This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X490, 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 SI125X490
The AirTAC SI125 Standard Cylinder SI125X490 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 490mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X490, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke490 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X490
- 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 SI125X490
The AirTAC SI125X490 is a discontinued double-acting ISO 15552 profile cylinder featuring a 125mm bore and 490mm stroke. It delivers 6136 N push force at 0.5 MPa through a G1/2 port. AirTAC replaced this legacy unit with the SAI125X490, a direct upgrade retaining the exact ISO 15552 mounting interface, bore, stroke, and output force.
The SAI successor introduces an upgraded piston seal with two Y-shaped one-way elements for lower start-up pressure and longer life. Note this specific SKU lacks a magnet (-S), so it cannot accept CS1-B/DS1-B sensors.
Airtac SI125 Standard Cylinder SI125X490 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X490 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X490 |
| Bore size | Ø125 mm |
| Stroke | 490 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 SAI125X490 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 SAI125X490 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 SI125X490
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×490 | 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 SI125X490 Is Used
Heavy Stamping Press
Drives large platens and stamping dies requiring substantial 6136 N thrust at 0.5 MPa over a 490mm travel distance.
Large Mold Handling
Shifts heavy injection molds along the 490mm stroke, relying on external guides to prevent rod bending.
Replacing the Airtac SI125 Standard Cylinder SI125X490 with the SAI125X490
To replace the SI125X490, order the SAI125X490, verifying your ISO 15552 mounting accessory (LB, FA, TC, etc.) and G1/2 port thread (PT, G, or NPT). Because this 490mm stroke exceeds 300mm, use external guides to prevent rod bending and side-load damage. If you need to downsize, a 100mm bore yields 3927 N at 0.5 MPa; if you need more force, a 160mm bore provides 10053 N. This plain cylinder cannot hold a load without live air—its 40mm cushions only decelerate. For secure load holding, specify the SAIL or BSAI lock variant, or use an external pilot check valve.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X490
- ✓ 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 SI125X490 FAQ
Yes, the SI125X490 is discontinued. The direct replacement is the SAI125X490. It shares the identical ISO 15552 mounting interface, 125mm bore, 490mm stroke, G1/2 port, and output force, fitting your existing fixtures perfectly.
The 125mm bore uses a G1/2 port with a 32mm rod. 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.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X490
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X490 replacement — usually within 7-8 hours.