This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125BX10S, 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 SI125BX10S
The AirTAC SI125 Standard Cylinder SI125BX10S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 10mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125BX10S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke10 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125BX10S
- 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 SI125BX10S
The AirTAC SI125BX10S is a discontinued double-acting ISO 15552 profile cylinder featuring a SUS304 stainless piston rod and a built-in magnet. Delivering 6136 N push force at 0.5 MPa, it is replaced by the SAI125BX10S. This direct upgrade retains the exact 125 mm bore, 10 mm stroke, G1/2 port, and ISO 15552 mounting interface. The SAI features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure.
The standard cushion is 40 mm, though this 10 mm stroke operates within the 30-500 mm/s range. The -S magnet supports legacy CS1-B/DS1-B sensors, while the SAI family adds SAIL, SAIF, and BSAI lock variants the SI lacked.
Airtac SI125 Standard Cylinder SI125BX10S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125BX10S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125BX10S |
| Bore size | Ø125 mm |
| Stroke | 10 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 SAI125BX10S 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 SAI125BX10S 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 SI125BX10S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×10 | 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 SI125BX10S Is Used
High-Force Clamping
Secures heavy steel plates in machining fixtures using 6136 N of thrust at 0.5 MPa, with the SUS304 rod resisting coolant corrosion.
Short-Stroke Ejection
Provides a rapid 10 mm ejection punch for thick molded parts, operating reliably at speeds between 30 and 500 mm/s.
Pallet Stopping
Acts as a robust high-force stop gate for heavy pallets on conveyor lines, dropping directly into existing ISO 15552 mounts.
Replacing the Airtac SI125 Standard Cylinder SI125BX10S with the SAI125BX10S
To replace the SI125BX10S, order the SAI125BX10S. Confirm the ISO 15552 mounting interface, the G1/2 port, the SUS304 stainless rod (-B), and the magnet (-S) for current AirTAC switches. When sizing, note the 125 mm bore yields 6136 N push at 0.5 MPa; a smaller 100 mm bore provides 3927 N, while this cylinder maxes out at 1251 kgf at 1.0 MPa. A plain cylinder does not hold load without live air; the cushion only decelerates. For load holding on air loss, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant. Because the 10 mm stroke is very short, verify internal cushion adjustment to prevent end-cap impact.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125BX10S
- ✓ 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 SI125BX10S FAQ
Yes, the SI125BX10S is discontinued. The direct replacement is the SAI125BX10S. It shares the same ISO 15552 mounting interface, 125 mm bore, 10 mm stroke, output force, G1/2 port, and SUS304 rod. You simply order the SAI equivalent for your existing fixtures.
This 125 mm bore cylinder has a G1/2 air port. It generates 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 force of 1251 kgf at 1.0 MPa. It operates at 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125BX10S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125BX10S replacement — usually within 7-8 hours.