This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X670S, 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 SI125X670S
The AirTAC SI125 Standard Cylinder SI125X670S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 670mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X670S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke670 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X670S
- 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 SI125X670S
The AirTAC SI125X670S is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 670 mm stroke. It delivers 6136 N push force at 0.5 MPa through a G1/2 port. AirTAC replaced this legacy unit with the SAI125X670S, a direct upgrade retaining the exact ISO 15552 mounting interface, M27x2 rod thread, and 40 mm cushions.
The SAI replacement features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life. The SAI family also introduces SAIL and BSAI lock variants absent in the SI line, and this -S SKU retains the magnet for CS1-B/DS1-B sensors.
Airtac SI125 Standard Cylinder SI125X670S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X670S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X670S |
| Bore size | Ø125 mm |
| Stroke | 670 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 SAI125X670S 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 SAI125X670S 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 SI125X670S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×670 | 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 SI125X670S Is Used
Heavy Press Clamping
Secures large metal castings during machining operations, utilizing the 6136 N push force at 0.5 MPa to hold components rigidly against the tooling bed.
Pallet Diversion
Actuates heavy-duty routing gates on automated assembly lines, relying on the 670 mm stroke to fully clear the pallet path for downstream processing.
Replacing the Airtac SI125 Standard Cylinder SI125X670S with the SAI125X670S
To replace the SI125X670S, order the SAI125X670S. Verify your ISO 15552 mounting accessory (LB, FA, TC, etc.), the G1/2 port, and the -S magnet requirement. Because this is a 670 mm stroke, add external guides to prevent rod bending and side-load damage. A plain cylinder drifts on air loss; cushions only decelerate. For load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant. If downsizing, a 100 mm bore gives 3927 N push @0.5 MPa; if upsizing, a 160 mm bore yields 10053 N.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X670S
- ✓ 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 SI125X670S FAQ
Yes, the SI125X670S is discontinued. The direct replacement is the SAI125X670S. It is dimensionally interchangeable per ISO 15552, matching the 125 mm bore, 670 mm stroke, output force, G1/2 port, and mounting interface.
This 125 mm bore cylinder uses a G1/2 air port. The thrust 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. Operating speed is 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X670S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X670S replacement — usually within 7-8 hours.