Airtac MI25~40 Stainless Steel Mini Cylinder MI40X400SU
The AirTAC Airtac MI25~40 Stainless Steel Mini Cylinder MI40X400SU is a genuine double acting round-body mini air cylinder with a Ø40mm bore and 400mm stroke, 1/4" air ports and a stainless-steel barrel and rod for mildly corrosive environments.
- BoreØ40 mm
- Stroke400 mm
- Port size1/4"
- Acting typeDouble acting
- Rod threadM12×1.25
- 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 MI25~40 Stainless Steel Mini Cylinder MI40X400SU
Delivering 628.3 N of push force at 0.5 MPa, this double-acting round-body mini cylinder handles heavy-duty linear motion across its 400 mm travel. The stainless-steel barrel and Ø16 mm piston rod shrug off mild corrosion, making it highly suitable for damp washdown environments where painted steel alternatives degrade. Riveted construction keeps the unit compact, while the built-in piston magnet (-S) directly supports CMSG, DMSG, and EMSG electronic or reed switches for precise end-of-stroke detection. A 90-degree U back cover provides flexible port and mounting orientation.
For practical sizing, plan for roughly 377 N of actual work at 0.5 MPa, which translates to lifting about 32 kg vertically with a safe 2:1 margin. Fixed TPU bumper pads absorb the impact at the stroke extremes to protect the mechanics. Air enters via a 1/4 inch port, and the male M12x1.25 rod thread ensures a robust attachment point for heavier payloads.
Airtac MI25~40 Stainless Steel Mini Cylinder MI40X400SU Technical Specifications
| Model | Airtac MI25~40 Stainless Steel Mini Cylinder MI40X400SU |
|---|---|
| Series | MI mini cylinder |
| Bore size | Ø40 mm |
| Stroke | 400 mm |
| Acting type | Double acting |
| Port size | 1/4" |
| Rod thread | M12×1.25 |
| 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 | Fixed TPU bumper pads |
| Max standard stroke | Up to 500 mm |
Specifications follow the official AirTAC MI/MIC (ISO 6432) datasheet. Barrel & rod: stainless steel (round-body, riveted construction). Thread options: PT (blank) / G. Note: the Ø40 bore is a larger, non-ISO-6432 size.
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 MI25~40 Stainless Steel Mini Cylinder MI40X400SU
| MI | round-body mini cylinder (double-acting). |
|---|---|
| 40 | Bore size in mm. |
| ×400 | Stroke length in mm. |
| -S | Optional built-in magnet for CMSG / DMSG / EMSG sensors. |
MI-family variants: MI / MIC (double acting ±cushion), MSI / MTI (single acting push / pull), MID / MICD (double rod ±cushion), MIJ / MICJ (adjustable stroke ±cushion). Back covers CA / U / R / CM. Mounting LB / FA / SDB / TC.
Where the Airtac MI25~40 Stainless Steel Mini Cylinder MI40X400SU Is Used
Pallet Diverter Gate
Actuates heavy routing gates on packaging lines, using the 628.3 N thrust to push loaded pallets onto secondary conveyors.
Stamping Press Feed
Drives a 400 mm feed mechanism to push metal blanks into a stamping press, relying on the stainless build to resist shop coolant.
Vertical Crate Lifter
Lifts approximately 32 kg filled crates between floor levels, using the 90-degree U cover to optimize the rear pivot mounting.
Is the Airtac MI25~40 Stainless Steel Mini Cylinder MI40X400SU the Right Cylinder?
When sizing this 40 mm bore, compare your actual load against the 628.3 N push rating at 0.5 MPa. If your application requires less force, stepping down to the Ø32 bore provides 402.2 N of push; since Ø40 is the largest available round-body mini cylinder in this series, exceeding this capacity requires moving to a different family. For the 400 mm stroke, ensure your mounting configuration—such as an LB foot or FA flange—prevents rod side-loading, as long strokes are susceptible to bending forces.
Remember that a standard double-acting cylinder relies entirely on continuous air pressure to maintain its position. If the air supply drops or the directional valve is centred, the piston will drift, and the TPU bumpers only soften the end-of-stroke impact rather than locking the load. To suspend a load safely during an air loss event, integrate an external pilot-operated check valve or a dedicated rod lock.
Quick checklist
- ✓ Required force at your working pressure
- ✓ Stroke and mounting space
- ✓ Port/thread type (PT / G)
- ✓ Magnet (-S) for sensors?
- ✓ Back cover (CA/U/R/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/R/CM) & mount (LB/FA/SDB/TC).
- check Installation by qualified personnel per AirTAC docs.
Airtac MI25~40 Stainless Steel Mini Cylinder MI40X400SU FAQ
This 40 mm bore cylinder features a 1/4 inch air port and a male M12x1.25 rod thread. It generates 628.3 N push and 527.8 N pull at 0.5 MPa, increasing to 879.6 N push and 738.9 N pull at 0.7 MPa. The theoretical maximum force is 128.1 kgf at 1.0 MPa.
No, the fixed TPU bumper pads only decelerate the piston at the stroke end; they do not function as a brake. The piston will drift if air pressure is lost or the valve is centred. An external rod lock or pilot check valve is required to hold a suspended load.
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1-Year Warranty
Covers non-human-caused product damage.
Fast Dispatch
Standard models are processed and dispatched in 3-5 business days.
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Most inquiries answered within 7-8 hours.
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