This standard specifies the classification, technical requirements, test methods, inspection rules, marking, packaging and storage of air volume control valves. This standard applies to rectangular air valves used to change the air volume of the system in ventilation and air conditioning systems, and circular air valves should also be used as a reference. This standard does not apply to air valves used in dust removal systems. JB/T 7228-1994 Air Volume Control Valve JB/T7228-1994 Standard Download Decompression Password: www.bzxz.net

Mechanical Industry Standard of the People's Republic of China
Subject content and scope of application
JB/T 7228--94
This standard specifies the classification, technical requirements, test methods, inspection rules, marking, packaging and storage of air volume control valves (hereinafter referred to as air valves).
This standard applies to rectangular air valves used to change the air volume of the system in ventilation and air conditioning systems, and circular air valves should also be used as a reference. This standard does not apply to air valves for dust removal systems. 2 Reference standards
GB/T1804 General tolerances
Unspecified tolerances for linear dimensions
GB/T13306 Signs
ZBJ72017 Technical conditions for painting of heating, ventilation and air conditioning equipment ZBJ72026 General technical conditions for packaging of heating, cooling and ventilation equipment 3 Terms
3.1 Leakage rate
The leakage rate of an air valve refers to the ratio of the leakage air volume when the air valve is fully closed to the air volume passing through when the air valve is fully open. 3.2 Opening degree
The opening degree of the air valve refers to the percentage of the air flow cross-sectional area after the blade angle changes to the actual flow cross-sectional area when fully open. The angle between the blade and the axis of the air duct can also be used to represent the opening degree of the air valve for split-type multi-leaf air valves, parallel multi-leaf air valves and butterfly valves. 3.3 Air volume ratio
The air volume ratio refers to the percentage of the air volume measured after the blade angle changes to the air volume when fully open. 3.4 Resistance characteristics
The resistance characteristics of the air valve refer to the ratio of the static pressure difference before and after the air valve to its corresponding dynamic pressure (velocity head). 4 Classification
4.1 According to the movement mode of the air valve blades, it is divided into four categories: split-type multi-leaf air valve;
parallel multi-leaf air valve;
diamond blade air valve;
butterfly valve.
4.2 Model designation method
Approved by the Ministry of Machinery Industry of the People's Republic of China on July 18, 1994 and implemented on July 1, 1995
Model example:
JB/T 7228-—94
Damper drive mode: D for electric, Q for pneumatic, S for manual, DS for electric and manual, QS for pneumatic and manual. Air valve height: the inner opening size in the direction of the number of blades, expressed in Arabic numerals, mm
Air valve width: the inner opening size in the axial direction of the blade, expressed in Arabic numerals, mm
Air valve temperature resistance grade code: 1 for working temperature of -40~95℃, 2 for working temperature of 55~205℃. Air valve blade movement mode code: D for split type, P for parallel type, L for diamond type, and no code for butterfly valve. Air valve code
FP2-1000×500D
Indicates parallel multi-leaf electric air valve, working temperature of -55~205℃, width 1000mm, height 500mm. 5 Technical requirements
The air valve shall be manufactured in accordance with the provisions of this standard and the drawings and technical documents approved by the prescribed procedures. 5.1
5.2 The air temperature range of the air flowing into the air valve is: Level 1: -40~~95C;
Level 2: -55~205C.
5.3 The air valve shall be made of galvanized steel plate, aluminum alloy profile, stainless steel or other materials that can meet its use requirements. 5.4 After the whole air valve is installed, it should be firmly connected and open and close flexibly. Each rotating part should rotate smoothly without obstruction and collision. 5.5 The blades of the air valve should be perpendicular to the flow section when fully open and parallel to the flow section when fully closed. 5.6 After the whole air valve is installed, the difference between the lengths of the two diagonals of each face should not be greater than the provisions of Table 1. The flatness tolerance of the flange planes at both ends of the air valve shall comply with the provisions of Table 2.
Diagonal length
Difference between two diagonals
Long side of the air valve end face
Tolerance value
≤1000
≥1 000～1 500
>1 000～~1 500
5.7The tolerance of the width and height of the air valve shall comply with the m grade specified in GB/T1804. >1 500～2 000
>1 5002 000
5.8The leakage rate of ordinary air valves shall not exceed 2%, and the leakage rate of closed air valves shall not exceed 0.5%. 5.9The maximum driving torque of the air valve shall comply with the provisions of Table 3. 1352
>2 000
Air valve height
>500~～750
>750～1 000
>1 000~1 250
>1250~1500
>1 500~1 800
JB/T 7228—94
Air valve widthmm2
>500～750
>750-1 000
>1 000~1 250>1 250~1 500|≥1 500~1 80010. 0
5.10The maximum working pressure difference of the air valve shall be determined by the manufacturer based on the structural material or actual measurement. The air valve shall work continuously within the working temperature range and under the marked working pressure difference without affecting its air tightness and the normal operation of the driving device. 5.11 The air valve shall not produce vibration and abnormal noise under the flow rate conditions specified in the manufacturer. 5.12 For air valves using a driving device, its driving device shall ensure that the air valve operates normally under the maximum working pressure difference. 5.13 For air valves operated by handwheels (including handwheels of driving devices) or wrenches, the air valve shall be closed when it is turned clockwise facing the handwheel or wrench. 5.14 The air valve shall have an indication mechanism to indicate the opening and a limit mechanism to ensure the full open and full closed positions of the air valve. Manual air valves shall also have a locking mechanism to maintain any opening.
5.15 The surface treatment of the air valve shall comply with the provisions of ZBJ72017. 5.16 Under the condition that the user complies with the provisions in the product manual, within 18 months from the date of shipment from the manufacturer, or when the actual use time does not exceed 12 months, if the air valve is damaged or cannot work normally due to poor manufacturing quality, the manufacturer shall repair or replace it free of charge. 6 Test methods
Damper test items
Inherent regulating characteristics;
Resistance characteristics;
Leakage rate,
Maximum driving torque;
Maximum working pressure difference.
6.2 The test equipment for 6.1a and 6.1b shall be in accordance with Appendix A (reference), and the test equipment for 6.1c, 6.1d and 6.1e shall be in accordance with Appendix B (reference).
6.3 Test conditions and methods
6.3.1 The tests for 6.1a and 6.1b can be carried out at room temperature, and the tests for 6.1c, 6.1d and 6.1e shall be completed within 15 minutes after the damper is placed at the corresponding temperature resistance level for 2 hours.
6.3.2 When testing the inherent regulating characteristics, change the damper opening, test the corresponding flow, and keep the static pressure difference on both sides of the damper unchanged. The static pressure difference on both sides when the tested air valve is fully opened and the flow rate is 20m/s is used as the static pressure difference during the test. The inherent adjustment characteristic curve is drawn with the air valve opening as the horizontal coordinate and the air volume ratio as the vertical coordinate. 6.3.3 When testing the resistance characteristic of the air valve, the static pressure difference before and after the air valve and its corresponding air volume are measured by changing the air valve opening, and the resistance characteristic curve is drawn with the air valve opening as the horizontal coordinate and the air valve resistance coefficient as the vertical coordinate. 6.3.4 When measuring the leakage rate of the air valve, the air valve should be closed and the static pressure difference before and after it should comply with the provisions of Table 41353
Air valve width
>500～750
>750-1 000
>1 000-1 250
>1250~～1500
>1500～1800
JB/T 7228—94
Static pressure difference on both sides of the air valve
When measuring the maximum driving torque of the air valve, the static pressure difference on both sides of the air valve after the air valve is closed should be equal to its maximum working pressure difference. 6.3.5
6.3.6: When determining the maximum working pressure difference of the air valve, the maximum static pressure difference that can be tolerated without affecting the air tightness of the air valve (leakage rate 2% or 0.5%) and meeting the conditions of not exceeding the maximum driving torque (see Table 3) measured on the test bench (see Appendix B) shall be used. 7
Inspection rules
7.1 Type inspection shall be carried out in any of the following situations: a.
When the old product is discontinued for more than two years and then resumes production; when the new product is trial-produced;
When there are major changes in the process, structure, and materials that may cause changes in product performance. 7.2 The items for type inspection are shown in Table 5.
7.3 The items for random inspection are shown in Table 5.
A random inspection shall be conducted once every quarter, and two units of each type shall be inspected. If one unit fails to meet the standards, a full inspection shall be conducted. The items for factory inspection are shown in Table 5.
Each air valve shall be inspected before leaving the factory. Table 5
Inspection itemswwW.bzxz.Net
Appearance inspection
Inherent adjustment characteristics
Resistance characteristics
Leakage rate
Maximum driving torque
Maximum working pressure difference
8 Marking, packaging and purchase and storage
8.1 Marking
Articles 5.3~5.7 and 5.11~~5.15
8.1.1A label shall be fixed on each air valve in an obvious position. The size and technical requirements of the label shall comply with the provisions of GB/T13306. The following information shall be marked on the label at least:
Manufacturer name;
Model and specification;
Maximum working pressure difference;
Factory number and date of manufacture.
JB/T 7228--94
8.1.2 The air valve shall have obvious markings for airflow direction and opening and closing. 8.2 Packaging
8.2.1 The packaging of the air valve shall comply with the provisions of ZBJ72026. 8.2.2 The following documents shall be included in the packaging box: a. Product certificate:
h. Product manual, including: product model, name, working principle, performance parameters, inherent adjustment characteristic curve, resistance characteristic curve, maximum working pressure difference, product structure, installation diagram, installation instructions and requirements, instructions for use, maintenance and care precautions. 8.3 Storage
The air valve should be stored in a ventilated and dry warehouse or shed, and should be protected from knocks and corrosion by corrosive gases. 1355
JB/T7228—94
Appendix A
Air valve test device 1
(reference part)
1-ventilator: 2-gate valve; 3-way; 4-gate valve; 5-air duct: 6-round sky and square ground; 7-tested air valve; 8-air inlet pipe; 9-static pressure ring; 10-inclined micromanometer Figure Al
Air storage bag
JB/T7228—94||t t||Appendix B
Damper test device 2
(reference)
Differential pressure transmitter
1-compressed air storage bag; 2-manual valve; 3-standard orifice flowmeter (measurement accuracy 0.5 level): 4-pressure gauge; 5-pressure regulator: 6-electric valve; 7: tested damper; 8-static pressure box
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 Sixth Design Institute of the Ministry of Machinery Industry and Beijing Instrument Machine Tool Factory. The drafters of this standard are Luo Yingxin and Lu Ping. 1357
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