confirming that it is qualified.
4.4.1 Brake spring: For cylindrical helical springs, use 60Si2Mn with mechanical properties not lower than that specified in GB1222; for disc springs, use 50CrVA (or 60Si2MnA) with mechanical properties not lower than that specified in GB1972. 4.4.2 The mechanical properties of each hinge shaft of the brake shall not be lower than that of 45 steel in GB699, and the heat treatment hardness is 33~38HRC. 4.4.3 The mechanical properties of the brake components shall not be lower than Q235-B in GB700. 4.4.4 The material of the brake pad shall comply with the provisions of Article 4.1 of JB/T7020.2. 4.5 Assembly and precision requirements
4.5.1 When the brake is closed under the working force of the spring, the contact area between each brake pad and the working surface of the brake disc shall not be less than 60% of the effective friction area.
4.5.2 The assembly of the brake block and the brake pad shall be firm and reliable, and there shall be no looseness when the brake pad is worn to the minimum thickness allowed. The gap between the back of the brake pad and the brake matching shall not be greater than 0.15mm at any place. 4.5.3 The surface roughness Ra of the matching hole of each hinge shaft pair is 3.2μm, and the surface roughness Ru of the shaft is 1.6μm. The matching tolerance of each hinge pair shall comply with H9/d9 or H9/f9 in GB1801.4.6 Surface quality requirements
4.6.1 The surfaces of the brake lever, spring lever, brake spring, wedge, roller, parts of the compensation device and all fasteners of the brake shall be treated with anti-rust treatment
4.6.2 Before painting, the components of the brake shall be rust-free and shall meet the requirements of Sa2 or St3 level specified in GB89234.6.3 The non-matching surfaces of the components of the brake shall be coated with anti-rust primer, and the total thickness of the dry paint film shall not be less than 75um. The topcoat shall be evenly coated, bright and consistent in color, and shall not have defects such as missing coating, wrinkles, pinholes and severe sagging. When other methods are used for painting, the effect shall not be lower than the above. 4.6.4 The adhesion of the paint film shall meet the level 2 quality requirements specified in GB9286. 4.7 Brake spring
Brake spring shall comply with the relevant provisions of GB1239.4 and (GB1972. 4.8 Pusher
Pusher shall comply with the provisions of JB/T6406.3. 4.9 Brake block
Brake block shall comply with the provisions of JB/T7020.2. 149
4.10 Brake pad
JB/T7020.1-93
Brake pad shall comply with the provisions of JB/T7020.3. 4.11 Brake disc
Brake disc shall comply with J B/T7019 regulations. 5 Test methods
5.1
·General requirements
5.1.1 The measuring tools and test instruments used in the test shall comply with the relevant national metrological verification regulations. 5.1.2 The working conditions of the test shall comply with the provisions of Article 4.1 of this standard. 5.2 Structural inspection
5.2.1 The contact area of ??the brake pad assembly shall be visually inspected by the coloring method. The brake pad assembly shall be attached to the standard brake disc for inspection. It shall comply with the provisions of Article 4.5.1 of this standard.
5.2.2 Visually inspect the brake Check the fixation of the pad and use a feeler gauge to check the gap between the back of the brake pad and the brake block. 5.2.3 Use the measurement method to check the brake's backing distance, torque adjustment device and anti-loosening measures, and operate according to the product manual to verify their effectiveness.
5.2.4 Use the visual method to check the lubrication of the brake and the setting requirements of the sleeve. 5.2.5 The brake block assembly's follow-up, backing distance uniformity and pusher T stroke test are carried out on the test bench. The specific steps and methods are as follows:
a. Install according to the drawing or product manual requirements a. Operate the brake intermittently and adjust the brake to the maximum back-off distance and spring working force state; b. Operate the brake intermittently and adjust the back-off distance equalization device at any time until the compensation device stops compensating. Use a feeler gauge to measure the back-off distance of the middle part of the brake block assembly on the mesh side. Each value should comply with the provisions of Table 1 or Table 2. At the same time, use visual inspection to check the position-following property and back-off distance equalization of the brake block assembly. Repeat the intermittent operation test at least 5 times. . In the maximum back-off distance state, use a general measuring tool to measure the working stroke of the pusher. 5.2.6 The electrical enclosure protection test shall be carried out in accordance with the provisions of GB4942.1. 5.3 Performance test
5.3.1 The brake action performance test is carried out on the test bench. The specific steps and methods are as follows: a. Adjust the brake to the maximum back distance and spring working force, and reduce the pusher voltage to 85 % of the rated value, operate the brake more than 20 times with power on, and visually check its release flexibility. b. Adjust the brake to the maximum retraction distance and 50% of the spring working force. The pusher voltage is the rated value. Apply power to the brake for more than 20 times, and use visual inspection to check its closing flexibility. 5.3.2 The braking torque is measured on the test bench. The brake pad temperature is within 250C. The same sample and the same parameters (rotation speed, moment of inertia, spring working force) are measured more than 5 times. The results of each test are All shall comply with the provisions of Article 4.3.2a of this standard. 5.3.3 The test report for checking the friction performance of the brake pad should comply with the relevant provisions of JB/T7020.3. 5.3.4 The firmness test of the connection between the brake block and the brake pad is carried out on the test bench. After intermittent braking for 5 to 10 minutes under the working force of the spring, the temperature of the brake pad should not exceed 250°C. The pad should be intact and firmly attached to the brake pad. 5.4 Surface coating quality inspection method
5.4.1 The rust removal treatment of each brake component before painting shall be inspected according to the provisions of GB8923. 5.4.2 The surface quality and surface anti-rust treatment after painting shall be inspected by visual inspection. 5.4.3 The paint film adhesion shall be tested according to the provisions of GB9286 and the cross-hatch test shall be carried out. 5.5 The brake spring shall be inspected according to the provisions of GB1239.4, GB1239.5 and GB1972. 5.6 The thruster inspection shall be carried out in accordance with the provisions of JB/T6406.3. 5.7 The brake pad inspection shall be carried out in accordance with the provisions of JB/T7020.2. 8. Brake pad inspection shall be carried out in accordance with the provisions of JB/T7020.3. 5.8
150
JB/T7020..--.93
5.9 Brake disc inspection shall be carried out in accordance with the provisions of JB/T7019. 6 Inspection Rules
6.1 Outgoing) Inspection
6.1.1 Each product shall be inspected by the quality inspection department of the manufacturer in accordance with the provisions of this standard. Only after passing the inspection can it leave the factory, and a product qualification certificate shall be attached. certificate.
6.1.2 The inspection items are as follows:
a.
h.
c.
d.
e.|| tt||f.
Important connection dimensions (h, K, KKsd in Table 1 and Table 2); Surface rust prevention (Article 4.6.1);
Surface after painting Quality (Article 4.6.3, but does not include testing of paint film thickness); Assembly clearance between brake pads and brake pads (Article 4.5.2); Brake lubrication (Article 4.2.2); ||tt ||Action performance (Article 4.3.1).
All inspection items of factory products must be qualified. 6.1.3
6.2 Type inspection
6.2.1 Type inspection shall be carried out when one of the following situations occurs: a.
b.
c.||tt| |d.
e.
When a new product is finalized or an old product is transferred to a factory for trial production and appraisal, or after formal production, the design and process of the brake are significantly changed, which may affect product performance; the product is long-term When production is resumed after being suspended for more than two years; when the product is in normal production, type inspection shall be conducted every two years; when the national quality supervision department proposes type inspection requirements. 6.2.2 Type inspection sampling method
a.
The type inspection sampling method for the two cases a and b in Article 6.2.1 is: among the trial products, each plate is sampled For one specification, 2 units of each specification should be selected. b. The type inspection sampling method for the two situations c and d in Article 6.2.1 is: among independently produced products, in order of disc diameter. One specification is selected from every two disc diameters, at least three specifications are selected from each series, and at least 2 samples are selected from each specification. When the national quality supervision department proposes type inspection requirements, there is no limit to the specifications and quantities to be sampled. 6.2.3 Type inspection items are as follows:
a.
b.
are exempt from inspection.
Check some of the contents stipulated in Chapter 3 of this standard; check all the contents stipulated in Chapter 4 of this standard, but for the requirements of Articles 4.7 to 4.11, if there are any that meet the requirements of Kaiguan Standard Certificate 6.2.4 All inspected products must pass all inspection items. If there are any unqualified items, it is allowed to double-select products of the same batch and specifications for re-inspection. All re-inspected products must be qualified. 7 Logo and Packaging
7.1 Logo
The brake should have a product sign in a conspicuous position and indicate the following: a.
b.
c.||tt| |d.
e.
Product name and model;
Rated braking torque;
Product weight:
Manufacturing date and factory number;| |tt||Manufacture wide name.
7.2 Packaging
151
JB/T 7020. 1- 93
1 All products leaving the factory need to be packaged. The packaging of the product should comply with the relevant provisions of GB/T13384. 7.2.1
Each product must be accompanied by the following random documents: 7.2.2
a.
Product Certificate;|| tt||b. Product instruction manual:
c.
Packing list
8 Transportation and storage
8.1 Transportation
During transportation and loading, inversion, bumping and It is resistant to impact and can prevent rain, snow and water from being invaded, ensuring that the product is not damaged. 8.2
Storage
Brakes should be stored in a clean, ventilated place with a temperature of 10 40°C and protected from rain, snow and water. They should not be left in the sun for 25-
Exposure.
Quality Guarantee Period
9
Provided that the user abides by the rules for product storage and use, within 6 months from the date of use (but shall not exceed 18 months from the date of shipment) Months) The product should be able to work normally, otherwise the manufacturer should repair or replace it for the user free of charge. Additional notes:
This standard is proposed and administered by the Beijing Hoisting and Transport Machinery Research Institute of the Ministry of Machinery Industry. This standard is drafted by Taiyuan Heavy Machinery College. The main drafters of this standard are Tang Feng, Hua Xiaoyang, Song Yanjun, and Wu Jing. 152
Important connection dimensions (h, K, KKsd in Table 1 and Table 2); Surface rust prevention (Article 4.6.1);
Surface quality after painting (Article 4.6. 3, but not including detection of paint film thickness); assembly clearance between brake pads and brake pads (Article 4.5.2); brake lubrication (Article 4.2.2);
action performance ( Article 4.3.1).
All inspection items of factory products must be qualified. 6.1.3
6.2 Type inspection
6.2.1 Type inspection shall be carried out when one of the following situations occurs: a.
b.
c.||tt| |d.
e.
When a new product is finalized or an old product is transferred to a factory for trial production and appraisal, or after formal production, the design and process of the brake are significantly changed, which may affect product performance; the product is long-term When production is resumed after being suspended for more than two years; when the product is in normal production, type inspection shall be conducted every two years; when the national quality supervision department proposes type inspection requirements. 6.2.2 Type inspection sampling method
a.
The type inspection sampling method for the two cases a and b in Article 6.2.1 is: among the trial products, each plate is sampled For one specification, 2 units of each specification should be selected. b. The type inspection sampling method for the two situations c and d in Article 6.2.1 is: among independently produced products, in order of disc diameter. One specification is selected from every two disc diameters, at least three specifications are selected from each series, and at least 2 samples are selected for each specification. When the national quality supervision department proposes type inspection requirements, there is no limit to the specifications and quantities to be sampled. 6.2.3 Type inspection items are as follows:
a.
b.
are exempt from inspection.
Check some of the contents stipulated in Chapter 3 of this standard; check all the contents stipulated in Chapter 4 of this standard, but for the requirements of Articles 4.7 to 4.11, if there are any that meet the requirements of Kaiguan Standard Certificate 6.2.4 All inspected products must pass all inspection items. If there are any unqualified items, it is allowed to double-select products of the same batch and specifications for re-inspection. All re-inspected products must be qualified. 7 Logo and Packaging
7.1 Logo
The brake should have a product sign in a conspicuous position and indicate the following: a.
b.
c.||tt| |d.
e.
Product name and model;
Rated braking torque;
Product weight:
Manufacturing date and factory number;| |tt||Manufacture wide name.
7.2 Packaging
151
JB/T 7020. 1- 93
1 All products leaving the factory need to be packaged. The packaging of the product should comply with the relevant provisions of GB/T13384. 7.2.1
Each product must be accompanied by the following random documents: 7.2.2
a.
Product Certificate;|| tt||b. Product instruction manual:
c.
Packing list
8 Transportation and storage
8.1 Transportation
During transportation and loading, inversion, bumping and It is resistant to impact and can prevent rain, snow and water from being invaded, ensuring that the product is not damaged. 8.2
Storage
Brakes should be stored in a clean, ventilated place with a temperature of 10 40°C and protected from rain, snow and water. They should not be left in the sun for 25-
Exposure.
Quality Guarantee Period
9
Provided that the user abides by the rules for product storage and use, within 6 months from the date of use (but shall not exceed 18 months from the date of shipment) Months) The product should be able to work normally, otherwise the manufacturer should repair or replace it for the user free of charge. Additional notes:
This standard is proposed and administered by the Beijing Hoisting and Transport Machinery Research Institute of the Ministry of Machinery Industry. This standard is drafted by Taiyuan Heavy Machinery College. The main drafters of this standard are Tang Feng, Hua Xiaoyang, Song Yanjun, and Wu Jing. 152
Important connection dimensions (h, K, KKsd in Table 1 and Table 2); Surface rust prevention (Article 4.6.1);
Surface quality after painting (Article 4.6. 3, but not including detection of paint film thickness); assembly clearance between brake pads and brake pads (Article 4.5.2); brake lubrication (Article 4.2.2);
action performance ( Article 4.3.1).
All inspection items of factory products must be qualified. 6.1.3
6.2 Type inspection
6.2.1 Type inspection shall be carried out when one of the following situations occurs: a.
b.
c.||tt| |d.
e.
When a new product is finalized or an old product is transferred to a factory for trial production and appraisal, or after formal production, the design and process of the brake are significantly changed, which may affect product performance; the product is long-term When production is resumed after being suspended for more than two years; when the product is in normal production, type inspection shall be conducted every two years; when the national quality supervision department proposes type inspection requirements. 6.2.2 Type inspection sampling method
a.
The type inspection sampling method for the two cases a and b in Article 6.2.1 is: among the trial products, each plate is sampled For one specification, 2 products should be selected for each specification. b. The type inspection sampling method for the two situations c and d in Article 6.2.1 is: among independently produced products, in order of disk diameter. One specification is selected from every two disc diameters, at least three specifications are selected from each series, and at least 2 samples are selected from each specification. When the national quality supervision department proposes type inspection requirements, there is no limit to the specifications and quantities to be sampled. 6.2.3 Type inspection items are as follows:
a.
b.
are exempt from inspection.
Check some of the contents stipulated in Chapter 3 of this standard; check all the contents stipulated in Chapter 4 of this standard, but for the requirements of Articles 4.7 to 4.11, if there are any that meet the requirements of Kaiguan Standard Certificate 6.2.4 All inspected products must pass all inspection items. If there are any unqualified items, it is allowed to double-select products of the same batch and specifications for re-inspection. All re-inspected products must be qualified. 7 Logo and Packaging
7.1 Logo
The brake should have a product sign in a conspicuous position and indicate the following: a.
b.
c.||tt| |d.
e.
Product name and model;
Rated braking torque;
Product weight:
Manufacturing date and factory number;| |tt||Manufacture wide name.
7.2 Packaging
151
JB/T 7020. 1- 93
1 All products leaving the factory need to be packaged. The packaging of the product should comply with the relevant provisions of GB/T13384. 7.2.1
Each product must be accompanied by the following random documents: 7.2.2
a.
Product Certificate;|| tt||b. Product instruction manual:
c.
Packing list
8 Transportation and storage
8.1 Transportation
During transportation and loading, inversion, bumping and It is resistant to impact and can prevent rain, snow and water from being invaded, ensuring that the product is not damaged. 8.2
Storage
Brakes should be stored in a clean, ventilated place with a temperature of 10 40°C and protected from rain, snow and water. They should not be left in the sun for 25-
Exposure.
Quality Guarantee Period
9
Provided that the user abides by the rules for product storage and use, within 6 months from the date of use (but shall not exceed 18 months from the date of shipment) Months) The product should be able to work normally, otherwise the manufacturer should repair or replace it for the user free of charge. Additional notes:
This standard is proposed and administered by the Beijing Hoisting and Transport Machinery Research Institute of the Ministry of Machinery Industry. This standard is drafted by Taiyuan Heavy Machinery College. The main drafters of this standard are Tang Feng, Hua Xiaoyang, Song Yanjun, and Wu Jing. 152
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