This standard specifies the main types, technical requirements, test methods, inspection rules and other requirements of mechanical seals for boiler feed pumps. JB/T 6614-1993 Technical requirements for mechanical seals for boiler feed pumps JB/T6614-1993 Standard download decompression password: www.bzxz.net

Machinery Industry Standard of the People's Republic of China
JB/T 6614-1993
Mechanical seals for boiler feed pumps
Technical conditions
Published on 1993-05-07
Ministry of Machinery Industry of the People's Republic of China
Implementation on 1994-01-01
Mechanical Industry Standard of the People's Republic of China
Mechanical seals for boiler feed pumps
Technical conditions
Subject content and scope of application
JB/T 66141993
This standard specifies the main types, technical requirements, test and inspection methods, inspection rules and other requirements for mechanical seals for boiler feed pumps. This standard applies to heavy-duty mechanical seals used in boiler feed pumps with boiler water temperature not higher than 260℃. Its working parameters are: a.
Sealing medium: boiler water:
Seal chamber pressure: ≤5MPa;
Seal chamber temperature: 0~70℃:
Shaft diameter: ≤250mm;
Linear speed: ≤70m/s.
Referenced standards
GB1184
GB1801
GB2828
JB4127
JB4236
JB/T6374
ZBJ22002
ZB J22 004
ZBJ22 017
3 Type
Packaging, storage and transportation Pictograms and signs
Shape and position tolerances Specified tolerances and fits for dimensions without tolerances up to 500mm Tolerance zones and fits for holes and shafts Inspection by batch counting Sampling procedures and sampling tables (applicable to inspection of continuous batches) Technical conditions for mechanical seals
Mechanical seals
Test methods
Silicon carbide sealing rings for mechanical seals
Technical conditions
O-rings for mechanical seals
Cylindrical helical springs for mechanical seals
Carbon graphite sealing rings for mechanical seals
Technical conditions
Mechanical seals for boiler feed pumps should generally be single-end, built-in, multi-spring, balanced, static, or single-end, fluid dynamic pressure type.
4 Technical requirements
4.1 Mechanical seals for boiler feed water pumps shall comply with the provisions of this standard and be manufactured according to drawings and technical documents approved by the prescribed procedures. 4.2 Technical requirements for main parts
4.2.1 The flatness of the sealing end faces of the rotating ring and the stationary ring is 1.1μm (3.5 light bands), and the surface roughness R, value is 0.2μm. 4.2.2 The dimensional tolerance band of the contact part between the rotating ring and the stationary ring and the auxiliary sealing ring shall be in accordance with the 8th grade accuracy in GB1801, and the surface roughness R. value is 3.2μm.
Approved by the Ministry of Machinery Industry on May 7, 1993
Implemented on January 1, 1994
JB/T6614-1993
4.2.3 The parallelism of the sealing end faces of the rotating ring and the stationary ring to the end faces in contact with the auxiliary sealing ring shall be in accordance with the 7th grade tolerance in GB1184. 4.2.4 The verticality of the sealing end face of the rotating ring and the stationary ring to the outer circle or inner hole in contact with the auxiliary sealing ring shall comply with the 7th grade tolerance in GB1184.
The impregnated carbon graphite ring and the mounted combined sealing ring shall be subjected to a hydrostatic pressure test. The test pressure shall be 1.25 times the working pressure and shall last for 10 minutes without leakage.
4.2.6 The technical requirements for O-shaped rubber rings shall comply with the provisions of ZBJ22002. 4.2.7 The technical requirements for springs shall comply with the provisions of ZBJ22004. For multi-spring mechanical seals, the free height difference between the springs in the same set of mechanical seals shall not exceed 0.5mm.
4.2.8 The limit deviation of the un-toleranced dimensions of the parts shall comply with the IT12 grade tolerance in GB1184. 4.3 Material requirements
4.3.1 The material of the carbon graphite sealing ring shall comply with the provisions of ZBJ22017. 4.3.2 Silicon carbide sealing ring materials shall comply with the provisions of JB/T6374. 4.3.3 Other materials shall comply with the provisions of relevant standards or technical documents. 4.4 Performance requirements
4.4.1 Leakage
Under stable operating conditions, the average leakage is specified as follows: internal static mechanical seal: ≤100mL/h; fluid dynamic pressure type mechanical seal: ≤500mL/h. The leakage is allowed to exceed the specified value during the initial running-in operation, but the leakage trend must be gradually reduced. 4.4.2 Wear
After a certain period of operation of the mechanical seal, the wear of any sealing ring sealing end face should not exceed 0.02mm/100h. 4.4.3 Service life
Under the condition of correct implementation of the installation and use requirements, the service life shall not be less than 8000h. 5 Test and inspection methods
New products shall be subjected to type tests in accordance with JB4236 5.1
5.2 Before finalized products leave the factory, they shall be subjected to factory tests in accordance with JB4236. The flatness of the end face of the sealing ring shall be inspected with a Class 1 optical flat crystal and a monochromatic light source. 5.3
The surface roughness of the end face of the sealing ring shall be measured with a surface roughness measuring instrument or a sample block comparison method. 5.5 The inspection of other parts shall be carried out in accordance with relevant standards. 6
Inspection rules
Mechanical seals for boiler feed water pumps shall be inspected and qualified by the inspection department of the manufacturer before they can leave the factory. 6.2 The factory inspection items are all the contents of Articles 4.1 to 4.3. 6.3 In any of the following circumstances, Article 4.4 shall be inspected: Newly designed products:
b. The product is transferred to another factory for production;
Continuous production for five years;
d. The superior quality supervision agency requires inspection JB/T 6614-1993
6.4 Mechanical seals for boiler feed water pumps are sampled and inspected according to the one-time sampling plan specified in GB2828, with a special inspection level of S-4 and an AQL of 4.0. They can only leave the factory after passing the inspection.
7 Installation and use requirements
7.1 The shaft (or sleeve) where the mechanical seal is installed and the requirements for the seal end cover or housing are in accordance with the relevant provisions of JB4127.7.2 The axial motion of the rotor is not more than 1mm. 7.3 When installing the mechanical seal, the installation size of the mechanical seal should be guaranteed according to the product installation and use instructions. 7.4 When installing and using the mechanical seal for boiler feed water pumps, the corresponding seal circulation protection system must be equipped to control the temperature in the seal cavity below 70℃. When the user needs it, a temperature monitoring instrument and an overheating protection device must be added. 7.5 When the boiler feed water pump is in standby mode, the cooling water in the system should continue to be supplied, and the cooling water volume should ensure the design specified amount. 8 Marking, packaging and storage
The product should have the manufacturer's mark.
8.2 The product should be cleaned and rust-proofed before packaging. 8.3 The complete set of products should be packed in a special packaging box. The packaging box should indicate the product name, model, specifications and manufacturer's name. 8.4 The product packaging box should be accompanied by a product certificate. The certificate should indicate the product model, manufacturer's name, signature and date of the inspection department and inspector.
8.5 The packaging, storage and transportation graphic signs should be correctly selected according to the provisions of GB191. 8.6 The packaging should prevent damage, deformation and rust of the product during transportation and storage. 8.7 The relevant technical documents include: packing list, installation and use instructions, installation drawings, etc., which should be packed together in a moisture-proof plastic bag and sealed, and placed in the packaging box together with the product. Www.bzxZ.net
Additional instructions:
This standard was proposed and managed by the Hefei General Machinery Research Institute of the Ministry of Machinery Industry. This standard was drafted by the Shenyang Mechanical Seal Research Institute. The main drafters of this standard are Cao Hongqin and Shi Xueli. 3
People's Republic of China
Mechanical Industry Standard
Mechanical Seals for Boiler Feed Pumps
Technical Specifications
JB/T 66141993
Published and issued by the China Academy of Mechanical Science
Printed by the China Academy of Mechanical Science
(No. 2 Shouti South Road, Beijing
Format 880×12301/16
First edition in October 1993
Postal Code 100044)
Sheet 1/2Number of words 6.000
First edition in October 1993
Sold once
Number of prints 1-500
Price 2.00 Yuan
Mechanical Industry Standard Service Network: http://www.JB.ac.cn699
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