Data Sheet 75: Working with SI (System International) Cylinders – Part 2
Piston Velocity – Metric Hydraulic Cylinders – For Pump Flows of 3 to 75 Liters per Minute
Piston Diameter mm. | Rod Diameter mm. | 3 l/min. | 5 l/min. | 10 l/min. | 15 l/min. | 20 l/min | 25 l/min. | 30 l/min. | 40 l/min. | 50 l/min. | 75 l/min. |
25 | None* | 6.111 | 10.19 | 20.37 | – – – – | – – – – | – – – – | – – – – | – – – – | – – – – | – – – – |
12 | 7.938 | 13.23 | 26.46 | – – – – | – – – – | – – – – | – – – – | – – – – | – – – – | – – – – | |
18 | 12.68 | 21.14 | 42.27 | – – – – | – – – – | – – – – | – – – – | – – – – | – – – – | – – – – | |
32 | None* | 3.732 | 6.220 | 12.44 | 18.66 | Figures in the body of this chart are piston speeds in meters per minute (m/min). | – – – – | ||||
14 | 4.614 | 7.690 | 15.38 | 23.07 | – – – – | ||||||
22 | 7.077 | 11.80 | 23.59 | 35.39 | – – – – | – – – – | – – – – | – – – – | – – – – | – – – – | |
40 | None* | 2.387 | 3.978 | 7.955 | 11.93 | 15.91 | 19.89 | – – – – | – – – – | – – – – | – – – – |
18 | 2.992 | 4.987 | 9.974 | 14.96 | 19.95 | 24.94 | – – – – | – – – – | – – – – | – – – – | |
28 | 4.677 | 7.795 | 15.59 | 23.39 | 31.18 | 38.98 | – – – – | – – – – | – – – – | – – – – | |
50 | None* | 1.528 | 2.547 | 5.094 | 7.641 | 10.19 | 12.74 | 15.28 | 20.39 | – – – – | – – – – |
22 | 1.895 | 3.159 | 6.316 | 9.476 | 12.63 | 15.79 | 18.95 | 25.28 | – – – – | – – – – | |
36 | 3.174 | 5.290 | 10.58 | 15.87 | 21.16 | 26.45 | 31.74 | 42.34 | – – – – | – – – – | |
63 | None* | 0.9624 | 1.604 | 3.208 | 4.812 | 6.415 | 8.020 | 9.624 | 12.84 | 16.03 | – – – – |
28 | 1.199 | 1.999 | 3.998 | 5.997 | 7.995 | 9.995 | 11.99 | 15.00 | 19.82 | – – – – | |
45 | 1.965 | 3.275 | 6.550 | 9.824 | 13.10 | 16.37 | 19.65 | 26.21 | 32.74 | – – – – | |
80 | None* | 0.5968 | 0.9947 | 1.989 | 2.984 | 3.978 | 4.973 | 5.968 | 7.961 | 9.943 | 14.82 |
36 | 0.7483 | 1.247 | 2.494 | 3.742 | 4.988 | 6.236 | 7.483 | 9.982 | 12.47 | 18.71 | |
56 | 1.170 | 1.950 | 3.900 | 5.850 | 7.800 | 9.751 | 11.70 | 15.61 | 19.49 | 29.25 | |
100 | None* | 0.3820 | 0.6366 | 1.273 | 1.910 | 2.546 | 3.183 | 3.820 | 5.095 | 6.364 | 9.549 |
45 | 0.4790 | 0.7983 | 1.597 | 2.395 | 3.193 | 3.991 | 4.790 | 6.389 | 7.979 | 11.97 | |
70 | 0.7490 | 1.248 | 2.497 | 3.745 | 4.993 | 6.241 | 7.490 | 9.991 | 12.49 | 18.72 | |
125 | None* | 0.2445 | 0.4074 | 0.8149 | 1.222 | 1.630 | 2.037 | 2.445 | 3.261 | 4.073 | 6.112 |
56 | 0.3060 | 0.5100 | 1.020 | 1.529 | 2.039 | 2.549 | 3.059 | 4.080 | 5.096 | 7.646 | |
90 | 0.5076 | 0.8460 | 1.692 | 2.538 | 3.384 | 4.230 | 5.076 | 6.771 | 8.457 | 12.69 | |
160 | None* | 0.1492 | 0.2487 | 0.4974 | 0.7460 | 0.9946 | 1.243 | 1.492 | 1.990 | 2.486 | 3.730 |
70 | 0.1845 | 0.3080 | 0.6151 | 0.9227 | 1.230 | 1.538 | 1.845 | 2.462 | 3.074 | 4.613 | |
110 | 0.2830 | 0.4716 | 0.9432 | 1.415 | 1.887 | 1.358 | 2.830 | 3.776 | 4.714 | 7.074 | |
200 | None* | 0.0955 | 0.1592 | 0.3183 | 0.4775 | 0.6366 | 0.7958 | 0.9549 | 1.284 | 1.591 | 2.387 |
90 | 0.1197 | 0.1996 | 0.3991 | 0.5987 | 0.7982 | 0.9978 | 1.197 | 1.597 | 1.995 | 2.994 | |
140 | 0.1872 | 0.3121 | 0.6241 | 0.9362 | 1.248 | 1.560 | 1.872 | 2.498 | 3.119 | 4.681 |
Piston Velocity – Metric Hydraulic Cylinders – For Pump Flows of 100 to 450 Liters per Minute
Piston Diameter mm. | Rod Diameter mm. | 100 l/min. | 125 l/min. | 150 l/min. | 175 l/min. | 200 l/min. | 250 l/min. | 300 l/min. | 350 l/min. | 400 l/min. | 450 l/min. |
Figures in the body of this chart are piston speeds in meters per minute (m/min.). | |||||||||||
80 | None* | 19.89 | 24.87 | – – – – | – – – – | – – – – | – – – – | – – – – | – – – – | – – – – | – – – – |
36 | 24.94 | 31.18 | – – – – | – – – – | – – – – | – – – – | – – – – | – – – – | – – – – | – – – – | |
56 | 39.00 | 48.75 | – – – – | – – – – | – – – – | – – – – | – – – – | – – – – | – – – – | – – – – | |
100 | None* | 12.73 | 15.92 | 19.10 | 22.28 | 25.46 | – – – – | – – – – | – – – – | – – – – | – – – – |
45 | 15.97 | 19.96 | 23.95 | 27.94 | 31.93 | – – – – | – – – – | – – – – | – – – – | – – – – | |
70 | 24.97 | 31.21 | 37.45 | 43.69 | 49.93 | – – – – | – – – – | – – – – | – – – – | – – – – | |
125 | None | 8.149 | 10.19 | 12.22 | 14.26 | 16.30 | 20.37 | 24.44 | 28.52 | – – – – | – – – – |
56 | 10.20 | 12.74 | 15.29 | 17.84 | 20.39 | 25.49 | 30.59 | 35.68 | – – – – | – – – – | |
90 | 16.92 | 21.15 | 25.38 | 29.61 | 33.84 | 42.30 | 50.76 | 59.22 | – – – – | – – – – | |
160 | None | 4.974 | 6.217 | 7.460 | 8.704 | 9.947 | 12.43 | 14.92 | 17.41 | 19.89 | 22.38 |
70 | 6.151 | 7.689 | 9.227 | 10.76 | 12.30 | 15.38 | 18.45 | 21.53 | 24.60 | 27.68 | |
110 | 9.432 | 11.79 | 14.15 | 16.51 | 18.86 | 23.58 | 28.29 | 33.01 | 37.73 | 42.44 | |
200 | None | 3.183 | 3.979 | 4.775 | 5.570 | 6.366 | 7.958 | 9.549 | 11.14 | 12.73 | 14.32 |
90 | 3.991 | 4.989 | 5.987 | 6.985 | 7.983 | 9.978 | 11.97 | 13.97 | 15.97 | 17.96 | |
140 | 6.241 | 7.802 | 9.362 | 10.92 | 12.48 | 15.60 | 18.72 | 21.84 | 24.97 | 28.09 |
U. S. AND METRIC SI PRESSURE AND FLOW CONVERSIONS
for Operation of Air and Hydraulic Cylinders
PRESSURE | HYDRAULIC FLOW | AIR FLOW | ||||||||||||||
PSI (lbs/sq. inch) and Bars | GPM and Liters per Minute | CFM and Cubic Decimeters per Sec | ||||||||||||||
1 PSI = 0.0689655 Bar | 1 GPM = 3.785 Liters per Minute | 1 CFM = 0.47195 dm³/sec | ||||||||||||||
1 Bar = 14.5 PSI | 1 Liter per Minute = 0.2642 GPM | 1 dm³/sec = 2.1187 CFM | ||||||||||||||
PSI | Bars | Bars | PSI | GPM | l/min | l/min | GPM | CFM | dm³/sec | dm³/sec | CFM | |||||
20 | 1.379 | 1 | 14.5 | 1 | 3.785 | 5 | 1.32 | 1 | 0.472 | 5 | 10.59 | |||||
30 | 2.069 | 2 | 29.0 | 2 | 7.570 | 10 | 2.64 | 2 | 0.944 | 10 | 21.19 | |||||
40 | 2.759 | 3 | 43.5 | 3 | 11.36 | 15 | 3.96 | 3 | 1.416 | 15 | 31.78 | |||||
50 | 3.448 | 4 | 58.0 | 4 | 15.14 | 20 | 5.28 | 4 | 1.888 | 20 | 42.37 | |||||
60 | 4.138 | 5 | 72.5 | 5 | 18.93 | 30 | 7.93 | 5 | 2.360 | 30 | 63.56 | |||||
70 | 4.828 | 6 | 87.0 | 10 | 37.85 | 40 | 10.6 | 10 | 4.720 | 40 | 84.75 | |||||
80 | 5.517 | 7 | 102 | 15 | 56.78 | 50 | 13.2 | 15 | 7.079 | 50 | 105.9 | |||||
90 | 6.207 | 8 | 116 | 20 | 75.70 | 75 | 19.8 | 20 | 9.439 | 75 | 158.9 | |||||
100 | 6.897 | 9 | 131 | 25 | 94.63 | 100 | 26.4 | 25 | 11.80 | 100 | 211.9 | |||||
120 | 8.276 | 10 | 145 | 30 | 113.6 | 125 | 33.0 | 30 | 14.16 | 125 | 264.8 | |||||
140 | 9.655 | 15 | 218 | 35 | 132.5 | 150 | 39.6 | 35 | 16.52 | 150 | 317.8 | |||||
500 | 34.48 | 20 | 290 | 40 | 151.4 | 175 | 46.2 | 40 | 18.88 | 175 | 370.7 | |||||
600 | 41.38 | 25 | 363 | 45 | 170.3 | 200 | 52.8 | 45 | 21.24 | 200 | 423.7 | |||||
700 | 48.28 | 30 | 435 | 50 | 189.3 | 225 | 59.4 | 50 | 23.60 | 225 | 476.7 | |||||
800 | 55.17 | 35 | 508 | 60 | 227.1 | 250 | 66.1 | 60 | 28.32 | 250 | 529.7 | |||||
900 | 62.07 | 40 | 580 | 70 | 265.0 | 300 | 79.3 | 70 | 33.04 | 300 | 635.6 | |||||
1,000 | 68.97 | 45 | 653 | 80 | 302.8 | 350 | 92.8 | 80 | 37.76 | 350 | 741.5 | |||||
1,200 | 82.76 | 50 | 725 | 90 | 340.7 | 400 | 106 | 90 | 42.48 | 400 | 847.5 | |||||
1,400 | 96.55 | 55 | 798 | 100 | 378.5 | 450 | 119 | 100 | 47.20 | 450 | 953.4 | |||||
1,600 | 110.3 | 60 | 870 | 125 | 473.1 | 500 | 132 | 125 | 58.99 | 500 | 1,059 | |||||
1,800 | 124.1 | 65 | 943 | 150 | 567.8 | 550 | 145 | 150 | 70.79 | 550 | 1,165 | |||||
2,000 | 137.9 | 70 | 1,015 | 175 | 662.4 | 600 | 159 | 175 | 82.59 | 600 | 1,271 | |||||
2,250 | 155.2 | 80 | 1,160 | 200 | 757.0 | 700 | 185 | 200 | 94.39 | 700 | 1,483 | |||||
2,500 | 172.4 | 100 | 1,450 | 225 | 851.6 | 800 | 211 | 225 | 106.2 | 800 | 1,695 | |||||
2,750 | 189.7 | 125 | 1,813 | 250 | 946.3 | 900 | 238 | 250 | 118.0 | 900 | 1,907 | |||||
3,000 | 206.9 | 150 | 2,175 | 275 | 1,041 | 1,000 | 264 | 275 | 129.8 | 1,000 | 2,119 | |||||
3,250 | 224.1 | 175 | 2,538 | 300 | 1,136 | 1,100 | 291 | 300 | 141.6 | 1,100 | 2,331 | |||||
3,500 | 241.4 | 200 | 2,900 | 325 | 1,230 | 1,200 | 317 | 325 | 153.4 | 1,200 | 2,542 | |||||
4,000 | 275.9 | 250 | 3,625 | 350 | 1,325 | 1,300 | 343 | 350 | 165.2 | 1,300 | 2,754 | |||||
4,500 | 310.3 | 300 | 4,350 | 375 | 1,420 | 1,400 | 370 | 375 | 177.0 | 1,400 | 2,966 | |||||
5,000 | 344.8 | 350 | 5,075 | 400 | 1,514 | 1,500 | 396 | 400 | 188.8 | 1,500 | 3,178 |
Note that a “liter” is equal to a “cubic decimeter (dm³)” but the liter is used for liquid measure while the dm³ is used for air and gas volume measurement.
Note also that a “bar” is used widely in fluid power for pressure measurement, but the standard SI unit for pressure is the pascal (Pa) or the kilopascal (kPa). One kPa is equal to 0.00145 PSI, a unit which is difficult to work with in most fluid power systems.
© 1990 by Womack Machine Supply Co. This company assumes no liability for errors in data nor in safe and/or satisfactory operation of equipment designed from this information.