Airtac JSI Series Standard Cylinder JSI40X125S
The AirTAC Airtac JSI Series Standard Cylinder JSI40X125S is a genuine double acting JIS-standard air cylinder with a Ø40mm bore and 125mm stroke, G1/4 air ports and adjustable end cushioning. Its no-tie-rod, hard-anodized profile barrel is more compact than an ISO 15552 cylinder of the same bore — a space-saver on tight machines.
- BoreØ40 mm
- Stroke125 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM14×1.5
- CushionAdjustable, 20.5 mm
- 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 JSI Series Standard Cylinder JSI40X125S
Delivering 628 N of push force at 0.5 MPa, this double-acting 40 mm bore JIS-standard profile cylinder is purposefully shorter and more compact than a same-bore ISO 15552 unit, saving valuable machine space. The extruded hard-anodized aluminum barrel omits external rods to resist wear, while a two-way piston seal retains grease for long, low-friction life. A built-in piston magnet is included, allowing CMSE or DMSE electronic switches to drop directly into the side grooves for position detection.
At 0.5 MPa you can plan for roughly 377 N of real work, which translates to lifting about 32 kg vertically with a 2:1 safety margin. The G1/4 air port feeds the 16 mm carbon steel rod, and adjustable 20.5 mm air cushions at both ends decelerate the piston smoothly across its 125 mm travel at speeds of 30-800 mm/s.
Airtac JSI Series Standard Cylinder JSI40X125S Technical Specifications
| Model | Airtac JSI Series Standard Cylinder JSI40X125S |
|---|---|
| Series | JSI JIS-standard profile cylinder |
| Bore size | Ø40 mm |
| Stroke | 125 mm |
| Acting type | Double acting |
| Port size | G1/4 |
| 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 | Adjustable, 20.5 mm |
| Max standard stroke | Up to 1200 mm |
Specifications follow the official AirTAC JSI (JIS standard) datasheet. Confirm against the product label before installation. Thread options: PT (blank) / G. Barrel: hard-anodized aluminum profile (no tie rods).
Theoretical Output Force (Ø40mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 628 N | 528 N |
| 0.7 MPa | 880 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 JSI Series Standard Cylinder JSI40X125S
| JSI | JIS-standard profile cylinder (double-acting type). |
|---|---|
| 40 | Bore size in mm (32 / 40 / 50 / 63 / 80 / 100 / 125). |
| ×125 | Stroke length in mm. |
| -S | Optional built-in magnet for CMSE / DMSE sensors. |
JSI-family variants: JSI (double acting), JSID (double rod), JSIJ (adjustable stroke). Mounting: LB / FA / FB / CA / CB / CR / TC / TCM1 / TCM2. Thread PT (blank) / G.
Where the Airtac JSI Series Standard Cylinder JSI40X125S Is Used
Package Diverting Gate
Actuates a routing flap on a packaging conveyor, using the 125 mm stroke to redirect cartons into a secondary lane with reliable 528 N pull force.
Small Part Ejection
Pushes machined aluminum components out of a CNC fixture, where the compact profile saves space and the 628 N push easily clears the part.
Vertical Label Press
Moves a pneumatic label applicator down onto containers, lifting about 32 kg safely with a 2:1 margin while the -S magnet confirms the press position.
Is the Airtac JSI Series Standard Cylinder JSI40X125S the Right Cylinder?
This 40 mm bore hits a practical middle ground, but sizing both ways helps confirm the fit: step down to a 32 mm bore for lighter 402 N tasks, or move up to a 50 mm bore if you need 982 N of push force at 0.5 MPa. Because this SKU includes the -S magnet, it is fully ready for CMSE or DMSE position sensing; a non-S variant cannot accept these switches.
Remember that a standard cylinder drifts if air pressure drops or the valve is centered, as the air cushion only decelerates the stroke near the end points rather than locking the load. For vertical or suspended loads that must hold position securely during an air loss event, install an external rod lock or a pilot-operated check valve.
Quick checklist
- ✓ Required force at your working pressure
- ✓ Stroke and mounting space
- ✓ Port/thread type (PT / G / NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Side load — consider a guided cylinder
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 Set cushions to minimum, then release gradually.
- check Use correct mounting accessory (LB/FA/FB/CA/CB/TC).
- check Installation by qualified personnel per AirTAC docs.
Airtac JSI Series Standard Cylinder JSI40X125S FAQ
The 40 mm bore features a G1/4 air port and a 16 mm rod with an M14x1.5 thread. It generates 628 N push and 528 N pull at 0.5 MPa, 879 N push and 739 N pull at 0.7 MPa, and a theoretical maximum of 128 kgf at 1.0 MPa.
The JSI series follows JIS standards and uses an extruded hard-anodized aluminum barrel without external rods, making it shorter and more compact than an ISO 15552 cylinder of the same bore. It is not dimensionally interchangeable with ISO 15552, but offers significant space savings on tight machinery.
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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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