This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125BX105S, 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 SI125BX105S
The AirTAC SI125 Standard Cylinder SI125BX105S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 105mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125BX105S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke105 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125BX105S
- 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 SI125BX105S
The AirTAC SI125BX105S is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore, 105 mm stroke, and a SUS304 stainless piston rod (-B). Delivering 6136 N push force at 0.5 MPa, it is replaced by the direct replacement SAI125BX105S, which shares the exact bore, stroke, G1/2 port, and ISO 15552 mounting interface. The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life.
This -S model includes a piston magnet for legacy CS1-B/DS1-B sensors. Note that a plain cylinder drifts on air loss; for load holding, use an external rod lock or the SAIL/BSAI lock variants.
Airtac SI125 Standard Cylinder SI125BX105S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125BX105S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125BX105S |
| Bore size | Ø125 mm |
| Stroke | 105 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 SAI125BX105S 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 SAI125BX105S 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 SI125BX105S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×105 | 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 SI125BX105S Is Used
Heavy-Duty Pressing
Drives large stamps and forming tools with 6136 N thrust at 0.5 MPa, using the SUS304 rod in corrosive washdown environments.
Automated Clamping
Secures large workpieces during machining, relying on adjustable 40 mm air cushions to decelerate the 32 mm rod at stroke ends.
Replacing the Airtac SI125 Standard Cylinder SI125BX105S with the SAI125BX105S
To replace the SI125BX105S, order the SAI125BX105S. Confirm the ISO 15552 mounting interface, the 105 mm stroke, the G1/2 port (PT/G/NPT thread options), and the -S magnet for current AirTAC switch compatibility. If you need a different force class, neighbor bores are 100 mm (3927 N push @0.5 MPa) and 160 mm (10053 N push @0.5 MPa). The 32 mm rod uses an M27x2 thread. Because this is a plain double-acting cylinder, it cannot hold a load without live air—the 40 mm cushions only decelerate. For load holding, specify the SAIL air-released lock or BSAI clamp-lock variant, or add a pilot check valve. The -B rod is SUS304 stainless steel; a Viton H seal option extends temperature limits to 0-150 C.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125BX105S
- ✓ 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 SI125BX105S FAQ
Yes, the AirTAC SI125BX105S is discontinued. The direct replacement is the SAI125BX105S. It features the same ISO 15552 mounting interface, 125 mm bore, 105 mm stroke, output force, and G1/2 port, fitting existing fixtures perfectly while upgrading the piston seal.
The 125 mm bore uses a G1/2 port with a 32 mm rod (M27x2 thread). 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. Operating speed is 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125BX105S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125BX105S replacement — usually within 7-8 hours.