butterfly valve

The operating torque of the triple eccentric butterfly valve is calculated based on normal temperature and cleaning medium. For high temperature, low temperature conditions and non-clean media, it will lead to an increase in the operating torque of the triple eccentric butterfly valve.

butterfly valve

During the opening and closing process of the three eccentric butterfly valve, the required opening and closing force and opening and closing torque are varied, and the maximum value is the initial moment of closing or the initial moment of opening. There are special requirements for the speed of the opening and closing process for some special working conditions.

We should know the actual operation torque to choose correct pneumatic or electric actuator. The correct choose of actuator could open the valve in time during operation.

 

1. The torque calculation of the triple eccentric butterfly valves is as follows:

(1)Valve Plate Area: S

Nominal diameter: D

S = (Dx1/2)2×3.14

(2)Static pressure on the shaft: P1

Nominal pressure: P

P1 = S x P

(3)Torque of triple eccentric butterfly valves: T , unit: N.M.

Friction coefficient: K (The friction coefficient of steel is 0.1, and the friction coefficient of steel to rubber is 0.15.)

Shaft diameter: d

T = P1 x K x d x 1/1000

(4)Electric actuator and pneumatic actuator normally apply the safety torque value according to 1.5 time of triple eccentric butterfly valve’s torque

2. Triple eccentric butterfly valve torque values are as follows:

Size Nominal Pressure
DN NPS 0.6MPa 1.0MPa 1.6MPa 2.5MPa 4.0MPa 6.3MPa 285PSI 740PSI 1480PSI
50 2″ 37
65 21/2″ 29 35 60 82 106 142 69 123 213
80 3″ 34 57 81 102 148 290 174 271 460
100 4″ 61 102 141 180 259 526 250 395 834
125 5″ 104 165 228 289 412 641 283 548 979
150 6″ 178 250 450 564 790 1060 473 825 2938
200 8″ 201 400 601 800 1201 1567 674 1503 3616
250 10″ 353 518 956 1250 1860 2697 983 1887 5649
300 12″ 635 992 1352 1711 2428 3147 2022 2508 11863
350 14″ 819 1623 2234 2844 4067 4855 2520 4158 14123
400 16″ 1047 1944 2842 3738 5533 6473 3175 6271 17061
450 18″ 1451 2451 3452 4412 6454 4239 7864 21015
500 20″ 2043 3285 4527 5769 8253 5531 10361 26551
600 24″ 2779 5548 6018 9495 13443 6011 17559 38415
700 28″ 6890
750 30″ 3230 6723 7700 16552 12654 33105
800 32″ 8760 52877
900 36″ 5275 8474 9750 26438 18078
1000 40″ 6915 11717 13560 24179 80219
1050 42″ 8135 15253 16270 40110 34000 24857
1200 48″ 12540 20563 22360 38900 41900 36155
1350 54″ 18300 21806 29977
1400 56″ 24650 34900
1500 60″ 36440 36155 43397
1600 64″ 40850 48600
1800 72″
2000 80″
2200 88″
2400 96″
2600 104″
2800 112″
3000 120″