This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X950S, 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 SI125X950S
The AirTAC SI125 Standard Cylinder SI125X950S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 950mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X950S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke950 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X950S
- 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 SI125X950S
The AirTAC SI125X950S is a discontinued double-acting ISO 15552 profile cylinder featuring an extruded aluminum barrel and a built-in piston magnet for CS1-B/DS1-B sensors. Delivering 6136 N push force at 0.5 MPa through a 125 mm bore and 950 mm stroke, it is replaced by the SAI125X950S. This direct successor matches the G1/2 port, M27x2 rod thread, and mounting interface exactly.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and extended life. The SAI family also adds SAIL and BSAI lock variants absent from the SI line, while rod material options include SUS420J2 or SUS304.
Airtac SI125 Standard Cylinder SI125X950S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X950S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X950S |
| Bore size | Ø125 mm |
| Stroke | 950 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 SAI125X950S 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 SAI125X950S 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 SI125X950S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×950 | 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 SI125X950S Is Used
Heavy Stamping Press
Drives large heavy-duty stamping dies requiring 6136 N of push force at 0.5 MPa over a 950 mm travel distance.
Pallet Transfer Unit
Shifts loaded pallets along extended 950 mm conveyor sections, utilizing the 313 kg vertical lift capacity.
Large Door Actuation
Opens and closes heavy industrial machinery access doors, benefiting from the 125 mm bore and G1/2 air port.
Replacing the Airtac SI125 Standard Cylinder SI125X950S with the SAI125X950S
To replace the SI125X950S, order the SAI125X950S. Verify the ISO 15552 mounting interface, 950 mm stroke, G1/2 port, and the -S magnet for legacy CS1-B/DS1-B switches (the SAI uses current AirTAC switches). Operating speed is 30-500 mm/s. For sizing alternatives, the neighboring 100 mm bore yields 3927 N push at 0.5 MPa, while the 160 mm bore provides 10053 N. Note that a plain cylinder drifts on air loss; the cushion only decelerates. For load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI variants. Because the 950 mm stroke is long, use external guides to prevent rod bending and side-load damage.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X950S
- ✓ 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 SI125X950S FAQ
Yes, the AirTAC SI125X950S is discontinued. The direct replacement is the SAI125X950S. It is dimensionally interchangeable per ISO 15552, retaining the same 125 mm bore, 950 mm stroke, output force, G1/2 port, and mounting fixtures.
This double-acting cylinder features a G1/2 air port. 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.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X950S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X950S replacement — usually within 7-8 hours.