Airtac MKJ Adjustable Cylinder MKJ25X40-20S
The AirTAC Airtac MKJ Adjustable Cylinder MKJ25X40-20S is a genuine MK multi-mount cylinder (adjustable stroke), 25 mm bore. Its compact square body fixes from six directions and mounts side by side to save space. It delivers about 245.4 N of push force at 0.5 MPa. A bumper cushions the impact. As an MK unit a fixed rod stops the piston rod rotating.
- TypeMulti-mount, adjustable stroke
- SeriesMK (no-rotating)
- Bore25 mm
- Push thrust @0.5 MPa245.4 N
- Operating pressure0.15 - 1.0 MPa (22 - 145 psi)
- Port sizeM5x0.8
- CushionBumper
- MagnetWith magnet (sensor-ready)
- ThreadPT
- 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 MKJ Adjustable Cylinder MKJ25X40-20S
The MKJ25X40-20S is a compact AirTAC multi-mount cylinder that fixes from six directions - front, back, left, right, top and bottom - so several units can sit side by side on a machine to save space. Magnetic-switch slots run around the square body for clean sensor fitting, and the body gives high guide precision without added lubrication. With a 25 mm bore in double-acting service it delivers a theoretical push force of 245.4 N at 0.5 MPa, and its cushion is a bumper for end-of-stroke damping. The adjustable-stroke format adds a 20 mm adjustment range on top of the 40 mm base stroke.
This is a genuine AirTAC part in the MK family, where a no-rotating plate, brass bushing and fixed rod stop the piston rod from turning - unlike the standard MD family, where rotation is allowed. The trailing S in the code shows this SKU is fitted with a magnet for position sensing. Medium is air filtered to 40 um; proof pressure is 1.5 MPa (215 psi) and the temperature range is -20 to 70 C (up to 0-150 C only with the optional high-temperature seal material). Typical materials are aluminium-alloy body and covers, a stainless or S45C rod and NBR seals; confirm exact bore-specific details and dimensions from the datasheet on request.
Airtac MKJ Adjustable Cylinder MKJ25X40-20S Technical Specifications
| Model | Airtac MKJ Adjustable Cylinder MKJ25X40-20S |
|---|---|
| Type | Multi-mount cylinder, adjustable stroke |
| Series | MK (no-rotating) |
| Bore | 25 mm |
| Push thrust @0.5 MPa | 245.4 N |
| Port size | M5x0.8 (PT thread) |
| Magnet | With magnet (S) |
| Fluid | Air, filtered to 40 um |
|---|---|
| Operating pressure | 0.15 - 1.0 MPa (22 - 145 psi) |
| Proof pressure | 1.5 MPa (215 psi) |
| Temperature | -20 to 70 C |
| Speed range | 30 - 500 mm/s |
| Cushion | Bumper |
| Mounting | Fix from 6 directions; mountable side by side |
Specifications follow the official AirTAC MD/MK multi-mount data. The front cover and piston are short, so avoid an over-long stroke. An optional high-temperature seal material extends the range to 0 to 150 C. Overall dimensions vary per stroke and allowable side-load is published as curves — ask us and we confirm from the datasheet.
How to choose
Choose the 25 mm bore when your clamp or positioning job needs the bore's 245.4 N theoretical push at 0.5 MPa on the push side. MK vs MD is the rotation decision: this MKJ model prevents rod rotation via a no-rotating plate, while MD allows it. The double-acting MKJ gives 30-500 mm/s and operates at 0.15-1.0 MPa, with a 10/20/30 mm adjustable range added to the base stroke - here 20 mm on top of 40 mm. Stroke is limited to 60 mm for this bore in double-acting service, and the short covers caution against over-long strokes; if your application applies side-load, confirm limits with us from the datasheet. The S suffix means the magnet is fitted; PT thread is standard and G is available.
Applications
Small-parts clamping
Clamps fixtures or small machined parts on an assembly station, using the no-rotating rod to keep the clamp pad flat against the part without spinning out of alignment.
Pick-and-place units
Drives the horizontal slide of a compact pick-and-place head, where the side-by-side multi-mount layout saves panel space and the fixed rod orientation keeps the gripper square.
Jig positioning
Positions jigs and workpiece stops on a fixture plate with the 20 mm adjustable stroke range, letting operators dial in exact stop height without changing cylinders.
FAQ
What does the adjustable stroke on the MKJ25X40-20S mean in practice?
The 40 mm base stroke is fixed, and the J format adds a 20 mm adjustable range on top, giving an effective stroke window of 40-60 mm. Double-acting bores of 20/25/32 mm allow strokes up to 60 mm, so this model sits at the top of the 25 mm table. Check the datasheet for exact dimension details per stroke.
How do I mount this cylinder and where do I find its dimensions?
The square multi-mount body fixes from six directions - front, back, left, right, top and bottom - so units can be bolted side by side to save space, with sensor slots around the body. Overall dimensions depend on stroke and bore, so confirm them from the datasheet; if your application applies side-load, contact us and we will confirm the limits with you.