Flo-Tork offers two types of optional manual overrides for the Series M actuators. For the smaller sizes, jackscrews with a square input shaft will be the most economical. For larger sizes, a self contained hydraulic hand pump will be needed. Other types of mechanical overrides may be provided but are not a standard Flo-Tork option. Consult Flo-Tork's Corporate office or your local Flo-Tork representative for your special requirements.
The following chart provides the required input torque to obtain the rated output torque at a given working presure (one jackscrew is required for a spring return unit and two jackscrews are required for a double acting unit).
| Lb-In Input Torque (lubricated - threads) | ||||
| Model | Working Pressure (PSIG) | |||
| 40 | 60 | 80 | 100 | |
| MD/MS 527 | 177 | 265 | 353 | 441 |
| MD/MS 727 | 346 | 520 | 693 | 866 |
| MD/MS 737 | 346 | 520 | 693 | 866 |
| MD/MS 837 | 452 | 679 | 905 | 1131 |
| MD/MS 937 | 573 | 859 | 1145 | 1431 |
| MD/MS 1037 | 707 | 1060 | 1414 | 1767* |
| MD/MS 1047 | 707 | 1060 | 1414 | 1767 |
| MD/MS 1247 | 1018 | 1527* | 2036* | NR |
| MD/MS 1447 | 1385 | 2078 | NR | NR |
*Use of a ratchet torque multiplier is recommended.
NR - Jackscrew overrides are not recommended for these sizes.
Hydraulic manual overrides are offered as an option for the larger actuators and will require an add-on hydraulic cylinder that is isolated from the power side for gas/air driven units. System schematics for the hydraulic override assemblies are illustrated below.