
KOSAPLUS RS90 Rack and Pinion Pneumatic Actuator
Your RS90 Code, Part By Part
Every letter of a KOSAPLUS code is one part of the actuator. Point at a part to see it in the code, and switch it to see how the code changes. O-ring and stem choices are the builds in the models table; action, colours and air connection keep the price.
Mechanism and size
Rack and Pinion, 90 mm
RS90 is the 90 mm cylinder (internal diameter). A bigger size gives more torque.
O-ring
NBR
The seals inside the actuator. Choose them for the temperature and the conditions around the actuator.
Non-standard: price on request
Spring
8 springs
Spring return models close (or open) by themselves when the air is lost. A stronger spring set closes with more force but leaves less torque for opening with air. See the catalogue torque tables.
Non-standard: price on request
Action
Action A: fail closed
Which way the actuator turns and where it goes if the air supply fails. A is the standard: fail closed, opening anticlockwise.
Non-standard: price on request
Body colour
Black (hard anodised)
Colour and finish of the aluminium body. Black is hard anodised, the standard finish.
Non-standard: price on request
End cap colour
Black
Colour of the end caps at each side of the body.
Non-standard: price on request
ISO 5211 flange
F07
The ISO 5211 mounting pattern under the actuator, which bolts to the valve's top flange. Several numbers mean it is drilled for each of them.
Stem
17 x 17 mm
The square drive that turns the valve stem, in mm. It comes from the size you choose.
Air connection
Standard PT 1/4 (no code)
The thread of the two air ports. PT is the standard (taper, like BSPT), NPT is the American taper thread and PF is a parallel thread (like BSPP).
Non-standard: price on request
RS90 Specifications
- Internal diameter
- 90 mm
- Operation
- Spring return
- O-ring
- NBR
- Spring
- 8 springs
- Action
- Action A: fail closed
- Body colour
- Black (hard anodised)
- End cap colour
- Black
- ISO 5211 flange
- F07
- Stem
- 17 x 17 mm
- Air connection
- Standard PT 1/4 (no code)
- Price
- Price on request
RS90 Drawings And CAD Files
Dimension drawing as PDF, CAD drawing (DWG) and 3D model (STEP) for the RS90.

The size you chose
RS90
- Diameter
- 90 mm
- ISO 5211
- F07