Airtac RMH Magnetic Coupling Rodless Cylinder RMH20X250S
Genuine AirTAC magnetic rodless cylinder, order code RMH20X250S from the RMH range. The options this code selects are decoded below; series data follow the official AirTAC catalog.
- BoreØ20 mm
- Stroke250 mm
- Port threadPT1/8
- ActionDouble acting, magnetic coupling
- GuideBuilt-in guide rail
- Ø10holding force 55 N · strokes to 300 mm
- No minimum order. A single piece can be ordered.
- Ready in 3–5 business days. That is the time we take to process the order and hand it to the carrier. Transit time after that depends on the destination.
About the Airtac RMH Magnetic Coupling Rodless Cylinder RMH20X250S
This code sits exactly on the 250 mm boundary of the catalog stroke tolerance: up to 250 mm the tolerance is +1.0/0 mm, and from 251 mm to 800 mm it loosens to +1.5/0 mm, so RMH20X250S is the longest Dia 20 RMH that keeps the tighter band. Travel comes from the magnetic coupling with no piston rod, so 250 mm still fits where a rod cylinder would not.
The Dia 20 coupling holds 220 N, ports are PT1/8 on one side, and both ends use fixed cushions on adjusting screws that can be replaced by separately ordered hydraulic shock absorbers. Sensors CMSH, DMSH and EMSH fit the built-in groove, the guide rail provides running and anti-rotation accuracy, and operating limits are 0.2-0.7 MPa, 50-400 mm/s and -20 to +70 C on air filtered to 40 um.
Airtac RMH Magnetic Coupling Rodless Cylinder RMH20X250S Technical Specifications
| Order code | RMH20X250S |
|---|---|
| Product | Magnetic Rodless Cylinder |
| Bore | Ø20 mm |
| Stroke | 250 mm |
| Port thread | PT1/8 |
| Action | Double acting, magnetic coupling |
|---|---|
| Guide | Built-in guide rail |
| Ø10 | holding force 55 N · strokes to 300 mm |
| Ø16 | holding force 140 N · strokes to 500 mm |
| Ø20 | holding force 220 N · strokes to 800 mm |
| Ø25 | holding force 345 N · strokes to 800 mm |
| Fluid | Air (filtered by 40 µm element) |
| Operating pressure | 0.2-0.7 MPa |
| Proof pressure | 1.2 MPa (175 psi) |
| Temperature | -20 to +70 °C |
| Speed | 50-400 mm/s |
| Stroke tolerance | +1.0 / 0 mm (≤250), +1.5 / 0 mm (251-800) |
| Cushion | Fixed, adjusting screws |
| Sensors | CMSH, DMSH, EMSH |
| Port | M5×0.8 (Ø10, 16), PT1/8 (Ø20, 25) |
Source: AirTAC Products Catalog 2026A (PDF01-P0612..P0613), RMH series specifications, load tables, strokes and ordering code.
How to choose
RMH20X250S is the Dia 20 choice when RMH20X200S is just short but you still want the +1.0/0 mm stroke tolerance; from 251 mm onward the catalog allows +1.5/0 mm. Load-wise the 3.6 / 6 kg Dia 20 load case runs to 500 mm and the allowed load falls with stroke, so check the datasheet load table for your mounting orientation. Below the needed thrust, RMH16X250S at 140 N saves size; above the 220 N holding force, step up to RMH25X250S at 345 N. G or NPT threads on Dia 20 are ordered with the G or T code instead of the PT1/8 default.
Applications
Sliding guard door
Drives a machine guard or cover panel open by 250 mm, with the sealed tube keeping contaminants out of the piston chamber.
Reject and present station
Pushes out-of-spec parts off the line over the full 250 mm travel, with the guide rail taking the side force.
Extend-and-retract fixture
Extends a jig, stop or product stop over 250 mm and retracts flush, staying within the tighter +1.0/0 mm stroke tolerance band.
FAQ
What are the key figures of RMH20X250S?
Dia 20 bore, 250 mm stroke with +1.0/0 mm tolerance, 220 N magnetic holding force, double acting magnetic coupling with guide rail, 0.2-0.7 MPa operating pressure (1.2 MPa / 175 psi proof), 50-400 mm/s, -20 to +70 C, PT1/8 ports, sensors CMSH, DMSH, EMSH.
Why does the 250 mm length matter for tolerance?
The catalog sets +1.0/0 mm stroke tolerance up to 250 mm and +1.5/0 mm for strokes of 251-800 mm, so this is the longest Dia 20 RMH that keeps the tighter band while still running at 50-400 mm/s on 0.2-0.7 MPa air.