This standard specifies the product classification, product marking, technical requirements, inspection rules and marking, packaging, transportation and storage requirements of plastic cooling fans for internal combustion engines. JB/T 6723.2-1993 Internal combustion engine cooling fans Part 2 Technical conditions for plastic cooling fans JB/T6723.2-1993 Standard download decompression password: www.bzxz.net

Mechanical Industry Standard of the People's Republic of China
JB/T6723.2-1993
Cooling Fans for Internal Combustion Engines
Part 2
Published on July 29, 1993
Technical Conditions for Plastic Cooling Fans
Implemented on January 1, 1994
Ministry of Machinery Industry of the People's Republic of China
Mechanical Industry Standard of the People's Republic of China
Cooling Fans for Internal Combustion Engines
Part 2 Technical Conditions for Plastic Cooling Fans Subject Content and Scope of Application
JB/T6723.21993
This standard specifies the product classification, product marking method, technical requirements, inspection rules, marking, packaging, transportation and storage of plastic cooling fans for internal combustion engines.
This standard applies to water-cooled and oil-cooled plastic cooling fans for internal combustion engines (hereinafter referred to as fans) with an outer diameter not exceeding 750mm. Cited standards
GB1236
GB1801
GB2828
Test methods for aerodynamic performance of ventilators
Tolerances and fitsDimensions up to 500mm holes, shaft tolerance zones and fitsBatch-by-batch inspectionCount sampling procedures and sampling tables (applicable to inspection of continuous batches)Product classification, product marking method
The classification of fans is shown in Table 1 and Figure 1.
Classification and code of fans
Classification by airflow direction
Direction of rotation
Airflow direction
Forward fan
Approved by the Ministry of Machinery Industry on 1993-07-29
Forward fan
Reverse fan
Fan classification
Direction of rotation
Airflow direction
b Reverse fan
Implementation on 1994-01-01
Product marking method
3.2.1 The product marking consists of the following parts: O00-00
Marking example
JB/T6723.2-1993||tt ||Standard No.
Positioning hole diameter
Fan outer diameter
Classification code
Product name
a. Forward plastic fan, fan diameter 490mm, positioning hole diameter 42mm marked: JB/T6723.2—1993
Plastic fan Z490-42
b. Reverse plastic fan, fan diameter 590mm, positioning hole diameter 45mm marked: Plastic fan F590-45
Technical requirements
JB/T6723.2—1993
Fans should comply with the requirements of this standard and be manufactured according to product drawings and technical documents approved by the prescribed procedures. The positioning hole diameter and bolt hole center circle diameter dimensions are shown in Table 2. Positioning hole diameter and bolt hole center circle diameter (recommended size) Table 2
Positioning hole diameter
See Table 3 for fan outer diameter dimensions.
Fan outer diameter
Fan outer diameter
Bolt diameter
Fan outer diameter
(recommended size)
The dimension tolerance grade of the fan positioning hole shall reach the H9 grade specified in GB1801. The position tolerance of the center of the fan bolt hole is 0.35mm. The fan blade installation angle deviation is ±1°.
Bolt hole center circle diameter
When rotating with the positioning hole and the fan installation plane as the reference, the runout of the blades on the same side on the same diameter shall comply with the provisions of Table 4. 4.8
Fan outer diameter
>350~550
>550~750
JB/T6723.2—1993
Fan blade runout on the same side
Fan assembly shall be subjected to static balance test, and the unbalance amount shall comply with the provisions of Table 5. Table 5 Unbalance amount of fan assembly
Fan outer diameter
>400~500
>500~600
>600~750
Unbalance amount
Fan shall not have color difference, flash, impurities, and the blade surface shall be smooth without depression. Porosity, looseness and other defects shall not be allowed inside the blade and wheel shell, and slight depression is allowed on the wheel shell surface.) Fan plastic parts and metal accessories shall be firmly combined and no looseness is allowed. 4.10
The surface of metal accessories should be treated with anti-rust.
The aerodynamic performance of the fan should comply with the product drawings or relevant standards. The test method adopts the air intake method specified in GB1236. The diameter of the test wind circle should be 1.05 times the outer diameter of the fan (rounded). The axial projection width of the fan blades should be completely within the test wind circle. 2 The fan noise should comply with the product drawings or relevant standards. 4.12
The fan shall be subjected to an overspeed test, the test speed shall be 1.5 times the rated speed, the running time shall be 1min, after the test, no defects such as cracks or looseness shall be found in any part.
The fan shall be subjected to a hot and cold alternating test, the fan shall be operated at rated speed on a hot and cold cycle test bench with airflow temperature at room temperature and 100±2 for 1h respectively as one cycle, after 5 cycles of the test, the increase in the amount of beating of the blades on the same side of the fan shall not be greater than 30% specified in Table 4, the radial elongation of the outer edge of the fan shall not be greater than 0.5% of its outer diameter, and the air volume shall not drop by more than 8% before the test. No defects such as cracks or looseness shall be found in any part of the fan.
4.15The fan shall be subjected to a low temperature test. The fan shall be operated continuously at rated speed for 30min at an airflow temperature of -30±2℃, and no defects such as cracks or looseness shall be found in any part of the fan.
6The life of the fan shall not be less than 5 years under normal use conditions. 4.16
Inspection rules
The fan must be inspected and qualified by the quality inspection department of the manufacturer before it can leave the factory. The factory inspection items shall be carried out in accordance with the provisions of Articles 4.4 to 4.10. Type inspection is required in any of the following situations: a. Product finalization identification;
b. Product structure, materials, and processes have changed significantly; c. After one year of normal production;
d. Resuming production after a long period of suspension;
e. There is a significant difference between the factory inspection or user sampling and the last type inspection; f. Requirements of the superior department.
Inspection items shall be carried out in accordance with the provisions of Articles 4.11 to 4.15. JB/T 6723.21993
5.4 The delivery and acceptance of fans in batches, the delivery and acceptance items are the same as the factory inspection. When the ordering unit conducts random inspection of product quality, it shall be carried out in accordance with the provisions of GB2828, using the general inspection level II, and the qualified quality level AQL value shall be agreed upon by the supply and demand parties. 6
Marking, packaging, transportation, storage
6.1 Each fan shall be marked with:
a. Manufacturer's name or trademark;
b. Product model.
The marking shall be clear and permanent, and the marking position shall be on the non-installation plane side, and the size and method shall comply with the product drawings or technical documents. 6.2 The fan shall be accompanied by a certificate signed by the manufacturer's quality department and inspection personnel when leaving the factory. The certificate shall indicate: a. Manufacturer's name;
b. Product name and model;
c. Inspection date.
6.3 The same model of products shall be packed in the packaging box, and the outside of the box shall be marked with: a. Product name, model and quantity;
b. Manufacturer's name and address;
c. "Handle with care" words or symbols.
6.4 The fan should be securely placed in a cardboard box or wooden box to ensure that it will not be lost or damaged during normal transportation. 6.5 The product manual and packing list should be attached to the packaging box, and the outside of the packaging box should be marked with: a. Product name, model and quantity;
b. Manufacturer's name and address;
c. Gross weight, kg;
d. Receiving unit and address;
e. Date of manufacture:
f. "Handle with care", "Moisture-proof" and other words or symbols. The fan should be placed in a ventilated and dry warehouse, away from fire sources, and avoid contact with acids and alkalis. Under normal maintenance conditions, the manufacturer should6.6
guarantee that the fan will not be deformed within 12 months from the date of manufacture, and the metal accessories will not rust. Additional remarks:
This standard was proposed by the Luoyang Tractor Research Institute of the Ministry of Machinery Industry. This standard is under the jurisdiction of the Shanghai Internal Combustion Engine Research Institute of the Ministry of Machinery Industry. This standard was drafted by the Luoyang Tractor Research Institute of the Ministry of Machinery Industry and the Hangzhou Automobile Engine Factory. The main drafters of this standard are Lu Ziping and Tu Qixing. 4
People's Republic of China
Mechanical Industry Standard
Internal Combustion Engine Cooling Fan
Part 2 Technical Conditions for Plastic Cooling Fans JB/T 6723.21993bZxz.net
Published by the Mechanical Science Research Institute
Printed by the Mechanical Science Research Institute
(No. 2, Shouti South Road, Beijing
Postal Code 100044)
Print Sheet 1/2
Format 880×1230
Word Count 8,000
First Edition December 1993
First Printing December 1993
Print Quantity 1-500
Price 2.00 Yuan
Mechanical Industry Standard Service Network: http://www.JB.ac.cn669
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