This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125BX125SH, 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 SI125BX125SH
The AirTAC SI125 Standard Cylinder SI125BX125SH is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 125mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125BX125SH, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke125 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125BX125SH
- 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 SI125BX125SH
The AirTAC SI125BX125SH is a discontinued double-acting ISO 15552 profile cylinder with a 125mm bore and 125mm stroke. Built for heavy-duty thrust, it delivers 6136N push force at 0.5MPa. The direct replacement is the SAI125BX125SH, maintaining the identical ISO 15552 mounting interface, G1/2 port, and M27x2 rod thread. This specific configuration includes a SUS304 stainless steel rod (-B) for corrosion resistance, a high-temperature Viton H seal (-H rated for 0-150C), and a piston magnet (-S) for legacy CS1-B/DS1-B sensors.
Upgrading to the SAI125BX125SH introduces an advanced two Y-shaped one-way piston seal for low start-up pressure and extended life. The SAI family also adds SAIL, SAIF, and BSAI lock variants absent in the legacy SI line.
Airtac SI125 Standard Cylinder SI125BX125SH Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125BX125SH |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125BX125SH |
| Bore size | Ø125 mm |
| Stroke | 125 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 SAI125BX125SH 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 SAI125BX125SH 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 SI125BX125SH
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×125 | 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 SI125BX125SH Is Used
Heavy Stamping Press
Drives large dies and heavy press tooling where the 6136N thrust at 0.5MPa and robust 32mm rod withstand high impact forces.
High-Tact Forming
Operates in heated forming environments using the Viton H seal up to 150C, while the SUS304 rod resists corrosive off-gassing.
Replacing the Airtac SI125 Standard Cylinder SI125BX125SH with the SAI125BX125SH
To replace the SI125BX125SH, order the SAI125BX125SH. It is a direct per ISO 15552 mounting dimensions, keeping the 125mm stroke, G1/2 port, and 1251kgf maximum force. Retain your mounting accessories and confirm the -B stainless rod and -H Viton seal options. If sizing down, a 100mm bore yields 3927N push at 0.5MPa; if sizing up, a 160mm bore provides 10053N. Because this is a 125mm bore, speed is 30-500mm/s. Note that a standard cylinder drifts without live air—the cushion only decelerates end-of-stroke. For load holding, use an external pilot check valve or the SAIL/BSAI lock variant. The -S magnet works with CS1-B/DS1-B switches; the SAI uses current AirTAC switches.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125BX125SH
- ✓ 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 SI125BX125SH FAQ
Yes, the SI series is discontinued. The direct replacement is the SAI125BX125SH. It is dimensionally interchangeable per ISO 15552, keeping the same 125mm bore, 125mm stroke, G1/2 port, and mounting interface.
It features a G1/2 air port. The thrust ratings are 6136N push and 5734N pull at 0.5MPa, 8590N push at 0.7MPa, 11045N push at 0.9MPa, and a theoretical maximum of 1251kgf at 1.0MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125BX125SH
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125BX125SH replacement — usually within 7-8 hours.