This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X40N, 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 SI125X40N
The AirTAC SI125 Standard Cylinder SI125X40N is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 40mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X40N, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke40 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X40N
- 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 SI125X40N
The AirTAC SI125X40N is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 40 mm stroke. It delivers 6136 N push force at 0.5 MPa via a G1/2 port. The direct replacement is the SAI125X40N, matching the bore, stroke, force, port and ISO 15552 mounting interface.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure. This non-magnet SKU cannot take a sensor, unlike legacy CS1-B/DS1-B switches.
Airtac SI125 Standard Cylinder SI125X40N Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X40N |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X40N |
| Bore size | Ø125 mm |
| Stroke | 40 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 SAI125X40N 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 SAI125X40N 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 SI125X40N
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×40 | 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 SI125X40N Is Used
Heavy Pressing
Applies 6136 N at 0.5 MPa to seat large bearings or form heavy gauge metal components securely.
Mold Clamping
Holds substantial injection or stamping molds steady using the 125 mm bore and M27x2 rod thread.
Short Stroke Push
Executes brief 40 mm high-force transfers to index large payloads along assembly conveyors.
Replacing the Airtac SI125 Standard Cylinder SI125X40N with the SAI125X40N
To replace the SI125X40N, order the SAI125X40N. Confirm the ISO 15552 interface, 125 mm bore, 40 mm stroke, G1/2 port (PT/G/NPT), and mounting accessory. This NBR sealed unit runs -20 to +70 C; choose Viton H for up to 150 C. Being a no-SKU without a magnet, it cannot accept a sensor. If sizing alternatives, the 100 mm bore yields 3927 N [email protected], while the 160 mm bore yields 10053 N. For load holding on air loss, note the cushion only decelerates; use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X40N
- ✓ 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 SI125X40N FAQ
Yes, the SI125X40N is discontinued. The direct replacement is the SAI125X40N. It is dimensionally interchangeable per ISO 15552, retaining the same 125 mm bore, 40 mm stroke, 6136 N force, G1/2 port and mounting fixtures.
At 0.5 MPa it pushes 6136 N and pulls 5734 N. At 0.7 MPa push is 8590 N, and max theoretical force is 1251 kgf at 1.0 MPa. Operating speed is 30-500 mm/s. The G1/2 port and 40 mm cushion are fixed by the bore.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X40N
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X40N replacement — usually within 7-8 hours.