This standard specifies the technical requirements, test methods, inspection rules and marking, packaging and storage requirements for precession unloading centrifuges (hereinafter referred to as centrifuges). This standard applies to precession unloading centrifuges. JB/T 7241-1994 Technical requirements for precession unloading centrifuges JB/T7241-1994 Standard download decompression password: www.bzxz.net

Machinery Industry Standard of the People's Republic of China
JB/T7241-94
Precession Discharge Centrifuge
Published on July 18, 1994
Technical Conditions
Implementation on July 1, 1995
Ministry of Machinery Industry of the People's Republic of China
Mechanical Industry Standard of the People's Republic of China
Precession Discharge Centrifuge
1 Subject Content and Scope of Application
Technical Conditions
JB/T 724194
This standard specifies the technical requirements, test methods, inspection rules and marking, packaging and storage requirements for precession discharge centrifuges (hereinafter referred to as centrifuges).
This standard applies to precession discharge centrifuges. 2 Reference standards
GB1220
GB1497
GB/T3280
GB4237
GB 4334.1~4334.5
GB9239
GB 9439
GB10894
GB10895
GB 10901bzxz.net
GB/T13306
GB/T13384
JB4385
JB/T7217
ZB177002
3 Technical requirements
3.1 Basic requirements
Steel pressure vessels
Packaging, storage and transportation pictorial symbols
Technical conditions for high-quality carbon structural steel
Basic technical requirements for high-quality carbon structural steel hot-rolled thick plates and wide strips for rotating electrical machines
Stainless steel bars
Basic standards for low-voltage electrical appliances
Technical conditions for alloy structural steel
Cold-rolled stainless steel plates||t t||Hot-rolled stainless steel plate
Test method for corrosion resistance of stainless steel
Determination of allowable imbalance of rigid rotor balance qualityGray iron parts
Determination of sound power level of separation machineryEngineering methodMethod for testing mechanical vibration of centrifuge and separatorMethod for testing performance of centrifuge
General technical conditions for packaging of electromechanical products
General technical conditions for free forgings on hammer
General technical conditions for coating of separation machinery
Technical specification for conventional non-destructive testing of forged welds of centrifuge and separatorTechnical conditions for welding repair of defects of gray iron castings
Centrifuges shall comply with the provisions of this standard and be manufactured in accordance with drawings and technical documents approved by the prescribed procedures. 3.2 Environmental requirements
Under the conditions of ambient temperature of -10~40C and relative air humidity not exceeding 85%, centrifuges shall be able to operate normally. Approved by the Ministry of Machinery Industry on July 18, 1994
Implemented on July 1, 1995
3.3 Performance
JB/T7241-94
3.3.1 The drum speed should not be less than 97% of the rated speed. 3.3.2 When the centrifuge is running idle, the temperature of the main bearing should not be higher than 70℃, and the temperature rise should not be greater than 30℃; when running under load, the temperature should not be higher than 75℃, and the temperature rise should not be greater than 40℃.
3.3.3 The operating current and temperature rise of the motor should not exceed their rated values. 3.3.4 When the centrifuge is running idle, the noise (sound power level) should not be greater than 100dB(A). 3.3.5 When the centrifuge is running idle at rated speed, its vibration intensity should not be greater than 7.1mm/s3.3.6 The production capacity and separation effect of the centrifuge should meet the design requirements. 3.3.7 Under normal use, the average trouble-free working time of the centrifuge shall not be less than 8000h, excluding the time for replacing wearing parts. 3.4 Structural requirements
3.4.1 The centrifuge shall have a processing surface for checking the installation level of the machine. 3.4.2 The centrifuge shall have a location for installing and transporting bolts and slings. 3.4.3 Important loose connection parts shall have anti-loosening measures. 3.4.4 The centrifuge shall have a vibration isolation device.
3.5 Material requirements
3.5.1 The materials used in the centrifuge shall have a factory quality inspection certificate, otherwise the manufacturer shall inspect the materials according to relevant standards and use them only after they are qualified.
3.5.2 Gray cast iron parts shall comply with the provisions of GB9439. 3.5.3 Shaft parts shall comply with the relevant provisions of GB699, GB1220 and GB3077. 3.5.4 The drum assembly, door cover and casing shall comply with the relevant provisions of GB711, GB4237 and GB/T3280. 3.5.5 If the materials used to manufacture the centrifuge need to be substituted, they shall be substituted with materials with similar or better performance, but the design department must agree with them. 3.6 Process requirements
3.6.1 Important castings and welded parts shall be subjected to stress relief heat treatment. 3.6.2 Welding repair of cast iron parts shall be carried out in accordance with the provisions of NJ431. 3.6.3 Important forgings such as the main shaft shall be forged and inspected in accordance with the requirements of not less than Grade V in JB4385. 3.6.4 Parts such as the single fork and short solid shaft of the transmission shaft system shall be subjected to surface hardening treatment. 3.6.5 For welding specimens of austenitic stainless steel drum assemblies with intergranular corrosion resistance requirements, measures must be taken to prevent or eliminate the tendency of intergranular corrosion. The intergranular corrosion test shall comply with the provisions of GB4334.1~4334.5. 3.6.6 The welding of the drum assembly shall be performed by welders who have passed the labor department examination. 3.6.7 The welding of the drum assembly shall be reviewed with the approval of the production and technical department, and the welding of the same part shall not be reviewed more than twice. 3.6.8 The mechanical property test of the welding specimen shall be carried out in accordance with the relevant provisions in Appendix G of GB150. Its mechanical properties shall not be lower than the requirements of the corresponding standards for the parent material.
3.6.9 The weld of the drum assembly shall be inspected by X-ray flaw detection and shall comply with the provisions of ZBJ77002. 3.6.10 After heat treatment, important forgings shall be inspected by ultrasonic flaw detection or magnetic particle flaw detection and shall comply with the provisions of ZBJ77002. 3.6.11 The drum assembly must be dynamically balanced, and the balance accuracy shall not be lower than G6.3. The determination of the allowable unbalance nut shall comply with the provisions of GB9239. The maximum correction amount of dynamic balance shall not exceed 1/400 of the mass of the drum assembly. 3.7 Appearance quality
3.7.1 Welded parts shall not have obvious defects such as pores, cracks, burn-throughs, slag inclusions and incomplete penetration, and welding slag, spatter, etc. shall be removed. 3.7.2 The exposed stainless steel parts of the centrifuge shall be polished or passivated and shall be free of hammer marks and scratches. 3.7.3 The non-machined outer surfaces of carbon steel and iron parts shall be painted, and the coating must comply with the provisions of JB/T7217. 3.8 Safety requirements
3.8.1 All exposed moving parts of the centrifuge shall be covered with protective covers. 3.8.2 The electronic control equipment of the centrifuge shall comply with the provisions of GB755 and GB1497, and have safety protection measures. 2
4 Test method
JB/T7241-94
4.1 The noise of the centrifuge shall be tested in accordance with the provisions of GB10894. 4.2 The vibration intensity of the centrifuge shall be tested in accordance with the provisions of GB10895. 4.3 The performance test of the centrifuge shall comply with the provisions of GB10901. 5 Inspection rules
The centrifuge shall be inspected and qualified by the quality inspection department of the manufacturer and accompanied by a product quality certificate before it can be shipped! 5.1
5.2 The centrifuge shall undergo factory inspection or type inspection. The test items shall be in accordance with the provisions of Table 1. Table 1
No-load operation test
Load operation test
Separation performance test
Start-up test
Operation test
Noise measurement test
Resonance measurement test
Operation test
Noise measurement test
Resistance measurement test
Factory inspection
Note: A——indicates that the test should be carried out, O——indicates that the test should be carried out as required, and ×—indicates that the test is not carried out. 5.3 Factory inspection
Each centrifuge shall be inspected in accordance with Article 5.2. The following documents shall be checked before the test:
Main parts material certificate or inspection report; Flaw detection inspection report of main parts and components: Mechanical properties test report of drum welded specimen: Dynamic balance inspection report of rotating parts:
Inter-product corrosion test report of stainless steel welded parts: Quality certificate of main purchased and supporting parts. 5.4 Type inspection
Type inspection should be carried out in any of the following situations: a.
Trial production and identification of new products or old products transferred to the factory for production; b. After formal production, if there are major changes in structure, materials, and processes that may affect product performance; e.
When the product is resumed after a long-term suspension of production; d.
When the national quality supervision agency proposes a type inspection requirement. 5.5 Test time
5.5.1 The centrifuge idle operation test is carried out at the rated speed, and the operation time should be no less than 4h. 5.5.2 The centrifuge load operation test is carried out under rated working conditions, and the operation time should be no less than 8h. 5.6 Appearance inspection
The appearance quality and protective devices of the centrifuge shall be inspected in accordance with the provisions of Articles 3.7 and 3.8. Special
Type inspection
5.7 Starting test
JB/T 724194
The time and starting current of the centrifuge from starting to rated speed shall meet the design requirements. 5.8 Running test
5.8.1 The speed of the drum shall meet the provisions of Article 3.3.1. 5.8.2 The temperature and temperature rise of the main bearing shall meet the provisions of Article 3.3.2. 5.8.3 The running current and temperature rise of the motor shall meet the provisions of Article 3.3.3. 5.9 Noise measurement test
The noise of the centrifuge shall meet the provisions of Article 3.3.4. 5.10 Vibration measurement test
The vibration intensity of the centrifuge shall meet the provisions of Article 3.3.5. 5.11 Separation performance test
The production capacity and separation effect of the centrifuge under rated working conditions shall comply with the provisions of Article 3.3.6. 6 Marking, packaging and storage
6.1 Marking
6.1.1 The centrifuge shall be fixed with a metal label in an obvious position and comply with the provisions of GB/T13306. The label content shall be: a. Product model and name;
Main technical parameters of the product (drum large end diameter, mm: drum rotation speed, i/min: drum revolution speed, r/min; main motor power, kW, centrifuge mass, kg); c.
Factory number:
Manufacture date:
Manufacturer name.
6.1.2 The centrifuge shall be fixed with a label indicating the direction of drum rotation in an obvious position. 6.1.3 The label on the outside of the packaging box shall comply with the provisions of GB191. 6.2 Packaging
The packaging of the centrifuge shall comply with the provisions of GB/T13384. 6.2.1
The accessories, spare parts, tools and the surface of the main machine of the centrifuge that are susceptible to atmospheric erosion shall be treated with anti-rust treatment before packaging. 6. 2. 2
The accompanying documents shall be fixed in the main machine box. The accompanying documents are: packing list:
Product certificate:
Product manual (including installation drawings); list of random accessories and accessories.
The centrifuge shall be firmly fixed in the box and shall not be inverted or rolled during the shipping process. 6.2.5 The random accessories, spare parts and special tools shall be fixed in the box and shall not be rolled to avoid loss and damage during transportation. 6.3 Storage
The centrifuge shall be stored in a sheltered place with a relative humidity not exceeding 859%, a temperature below 40C, no corrosive media. 7 Quality Assurance Period
If the user complies with the storage, installation and operation regulations in the product manual, within one year from the date of shipment from the manufacturer, if the centrifuge is damaged or fails to work properly due to poor manufacturing quality, the manufacturer shall be responsible for free repair or replacement (excluding wearing parts). Additional Notes:
JB/T7241-94
This standard is proposed by the National Technical Committee for Separation Machinery Standardization. This standard is under the jurisdiction of the Hefei General Machinery Research Institute of the Ministry of Machinery Industry. This standard was drafted by the Machinery Factory of Jilin Chemical Industry Company. The main drafter of this standard is Yue Simin.
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