Airtac MFCJ Adjustable Mini Cylinder MFCJ20X125-40S
The AirTAC Airtac MFCJ Adjustable Mini Cylinder MFCJ20X125-40S is a genuine double acting, adjustable stroke + cushion JIS-standard round-body mini air cylinder with a Ø20mm bore and 125mm 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.
- BoreØ20 mm
- Stroke125 mm
- Port size1/8"
- Acting typeDouble acting, adjustable stroke + cushion
- Rod threadM8×1.25
- 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 MFCJ20X125-40S
Dial in exact end positions and absorb high-speed shock with the AirTAC MFCJ20X125-40S. This JIS-standard round-body mini cylinder features a 40 mm adjustable extend window, letting you trim the usable extend stroke down to 85 mm on-site, while the needle-set variable air cushion at both ends ensures smooth deceleration.
Built with a SUS304 stainless barrel and riveted aluminium covers, the riveted construction is shorter than an ISO 6432 cylinder of the same bore and stroke, saving valuable mounting length. Driven by a 1/8" port and Ø8 mm rod, it delivers 157 N of push force at 0.5 MPa. The integrated -S magnet supports CMSG, DMSG, and EMSG switches for position sensing. For a safe working load, expect around 94 N, lifting roughly 8 kg vertically with a 2:1 margin.
Airtac MFCJ Adjustable Mini Cylinder MFCJ20X125-40S Technical Specifications
| Model | Airtac MFCJ Adjustable Mini Cylinder MFCJ20X125-40S |
|---|---|
| Series | MFCJ JIS mini cylinder |
| Bore size | Ø20 mm |
| Stroke | 125 mm |
| Acting type | Double acting, adjustable stroke + cushion |
| Port size | 1/8" |
| Rod thread | M8×1.25 |
| 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 (Ø20mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 157 N | 132 N |
| 0.7 MPa | 220 N | 185 N |
| Max (@1.0 MPa) | 32 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 MFCJ20X125-40S
| MFCJ | JIS-standard round-body mini cylinder (adjustable-stroke, variable cushion). |
|---|---|
| 20 | 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 MFCJ20X125-40S Is Used
Light-Part Trial Fits
Use the 40 mm extend adjuster to micro-tune the push distance during changeovers on small component insertion lines, absorbing shock at speed.
High-Speed Diverting
Ideal for lightweight package routing where the variable air cushion quietly halts the 125 mm stroke, preventing bounce at 800 mm/s.
Lab Automation Jigs
The SUS304 barrel resists mild washdown in testing jigs, while the 94 N safe working load handles small sample trays precisely.
Is the Airtac MFCJ Adjustable Mini Cylinder MFCJ20X125-40S the Right Cylinder?
When sizing this series, compare the bores directly: this 20 mm bore yields 157 N push at 0.5 MPa, while stepping up to the MFCJ25 provides 245.3 N. Choose the 20 mm when the load is light and space is tight. The 40 mm adjustable window is perfect for high-speed changeovers where the exact extend point and end-of-stroke shock both need on-site tuning.
Remember that the air cushion only decelerates the piston near the end of travel; it is not a brake. If the application must hold a load on air loss, add an external rod lock or pilot-operated check valve, as the piston will drift. Mounting options include LB foot, FA flange, and TC trunnion (no SDB or back-cover). The -S magnet is already included for sensors.
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 MFCJ20X125-40S FAQ
This 20 mm bore cylinder features a 1/8" air port and an Ø8 mm rod. It generates 157 N push and 131.9 N pull at 0.5 MPa, 219.8 N push and 184.7 N pull at 0.7 MPa, with a theoretical maximum force of 32 kgf at 1.0 MPa.
The external adjuster shortens the extend stroke by up to 40 mm (usable extend 85-125 mm), while the variable air cushion at both ends decelerates the piston near stroke end. The -S suffix means it has a built-in 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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