This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125BX85, 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 SI125BX85
The AirTAC Airtac SI125 Standard Cylinder SI125BX85 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 85mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125BX85, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke85 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125BX85
- 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 SI125BX85
The AirTAC SI125BX85 is a discontinued double-acting ISO 15552 profile cylinder with a 125mm bore and 85mm stroke. It delivers 6136N push and 5734N pull at 0.5MPa, peaking at 1251kgf. The direct replacement is the SAI125BX85, matching the G1/2 port, M27x2 thread, and ISO 15552 mounting interface. This SKU has a SUS304 stainless rod (-B) but no magnet, so it cannot take a sensor.
The SAI upgrade features two Y-shaped one-way piston seals for low start-up pressure and long life. For load holding, note the cushion only decelerates; explore the SAIL lock or BSAI clamp-lock variants the SI lacked.
Airtac SI125 Standard Cylinder SI125BX85 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125BX85 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125BX85 |
| Bore size | Ø125 mm |
| Stroke | 85 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 SAI125BX85 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 SAI125BX85 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 SI125BX85
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×85 | 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 SI125BX85 Is Used
Heavy Press Clamping
Secures large steel plates in a hydraulic press fixture, utilizing the 6136N push force and SUS304 rod to resist corrosion from cutting fluids.
Pallet Diversion
Pushes heavy loaded pallets onto a secondary packaging line, relying on the 85mm stroke and 1251kgf maximum theoretical force for reliable lateral shifts.
Replacing the Airtac SI125 Standard Cylinder SI125BX85 with the SAI125BX85
To replace the SI125BX85, order the SAI125BX85. Verify the ISO 15552 interface, 85mm stroke, G1/2 port, and SUS304 rod. Since this SKU lacks -S, it cannot accept CS1-B/DS1-B sensors. Sizing both ways: a 100mm bore gives 3927N push at 0.5MPa, while a 160mm bore yields 10053N. The 125mm bore operates at 30-500mm/s. Because it is double-acting, it needs live air; the cushion only decelerates, so for holding loads use an external pilot check valve or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125BX85
- ✓ 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 SI125BX85 FAQ
Yes, the AirTAC SI125BX85 is discontinued. The direct replacement is the SAI125BX85. It shares the same ISO 15552 mounting interface, 125mm bore, 85mm stroke, G1/2 port, and SUS304 rod, fitting existing fixtures perfectly.
This double-acting cylinder has a G1/2 port. It delivers 6136N push and 5734N pull at 0.5MPa, 8590N push at 0.7MPa, 11045N push at 0.9MPa, and a maximum theoretical force of 1251kgf at 1.0MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125BX85
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125BX85 replacement — usually within 7-8 hours.