This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125BX90, 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 SI125BX90
The AirTAC Airtac SI125 Standard Cylinder SI125BX90 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 90mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125BX90, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke90 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125BX90
- 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 SI125BX90
The AirTAC SI125BX90 is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 90 mm stroke. Built with an extruded aluminium barrel and a SUS304 stainless piston rod, it delivers 6136 N push force at 0.5 MPa through a G1/2 port. The direct replacement is the SAI125BX90, which matches the original ISO 15552 mounting interface, bore, stroke and output force exactly.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and extended life. Because this SKU lacks a magnet (-S), it cannot accept position sensors; legacy SI sensors were CS1-B/DS1-B. Note that a plain cylinder drifts without live air—use the SAIL or BSAI lock variants for load holding.
Airtac SI125 Standard Cylinder SI125BX90 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125BX90 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125BX90 |
| Bore size | Ø125 mm |
| Stroke | 90 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 SAI125BX90 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 SAI125BX90 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 SI125BX90
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×90 | 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 SI125BX90 Is Used
Heavy Stamping Press
Drives heavy tooling in automated stamping lines, using the 6136 N push force to form thick gauge materials reliably.
Injection Mold Clamp
Secures heavy injection molding halves, utilizing the SUS304 stainless rod for corrosion resistance in humid environments.
Replacing the Airtac SI125 Standard Cylinder SI125BX90 with the SAI125BX90
To replace the discontinued SI125BX90, order the SAI125BX90. Confirm the ISO 15552 mounting interface, the 125 mm bore, 90 mm stroke, G1/2 port, and your specific mounting accessory (LB, FA, TC, etc.). The -B rod material denotes SUS304 stainless steel for corrosion resistance. Since this non-magnetic SKU cannot accept a switch, order an -S variant if sensing is required. For sizing both ways: if downsizing to a 100 mm bore, expect 3927 N push at 0.5 MPa; if upsizing to 160 mm, expect 10053 N. Remember that a standard cylinder does not hold load on air loss—use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant for secure holding.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125BX90
- ✓ 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 SI125BX90 FAQ
Yes, the SI125BX90 is discontinued. The direct replacement is the SAI125BX90. It shares the exact same ISO 15552 mounting interface, 125 mm bore, 90 mm stroke, output force, G1/2 port, and SUS304 stainless rod, fitting existing fixtures perfectly.
This 125 mm bore cylinder features a G1/2 air port and M27x2 rod thread. Theoretical forces 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; with a maximum force of 1251 kgf at 1.0 MPa. Operating speed is 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125BX90
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125BX90 replacement — usually within 7-8 hours.