This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X120SN, 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 SI125X120SN
The AirTAC SI125 Standard Cylinder SI125X120SN is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 120mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X120SN, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke120 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X120SN
- 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 SI125X120SN
The AirTAC SI125X120SN is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 120 mm stroke. It delivers 6136 N push force at 0.5 MPa via a G1/2 port. The direct replacement is the SAI125X120SN, matching the interface, bore, stroke, force and mounting.
The SAI upgrade features two Y-shaped one-way piston seals for low start-up pressure and long life. It also adds SAIL, SAIF and BSAI variants the SI lacked. The NBR seals handle -20 to +70 C, while Viton H extends this to 150 C.
Airtac SI125 Standard Cylinder SI125X120SN Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X120SN |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X120SN |
| Bore size | Ø125 mm |
| Stroke | 120 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 SAI125X120SN 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 SAI125X120SN 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 SI125X120SN
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×120 | 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 SI125X120SN Is Used
Heavy Stamping Press
Drives large heavy-duty stamping dies requiring substantial thrust, utilizing the 6136 N push force at 0.5 MPa to form thick metal components reliably.
Industrial Clamp Fixture
Secures large fabricated steel frames for welding operations, providing the high clamping pressure needed to prevent workpiece shifting during manufacturing.
Replacing the Airtac SI125 Standard Cylinder SI125X120SN with the SAI125X120SN
To replace the SI125X120SN, order the SAI125X120SN. Confirm the ISO 15552 mounting interface, 120 mm stroke, G1/2 port (PT/G/NPT thread), M27x2 rod thread and the -S magnet for CS1-B/DS1-B switches (the SAI uses current AirTAC switches). If you need more force than the 6136 N at 0.5 MPa, step up to a 160 mm bore; if less is required, a 100 mm bore provides 3927 N. A plain cylinder drifts on air loss as the 40 mm cushion only decelerates, so use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant for held loads. Rod material options include carbon steel, SUS420J2 or SUS304.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X120SN
- ✓ 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 SI125X120SN FAQ
Yes, the SI125X120SN is discontinued. The direct replacement is the SAI125X120SN. It is dimensionally interchangeable per the ISO 15552 mounting interface, retaining the same 125 mm bore, 120 mm stroke, force, G1/2 port and mounting accessories, so it drops directly into existing fixtures.
The 125 mm bore cylinder operates at 0.15-1.0 MPa (proof 1.5 MPa) with a speed of 30-500 mm/s. Force output is 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. It features a 32 mm rod, M27x2 thread, and 40 mm adjustable cushions.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X120SN
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X120SN replacement — usually within 7-8 hours.