Airtac MFCJ Adjustable Mini Cylinder MFCJ40X125-20
The AirTAC Airtac MFCJ Adjustable Mini Cylinder MFCJ40X125-20 is a genuine double acting, adjustable stroke + cushion JIS-standard round-body mini air cylinder with a Ø40mm bore and 125mm 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
- Stroke125 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 MFCJ40X125-20
Tune extend travel precisely on-site with the AirTAC MFCJ40X125-20, a JIS-standard round-body mini cylinder. The external adjuster shortens the 125 mm extend stroke by up to 20 mm, yielding a 105-125 mm usable window, while the needle variable air cushion at both ends soaks up high-speed shock. It features a SUS304 stainless barrel and riveted aluminium covers, giving a shorter mounting length than an ISO 6432 unit for the same bore.
This 40 mm bore double-acting actuator pushes with 628.3 N and pulls with 527.8 N at 0.5 MPa, peaking at a theoretical 128.1 kgf at 1.0 MPa. It yields a safe working load of roughly 377 N, lifting about 32 kg vertically with a 2:1 margin. Fitted with a 1/4" port and a 16 mm rod, this specific SKU lacks the -S magnet and therefore cannot accept CMSG, DMSG, or EMSG switches.
Airtac MFCJ Adjustable Mini Cylinder MFCJ40X125-20 Technical Specifications
| Model | Airtac MFCJ Adjustable Mini Cylinder MFCJ40X125-20 |
|---|---|
| Series | MFCJ JIS mini cylinder |
| Bore size | Ø40 mm |
| Stroke | 125 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 MFCJ40X125-20
| MFCJ | JIS-standard round-body mini cylinder (adjustable-stroke, variable cushion). |
|---|---|
| 40 | Bore size in mm. |
| ×125 | 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 MFCJ40X125-20 Is Used
High-Speed Forming Press
Dial in the 105-125 mm extend window and tune the needle air cushion to absorb shock when stamping parts at high speed, leveraging the 628.3 N push force.
Heavy Transfer Diverter
Divert heavier product streams on a line using the robust 40 mm bore, adjusting the stroke by up to 20 mm on-site to hit the exact conveyor lane position.
Pallet Stopper Gate
Halt pallets securely using the 128.1 kgf maximum theoretical force, relying on the variable air cushion for quiet deceleration during rapid cycling.
Is the Airtac MFCJ Adjustable Mini Cylinder MFCJ40X125-20 the Right Cylinder?
Compare this 40 mm bore against the smaller MFCJ32: the 32 mm bore yields 402.2 N of push force at 0.5 MPa, whereas this MFCJ40 delivers 628.3 N. Choose the 40 mm when moving heavier payloads, ensuring your pressure stays within the 0.15-1.0 MPa operating range. The adjustable 20 mm window and variable air cushion are ideal for high-speed changeovers or shock-sensitive trial fits where you must dial in the exact end position and deceleration.
Mounting options include LB foot, FA flange, and TC trunnion (no SDB or back-cover code exists for this build). Remember that the air cushion only decelerates the piston near stroke end—it is not a brake. If the application must hold a load vertically on air loss, fit an external rod lock or pilot-operated check valve, as the piston will drift. Since this is a non-magnet SKU, add the -S option if you need position sensing.
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 MFCJ40X125-20 FAQ
This 40 mm bore cylinder uses a 1/4" port and a 16 mm rod. It generates 628.3 N push and 527.8 N pull at 0.5 MPa, or 879.6 N push and 738.9 N pull at 0.7 MPa. The theoretical maximum force is 128.1 kgf at 1.0 MPa.
This specific SKU lacks the -S magnet, so it cannot accept CMSG, DMSG, or EMSG switches. The external adjuster shortens the extend stroke by up to 20 mm (usable range 105-125 mm), while the variable air cushion at both ends handles deceleration.
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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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