Airtac JSI Series Standard Cylinder JSI125X300
The AirTAC Airtac JSI Series Standard Cylinder JSI125X300 is a genuine double acting JIS-standard air cylinder with a Ø125mm bore and 300mm stroke, G1/2 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.
- BoreØ125 mm
- Stroke300 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- CushionAdjustable, 33 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 JSI125X300
Delivering 6136 N of push force at 0.5 MPa, this double-acting JIS-standard profile cylinder handles heavy-duty automation with ease. Its extruded hard-anodized aluminum barrel contains no external rods, making the unit significantly shorter and more compact than an equivalent ISO 15552 cylinder of the same 125 mm bore. The internal two-way piston seal retains grease, ensuring long, low-friction operation even under high cycling stress.
Because this specific SKU lacks the -S magnet, it cannot accept CMSE or DMSE position switches. In practical terms, you can plan for roughly 3682 N of real work at 0.5 MPa, which means it lifts about 313 kg vertically with a 2:1 safety margin. The G1/2 air port and M27x2.0 rod thread provide robust connections for high-flow pneumatic demands, operating smoothly at 30-500 mm/s.
Airtac JSI Series Standard Cylinder JSI125X300 Technical Specifications
| Model | Airtac JSI Series Standard Cylinder JSI125X300 |
|---|---|
| Series | JSI JIS-standard profile cylinder |
| Bore size | Ø125 mm |
| Stroke | 300 mm |
| Acting type | Double acting |
| Port size | G1/2 |
| Rod thread | M27×2.0 |
| 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 – 500 mm/s |
| Cushion | Adjustable, 33 mm |
| Max standard stroke | Up to 1500 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 (Ø125mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 6136 N | 5734 N |
| 0.7 MPa | 8590 N | — |
| Max (@1.0 MPa) | 1251 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 JSI125X300
| JSI | JIS-standard profile cylinder (double-acting type). |
|---|---|
| 125 | Bore size in mm (32 / 40 / 50 / 63 / 80 / 100 / 125). |
| ×300 | 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 JSI125X300 Is Used
Injection Mold Clamping
Provides the heavy 6136 N push at 0.5 MPa needed to secure large injection mold halves, utilizing the compact JIS profile to save valuable machine footprint.
Pallet Positioning
Shifts loaded pallets weighing up to 313 kg vertically with a 2:1 margin, where the hard-anodized barrel resists wear in dusty logistics hubs.
Press Ejection
Ejects dense stamped metal parts from hydraulic presses, relying on the 33 mm adjustable air cushions to absorb impact at the end of the 300 mm stroke.
Is the Airtac JSI Series Standard Cylinder JSI125X300 the Right Cylinder?
When sizing this 125 mm bore, stepping down to a 100 mm bore drops the output to 3927 N at 0.5 MPa, while 125 mm is the largest available JSI option. For holding a suspended load vertically, remember that exhausting the air or centering the valve causes the piston to drift—the adjustable 33 mm cushions only decelerate the stroke at the ends and do not act as a brake. You must fit an external rod lock or pilot-operated check valve to secure the load. Additionally, at this 300 mm stroke length, side-load forces can bend the 32 mm rod, so mounting external guides is strongly recommended to prevent premature seal wear.
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 JSI125X300 FAQ
This 125 mm bore cylinder features a G1/2 air port and an M27x2.0 rod thread. The thrust outputs are 6136 N push and 5734 N pull at 0.5 MPa, 8590 N push and 8028 N pull at 0.7 MPa, with a theoretical maximum of 1251 kgf at 1.0 MPa.
No, this specific SKU does not include a magnet. You must choose the -S variant to use CMSE or DMSE switches in the side grooves. Without the magnet, external mechanical limit switches are required for end-of-stroke confirmation.
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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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