Airtac MACJ Stainless Steel Mini Adjustable Cylinder MACJ40X250-20S
The AirTAC Airtac MACJ Stainless Steel Mini Adjustable Cylinder MACJ40X250-20S is a genuine double acting, adjustable stroke + cushion standard round-body mini air cylinder with a Ø40mm bore and 250mm stroke, 1/8" air ports and a stainless-steel barrel with a hard-chrome-plated rod for reliable, mildly corrosion-resistant service. A variable air cushion at both ends lets you tune end-of-stroke deceleration on site.
- BoreØ40 mm
- Stroke250 mm
- Port size1/8"
- Acting typeDouble acting, adjustable stroke + cushion
- Rod threadM12×1.25
- 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 MACJ Stainless Steel Mini Adjustable Cylinder MACJ40X250-20S
Where a mid-size pusher needs a little on-site tuning, the MACJ40X250-20S pairs a 250 mm stroke with a 20 mm adjustable window on the extend side. It is double-acting, so air drives the rod both out and back, and a variable cushion at each end takes the sting out of end-of-stroke impact. Figures: 628.3 N push and 527.8 N pull at 0.5 MPa; 879.6 N and 738.9 N at 0.7 MPa; 128.1 kgf theoretical maximum at 1.0 MPa.
Built as a rolled round body - stainless tube, aluminium covers, hard-chrome plated 16 mm rod - it shrugs off condensation and washdown that would creep into painted mini cylinders. Working numbers worth remembering: about 377 N of realistic push at 0.5 MPa, roughly 64 kg of vertical lift at full pressure, or 32 kg with a 2:1 margin. The piston magnet is standard, so CMSG, DMSG or EMSG switches bolt on for end-position sensing.
Airtac MACJ Stainless Steel Mini Adjustable Cylinder MACJ40X250-20S Technical Specifications
| Model | Airtac MACJ Stainless Steel Mini Adjustable Cylinder MACJ40X250-20S |
|---|---|
| Series | MACJ mini cylinder |
| Bore size | Ø40 mm |
| Stroke | 250 mm |
| Acting type | Double acting, adjustable stroke + cushion |
| Port size | 1/8" |
| 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 | Variable air cushion, both ends |
| Max standard stroke | Up to 500 mm |
Specifications follow the official AirTAC MA-series datasheet. Barrel: stainless-steel tube (round-body, riveted rolling-packed construction); piston rod: carbon steel with 20µm hard-chrome plating; covers: aluminium alloy. Thread options: PT (blank) / G / NPT. Every MA-series cylinder ships with a built-in magnet for CMSG / DMSG / EMSG position sensors.
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 MACJ Stainless Steel Mini Adjustable Cylinder MACJ40X250-20S
| MACJ | Standard round-body mini cylinder (adjustable-stroke, variable cushion). |
|---|---|
| 40 | Bore size in mm. |
| ×250 | Stroke length in mm. |
| -20 | Adjustable stroke window (mm the extend stroke can be shortened on site). |
| -S | Built-in magnet for CMSG / DMSG / EMSG sensors (standard on MA series). |
| CA / U / CM | Back-cover type: CA pivot, U flat-end, CM round-end. |
MA-family variants: MA / MAC (double acting ±cushion), MSA / MTA (single acting push / pull), MAD / MACD (double rod ±cushion), MAJ / MACJ (adjustable stroke ±cushion), MAR (cushioned with integrated F/U mount). Mounting accessories: FA flange, LB foot, SDB pivot; plus I and Y knuckles. Thread PT (blank) / G / NPT.
Where the Airtac MACJ Stainless Steel Mini Adjustable Cylinder MACJ40X250-20S Is Used
Carton rejector at a sortation point
Kicking mislabelled boxes off a conveyor run; the 20 mm window matches the reject blade to the carton height.
Press-off ejector under a forming die
Dropping finished blanks from the die shoe on a cushioned 250 mm down-stroke.
Tooling clamp on a CNC fixture
Swinging or sliding a clamp arm into position, trimmed on site with the adjustable stop screw.
Is the Airtac MACJ Stainless Steel Mini Adjustable Cylinder MACJ40X250-20S the Right Cylinder?
One bore covers a wide band: 402.2 N at 0.5 MPa for the 32 mm and 981.3 N for the 50 mm, so pick 40 mm when the load sits between those. Mounting is FA flange or LB foot with I or Y knuckles where needed; ports are 1/8" (PT blank, G or NPT). The 20 mm window trims the extend stroke shorter after install - useful when fixture stops move - but it sets position only; with air lost the piston can still move, so it is not a load-holding brake.
Quick checklist
- ✓ Required force at your working pressure
- ✓ Stroke and mounting space
- ✓ Port/thread type (PT / G / NPT)
- ✓ Magnet (-S) is standard for sensors
- ✓ Back cover (CA/U/CM) & mount (FA/LB/SDB)
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 On first run, back off the cushion screws and release gradually.
- check Installation by qualified personnel per AirTAC docs.
Airtac MACJ Stainless Steel Mini Adjustable Cylinder MACJ40X250-20S FAQ
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; theoretical maximum 128.1 kgf at 1.0 MPa. For sizing, treat about 377 N as the practical push at 0.5 MPa.
An external stop screw shortens the extend stroke anywhere within the ordered 20 mm window - it trims, never lengthens past 250 mm. Because it is a mechanical stop, it sets position but will not hold a suspended load if supply air fails.
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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