Airtac MFJ Adjustable Mini Cylinder MFJ40X50-20
The AirTAC Airtac MFJ Adjustable Mini Cylinder MFJ40X50-20 is a genuine double acting, adjustable stroke JIS-standard round-body mini air cylinder with a Ø40mm bore and 50mm 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
- Stroke50 mm
- Port size1/4"
- Acting typeDouble acting, adjustable stroke
- Rod threadM14×1.5
- CushionFixed TPU bumper pads
- 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 MFJ Adjustable Mini Cylinder MFJ40X50-20
Trimming the extend stroke by up to 20 mm on site, the AirTAC MFJ40X50-20 lets you dial in the exact end position without swapping hardware. This JIS-standard round-body mini cylinder uses a SUS304 stainless barrel and riveted aluminium covers, yielding a shorter overall length than an ISO 6432 unit for the same 40 mm bore and 50 mm stroke.
Delivering 628.3 N of push force at 0.5 MPa, it easily handles a safe working load of about 377 N or lifts roughly 32 kg vertically with a 2:1 margin. The 1/4" port and M14x1.5 male rod thread match the 40 mm bore class. Note this SKU lacks a magnet, so it cannot accept CMSG/DMSG/EMSG switches; fixed TPU bumpers decelerate the stroke ends.
Airtac MFJ Adjustable Mini Cylinder MFJ40X50-20 Technical Specifications
| Model | Airtac MFJ Adjustable Mini Cylinder MFJ40X50-20 |
|---|---|
| Series | MFJ JIS mini cylinder |
| Bore size | Ø40 mm |
| Stroke | 50 mm |
| Acting type | Double acting, adjustable stroke |
| 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 | Fixed TPU bumper pads |
| 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 MFJ Adjustable Mini Cylinder MFJ40X50-20
| MFJ | JIS-standard round-body mini cylinder (adjustable-stroke). |
|---|---|
| 40 | Bore size in mm. |
| ×50 | 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 MFJ Adjustable Mini Cylinder MFJ40X50-20 Is Used
Changeover Stations
Fine-tune the 50 mm extend stroke down by 20 mm during product changeovers, using the 628.3 N push force to shift heavier tooling.
Trial Fit Rigs
Dial in the exact end position on prototype assemblies without machining new stops, leveraging the 32 kg vertical lift capacity.
Variable Position Stops
Adjust the extend endpoint on the fly for flexible manufacturing layouts where the final contact position is not yet finalized.
Is the Airtac MFJ Adjustable Mini Cylinder MFJ40X50-20 the Right Cylinder?
When sizing these adjustable cylinders, compare the bores directly: the MFJ40 pushes 628.3 N at 0.5 MPa, while the smaller MFJ32 pushes 402.2 N. Choose the 40 mm bore if your trial fits or line changeovers require moving heavier fixtures within that 30 to 50 mm usable extend window. Both options feature an external adjuster that shortens the extend end without adding external stops.
Mount this unit via LB foot, FA flange, or TC trunnion (no SDB or back-cover option exists). Remember that the bumper only decelerates the stroke end—it does not lock the piston. If air pressure drops, the rod drifts, so install an external rod lock or pilot check valve for held loads.
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 MFJ Adjustable Mini Cylinder MFJ40X50-20 FAQ
This 40 mm bore cylinder features a 1/4" port and an M14x1.5 male rod thread. It generates 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 of 128.1 kgf at 1.0 MPa.
The external adjuster shortens the extend stroke by up to 20 mm (usable extend 30-50 mm) to set the end position; it is not a mid-stroke lock. Fixed TPU bumpers only decelerate the stroke end. Because this SKU lacks a magnet (-S), it cannot take CMSG/DMSG/EMSG switches.
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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