Airtac MFJ Adjustable Mini Cylinder MFJ25X40-40S
The AirTAC Airtac MFJ Adjustable Mini Cylinder MFJ25X40-40S is a genuine double acting, adjustable stroke JIS-standard round-body mini air cylinder with a Ø25mm bore and 40mm stroke, 1/8" air ports and a SUS304 stainless-steel barrel for mildly corrosive environments. For the same bore and stroke it is shorter than an ISO 6432 cylinder, saving mounting space.
- BoreØ25 mm
- Stroke40 mm
- Port size1/8"
- Acting typeDouble acting, adjustable stroke
- Rod threadM10×1.25
- CushionFixed TPU bumper pads
- 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 MFJ Adjustable Mini Cylinder MFJ25X40-40S
Trimming the extend stroke by up to 40 mm on site, this double-acting JIS-standard round-body mini cylinder eliminates the need to buy a new unit or add external stops when the exact end position is not final. The riveted aluminium covers and SUS304 stainless steel barrel yield a shorter overall length than an ISO 6432 cylinder for the same 25 mm bore and 40 mm stroke, resisting mild corrosion and washdowns. A 1/8" port and Ø10 mm rod with an M10x1.25 male thread handle a 245.3 N push force at 0.5 MPa.
Because this SKU includes the -S magnet, it is ready for CMSG, DMSG or EMSG position switches. The adjuster fine-tunes the extend end point without acting as a mid-stroke lock, while fixed TPU bumper pads decelerate the piston at the stroke extremes. For vertical lifting, the 245.3 N output at 0.5 MPa provides a safe working load of roughly 147 N, lifting about 12.5 kg vertically with a 2:1 safety margin.
Airtac MFJ Adjustable Mini Cylinder MFJ25X40-40S Technical Specifications
| Model | Airtac MFJ Adjustable Mini Cylinder MFJ25X40-40S |
|---|---|
| Series | MFJ JIS mini cylinder |
| Bore size | Ø25 mm |
| Stroke | 40 mm |
| Acting type | Double acting, adjustable stroke |
| Port size | 1/8" |
| Rod thread | M10×1.25 |
| Fluid | Air (filtered by 40µm element) |
|---|---|
| Operating pressure | 0.15 – 1.0 MPa |
| Proof pressure | 1.5 MPa |
| Temperature | -20 to +70 °C |
| Speed range | 30 – 800 mm/s |
| Cushion | Fixed TPU bumper pads |
| Max standard stroke | Up to 500 mm |
Specifications follow the official AirTAC MF/MFC (JIS-standard) datasheet. Barrel: SUS304 stainless steel; covers: aluminum alloy (round-body, riveted rolling-packed construction). Thread options: PT (blank) / G / NPT.
Theoretical Output Force (Ø25mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 245 N | 206 N |
| 0.7 MPa | 344 N | 289 N |
| Max (@1.0 MPa) | 50 kgf | |
Actual usable force is lower than theoretical due to friction and back-pressure. Size with a safety margin.
Model Code: Airtac MFJ Adjustable Mini Cylinder MFJ25X40-40S
| MFJ | JIS-standard round-body mini cylinder (adjustable-stroke). |
|---|---|
| 25 | Bore size in mm. |
| ×40 | Stroke length in mm. |
| -S | Optional built-in magnet for CMSG / DMSG / EMSG sensors. |
MF-family variants: MF / MFC (double acting ±cushion), MSF / MTF (single acting push / pull), MFD / MFCD (double rod ±cushion), MFJ / MFCJ (adjustable stroke ±cushion). Back covers CA / U / CM. Mounting LB / FA / SDB / TC.
Where the Airtac MFJ Adjustable Mini Cylinder MFJ25X40-40S Is Used
Changeover Station Setup
Dial in the exact extend position during line changeovers using the 40 mm adjuster, delivering 245.3 N of push force to seat parts without adding external stops.
Prototyping Rigs
Fine-tune the end point on trial-fit assemblies where the final stroke length is unknown, leveraging the 12.5 kg vertical lift capacity for component testing.
Variable-Position Stops
Adjust the extend stroke on-site to accommodate different product sizes, using the built-in magnet and CMSG sensors to confirm the modified end position.
Is the Airtac MFJ Adjustable Mini Cylinder MFJ25X40-40S the Right Cylinder?
When sizing this series, compare the real thrust outputs: the MFJ20 delivers 157 N of push force at 0.5 MPa, this MFJ25 provides 245.3 N, and the larger MFJ32 offers 402.2 N. Choose the 25 mm bore when your changeover station or trial-fit rig needs moderate force within a compact footprint. The 40 mm adjustable window is particularly useful for prototyping lines where the final extend position is unknown, letting you dial in the exact stop without swapping hardware.
Mounting options include LB foot, FA flange and TC trunnion (no SDB or back-cover mount). Remember that the fixed TPU bumpers only decelerate the stroke end; the cylinder does not hold position on air loss. If the load must be prevented from drifting, install an external rod lock or pilot-operated check valve.
Quick checklist
- ✓ Required force at your working pressure
- ✓ Stroke and mounting space
- ✓ Port/thread type (PT / G / NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Back cover (CA/U/CM) & mount (LB/FA/SDB/TC)
Installation & Maintenance Notes
- check Use clean air filtered to 40µm or finer.
- check Keep within 0.15 – 1.0 MPa operating pressure.
- check Avoid side load on the piston rod.
- check Do not dismantle the riveted front/back covers.
- check Use correct back cover (CA/U/CM) & mount (LB/FA/SDB/TC).
- check Installation by qualified personnel per AirTAC docs.
Airtac MFJ Adjustable Mini Cylinder MFJ25X40-40S FAQ
This 25 mm bore cylinder uses a 1/8" port and a Ø10 mm rod. It generates a push force of 245.3 N and a pull force of 206.1 N at 0.5 MPa. At 0.7 MPa, the push force is 343.4 N and the pull is 288.5 N. The theoretical maximum force is 50 kgf at 1.0 MPa.
The external adjuster shortens the extend stroke by up to 40 mm on site, but it only sets the end position and does not act as a mid-stroke lock. Fixed TPU bumper pads decelerate the piston at the extremes. The -S suffix means it has a built-in piston magnet for CMSG, DMSG or EMSG switches.
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Genuine AirTAC parts produced by AirTAC factory.
1-Year Warranty
Covers non-human-caused product damage.
Fast Dispatch
Standard models are processed and dispatched in 3-5 business days.
Fast Reply
Most inquiries answered within 7-8 hours.
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