Airtac MFCJ Adjustable Mini Cylinder MFCJ40X250-20
The AirTAC Airtac MFCJ Adjustable Mini Cylinder MFCJ40X250-20 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 MFCJ40X250-20
Tune both the extend end-position and the end-of-stroke shock on-site with the AirTAC MFCJ40X250-20. This double-acting JIS-standard round-body mini cylinder features a 20 mm adjustable window, letting you shorten the nominal 250 mm extend stroke down to 230 mm, while the retract stroke remains full length. A needle variable air cushion at both ends soaks up high-speed kinetic energy for smooth, quiet operation.
Built with a SUS304 stainless steel barrel and riveted aluminium covers, the body is purposefully shorter than an ISO 6432 cylinder for the same 40 mm bore and stroke, saving valuable mounting length while resisting mild corrosion and washdown. The 1/4" port and M14x1.5 male rod thread handle a robust force class, pushing 628.3 N at 0.5 MPa. For practical sizing, this bore yields a safe working load around 377 N, lifting about 32 kg vertically with a 2:1 margin. Note this SKU lacks the -S magnet, so it cannot take CMSG, DMSG, or EMSG switches.
Airtac MFCJ Adjustable Mini Cylinder MFCJ40X250-20 Technical Specifications
| Model | Airtac MFCJ Adjustable Mini Cylinder MFCJ40X250-20 |
|---|---|
| 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 MFCJ40X250-20
| 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 MFCJ40X250-20 Is Used
High-Speed Machining Clamps
Dial in the 230-250 mm extend position for oversized workpieces while the variable air cushion absorbs the high-speed impact of the 628.3 N thrust during automated clamping.
Dynamic Diverters
Fine-tune the actuator reach on transfer lines by up to 20 mm to accommodate different carton sizes, relying on the cushion to soften the stroke end at high cycling speeds.
Palletizing Stops
Adjust the physical stop position on the fly for mixed-load pallet builds, using the 40 mm bore's 377 N safe working load to halt items reliably without harsh slamming.
Is the Airtac MFCJ Adjustable Mini Cylinder MFCJ40X250-20 the Right Cylinder?
When choosing between the two available bores, size by your dynamic force needs: this MFCJ40 delivers 628.3 N push at 0.5 MPa, whereas the smaller MFCJ32 provides 402.2 N. Select the 40 mm bore if your high-speed changeover or shock-sensitive trial fit demands the higher thrust, and use the 20 mm external adjuster to dial in the exact 230 to 250 mm extend position. The variable air cushion needle must be set to decelerate the load smoothly near the stroke end.
Mounting options include LB foot, FA flange, and TC trunnion (there is no SDB or back-cover code on this build). Because this specific SKU has no -S magnet, position sensing is unavailable; add the -S option if you require CMSG, DMSG, or EMSG switches. Remember that the air cushion and adjuster only manage motion and end-position—they do not lock or hold the load. If your application must prevent drift on air loss, install an external rod lock or a 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 MFCJ40X250-20 FAQ
This 40 mm bore cylinder features a 1/4" port and an M14x1.5 male rod thread. It delivers 628.3 N push and 527.8 N pull at 0.5 MPa, 879.6 N push and 738.9 N pull at 0.7 MPa, with a theoretical maximum force of 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 230-250 mm), while the needle variable air cushion at both ends decelerates the load near the stroke end.
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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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