Some standard content:
Light Industry Standard of the People's Republic of China
RHF Series Dairy Directional Valve
1 Subject Content and Scope of Application
QB/T 1675--1992
This standard specifies the terminology, product classification, technical requirements, test methods, inspection rules and marking, packaging, transportation and storage of RHF series dairy directional valves.bZxz.net
This standard applies to RHF series dairy directional valves used for fluid materials without solid particles in the dairy, food and beverage processing industries.
2 Reference standards
GB/T191 Pictorial symbols for packaging, storage and transportation
GB4807 Hygienic standard for rubber gaskets (rings) for food GB12073 Safety and hygiene of dairy equipment
JB/T8 Product labels
JB/T302 Classification of casting defect names
JB/T2759 General technical conditions for packaging of electromechanical products JB/LQ20703 Test method for pneumatic-reversing valves QB/T1823 Method for compiling dairy machinery models 3 Terminology
3.1 Dairy reversing valve: In the process of dairy product processing, a valve used to switch the flow direction of materials and cleaning liquids to transport materials and cleaning liquids (hereinafter referred to as "reversing valve"). 3.2 Pneumatic electromagnetic milk reversing valve: a milk reversing valve that uses compressed air as the power medium and is controlled by a pilot solenoid valve (hereinafter referred to as "pneumatic valve")
3.3 Manual milk reversing valve: a milk reversing valve that is controlled by hand twisting (hereinafter referred to as "manual valve"). 4 Product classification
4.1 Product varieties, types, specifications
a. According to the outer diameter of the pipe, there are seven specifications: 25, 32, 40, 5065, 76, 89mm, b. According to the structural type, there are six types: one-position two-way (L type), one-position three-way (T type), two-position three-way (LL type), two-position four-way (TL type and LT type) and two-position five-way (TT type), c.
According to the connection method, there are three types: threaded (slip joint) connection, flange connection and welding connection; d. According to the control mode, there are two types: pilot electromagnetic pneumatic control and manual control; according to the open and close state, there are two types: normally open and normally closed. e.
4.2 Model representation method
The model is compiled in accordance with the requirements of QB/T1823 and combined with product characteristics. Approved by the Ministry of Light Industry of the People's Republic of China on January 15, 1993 and implemented on September 1, 1993
HF-□
Note: Manual valves do not open or close.
Marking example:
RHF-Q23-L50K type milk reversing valve
QB/T 1675—1992
Opening and closing state: B-normally closed
K-normally open
Outer diameter of pipe: 25, 32, 40, 50, 65, 76, 89mm Connection method: L-threaded connection
F-flange connection
H-welded connection
Structure type: 12-position two-way (L type)
13--one-position three-way (T type)
23-two-position three-way (LL type)
24—2-position 4-way (TL or LT type)
25—2-position 5-way (TT type)
Control mode: Q—pilot electromagnetic pneumatic control S—manual control
Directional control valve
Dairy machinery
Indicated as: 2-position 3-way normally open pneumatic dairy directional control valve with a pipe outer diameter of 50 mm and a threaded connection; RHF-S24-F40 dairy directional control valve
Indicated as: 2-position 4-way manual dairy directional control valve with a pipe outer diameter of 40 mm and a flange connection. 4.3 Models and basic parameters
4.3.1 The models and basic parameters of pneumatic valves shall comply with the provisions of Table 1. 4.3.2
The models and basic parameters of manual valves shall comply with the provisions of Table 2. Table 1
Basic parameters
Outer diameter of pipe
Power medium
Medium fluid material
Air source working pressure MPa
Maximum switching frequency
Switching time
Fluid material pressure
Material rated flow m/h
Q13 LB
RHF-Q23-F25 RHF-Q23-F32 RHF-Q23-F50|RHF-Q23-F50|RHF-Q23-F65 RHF-Q23-F76|RHF-Q23-F89Q24HK
Filtered compressed air
Milk, beer, soda, juice and ≤3% nitric acid, ≤3% sodium hydroxide, etc. 0.6~0.8
Basic parameters
Rated flow rate of materials
Liquid sodium hydroxide
Leakage
Durability
QB/T1675—1992
Continued Table 1
Q13 LB
Q13 LB
RHF-Q23-F25RHF-Q23-F32 RHF-Q23-F50|RHF-Q23-F50|RHF-Q23-F65|RHF-Q23-F76RHF-Q23-F89Q24HK
Basic parameters
Outer diameter of pipe
Fluid material
Fluid material pressure MPa
Material rated flow m/h
Material rated flow rate
Liquid sodium hydroxide
Leakage
Durability
5 Technical requirements
RHF-S23-F25
RHF-S23-F50 RHF-S23-F65 RHF-S23-F76 RHF-S23-F89RHF-S23-F32
2RHF-S23-F40
Milk, beer, soda, juice and ≤3% nitric acid, ≤3% sodium hydroxide, etc. ≤0.4
Directional valves shall comply with the requirements of this standard and be manufactured according to drawings and technical documents approved by the prescribed procedures. 5.1
5.2The materials of the parts in contact with the materials of the reversing valve shall comply with the provisions of GB12073. 25
5.3The reversing valve casting shall not have various defects that affect the strength and other properties of the casting as specified in JB/T302. The molding sand and 279
burrs on the surface and inner cavity of the casting shall be cleaned.
QB/T 1675—1992
5.4 The welded parts of the reversing valve must be welded by argon arc welding. The weld should be smooth and flat, and the sealing and strength requirements should be guaranteed. 5.5 The surface roughness R of the reversing valve surface in contact with the material shall not exceed 1.6μm, and obvious defects such as unevenness, spots, scratches, etc. are not allowed. The excessive fillet should be smooth, and the polished surface texture should be neat and beautiful. 5.6 The rubber seals used in the valve body of the reversing valve should meet the health standards specified in GB4807 and be resistant to 5% nitric acid, 5% sodium hydroxide, oil (bio-oil), heat (95℃ hot water) and non-toxic, odorless and pollution-free. 5.7 Normal working conditions of reversing valve
5.7.1 Normal working conditions of pneumatic valve:
Dry compressed air containing oil mist after being treated by a filter with a filtration degree of 25~～50μm and a water separation efficiency of not less than 80%; a.
b. Working environment temperature: 5~55℃,
c. The relative humidity of the surrounding air is not more than 90%. 5.7.2 Normal working conditions of manual valve:
a. The adjustment thread should be smooth, the thread tightness should be moderate, and the rotation should be flexible; b. After tightening the handle, the rubber seal should seal the corresponding valve port and sealing surface, and there should be no leakage at all joints. 5.8 Pressure resistance
The cylinder of the pneumatic valve is maintained at 1.5 times the rated working pressure for 5 minutes, and the valve body of the pneumatic valve and the manual valve are maintained at 1.5 times the material working pressure for 5 minutes. No defects such as leakage and cracking shall occur in any parts and seals. 5.9 Switching performance
Under the working conditions specified in this standard, the pneumatic valve should have a fast and smooth switching action without any abnormal sound or abnormal phenomenon. 0 Valve port sealing performance
Under the working conditions specified in this standard, the pneumatic valve should be able to seal the valve port to be sealed before or after work, and the manual valve should be able to seal the valve port to be sealed after tightening the handle clockwise or counterclockwise, and there should be no leakage. 5.11 Anti-performance
When the pneumatic valve is in a vertical working position, it should be able to withstand the working environment vibration with a frequency of 20Hz and a full amplitude of 2mm. During vibration or after vibration for 30 minutes, its switching performance and sealing performance should still meet the requirements of this standard. 5.12 Durability
After the reversing valve has worked for a long time for a specified number of times, its technical performance should still meet the requirements of this standard. 5.13 The outer surface of the reversing valve needs to be polished, and the polishing lines should be neat and beautiful, bright and smooth. The outer surface should not have defects such as scratches and damage; fasteners should not be loose.
6 Test method
6.1 The maximum reversing frequency, reversing time, sealing performance, pressure resistance, reversing performance, vibration resistance and durability of pneumatic valves should be carried out in accordance with the provisions of JB/LQ20703.
6.2 The performance test method of manual valves is as follows: 6.2.1 Pressure resistance performance test
Seal the outlet of the tested valve, put the valve in each working position, and pass the test pressure gas of 1.5 times the material pressure from the inlet, and maintain the pressure for 5 minutes.
6.2.2 Sealing performance test
Pass the specified test pressure gas at the inlet of the tested valve, and measure the internal leakage between the two disconnected ports at the outlet. 6.2.3 Flexibility test
Shake the handle to check, the rotation should be flexible and there is no jamming. 6.3 The hygienic standards and acid and alkali resistance test results of the rubber seals of the reversing valve shall comply with the provisions of Article 5.6. The acid and alkali resistance test methods are as follows:
TiKAONKA
QB/T1675—1992
Put the rubber seals that have been tested and meet the requirements of the drawings into 5% nitric acid and 5% sodium hydroxide solutions respectively, soak them at room temperature for three months, and then take them out for testing. Their size, shape and hardness should meet the requirements of the drawings; b. Interchange the solutions of the two parts of the rubber seals that have been soaked in 5% nitric acid and 5% sodium hydroxide and soak them for another three months. Take them out and then test them again. The difference should still meet the requirements of item a of this article. 7 Inspection rules
7.1 Factory inspection
The factory inspection of pneumatic valves shall be carried out in accordance with the requirements of 5.1, 5.3, 5.4, 5.5, 5.6, 5.7.1, 5.8, 5.9, 5.10, 5.13. The factory inspection of manual valves shall be carried out in accordance with the requirements of 5.1, 5.3, 5.4, 5.5, 5.6, 5.7.2, 5.8, 5.10, 5.13. After passing the inspection, the competent quality inspection department shall issue a certificate of conformity before the product can be shipped.
7.2 Type inspection
It shall be carried out in one of the following situations.
When a new product is put into production,
When there are major changes in the design, process or materials used, which may affect the product performance; when the product is put into production again after being discontinued for more than one year,
d. During normal production, it is conducted once every two years; e.
When the national quality supervision agency proposes the requirement for type inspection. 7.3 Type inspection items and sampling rules
7.3.1 Inspection shall be conducted according to all the contents in this standard. 7.3.2 Sampling shall be conducted according to 10% of the production batch, but at least 1 unit. 7.4 Type inspection judgment method
According to the provisions of Article 7.3.1, all products are qualified products. If the inspection fails, double sampling shall be conducted. If it still fails, the batch of products shall be regarded as unqualified.
8 Marking, packaging, transportation, storage
8.1 Marking
8.1.1 Product marking
Directional valves shall be fixed with signs in obvious places. The form and size of the signs shall comply with the provisions of JB/T8. 8.1.2 Packaging Marking
The packaging marking shall comply with the provisions of GB/T191
8.2 Packaging
8.2.1 The product packaging shall comply with the provisions of JB/T2759. 8.2.2 The packaging box shall be accompanied by the following documents:
a. Product instruction manual;
b, product certificate;
c. Packing list.
8.3 Transportation
The reversing valve shall not be allowed to collide during transportation. 8.4 Storage
The reversing valve shall be stored in a clean and dry warehouse to avoid coexistence with nitrides. 281
Additional Notes:
This standard is proposed by the Technical Equipment Department of the Ministry of Light Industry. QB/T1675—1992
This standard is under the jurisdiction of the National Dairy Machinery Standardization Center. This standard was drafted by the Harbin Machinery Research Institute. The main drafters of this standard are Zhao Xuejun and Wang Zhikang.
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