Airtac MFCJ Adjustable Mini Cylinder MFCJ25X40-20S
The AirTAC Airtac MFCJ Adjustable Mini Cylinder MFCJ25X40-20S is a genuine double acting, adjustable stroke + cushion 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 + cushion
- Rod threadM10×1.25
- CushionVariable air cushion, both ends
- 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 MFCJ Adjustable Mini Cylinder MFCJ25X40-20S
Tune both the extend distance and end-of-stroke shock on site with this 25 mm bore, 40 mm stroke adjustable cylinder. The external adjuster shortens the extend stroke by up to 20 mm (usable range 20-40 mm), while the needle variable air cushion at both ends soaks up high-speed impact for smooth, quiet motion.
Built as a JIS-standard round-body mini with a SUS304 stainless barrel and riveted aluminium covers, it packs a 245.3 N push force at 0.5 MPa through a 1/8" port. The body is shorter than an ISO 6432 cylinder for the same stroke, saving mounting length. With a safe working load around 147 N, it lifts about 12.5 kg vertically. The -S suffix means a built-in magnet is present for CMSG, DMSG or EMSG switches.
Airtac MFCJ Adjustable Mini Cylinder MFCJ25X40-20S Technical Specifications
| Model | Airtac MFCJ Adjustable Mini Cylinder MFCJ25X40-20S |
|---|---|
| Series | MFCJ JIS mini cylinder |
| Bore size | Ø25 mm |
| Stroke | 40 mm |
| Acting type | Double acting, adjustable stroke + cushion |
| 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 | Variable air cushion, both ends |
| 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 MFCJ Adjustable Mini Cylinder MFCJ25X40-20S
| MFCJ | JIS-standard round-body mini cylinder (adjustable-stroke, variable cushion). |
|---|---|
| 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 MFCJ Adjustable Mini Cylinder MFCJ25X40-20S Is Used
Light Tooling Trial Fits
Dial in the exact extend position within the 20 mm window during prototype runs, letting the air cushion absorb high-speed impacts without jarring delicate 245.3 N-class assemblies.
Package Divert Stroke Tuning
Fine-tune the pusher stroke on the fly for varying carton sizes, using the cushion to keep the retract and extend quiet at up to 800 mm/s.
Lab Dispense Head Positioning
Set the precise extend end for a liquid dispense head, relying on the SUS304 barrel for mild washdown resistance and the -S magnet for position confirmation.
Is the Airtac MFCJ Adjustable Mini Cylinder MFCJ25X40-20S the Right Cylinder?
Weigh this 25 mm bore against the adjacent sizes: the MFCJ20 delivers 157 N of push force at 0.5 MPa, while the MFCJ32 jumps to 402.2 N. At 245.3 N push (206.1 N pull) at 0.5 MPa, this model hits a sweet spot for lighter tooling. Choose it when you need to dial in the exact extend end position during high-speed changeovers or shock-sensitive trial fits.
Mount using LB foot, FA flange or TC trunnion brackets (there is no SDB or back-cover option). The variable air cushion only decelerates the piston near the end of travel; it is not a brake. If the load must hold position on air loss, add an external rod lock or pilot 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 MFCJ Adjustable Mini Cylinder MFCJ25X40-20S FAQ
It has a 1/8" port and 10 mm rod. The double-acting thrust is 245.3 N push and 206.1 N pull at 0.5 MPa, 343.4 N push and 288.5 N pull at 0.7 MPa, with a theoretical max of 50 kgf at 1.0 MPa.
The external adjuster shortens the extend stroke by up to 20 mm (usable range 20-40 mm), and the needle variable air cushion decelerates the piston at both ends. The cushion is not a brake; the cylinder will drift on air loss, so use an external rod lock to hold a load. The -S magnet allows CMSG, DMSG or EMSG sensors.
Authorized Export Seller
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.
Related AirTAC MFCJ Cylinders
Request a Quote for Airtac MFCJ Adjustable Mini Cylinder MFCJ25X40-20S
Send us the quantity and destination. We confirm price, stock and lead time — usually within 7-8 hours.