TBNⅡ Series Rack and Pinion Pneumatic Actuator
1、Extruded aluminium body, with both internal and external hard anodized corrosion protection having honed cylinder surface for longer life and lower coefficient of friction.
2、Dual piston rack and pinion design for compact construction,symmetric mounting position, high cycle life and fast operation,reverse rotation can be accomplished in the field by simply inverting the pistons.
3、One-piece gear output shaft,with nickel plated,long service life.And can be customized size and stainless steel material as option.
4、Die-cast aluminum alloy end caps,epoxy coated with high anti-corrosion performance.Can be customized various colors or PTFE coating.
5、Two indipendent external travel stop adjustments. Permits an easy and precise adjustment of +/-5°in both directions,in the open and close positions for an accurate valve alignment.
6、Selected high quality bearings and seal for low friction, high cycle life and a wide operating temperature range.
7、Modular preloaded spring cartridge design. With coated spring for simple versatile range,greater safety and corrosion resistance.
8、Internal and external stainless steel fasteners for long term corrosion resistance.
9、ISO 5211, DIN 3337 and 和VDI/VDE 3845 NAMUR:Full conformance to the latest specifications:ISO 5211,DIN 3337 and VDI/VDE 3845 NAMUR for product interchangeability and easy mounting of solenoids,limit switches and other accessories.
NO. | Description | Qty | Material | |
1 | Body | 1 | Aluminium Alloy | Anodized Oxygenation |
2 | Pinion | 1 | Alloy Steel | Nickel Plated |
3 | Bearing(Lower Pinion) | 1 | POM | |
4 | O-Ring(Lower Pinion) | 1 | NBR | |
5 | O-Ring(Top Pinion) | 1 | NBR | |
6 | Bearing(Top Pinion) | 1 | POM | |
7 | Spacer | 1 | Alloy Steel | |
8 | Thrust Bearing Pinion | 1 | POM | |
9 | Thrust Bearing Pinion | 1 | POM | |
10 | Thrust Washer(Pinion) | 1 | Stainless Steel | |
11 | Spring Clip | 1 | Stainless Steel | |
12 | Piston | 2 | Alloy Steel | Hard Anodized |
13 | Guide Ring(Piston) | 2 | POM | |
14 | O-Ring(Piston) | 2 | NBR | |
15 | BearingRing(Piston) | 2 | POM | |
16 | Adjusting Screw | 2 | Stainless Steel | |
17 | Adjusting Nut | 2 | Stainless Steel | |
18 | Washer(Adjusting Screw) | 2 | Stainless Steel | |
19 | O-Ring(Adjusting Screw) | 2 | NBR | |
20 | Plug | 2 | NBR | |
21 | Spring | 4~12 | Spring steel | Zinc Phosphate Coated |
22 | End Cap | 2 | Alloy Steel | Epoxy Coated |
23 | Adjusting Screw(End Cap) | 2 | Stainless Steel | |
24 | Adjusting Nut(End Cap) | 2 | Stainless Steel | |
25 | O-Ring(End Cap) | 2 | NBR | |
26 | Bolts(End Cap) | 8 | Stainless Steel | |
27 | Indicator | 1 | Engineering Plastics | |
28 | Nut(Indicator) | 1 | Engineering Plastics |
Model | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | Air |
TBNII032 | 111 | 46 | 52 | 66 | 21 | 31 | 14 | 50 | 25 | / | F03Ф36 | / | M5X8 | 9 | 40 | G1/8 |
TBNII052 | 154 | 74 | 45 | 99 | 30 | 47 | 14 | 80 | 30 | F05Ф50 | F03Ф36 | M6X11 | M5X10 | 11 | 40 | G1/4 |
TBNII063 | 173 | 88 | 50 | 113 | 36 | 54 | 18 | 80 | 30 | F07Ф70 | F05Ф50 | M8X14 | M6X11 | 14 | 40 | G1/4 |
TBNII075 | 190 | 100 | 55 | 125 | 42 | 60 | 20 | 80 | 30 | F07Ф70 | F05Ф50 | M8X14 | M6X11 | 14 | 40 | G1/4 |
TBNII083 | 208 | 109 | 60 | 134 | 46 | 65 | 20 | 80 | 30 | F07Ф70 | F05Ф50 | M8X14 | M6X11 | 17 | 40 | G1/4 |
TBNII092 | 254 | 120 | 70 | 145 | 51 | 70 | 22 | 80 | 30 | F07Ф70 | F05Ф50 | M8X14 | M6X11 | 17 | 40 | G1/4 |
TBNII105 | 282 | 135 | 70 | 160 | 58 | 76 | 24 | 80 | 30 | F10Ф102 | F07Ф70 | M10X18 | M8X14 | 22 | 40 | G1/4 |
TBNII125 | 312 | 155 | 80 | 182 | 68 | 87 | 28 | 80 | 30 | F10Ф102 | F07Ф70 | M10X18 | M8X14 | 22 | 65 | G1/4 |
TBNII140 | 380 | 178 | 95 | 205 | 76 | 96 | 32 | 80 | 30 | F12Ф125 | F10Ф102 | M12X22 | M10X18 | 27 | 65 | G1/4 |
TBNII160 | 426 | 197 | 100 | 224 | 87 | 107 | 34 | 80 | 30 | F12Ф125 | F10Ф102 | M12X22 | M10X18 | 27 | 65 | G1/4 |
TBNII190 | 484 | 235 | 125 | 275 | 103 | 126 | 40 | 130 | 30 | F14Ф140 | / | M16X23 | / | 36 | 78 | G1/4 |
TBNII210 | 532 | 260 | 130 | 300 | 113 | 137 | 40 | 130 | 30 | F14Ф140 | / | M16X25 | / | 36 | 78 | G1/4 |
TBNII240 | 610 | 292 | 145 | 330 | 146 | 158 | 50 | 130 | 30 | F16Ф165 | / | M20X28 | / | 46 | 78 | G1/2(1/4) |
TBNII270 | 704 | 330 | 170 | 370 | 165 | 175 | 57 | 130 | 30 | F16Ф165 | / | M20X28 | / | 46 | 78 | G1/2 |
TBNII300 | 782 | 352 | 308 | 385 | 160 | 170 | 50 | 130 | 30 | F16Ф165 | / | M20X25 | / | 46 | 80 | G1/2 |
TBNII350 | 920 | 410 | 362 | 440 | 190 | 195 | 50 | 130 | 30 | F25Ф254 | F16Ф165 | M16X24 | M20X25 | 55 | 80 | G1/2 |
TBNII400 | 935 | 460 | 446 | 494 | 260 | 260 | 60 | 130 | 30 | F25Ф254 | F16Ф165 | M16X24 | M20X25 | 55 | 80 | G1/2 |
Output Torque of Air Supply(bar) | Output Torque of Spring | ||||||||||||
Air pressure | 3 | 4 | 5 | 6 | 7 | ||||||||
Model | spring quantity | 0° | 90° | 0° | 90° | 0° | 90° | 0° | 90° | 0° | 90° | 0° | 90° |
Origin | End | Origin | End | Origin | End | Origin | End | Origin | End | Origin | End | ||
TBNII052S | 5 | 8.2 | 5.6 | 12.1 | 9.4 | 3.7 | 6.0 | ||||||
6 | 7.4 | 4.4 | 11.4 | 8.2 | 4.4 | 7.1 | |||||||
7 | 6.7 | 3.2 | 10.6 | 7.0 | 5.2 | 8.3 | |||||||
8 | 9.9 | 5.9 | 13.9 | 9.7 | 5.9 | 9.5 | |||||||
9 | 9.2 | 4.7 | 13.1 | 8.5 | 6.6 | 10.7 | |||||||
10 | 8.4 | 3.5 | 12.4 | 7.3 | 16.3 | 11.2 | 7.4 | 11.9 | |||||
11 | 11.6 | 6.1 | 15.6 | 10.0 | 19.6 | 13.8 | 8.1 | 13.1 | |||||
12 | 10.9 | 4.9 | 14.9 | 8.8 | 18.8 | 12.6 | 8.9 | 14.3 | |||||
TBNII063S | 5 | 14.2 | 9.9 | 21.2 | 16.7 | 6.7 | 10.5 | ||||||
6 | 12.9 | 7.8 | 19.9 | 14.6 | 8.1 | 12.6 | |||||||
7 | 11.5 | 5.7 | 18.5 | 12.5 | 25.5 | 19.3 | 9.4 | 14.7 | |||||
8 | 17.2 | 10.4 | 24.1 | 17.2 | 31.1 | 23.9 | 10.8 | 16.8 | |||||
9 | 15.8 | 8.3 | 22.8 | 15.1 | 29.8 | 21.9 | 12.1 | 18.9 | |||||
10 | 14.5 | 6.2 | 21.5 | 13.0 | 28.4 | 19.8 | 35.4 | 26.5 | 13.4 | 21.0 | |||
11 | 13.1 | 4.1 | 20.1 | 10.9 | 27.1 | 17.7 | 34.1 | 24.4 | 14.8 | 23.1 | |||
12 | 18.8 | 8.8 | 25.7 | 15.6 | 32.7 | 22.3 | 16.1 | 25.2 | |||||
TBNII075S | 5 | 19.3 | 14.6 | 29.2 | 24.2 | 10.3 | 14.2 | ||||||
6 | 17.2 | 11.8 | 27.1 | 21.4 | 12.4 | 17.0 | |||||||
7 | 15.2 | 8.9 | 25.0 | 18.5 | 14.4 | 19.9 | |||||||
8 | 23.0 | 15.7 | 32.8 | 25.3 | 16.5 | 22.7 | |||||||
9 | 20.9 | 12.8 | 30.8 | 22.4 | 18.5 | 25.5 | |||||||
10 | 18.9 | 10.0 | 28.7 | 19.6 | 38.6 | 29.2 | 20.6 | 28.4 | |||||
11 | 26.7 | 16.8 | 36.5 | 26.4 | 46.4 | 36.0 | 22.7 | 31.2 | |||||
12 | 24.6 | 13.9 | 34.5 | 23.5 | 44.3 | 33.1 | 24.7 | 34.1 | |||||
TBNII083S | 5 | 27.9 | 20.4 | 42.0 | 34.1 | 14.4 | 20.8 | ||||||
6 | 25.0 | 16.2 | 39.2 | 30.0 | 17.3 | 25.0 | |||||||
7 | 22.1 | 12.1 | 36.3 | 25.8 | 20.2 | 29.1 | |||||||
8 | 33.4 | 21.6 | 47.5 | 35.4 | 23.1 | 33.3 | |||||||
9 | 30.5 | 17.5 | 44.6 | 31.2 | 26.0 | 37.4 | |||||||
10 | 27.6 | 13.3 | 41.7 | 27.1 | 55.9 | 40.8 | 28.9 | 41.6 | |||||
11 | 38.8 | 22.9 | 53.0 | 36.6 | 67.1 | 50.4 | 31.8 | 45.7 | |||||
12 | 36.0 | 18.7 | 50.1 | 32.5 | 64.2 | 46.2 | 34.7 | 49.9 | |||||
TBNII092S | 5 | 45.1 | 32.9 | 67.4 | 54.6 | 22.0 | 32.3 | ||||||
6 | 40.7 | 26.4 | 63.0 | 48.2 | 26.4 | 38.8 | |||||||
7 | 36.3 | 20.0 | 58.6 | 41.7 | 30.8 | 45.2 | |||||||
8 | 54.2 | 35.2 | 76.6 | 57.0 | 35.2 | 51.7 | |||||||
9 | 49.8 | 28.8 | 72.2 | 50.5 | 29.6 | 58.2 | |||||||
10 | 45.4 | 22.3 | 67.8 | 44.1 | 90.1 | 65.8 | 44.0 | 64.6 | |||||
11 | 63.4 | 37.6 | 85.7 | 59.3 | 108.1 | 81.1 | 48.4 | 71.1 | |||||
12 | 59.0 | 31.1 | 81.3 | 52.9 | 103.7 | 74.6 | 52.8 | 77.6 | |||||
TBNII105S | 5 | 64.9 | 47.0 | 97.3 | 78.5 | 32.2 | 47.4 | ||||||
6 | 58.5 | 37.5 | 90.9 | 69.0 | 38.6 | 56.9 | |||||||
7 | 52.1 | 28.0 | 84.4 | 59.5 | 45.1 | 66.4 | |||||||
8 | 78.0 | 50.0 | 110.4 | 81.5 | 51.5 | 75.9 | |||||||
9 | 71.6 | 40.5 | 103.9 | 72.0 | 57.9 | 85.4 | |||||||
10 | 65.1 | 31.0 | 97.5 | 62.5 | 129.9 | 94.0 | 64.4 | 94.8 | |||||
11 | 91.0 | 53.0 | 123.4 | 84.5 | 155.9 | 116.0 | 70.8 | 104.3 | |||||
12 | 84.6 | 43.5 | 117.0 | 75.0 | 149.4 | 106.5 | 77.3 | 113.8 |
Output Torque of Air Supply(bar) | Output Torque of Spring | ||||||||||||
Air pressure | 3 | 4 | 5 | 6 | 7 | ||||||||
Model | spring quantity | 0° | 90° | 0° | 90° | 0° | 90° | 0° | 90° | 0° | 90° | 0° | 90° |
Origin | End | Origin | End | Origin | End | Origin | End | Origin | End | Origin | End | ||
TBNII125S | 5 | 100.1 | 74.8 | 150.5 | 123.9 | 51.3 | 72.3 | ||||||
6 | 89.8 | 60.4 | 140.3 | 109.4 | 61.6 | 86.8 | |||||||
7 | 79.5 | 45.9 | 130.0 | 94.9 | 71.9 | 101.2 | |||||||
8 | 119.7 | 80.5 | 170.2 | 129.5 | 82.1 | 115.7 | |||||||
9 | 109.5 | 66.0 | 159.9 | 115.1 | 92.4 | 130.1 | |||||||
10 | 99.2 | 51.6 | 149.7 | 100.6 | 200.2 | 149.6 | 102.6 | 144.6 | |||||
11 | 139.4 | 86.1 | 189.9 | 135.2 | 240.4 | 184.2 | 112.9 | 159.1 | |||||
12 | 129.2 | 71.7 | 179.6 | 120.7 | 230.1 | 169.8 | 123.2 | 173.5 | |||||
TBNII140S | 5 | 158.1 | 116.4 | 237.3 | 193.4 | 79.3 | 114.8 | ||||||
6 | 142.3 | 93.4 | 221.4 | 170.5 | 95.2 | 137.8 | |||||||
7 | 126.4 | 70.4 | 205.6 | 147.5 | 111.1 | 160.7 | |||||||
8 | 189.7 | 124.5 | 268.8 | 201.6 | 126.9 | 183.7 | |||||||
9 | 173.8 | 101.6 | 253 | 178.6 | 142.8 | 206.7 | |||||||
10 | 158.0 | 78.6 | 237.1 | 155.7 | 316.3 | 232.7 | 158.7 | 229.6 | |||||
11 | 221.2 | 132.7 | 300.4 | 209.8 | 379.6 | 286.8 | 174.5 | 252.6 | |||||
12 | 205.4 | 109.8 | 284.5 | 186.8 | 363.7 | 263.9 | 190.4 | 275.5 | |||||
TBNII160S | 5 | 225.1 | 165.6 | 337.9 | 275.4 | 113.3 | 163.6 | ||||||
6 | 202.4 | 132.9 | 315.2 | 242.7 | 135.9 | 196.4 | |||||||
7 | 179.8 | 100.2 | 292.6 | 209.9 | 158.6 | 229.1 | |||||||
8 | 269.9 | 177.2 | 382.7 | 287.0 | 181.2 | 261.8 | |||||||
9 | 247.2 | 144.5 | 360.0 | 254.2 | 203.9 | 294.6 | |||||||
10 | 224.7 | 111.7 | 337.4 | 221.5 | 450.2 | 331.3 | 226.5 | 327.3 | |||||
11 | 314.7 | 188.8 | 427.5 | 298.5 | 540.3 | 408.3 | 249.2 | 360.0 | |||||
12 | 292.1 | 156 | 404.9 | 265.8 | 517.6 | 375.6 | 271.8 | 392.7 | |||||
TBNII190S | 5 | 356.4 | 267.1 | 536.6 | 442.7 | 184.3 | 259.6 | ||||||
6 | 319.5 | 215.2 | 499.8 | 390.8 | 221.2 | 311.5 | |||||||
7 | 282.7 | 163.3 | 462.9 | 338.9 | 258.1 | 363.4 | |||||||
8 | 426.0 | 287.0 | 606.3 | 462.5 | 295.0 | 415.3 | |||||||
9 | 389.2 | 235.0 | 569.4 | 410.6 | 331.8 | 467.3 | |||||||
10 | 352.3 | 183.1 | 532.5 | 358.7 | 712.8 | 534.3 | 368.7 | 519.2 | |||||
11 | 495.7 | 306.8 | 675.9 | 482.3 | 856.2 | 657.9 | 405.6 | 571.1 | |||||
12 | 458.8 | 254.9 | 639.0 | 430.4 | 819.3 | 606.0 | 442.4 | 623.0 | |||||
TBNII210S | 5 | 514.1 | 388.8 | 773.2 | 641.5 | 263.0 | 369.2 | ||||||
6 | 461.5 | 315.0 | 720.6 | 567.6 | 315.6 | 443.0 | |||||||
7 | 408.9 | 241.1 | 668.0 | 493.8 | 368.2 | 516.9 | |||||||
8 | 615.4 | 420.0 | 874.4 | 672.6 | 420.8 | 590.7 | |||||||
9 | 562.8 | 346.1 | 821.8 | 598.8 | 473.4 | 664.6 | |||||||
10 | 510.2 | 272.3 | 769.2 | 524.9 | 1028.3 | 777.6 | 526.0 | 738.4 | |||||
11 | 716.6 | 451.1 | 975.7 | 703.8 | 1234.7 | 956.4 | 578.6 | 812.2 | |||||
12 | 664.0 | 377.3 | 923.1 | 629.9 | 1182.1 | 882.6 | 631.2 | 886.1 | |||||
TBNII240S | 5 | 746 | 572 | 1126 | 944 | 396 | 542 | ||||||
6 | 667 | 464 | 1047 | 835 | 475 | 651 | |||||||
7 | 587 | 355 | 968 | 727 | 555 | 759 | |||||||
8 | 889 | 618 | 1269 | 990 | 634 | 867 | |||||||
9 | 809 | 510 | 1190 | 881 | 713 | 976 | |||||||
10 | 730 | 402 | 1111 | 773 | 1492 | 1144 | 792 | 1084 | |||||
11 | 1032 | 665 | 1412 | 1036 | 1793 | 1407 | 872 | 1193 | |||||
12 | 952 | 556 | 1333 | 928 | 1714 | 1299 | 951 | 1301 | |||||
TBNII270S | 5 | 1156 | 852 | 1734 | 1416 | 578 | 842 | ||||||
6 | 1041 | 683 | 1619 | 1248 | 694 | 1011 | |||||||
7 | 925 | 515 | 1503 | 1079 | 809 | 1179 | |||||||
8 | 1388 | 911 | 1966 | 1476 | 925 | 1348 | |||||||
9 | 1272 | 742 | 1850 | 1307 | 1040 | 1516 | |||||||
10 | 1157 | 574 | 1735 | 1139 | 2313 | 1703 | 1156 | 1685 | |||||
11 | 1619 | 970 | 2197 | 1535 | 2775 | 2099 | 1272 | 1853 | |||||
12 | 1503 | 802 | 2082 | 1366 | 2660 | 1931 | 1387 | 2022 | |||||
TBNII300S | 6 | 1316 | 875 | 876 | 1273 | ||||||||
7 | 1153 | 639 | 1916 | 1402 | 1022 | 1485 | |||||||
8 | 991 | 403 | 1754 | 1166 | 2517 | 1929 | 1168 | 1697 | |||||
9 | 1592 | 930 | 2355 | 1693 | 3118 | 2456 | 1314 | 1909 | |||||
10 | 1430 | 695 | 2193 | 1458 | 2956 | 2221 | 3719 | 2984 | 1460 | 2122 | |||
11 | 2030 | 1222 | 2793 | 1985 | 3556 | 2748 | 1606 | 2334 | |||||
12 | 1868 | 986 | 2631 | 1749 | 3394 | 2512 | 1752 | 2546 | |||||
TBNII350S | 6 | 1863 | 1157 | 1408 | 2043 | ||||||||
7 | 1602 | 779 | 2745 | 1922 | 1642 | 2383 | |||||||
8 | 1341 | 401 | 2484 | 1544 | 3626 | 2686 | 1877 | 2724 | |||||
9 | 2224 | 1165 | 3336 | 2307 | 4508 | 3449 | 2112 | 3064 | |||||
10 | 1963 | 787 | 3105 | 1929 | 4247 | 3071 | 5390 | 4214 | 2346 | 3405 | |||
11 | 2844 | 1551 | 3986 | 2693 | 5129 | 3836 | 2581 | 3745 | |||||
12 | 2584 | 1172 | 3726 | 2314 | 4869 | 3457 | 2816 | 4086 | |||||
TBNII400S | 8 | 2550 | 1225 | 2100 | 3292 | ||||||||
9 | 2259 | 768 | 3887 | 2396 | 2362 | 3703 | |||||||
10 | 1967 | 311 | 3595 | 1939 | 5223 | 3567 | 2624 | 4115 | |||||
11 | 3303 | 1482 | 4931 | 3110 | 6559 | 4738 | 7895 | 5908 | 2887 | 4526 | |||
12 | 3012 | 1025 | 4640 | 2653 | 6268 | 4281 | 7603 | 5450 | 3149 | 4938 | |||
13 | 4348 | 2195 | 5976 | 3823 | 7312 | 4993 | 3412 | 5349 | |||||
14 | 4057 | 1738 | 5685 | 3366 | 7020 | 4536 | 3674 | 5761 | |||||
15 | 3765 | 1281 | 5393 | 2909 | 6728 | 4079 | 3937 | 6172 | |||||
16 | 5101 | 2452 | 4199 | 6584 |
Model | Air Pressure(Bar) | ||||||
2 | 3 | 4 | 5 | 6 | 7 | 8 | |
TBNII032D | 2.7 | 4.2 | 5.8 | 7.4 | 9 | 10.5 | 11.8 |
TBNII052D | 7.9 | 11.9 | 15.9 | 19.9 | 23.8 | 27.8 | 31.7 |
TBNII063D | 14 | 21 | 28 | 35 | 42 | 49 | 55.9 |
TBNII075D | 19.8 | 29.7 | 39.6 | 49.5 | 59.4 | 69.2 | 79.1 |
TBNII083D | 28.3 | 42.5 | 56.6 | 70.7 | 84.9 | 99 | 113.2 |
TBNII092D | 44.7 | 67.1 | 89.5 | 118.9 | 134.2 | 156.6 | 179 |
TBNII105D | 64.8 | 97.1 | 129.5 | 161.9 | 194.3 | 226.7 | 259 |
TBNII125D | 101 | 151.4 | 201.9 | 252.4 | 302.9 | 353.4 | 403.8 |
TBNII140D | 158.3 | 237.5 | 316.6 | 395.8 | 474.9 | 554.1 | 633.2 |
TBNII160D | 225 | 338 | 451 | 564 | 677 | 790 | 902 |
TBNII190D | 361 | 541 | 721 | 901 | 1082 | 1262 | 1442 |
TBNII210D | 518 | 777 | 1036 | 1295 | 1554 | 1813 | 2072 |
TBNII240D | 761 | 1142 | 1523 | 1903 | 2284 | 2665 | 3045 |
TBNII270D | 1156 | 1734 | 2312 | 2891 | 3469 | 4047 | 4625 |
TBNII300D | 1526 | 2289 | 3052 | 3815 | 4578 | 5341 | 6104 |
TBNII350D | 2285 | 3427 | 4570 | 5712 | 6854 | 7997 | 9139 |
TBNII400D | 3256 | 4884 | 6512 | 8140 | 9768 | 11396 | 13024 |
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- 1. Air from Port A forces the pistons outwards,causing the springs to compress, the pinion turns counter-clockwise to open the valve while air is being exhausted from Port B.
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- 2. Air from Port B forces the pistons inwards causing the springs to compress, the pinion turns clockwise to close the valve while air is being exhausted from Port A.
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- 1. Air from Port Aforces the pistons outwards causing the springs to compress, the pinion turns counter-clockwise to open the vaive while air is being exhausted from Port B.
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- 2. In case of air or power disruption, the rebound of springs forces the pistons inwards, the pinion turns clockwise to close the vaive while air is being exhausted from Port A. Air from Port B can accelerate the close of the vaive.
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- 1. Air from Port A forces the pistons outwards causing the springs to compress, the pinion turns clockwise to close the valve while air is being exhausted from Port B.
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- 2. In case of air or power disruption,the rebound of springs forces the pistons inwards,the pinion turns counter-clockwise to open the vaive while air is being exhausted from Port A.Air from Port B can accelerate the open of the vaive.