Airtac MACJ Stainless Steel Mini Adjustable Cylinder MACJ40X30-20S
The AirTAC Airtac MACJ Stainless Steel Mini Adjustable Cylinder MACJ40X30-20S is a genuine double acting, adjustable stroke + cushion standard round-body mini air cylinder with a Ø40mm bore and 30mm 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
- Stroke30 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 MACJ40X30-20S
A compact 40 mm bore with real muscle: at 0.5 MPa the MACJ40X30-20S pushes 628.3 N and pulls 527.8 N, rising to 879.6 N push at 0.7 MPa. Air works on both faces, so the rod extends and retracts under power, and the extend stroke can be cut back by up to 20 mm with the built-in stop screw. Plan on roughly 377 N of usable work at 0.5 MPa instead of the full rating, and the rod will still lift about 64 kg vertically at peak.
The round stainless barrel and hard-chrome plated 16 mm rod shrug off washdown and damp shop air, a step up from painted minis in food or outdoor spots. Aluminium covers are rolled onto the tube for a sealed riveted body, and the piston magnet comes as standard, so CMSG, DMSG and EMSG switches clip straight on.
Airtac MACJ Stainless Steel Mini Adjustable Cylinder MACJ40X30-20S Technical Specifications
| Model | Airtac MACJ Stainless Steel Mini Adjustable Cylinder MACJ40X30-20S |
|---|---|
| Series | MACJ mini cylinder |
| Bore size | Ø40 mm |
| Stroke | 30 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 MACJ40X30-20S
| MACJ | Standard round-body mini cylinder (adjustable-stroke, variable cushion). |
|---|---|
| 40 | Bore size in mm. |
| ×30 | 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 MACJ40X30-20S Is Used
Bench punch station
Short 30 mm travel with 628 N push punches holes in sheet brackets and gaskets all day at up to 800 mm/s.
CNC jig clamping
Trim the 20 mm window to seat clamping jaws on aluminium plates without recutting the fixture.
Mold part ejection
Cushioned ejection nudges finished caps off a small mold without scarring the part face.
Is the Airtac MACJ Stainless Steel Mini Adjustable Cylinder MACJ40X30-20S the Right Cylinder?
Compare both neighbours before settling: the bore 32 MACJ delivers 402.2 N push at 0.5 MPa for lighter clamps, while a bore 50 jumps to 981.3 N if your jig grows. This 40 mm size sits comfortably in between. The stop screw only shortens the extend stroke and is not a mid-stroke lock - if air is lost the piston drifts, so add a check or locking valve where a load must stay put. FA flange and LB foot mounts, with I or Y knuckles on the rod, cover most fixtures; the magnet for switching is already fitted.
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 MACJ40X30-20S FAQ
At 0.5 MPa it pushes 628.3 N and pulls 527.8 N; at 0.7 MPa those rise to 879.6 N and 738.9 N. The theoretical maximum is 128.1 kgf at 1.0 MPa. Bore is 40 mm, rod is 16 mm hard-chrome steel, port is 1/8", rod thread M12x1.25, speed 30-800 mm/s, pressure 0.15-1.0 MPa (22-145 psi), proof 1.5 MPa (215 psi).
The stop screw limits the extend stroke anywhere within the 20 mm window, so the rod can stop short of the full 30 mm as needed. It is a mechanical end stop, not a mid-stroke lock - if air pressure drops the piston will drift. A variable air cushion at both ends lets you slow the piston into each end, so faster cycles or heavier loads arrive without hammering the covers.
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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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