This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125BX145S, 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 SI125BX145S
The AirTAC SI125 Standard Cylinder SI125BX145S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 145mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125BX145S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke145 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125BX145S
- 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 SI125BX145S
The AirTAC SI125BX145S is a discontinued double-acting ISO 15552 profile cylinder featuring a 125 mm bore, 145 mm stroke, and a SUS304 stainless steel rod. It delivers 6136 N push and 5734 N pull at 0.5 MPa, utilizing a G1/2 air port and M27x2 rod thread. AirTAC replaced this legacy unit with the SAI125BX145S, a direct replacement sharing the exact ISO 15552 mounting interface, output force, and dimensions.
The SAI upgrade introduces a refined piston seal with two Y-shaped one-way elements for lower start-up pressure and extended life. This -S model includes a piston magnet for legacy CS1-B/DS1-B sensors, while the SAI accepts current AirTAC switches.
Airtac SI125 Standard Cylinder SI125BX145S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125BX145S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125BX145S |
| Bore size | Ø125 mm |
| Stroke | 145 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 SAI125BX145S 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 SAI125BX145S 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 SI125BX145S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×145 | 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 SI125BX145S Is Used
Heavy Stamping Press
Drives large platens and heavy dies requiring high thrust, using the 6136 N push force at 0.5 MPa to form thick metal components securely.
Washdown Ejection
Utilizes the SUS304 stainless rod option to eject large parts from food-grade or chemical washdown environments without surface corrosion.
Replacing the Airtac SI125 Standard Cylinder SI125BX145S with the SAI125BX145S
To replace the SI125BX145S, order the SAI125BX145S, confirming the ISO 15552 mounting interface, 145 mm stroke, and G1/2 port (PT/G/NPT thread options). Retain your original mounting accessory (LB, FA, TC, etc.) and the -S magnet requirement. The -B rod material denotes SUS304 stainless steel, ideal for corrosive environments compared to the standard carbon steel rod. If sizing up or down, neighbouring bores are 100 mm and 160 mm; at 0.5 MPa, the 100 mm bore yields 3927 N push, while the 160 mm bore yields 10053 N push. For load holding, note that a plain SAI cylinder drifts on air loss—the cushion only decelerates—so specify the SAIL or BSAI lock variant, or use an external pilot check valve. Operating speed is 30-500 mm/s.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125BX145S
- ✓ 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 SI125BX145S FAQ
Yes, the AirTAC SI125BX145S is discontinued. The direct replacement is the SAI125BX145S. It shares the identical ISO 15552 mounting interface, 125 mm bore, 145 mm stroke, G1/2 port, and output force, fitting directly into existing fixtures.
This double-acting cylinder features a G1/2 air port and M27x2 rod thread. 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.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125BX145S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125BX145S replacement — usually within 7-8 hours.