PYHL-14A mixed flow smoke exhaust fan

Selection of smoke exhaust fan:
Select the required airflow for the fan based on the size of the kitchen space and the arrangement of the exhaust hood
The calculation method is as follows:
1. Overall exhaust volume, based on kitchen space, with 40-60 air changes per hour.
For example, the total area of the kitchen is 160 square meters and the height is 3 meters. The required ventilation rate is 160X3X60=28800m3/h.
2. Based on the windward side of the kitchen exhaust hood (the circumference of the exhaust hood minus the length against the wall), the wind speed is around 0.5 meters per second.
For example, the perimeter of the kitchen exhaust hood is 25 meters, with a length of 10 meters against the wall. The required ventilation rate is 3600X (25-10) X0.5=27000 m3/h
2： Calculate the required static pressure for the fan based on the condition of the pipeline:
1. Determine the cross-sectional area of the air duct based on the air volume and wind speed (around 10-15 meters per second). The width to height ratio of the air duct should not exceed 2:1 (to save materials and reduce air resistance).
2. Calculate the wind resistance (i.e. the static pressure required by the fan) based on wind speed, duct cross-sectional area, bends, diameter changes, and other factors.
3： According to the calculated air volume and static pressure. Choose a suitable fan.
Key points for selection:
The main control parameters for selecting smoke exhaust fans are operating temperature, air volume, total pressure, efficiency, noise, motor power, speed, and shaft power.
The smoke exhaust fan should be able to operate normally for a long time under the condition that the medium temperature is not higher than 85 ℃.
The smoke exhaust fan should ensure that it can work continuously for 30 minutes when the temperature of the conveying medium is at 280 ℃, and can continue to operate normally when the medium temperature cools down to ambient temperature.
At rated speed, the measured pressure curve of the ventilation fan in the working area should meet the following requirements compared to the curve given in the manual:
The deviation of the pressure value corresponding to the axial flow smoke exhaust fan at the specified flow rate is ± 5%.
The deviation of the pressure value corresponding to the centrifugal smoke exhaust fan at the specified flow rate is ± 5%.
The specific A-level noise limit of the smoke exhaust fan under the given operating conditions in the manual shall comply with the provisions of JB/T8690-1998.
The smoke exhaust fan can be a conventional steel centrifugal fan or a dedicated smoke exhaust axial fan. The specifications of the smoke exhaust fan shall comply with the provisions of the "Code for Fire Protection Design of High rise Civil Buildings". The minimum air volume of the smoke exhaust fan is 7200m/h, and the maximum air volume should not exceed 60000m/h (referring to the maximum air volume of a smoke exhaust zone).
The air volume of the smoke exhaust fan should increase by no less than 10% to 20% according to the required air volume value.
The air pressure value of the smoke prevention and pressurization ventilation fan should be calculated according to the most unfavorable loop of the smoke exhaust system, and the residual pressure value in the smoke prevention staircase should be ensured to be 40-50 Pa. The residual pressure value in the front room, shared front room, fire elevator front room, refuge floor, etc. should be 25-30 Pa.
The fire smoke exhaust fan should comply with the current standard JB/T10281-2001 "Technical Conditions for Fire Smoke Exhaust Ventilators".
The fan of the smoke exhaust system should be separately installed. The position of the smoke exhaust fan should be on the same or upper floor of the smoke exhaust area.
Test method:
The impeller cutting balance correction shall be carried out on the dynamic balancing machine in accordance with the provisions of 7BIT 9101.
The overspeed test of the impeller shall be conducted in accordance with the provisions of 7BIT 6445.
The mechanical operation test of the fire exhaust fan was carried out continuously at the specified speed in the manual. After the bearing temperature stabilized for 20 minutes, the bearing's m rise and vibration were measured. A shall not exceed a temperature of 4nC, and the vibration detection of 99 and its m value shall comply with the relevant regulations of 7Bfr 96V.
The aerodynamic performance test of the fire exhaust fan shall be conducted in accordance with the provisions of GB+T 1236.
The noise measurement method for acoustic testing shall be carried out in accordance with the provisions of CB/r 2888. The noise limit should comply with the provisions of 7BIT 8690.
The high temperature resistance test shall be conducted by inserting the rod according to GA211 regulations. The requirement for high field crystal performance is 4.42.