This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X125, with the same bore, stroke, output force, port and mounting, so it fits the same application. The SAI replacement keeps the same ISO 15552 mounting interface, bore, stroke, output force and accessories, so it drops straight into existing fixtures. It is the current-production version of this cylinder with an upgraded piston seal.
Airtac SI125 Standard Cylinder SI125X125
The AirTAC SI125 Standard Cylinder SI125X125 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 125mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X125, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke125 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X125
- 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 SI125 Standard Cylinder SI125X125
The AirTAC SI125X125 is a discontinued double-acting ISO 15552 profile cylinder, delivering a push force of 6136 N at 0.5 MPa through its 125 mm bore and 125 mm stroke. It features a 32 mm carbon steel piston rod, an M27x2 rod-end thread, a G1/2 air port, and 40 mm adjustable air cushions at both ends. Because this SKU lacks a magnet, it cannot accept a position sensor.
You should order the direct replacement SAI125X125, which preserves the exact ISO 15552 mounting interface, bore, stroke, output force, and port size. The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and long life. The SAI family also adds SAIL and BSAI lock variants absent from the legacy SI line.
Airtac SI125 Standard Cylinder SI125X125 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X125 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X125 |
| Bore size | Ø125 mm |
| Stroke | 125 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, 40 mm |
| Max standard stroke | Up to 1500 mm |
Specifications follow the official AirTAC SI datasheet (now discontinued). The SAI125X125 carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
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 | |
The SAI125X125 produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SI125 Standard Cylinder SI125X125
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×125 | Stroke length in mm. |
| -S | Optional built-in magnet for sensor position sensing. |
Legacy SI-family variants: SID (double rod), SIJ (adjustable stroke) — each maps to its SAI equivalent (SID→SAID, SIJ→SAIJ). Rod material: carbon steel (blank) / SUS420J2 (A) / SUS304 (B).
Where the Airtac SI125 Standard Cylinder SI125X125 Is Used
Heavy Press Clamping
Secures large metal castings during machining, using the 6136 N push force to maintain rigid fixturing under heavy cutting loads.
Bulk Material Diversion
Actuates heavy-duty diverter arms on high-throughput packaging lines, relying on the 40 mm adjustable cushions to absorb kinetic energy.
Replacing the Airtac SI125 Standard Cylinder SI125X125 with the SAI125X125
To replace the SI125X125, order the SAI125X125. Confirm the ISO 15552 mounting fixture, the 125 mm stroke, the G1/2 port (available in PT, G, or NPT), and your mounting accessory (such as LB foot or TC trunnion). Since this specific legacy SKU has no magnet, it cannot support sensing; if you require position feedback, select an SAI125X125S and use current AirTAC switches. For sizing context, a neighbouring 100 mm bore provides 3927 N push at 0.5 MPa, while a 160 mm bore offers 10053 N. A standard SAI does not hold load without live air; the cushion only decelerates. For load holding on air loss, use an external rod lock, a pilot check valve, or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X125
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SI125 Standard Cylinder SI125X125 FAQ
Yes, the AirTAC SI125X125 is discontinued. The direct replacement is the SAI125X125. It is dimensionally interchangeable per ISO 15552, matching the 125 mm bore, 125 mm stroke, G1/2 port, and mounting interface, so it fits existing fixtures directly.
This 125 mm bore cylinder has a G1/2 air port. The thrust ratings are 6136 N push and 5734 N pull at 0.5 MPa, 8590 N push at 0.7 MPa, 11045 N push at 0.9 MPa, and a theoretical maximum of 1251 kgf at 1.0 MPa. Operating speed is 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X125
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X125 replacement — usually within 7-8 hours.