This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X370SN, 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 SI125X370SN
The AirTAC SI125 Standard Cylinder SI125X370SN is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 370mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X370SN, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke370 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X370SN
- 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 SI125X370SN
The AirTAC SI125X370SN is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 370 mm stroke. It delivers 6136 N push force at 0.5 MPa. AirTAC replaced it with the SAI125X370SN, a direct upgrade retaining the exact ISO 15552 mounting interface, G1/2 port, and M27x2 rod thread.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. The NBR seals handle -20 to +70 C, while Viton H extends this to 150 C. This -S model carries a piston magnet for legacy CS1-B/DS1-B sensors.
Airtac SI125 Standard Cylinder SI125X370SN Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X370SN |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X370SN |
| Bore size | Ø125 mm |
| Stroke | 370 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 SAI125X370SN 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 SAI125X370SN 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 SI125X370SN
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×370 | 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 SI125X370SN Is Used
Heavy Stamping Press
Drives large tooling dies with 6136 N thrust at 0.5 MPa, utilizing the 370 mm stroke to clear bulky workpieces during press cycling.
Pallet Positioning Gate
Shifts heavy loaded pallets on conveyor lines, where the 125 mm bore output and ISO 15552 profile durability handle high radial loads.
Automated Assembly Lift
Raises substantial machinery sub-components into place, relying on the 313 kg vertical lift capacity and adjustable 40 mm cushions.
Replacing the Airtac SI125 Standard Cylinder SI125X370SN with the SAI125X370SN
To replace this SI with the SAI125X370SN, verify the ISO 15552 mounting fixture, 125 mm bore, 370 mm stroke, G1/2 port (PT/G/NPT), and the -S magnet for position sensing. If downsizing, a 100 mm bore yields 3927 N at 0.5 MPa; if upsizing, a 160 mm bore provides 10053 N. For this 370 mm stroke, use an external guide to prevent rod bending and side-load wear. A plain cylinder drifts without live air; the cushion only decelerates. For load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X370SN
- ✓ 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 SI125X370SN FAQ
Yes, the AirTAC SI125X370SN is discontinued. The direct replacement is the SAI125X370SN. It is dimensionally interchangeable per ISO 15552, keeping the same 125 mm bore, 370 mm stroke, G1/2 port, and mounting accessories, but adds an upgraded piston seal.
The bore is 125 mm with a G1/2 air port and M27x2 rod thread. At 0.5 MPa it pushes 6136 N and pulls 5734 N. At 0.7 MPa push is 8590 N, and at 0.9 MPa it is 11045 N. The theoretical max force is 1251 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X370SN
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X370SN replacement — usually within 7-8 hours.