Airtac MFCJ Adjustable Mini Cylinder MFCJ40X250-20S
The AirTAC Airtac MFCJ Adjustable Mini Cylinder MFCJ40X250-20S is a genuine double acting, adjustable stroke + cushion JIS-standard round-body mini air cylinder with a Ø40mm bore and 250mm stroke, 1/4" 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.
- BoreØ40 mm
- Stroke250 mm
- Port size1/4"
- Acting typeDouble acting, adjustable stroke + cushion
- Rod threadM14×1.5
- 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 MFCJ40X250-20S
Dial in exact extend lengths on-site with the AirTAC MFCJ40X250-20S, a JIS-standard round-body mini cylinder featuring a 20mm adjustable stroke window and variable air cushions at both ends. Built with a SUS304 stainless barrel and riveted aluminium covers, it is shorter than an ISO 6432 cylinder for the same 40mm bore and 250mm stroke, saving valuable machine space while resisting mild washdown corrosion. Driven by a 16mm rod through a 1/4" port, it delivers a robust 628.3N push force at 0.5MPa.
This double-acting actuator allows you to fine-tune the extend end position from 230mm to 250mm, making it ideal for trial fits where end-of-stroke shock also requires tuning via the needle cushions. The built-in -S magnet supports CMSG, DMSG, and EMSG sensors for position confirmation. For sizing, it yields a safe working load of roughly 377N, meaning it lifts about 32kg vertically with a 2:1 margin.
Airtac MFCJ Adjustable Mini Cylinder MFCJ40X250-20S Technical Specifications
| Model | Airtac MFCJ Adjustable Mini Cylinder MFCJ40X250-20S |
|---|---|
| Series | MFCJ JIS mini cylinder |
| Bore size | Ø40 mm |
| Stroke | 250 mm |
| Acting type | Double acting, adjustable stroke + cushion |
| Port size | 1/4" |
| Rod thread | M14×1.5 |
| 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 (Ø40mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 628 N | 528 N |
| 0.7 MPa | 880 N | 739 N |
| Max (@1.0 MPa) | 128 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 MFCJ40X250-20S
| MFCJ | JIS-standard round-body mini cylinder (adjustable-stroke, variable cushion). |
|---|---|
| 40 | Bore size in mm. |
| ×250 | 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 MFCJ40X250-20S Is Used
Adjustable Press Fit
Fine-tune the 230-250mm extend stroke on the fly for delicate pressing tasks, using the needle cushion to absorb high-speed impact without damaging the workpiece.
Changeover Diverter
Swap product sizes quickly by adjusting the extend end position up to 20mm, relying on the 628.3N push force to redirect heavy packages on a conveyor line.
Vertical Lift Assist
Lift approximately 32kg loads vertically with a 2:1 safety margin, using the SUS304 stainless body to withstand humid or lightly washed warehouse environments.
Is the Airtac MFCJ Adjustable Mini Cylinder MFCJ40X250-20S the Right Cylinder?
When choosing between this MFCJ40 and the smaller MFCJ32, compare your actual force needs: the 40mm bore provides 628.3N push at 0.5MPa, whereas the 32mm bore offers 402.2N. Select this MFCJ40X250-20S for high-speed changeovers or shock-sensitive trial fits where you must externally tune the extend stroke within the 20mm window and dial in the needle air cushion for smooth deceleration. Mount using LB foot, FA flange, or TC trunnion brackets (no SDB available). Note that the air cushion and adjuster only decelerate the piston; they do not lock or hold the load. If air pressure drops, the piston will drift, so install an external rod lock or pilot check valve for suspended loads.
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 MFCJ40X250-20S FAQ
This 40mm bore cylinder uses a 1/4" port and a 16mm rod with an M14x1.5 male thread. It generates 628.3N push and 527.8N pull at 0.5MPa, 879.6N push and 738.9N pull at 0.7MPa, with a theoretical maximum of 128.1kgf at 1.0MPa.
The external adjuster shortens the extend stroke by up to 20mm (usable range 230-250mm), while the variable air cushion at both ends decelerates the piston near stroke end for smooth stops. The cushion is not a brake; the cylinder cannot hold position on air loss, so use an external rod lock for suspended loads. The -S suffix means it includes a magnet for 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.
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