Airtac MFCJ Adjustable Mini Cylinder MFCJ40X125-40S
The AirTAC Airtac MFCJ Adjustable Mini Cylinder MFCJ40X125-40S 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 MFCJ40X125-40S
Trimming the extend stroke by up to 40 mm on-site is effortless with this double-acting mini cylinder, which pairs that external adjuster with a needle-set variable air cushion at both ends. The MFCJ40X125-40S features a JIS-standard SUS304 stainless round body and riveted aluminium covers, yielding a shorter mounting envelope than an ISO 6432 unit for the same bore and stroke while resisting mild washdown.
Driven by a 16 mm rod through a 1/4" port, this bore delivers 628.3 N of push force at 0.5 MPa (879.6 N at 0.7 MPa). That translates to a safe working load of roughly 377 N, or lifting about 32 kg vertically with a 2:1 margin. The -S suffix equips the piston with a magnet for CMSG, DMSG or EMSG sensors.
Airtac MFCJ Adjustable Mini Cylinder MFCJ40X125-40S Technical Specifications
| Model | Airtac MFCJ Adjustable Mini Cylinder MFCJ40X125-40S |
|---|---|
| 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 MFCJ40X125-40S
| 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 MFCJ40X125-40S Is Used
High-Speed Diverters
Tune the 40 mm extend window and needle cushions to softly push heavy cartons off a fast belt without slamming, absorbing shock at high cycle rates.
Machine Tending
Dial in the exact 85 to 125 mm reach for clamping oversized castings, leveraging the 628.3 N push force to secure parts during machining.
Dynamic Carton Sealing
Adjust the stroke on the fly for varying box heights while the variable air cushion ensures quiet, smooth retraction at 800 mm/s maximum speed.
Is the Airtac MFCJ Adjustable Mini Cylinder MFCJ40X125-40S the Right Cylinder?
When sizing this adjustable family, compare both bores directly: the 40 mm bore here yields 628.3 N push at 0.5 MPa, whereas the MFCJ32 provides 402.2 N. Choose the 40 mm variant when moving heavier fixtures or overcoming high friction at speed. The 40 mm adjust window and twin variable air cushions excel in high-speed changeovers and shock-sensitive trial fits where both the end position and deceleration need field tuning.
Mounting options include LB foot, FA flange and TC trunnion (there is no SDB or back-cover option). Remember that the air cushion only decelerates the piston near the end of stroke; it is not a brake. If the load must be held during air loss or valve centring, 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 MFCJ Adjustable Mini Cylinder MFCJ40X125-40S 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.
The external adjuster shortens the extend stroke by up to 40 mm on-site, giving a usable extend range of 85 to 125 mm. The -S suffix means a piston magnet is built-in for CMSG, DMSG or EMSG sensors. The variable air cushion at both ends only decelerates the piston near stroke end and does not lock the load.
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 MFCJ40X125-40S
Send us the quantity and destination. We confirm price, stock and lead time — usually within 7-8 hours.