Airtac MFCJ Adjustable Mini Cylinder MFCJ20X40-40S
The AirTAC Airtac MFCJ Adjustable Mini Cylinder MFCJ20X40-40S is a genuine double acting, adjustable stroke + cushion JIS-standard round-body mini air cylinder with a Ø20mm 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.
- BoreØ20 mm
- Stroke40 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 MFCJ20X40-40S
Dial in the extend end-point on-site with the AirTAC MFCJ20X40-40S, a JIS-standard round-body mini cylinder that lets you shorten the forward stroke by up to 40 mm via an external adjuster. The SUS304 stainless steel barrel and riveted aluminium covers form a compact body that is physically shorter than a comparable ISO 6432 unit, saving valuable mounting length while resisting mild corrosion and washdown.
Driven by filtered air at 0.15-1.0 MPa, this double-acting actuator generates 157 N of push force at 0.5 MPa. Needle-set variable air cushions at both ends soak up high-speed kinetic energy for smooth stops, and the -S suffix means a built-in piston magnet is fitted for CMSG, DMSG or EMSG position sensing. It connects via a 1/8" port and moves the 8 mm rod at 30-800 mm/s.
Airtac MFCJ Adjustable Mini Cylinder MFCJ20X40-40S Technical Specifications
| Model | Airtac MFCJ Adjustable Mini Cylinder MFCJ20X40-40S |
|---|---|
| Series | MFCJ JIS mini cylinder |
| Bore size | Ø20 mm |
| Stroke | 40 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 MFCJ20X40-40S
| MFCJ | JIS-standard round-body mini cylinder (adjustable-stroke, variable cushion). |
|---|---|
| 20 | 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 MFCJ20X40-40S Is Used
Micro-Clamp Trial Fitting
Use the 40 mm adjuster to micro-tune the extend position of a delicate clamping jaw, relying on the 157 N push force to secure light components without crushing them.
High-Speed Divertor
Soften the impact of rapid product diverting on a packaging line by dialling in the needle air cushion, ensuring the 8 mm rod retracts smoothly at up to 800 mm/s.
Lab Automation Stopper
Adjust the extend stroke on the fly for different test tube sizes; the SUS304 barrel handles light washdown, and the built-in magnet confirms the stopper position.
Is the Airtac MFCJ Adjustable Mini Cylinder MFCJ20X40-40S the Right Cylinder?
Choose the 20 mm bore when you need roughly 94 N of safe working load (about 60% of the 157 N push at 0.5 MPa) or to lift about 8 kg vertically with a 2:1 margin. If your trial fit requires more thrust, step up to the MFCJ25 which provides 245.3 N at 0.5 MPa. Both options share the same external stroke adjuster and needle cushion combination, ideal for high-speed changeovers where the exact end position and end-of-stroke shock both need tuning.
Mounting is limited to LB foot, FA flange or TC trunnion styles, with no SDB or back-cover option on this adjustable build. Because the -S magnet is present, you can directly fit CMSG, DMSG or EMSG switches. Remember that the air cushion only decelerates the piston near the stroke end; it does not lock or hold the load. If gravity or air loss could cause drift, 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 MFCJ20X40-40S FAQ
This 20 mm bore cylinder has an 8 mm rod, an M8x1.25 male thread, and a 1/8" port. The double-acting thrust is 157 N push and 131.9 N pull at 0.5 MPa, or 219.8 N push and 184.7 N pull at 0.7 MPa. The theoretical maximum force is 32 kgf at 1.0 MPa.
The external adjuster shortens the extend stroke by up to 40 mm on-site, while the retract stroke remains full. Needle-set variable air cushions at both ends decelerate the piston near the ends for smooth high-speed motion. The -S suffix indicates a built-in magnet for CMSG, DMSG or EMSG sensors.
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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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