If you want to know how to install butterfly valve,butterfly valve operation and maintenance and know the butterfly valve installation direction, this butterfly valve operation and maintenance manual will be a good butterfly valve installation guidelines.
1. Butterfly valve structure
2. Butterfly valve part material
No |
Name |
Materials |
Spare Parts |
1 |
BODY |
A126 Cl. B |
|
A536 Gr. 65-45-12 |
2 |
DISC |
A536 Gr. 65-45-12 |
|
A351 Gr. CF8 |
A351 Gr. CF8M |
3 |
O-RING |
NITRILE(NBR) |
|
4 |
DISC EDGE |
A182 Gr. F316 |
|
5 |
SEAT |
NITRILE(NBR) |
* |
EPDM |
NNEOPRENE(CR) |
VITON |
6 |
RETAINER |
A536 Gr. 65-45-12 |
|
7 |
BUSHING |
B62 |
|
8 |
BUSHING |
B62 |
|
9 |
UP_STEM |
A182 Gr. F6a |
|
A182 Gr. F304 |
10 |
DOWN_STEM |
A182 Gr. F6a |
|
A182 Gr. F304 |
11 |
THRUST RING |
B62 |
|
12 |
GLAND |
B62 |
|
13 |
BOTTOM COVER |
A126 Gr. B |
|
14 |
O-RING |
NITRILE(NBR) |
* |
15 |
GLAND PACKING |
NITRILE(NBR) |
* |
16 |
O-RING |
NITRILE(NBR) |
|
17 |
O-RING |
NITRILE(NBR) |
|
18 |
YOKE |
A536 Gr. 65-45-12 |
|
19 |
KEY |
A29 Gr. 1045 |
|
20 |
PIN |
A182 Gr. F316 |
|
21 |
PLUG |
A193 Gr. B8M |
|
22 |
BOLT |
A193 Gr. B8 |
|
23 |
SPRING WASHER |
A307 Gr. B |
|
24 |
BOLT |
A307 Gr. B |
|
25 |
BOLT |
A307 Gr. B |
|
26 |
SPRING WASHER |
A307 Gr. B |
|
27 |
SPRING WASHER |
A240 Gr. 304 |
|
28 |
STUD |
A193 Gr. B8 |
|
29 |
NUT |
A194 Gr. 8 |
|
30 |
NUT |
A307 Gr. B |
|
3. Butterfly valve maintenance
If the butterfly valve is left with the butterfly valve disc fully closed for a long time, the seat may be hardened. This would damage the seat and also cause the valve malfunction, etc. Open and close the valve once a month.
In order to use a butterfly valve for a long period, it is necessary to check and replace the major parts periodically (1 - 2 years). The repair parts have to be always stored in the warehouse or procured ahead of time.
1). Butterfly repair parts
Following are the repair parts for ordinary replacement.
Parts Name |
No. |
Quantity |
Gland Packing |
15 |
O-ring 4 pcs |
Bottom Gasket |
14 |
O-ring 1 pc |
Seat Ring |
5 |
Rubber 1 pc |
Note: In case of replacing the gland packing, replace all the gland packing, not only the damaged packing.
2). Butterfly valve replacement procedure for repair parts
2.1) The replacement procedure for the seat is as follows.
A. Disassembling
Before disassembling the valve, check the open / close indication on the actuator and confirm that the valve is at the closed position. If the valve is not in the closed position, operate the actuator to fully close the valve.
a. Remove the valve from the pipeline.
b. Place the valve horizontally on the wooden pieces in order not to damage the valve and with the seat retainer facing up.
c. If the rust or foreign matters are attached around the valve seat (valve seat and valve disc), remove with waste cloth or air blow. It should be taken not to damage the valve seat and disc edge.
d. Loosen and remove all the bolts and nuts fixing the seat retainer (hexagon socket screw) using a hexagonal spanner.
e. Remove the seat retainer bolt described above to disassemble the seat
retainer and the seat. If the seat and the disc got stuck and they are difficult to remove, operate the actuator to move the valve disc by 5˚ in the direction of "open". The seat retainer and the seat will be easily
removed. It is a good idea if you put a match mark before taking out the seat retainer from the seat body. Assembly would be much easier.
B. Attachment of the seat
Before attaching a new seat, confirm again that the rust and foreign particles are not attached around the valve seat. Attachment of rust and foreign particles may damage the seat. Remove them with a waste cloth or an air blow.
a. First, confirm that the valve disc of the valve is in the fully closed position. If not, operate the actuator so that the valve disc comes to the fully closed position.
b. Insert the seat to the seat-mounting groove. The seat is somewhat floating because there is an interference of the seat.
c. Insert the seat retainer to the mounting groove for the seat retainer. Due to the same reason as b, the seat and the seat retainer is somewhat floating.
d. Match the hole for the seat retainer and the tapped hole made on the valve body, and tighten slightly the seat retainer bolt (hexagon socket screw) using a hexagonal spanner.
e. After having tightened slightly the bolt above, operate the actuator so that the valve disc is opened by 10˚ in the "open" direction (the sealing position of the valve disc has come apart from the seat) and tighten up
the seat retainer bolt. Tighten the bolt to the extent that a part of the seat retainer does not come out of the surface of the valve body.
Note: Bolt Tightening Sequence
f. Operate the actuator again to bring the disc to the fully closed position before mounting to the piping.
2.2) Observe the following procedure for the replacement of the gland packing
A. Disassembling
First, loosen the bolts fixed the actuator and the body then remove the actuator. If the actuator is too heavy to carry, use a chain block.
a. Remove the gland bush
If it is difficult to remove, lift up the gland bush slightly using a driver and then pull out the gland bush from the valve stem. However, since the structure of the gland part varies depending on the valve models, please refer to the "Assembly drawing" as for the details.
b. In case the gland packing is made of rubber, after having pulled out the gland bush, remove the packing using a packing hook (packing puller). Always remove all the packing. When removing the packing, care should be taken so as not to damage the surface of valve shaft and stuffing box where the packing are attached.
c. Clean the stuffing box and the valve shaft with waste cloth.
B. Fitting Procedure
a. In case of synthetic rubber, insert the o-ring with silicone oil in the stuffing box of the valve body.
b. In case the gland packing is made of Teflon. Insert the packing from the top of the valve shaft one by one. Since the gland packing made of Teflon is a V-shape molded product, insert from the top of the valve shaft one by one. Apply grease for Teflon in order not to damage the gland packing.
Note: 1. Push the gland bush each time the gland packing is inserted into the stuffing box.
2). Always replace all the gland packing.
3). Insertion of the gland packing is; first place the adaptor and then V-shaped packing one by one as shown in the figure.
4. Butterfly valve troubles and countermeasures
Troubles |
Causes |
Countermeasures |
Leak from the seat |
The fully closed position of the seat is not correct |
Adjust the fully closed position of the stopper (in case of the electric motor type, re-adjust the position
limit) |
A foreign particle is caught
in the seat. |
Check inside of the valve and
remove the foreign particle. |
The seat is worn out or
damage |
Replacement of the seat. |
Leak from the gland |
The gland packing set was
loose. |
Re-tighten the gland bolts. |
The gland packing is worn
out or damaged. |
Replace the gland packing set. |
Leak from the
bottom cover. |
Bottom cover gasket is
worn out or damaged. |
Replace the bottom cover gasket. |
Leak from the gasket of the
flange |
The gasket is worn out or damaged. |
Replace the gasket |
Operation is not smooth |
A foreign particle is attached or caught in the
seat |
Disassemble the seat to check and remove the foreign particle. |
Note: As to the troubles other than mentioned above, please contact us for overhaul, etc.