As a new product for thermal air duct and air volume adjustment, it embodies the Advantages of ball valve and butterfly valve.lt uses sheet welded dise to stably and precisely adjust the air volume,making flow characteristic approximately to equal percentage. Range of adjustment is up to 100:1.With the use of axial ring and high structure, pipe can be mounted and driven at any position from top or bottom.Specially designed operating frame is featured by easy operation,high flexibility and accurate positioning Drive modes indude worm and gear driven and electric.
（Ⅰ）The following work shallbe done before the valve is installed:
1. Carefully check if the using conditian of the valve is in accordance with its performance specification.
2. Check if there are impurities at the valve channel and sealing surface and eliminate them if any.
3. After unpacking, the valve shall be installed in time. Do not randomlyloasen any fastening screw on the valve.
4.the multilayer metal seal and cast iron sott seal butterfly valves shall be equipped with standard flanges.Others shall be equipped with special flanges for butterfly valve (see figure l) .
5. The installation and commissioning personnel shall read carefully the use instructions, pneumatic and electric operation instructions and carry out installation, operation, commissioning and winng in stnct accordance with the instructions and winng diagrams.
6. When the user requires pressure test, make sure that the valve is well installed through the flanges at the two ends or carry out pressure test on the pressure test workbench (see figure 2) .
7. The butterfly valve shall be at the closing status during the installation. During the welding, the cover plate of valve
channel shall be blocked(see figure 5) to prevent granules and impurities from damaging the sealing surface..
（Ⅱ）The butterfly valve can be installed om the pipe at any angle, but can’t be installed reversely. Vertical or horizontal installation is generally adopted.
（Ⅲ）The butterfly valve is generally for single direction use. During the installation, please notice that the arrow on the valve body indicates the medium pressure direction when the sealing is closed. (see figure 4)
(Ⅳ) When the tlange butterfly valve is installed at the end of the pipe, the end shall be equipped with flange to prevent the seal ring from being extruded.
(Ⅴ) Though the product has been carried out strict inspection and test before leaving the factory, the screw displaycement due to the vibration during the transportation may occur, which shall be readjusted.The justment shall be carried out according to figure 3. If the butterfly plate is not tightly closed, slightly turn the screw 2 cunterclockwise and turn the butterfly plate to the sealing position. After the situation is acceptable, lock the nut. If the butterfly plate is closed too tightly (or the butterfly plate can t be opened), please slighlly turn the screw 2 clockwise, open the butterfly valve and close the sealing position again. After the situation is acceptable, lock the nut. (see figure 3)
(Ⅵ) In order not to make a mistake of the direction when the power is switched on, the opening and closing travels of the control mechanism have been adjusted before the electric buttertly valve leaves the factory. Before switching on the power for the first time, the user shall open the valve manually to the semi- open position and then press the inching switch. Check if the direction of the indication dise is in accordance with the opening direction of the valve.
Possible malfunctions and eliminating methods
| Probably Hitch
| leakage of facing
||1.Sundries clips in dice gasket
2.Disc and gasket out of position
3.Fitting flange bolt on output stresss unequally or clamp not tightly
4.Pressure testing ditecrion not according to requirement of diagram2
|1.Remove sundries, clean inner of valve
2.Adjust bolt of gear wheel or power-operated exacutivo device, so as to close valve correctly
3.Inspect necessary plane of flange and compressing force, which shouio compress equally 4.Take on pressure according to sharp sealing direction
| leakage of both ends
||1.Both sides fo sealing washer invalid
2.Trbing flabge clamp unepually or not clamp tlghtly3.Upper, lowar seaking washer invalln
|1.Exchange sealing washer
2.Conpress flange bolt tightly (compress equally)
3.Unload compressing ring, exchange invalid washer or gasket