The distinctive feature of the ACTUATECH product range are the quarter-turn pneumatic Scotch Yoke actuators. Alternative system to the classic Rack & Pinion, which has numerous advantages, including increased torque and lower air consumption, with consequent energy savings.
The diagram shows the torque development during the valve cycle from close to open and close again.
1. Rack & Pinion flat torque
2. Scotch Yoke canted torque
3. Represent the typical valve torque
The blue area between the Rack & Pinion and Scotch Yoke diagrams shows the Motive Energy Saving, easily verified comparing the compressed air consumption stated in our data table and any Rack & Pinion manufacturer.
BTOV: Break Torque to Open Valve
BTOA: Break Torque to Open Actuator
BTOA = BTOV+SF (Safety Factor)
The diagram shows the torque development during the valve cycle from close to open and close again.
1. Rack & Pinion flat torque
2. Scotch Yoke canted torque
3. Represent the typical valve torque
The blue area between the Rack & Pinion and Scotch Yoke diagrams shows the Motive Energy Saving, easily verified comparing the compressed air consumption stated in our data table and any Rack & Pinion manufacturer.
BTOV: Break Torque to Open Valve
BTOA: Break Torque to Open Actuator
BTOA = BTOV+SF (Safety Factor)
The scotch yoke system starts its cycle with the higher torque that helps the valve high breakaway torque required at the first opening phase.
The special double on one sealing fascia grants a longer life maintenance free without Oring sticking and replacement.
The bearing force transmission between the pistons and the driving shaft reduces the friction, compared to the rack and gear direct contact.
In comparison with the Rack & Pinion system, the Scotch Yoke system used in the same cylinder bore, with equal air pressure thanks to its mechanical construction develops a higher torque. Less air consumption = less energy consumption.
| Scotch-Yoke ACTUATECH | Rack & Pinion COMPETITOR |
| GD30 = 30Nm 0,12 l/cycle | 30Nm 0,4 l/cycle |
GD480 = 480Nm 2,0 l/cycle | 480Nm 6,2 l/cycle |
With reference to the above bore difference, the overall dimensions for the Scotch Yoke are minors than the R & P actuator, consequently the Scotch Yoke actuators are less in weight.
| Scotch-Yoke ACTUATECH | Rack & Pinion COMPETITOR |
| GD30 = 30Nm 1,0 Kg | 30Nm 1,5 Kg |
GD480 = 480Nm 8,2 Kg | 480Nm 14,5 Kg |
Stainless steel gives a suitable corrosion protection against the polluted and aggressive environment, better than the actuator with drive shaft nickel plated protected.
The fine internal finishing with extra lapping works reduces the roughness and increases the life of the sliding PTFE parts.
The Scotch Yoke in spring return actuator gives a final increasing torque that grants a perfect sealing of the valve especially in the closing phase (the spring force works right on the piston axis).
