This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125BX450, 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 SI125BX450
The AirTAC SI125 Standard Cylinder SI125BX450 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 450mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125BX450, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke450 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125BX450
- 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 SI125BX450
The AirTAC SI125BX450 is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 450 mm stroke. It delivers 6136 N push force at 0.5 MPa through a G1/2 port. The direct replacement is the SAI125BX450, matching the bore, stroke, force, port, and ISO 15552 mounting interface.
The SAI upgrade features two Y-shaped one-way piston seals for low start-up pressure. This B-rod variant uses a SUS304 stainless piston rod for corrosion resistance. Without a -S magnet, this SKU cannot take a sensor.
Airtac SI125 Standard Cylinder SI125BX450 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125BX450 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125BX450 |
| Bore size | Ø125 mm |
| Stroke | 450 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 SAI125BX450 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 SAI125BX450 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 SI125BX450
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×450 | 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 SI125BX450 Is Used
Heavy Pressing
Drives large stamping or forming fixtures needing 6136 N of push force at 0.5 MPa.
Pallet Handling
Shifts heavy loaded pallets over 450 mm cycles where the SUS304 rod resists humidity.
Material Ejection
Ejects dense manufactured parts from machinery using a robust 125 mm bore assembly.
Replacing the Airtac SI125 Standard Cylinder SI125BX450 with the SAI125BX450
To replace the SI125BX450, order the SAI125BX450. Verify the ISO 15552 mounting interface, 125 mm bore, 450 mm stroke, G1/2 port, and SUS304 rod. Neighbouring bores: 100 mm gives 3927 N push at 0.5 MPa; 160 mm gives 10053 N. This non-magnetic SKU cannot take CS1-B/DS1-B sensors. For load holding, use an external rod lock or pilot check valve, as cushions only decelerate. At 450 mm, use external guides to prevent rod bending.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125BX450
- ✓ 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 SI125BX450 FAQ
Yes, the SI125BX450 is discontinued. The direct replacement is the SAI125BX450. It is dimensionally interchangeable per ISO 15552, keeping the same 125 mm bore, 450 mm stroke, 6136 N force, and G1/2 port.
This double-acting cylinder has a G1/2 port. It delivers 6136 N push and 5734 N pull at 0.5 MPa, 8590 N push at 0.7 MPa, and a theoretical max of 1251 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125BX450
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125BX450 replacement — usually within 7-8 hours.