This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125BX170S, 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 SI125BX170S
The AirTAC SI125 Standard Cylinder SI125BX170S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 170mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125BX170S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke170 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125BX170S
- 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 SI125BX170S
The AirTAC SI125BX170S is a discontinued double-acting ISO 15552 profile cylinder featuring a 125mm bore, 170mm stroke, and a SUS304 stainless piston rod. Delivering 6136N push force at 0.5MPa via a G1/2 port, it is replaced by the SAI125BX170S. This direct upgrade shares the exact ISO 15552 mounting interface, bore, and cushioning.
The SAI successor introduces an upgraded piston seal with two Y-shaped one-way elements for lower start-up pressure and longer life. The original -S magnet supports legacy CS1-B/DS1-B sensors, while the SAI family adds SAIL and BSAI lock variants absent in the SI line.
Airtac SI125 Standard Cylinder SI125BX170S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125BX170S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125BX170S |
| Bore size | Ø125 mm |
| Stroke | 170 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 SAI125BX170S 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 SAI125BX170S 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 SI125BX170S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×170 | 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 SI125BX170S Is Used
Heavy-Duty Pressing
Applies the 8590N push force at 0.7MPa to seat bearings and assemble heavy drivetrain components securely.
Pallet Dispensing
Handles robust lifting and indexing of loaded pallets, relying on the 313kg vertical lift margin for safe operation.
Stainless Rod Clamping
Utilizes the SUS304 rod for corrosion resistance when clamping parts in humid or washdown manufacturing environments.
Replacing the Airtac SI125 Standard Cylinder SI125BX170S with the SAI125BX170S
To replace the SI125BX170S, order the SAI125BX170S with the same ISO 15552 interface, 170mm stroke, G1/2 port, and SUS304 rod. Verify your mounting accessory (LB, FA, TC) and magnet requirement. If downsizing, a 100mm bore yields 3927N push at 0.5MPa; if upsizing, a 160mm bore provides 10053N. Because this stroke is under 300mm, standard rod-bending limits apply without needing external guides. Note that a plain cylinder drifts on air loss—the cushion only decelerates. For load holding, specify the SAIL or BSAI lock variant, or use an external pilot check valve.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125BX170S
- ✓ 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 SI125BX170S FAQ
Yes, the SI125BX170S is discontinued. The direct replacement is the SAI125BX170S. It shares the identical ISO 15552 mounting interface, 125mm bore, 170mm stroke, force, and G1/2 port, fitting existing fixtures perfectly.
The 125mm bore provides 6136N push and 5734N pull at 0.5MPa, 8590N push at 0.7MPa, 11045N at 0.9MPa, and a theoretical max of 1251kgf at 1.0MPa. Operating speed is 30-500mm/s, with a 40mm adjustable air cushion at both ends.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125BX170S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125BX170S replacement — usually within 7-8 hours.