Airtac MFJ Adjustable Mini Cylinder MFJ40X300-75
The AirTAC Airtac MFJ Adjustable Mini Cylinder MFJ40X300-75 is a genuine double acting, adjustable stroke JIS-standard round-body mini air cylinder with a Ø40mm bore and 300mm 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
- Stroke300 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 MFJ40X300-75
Trimming the extend stroke by up to 75 mm on site, the AirTAC MFJ40X300-75 lets you dial in the exact end position without buying a new cylinder or adding external stops. This JIS-standard round-body mini cylinder features a SUS304 stainless barrel and riveted aluminium covers, giving you a mounting envelope that is shorter than an ISO 6432 unit for the same 40 mm bore and 300 mm stroke.
Delivering 628.3 N of push force at 0.5 MPa, it 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, while fixed TPU bumper pads absorb end-of-stroke impact. Note this SKU lacks the -S magnet, so it cannot accept CMSG, DMSG or EMSG sensors.
Airtac MFJ Adjustable Mini Cylinder MFJ40X300-75 Technical Specifications
| Model | Airtac MFJ Adjustable Mini Cylinder MFJ40X300-75 |
|---|---|
| Series | MFJ JIS mini cylinder |
| Bore size | Ø40 mm |
| Stroke | 300 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 MFJ40X300-75
| MFJ | JIS-standard round-body mini cylinder (adjustable-stroke). |
|---|---|
| 40 | Bore size in mm. |
| ×300 | 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 MFJ40X300-75 Is Used
Changeover Stations
Dial in the extend position during product format changes using the 75 mm adjuster, leveraging the 628.3 N push force to shift heavy guide rails without swapping cylinders.
Prototype Test Rigs
Find the exact 225 to 300 mm extension needed for a new assembly process, safely moving test payloads up to 377 N before finalizing the machine design.
Variable Positioning Stops
Set precise end stops for different part lengths on the same line, letting the fixed TPU bumpers absorb the impact of the 40 mm bore piston at speeds up to 800 mm/s.
Is the Airtac MFJ Adjustable Mini Cylinder MFJ40X300-75 the Right Cylinder?
When sizing these adjustable cylinders, compare both bores directly: this MFJ40 delivers 628.3 N push at 0.5 MPa, whereas the MFJ32 provides 402.2 N. Choose the 40 mm bore when your trial fits or line changeovers need that extra thrust to move a load through a variable 225 to 300 mm extend window. If your load is lighter, the 32 mm bore saves space and air volume.
Remember that the external adjuster only shortens the extend stroke to fine-tune the position; it does not lock the piston mid-stroke. Because air drifts on loss of pressure, you must add an external rod lock or pilot check valve to hold a suspended load. For mounting, select LB foot, FA flange or TC trunnion brackets, as there is no SDB or back-cover option on this build.
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 MFJ40X300-75 FAQ
This 40 mm bore cylinder has 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 75 mm on site, giving a usable 225 to 300 mm extension. It only sets the end position and does not act as a mid-stroke lock; the fixed TPU bumpers just decelerate the piston. This SKU also lacks a magnet, so it cannot take 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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