This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X245S, 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 SI125X245S
The AirTAC SI125 Standard Cylinder SI125X245S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 245mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X245S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke245 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X245S
- 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 SI125X245S
The AirTAC SI125X245S is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 245 mm stroke. It delivers 6136 N push and 5734 N pull at 0.5 MPa, utilizing a G1/2 port and M27x2 rod thread. The direct replacement is the SAI125X245S, which maintains the identical ISO 15552 mounting interface, bore, stroke, output force, and porting to fit existing fixtures seamlessly.
The SAI upgrade features a modernized piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. The SI-S magnet supports legacy CS1-B/DS1-B sensors, while the SAI family introduces SAIL, SAIF, and BSAI lock and valve variants absent in the legacy line.
Airtac SI125 Standard Cylinder SI125X245S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X245S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X245S |
| Bore size | Ø125 mm |
| Stroke | 245 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 SAI125X245S 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 SAI125X245S 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 SI125X245S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×245 | 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 SI125X245S Is Used
Heavy Press Clamping
Ideal for securing heavy metal components during machining or stamping, utilizing the 6136 N push force at 0.5 MPa to hold parts firmly in manufacturing fixtures.
Large Package Diversion
Powers heavy-duty diverter arms on high-throughput conveyor lines, using the 245 mm stroke to push large industrial cartons off the main belt path.
Replacing the Airtac SI125 Standard Cylinder SI125X245S with the SAI125X245S
To replace the SI125X245S, order the SAI125X245S. Verify your ISO 15552 mounting accessory (LB, FA, TC, etc.), the G1/2 port thread (PT, G, or NPT), and the -S magnet requirement for current AirTAC switches. Note that 245 mm is a nonstandard stroke; ensure it matches your fixture. Sizing both ways: if you need less force, the 100 mm bore offers 3927 N push at 0.5 MPa; if you need more, the 160 mm bore provides 10053 N. For loads requiring holding on air loss, a plain cylinder drifts; the cushion only decelerates. Use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant. For any stroke over 300 mm, guide the load to prevent rod bending and side-load wear.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X245S
- ✓ 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 SI125X245S FAQ
Yes, the AirTAC SI125X245S is discontinued. The direct replacement is the SAI125X245S. It is dimensionally interchangeable per ISO 15552, retaining the same 125 mm bore, 245 mm stroke, G1/2 port, and mounting interface, so it drops directly into existing fixtures.
This double-acting cylinder has a G1/2 port and a 32 mm rod. The force 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 SAI125X245S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X245S replacement — usually within 7-8 hours.