This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125BX800, 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 SI125BX800
The AirTAC SI125 Standard Cylinder SI125BX800 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 800mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125BX800, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke800 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125BX800
- 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 SI125BX800
The AirTAC SI125BX800 is a discontinued double-acting ISO 15552 profile cylinder featuring a 125 mm bore, 800 mm stroke, and a SUS304 stainless steel piston rod. Generating 6136 N push force at 0.5 MPa, it is replaced by the SAI125BX800. This direct successor shares the exact ISO 15552 mounting interface, G1/2 port, and output force, fitting existing fixtures perfectly.
The SAI125BX800 upgrades the piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. Because this SKU lacks a magnet (-S), it cannot accept position sensors. Note that a plain cylinder drifts on air loss; for load holding, consider the SAIL or BSAI lock variants.
Airtac SI125 Standard Cylinder SI125BX800 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125BX800 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125BX800 |
| Bore size | Ø125 mm |
| Stroke | 800 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 SAI125BX800 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 SAI125BX800 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 SI125BX800
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×800 | 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 SI125BX800 Is Used
Heavy Press Ejection
Provides the 6136 N push force needed to eject dense stamped metal parts from heavy press dies, with the 800 mm stroke clearing the machine bed entirely.
Pallet Discharge
Handles the extended 800 mm reach to push loaded pallets off high-throughput roller conveyors, utilizing the SUS304 rod for washdown corrosion resistance.
Material Lift Lowering
Deposits heavy material stacks using controlled air cushions, though an external pilot check valve must be fitted to prevent drifting if air pressure drops mid-descent.
Replacing the Airtac SI125 Standard Cylinder SI125BX800 with the SAI125BX800
To replace the SI125BX800, order the SAI125BX800, confirming the ISO 15552 interface, 800 mm stroke, G1/2 port, and SUS304 rod (-B). Since this non-magnetic SKU lacks a sensor groove switch, you cannot use CS1-B/DS1-B sensors; if sensing is needed, switch to an SAI125X800S. For sizing, the 125 mm bore yields 6136 N push at 0.5 MPa; dropping to a 100 mm bore reduces force to 3927 N, while a 160 mm bore increases it to 10053 N. At 800 mm, side-load and rod-bending risks are high, so use external guides to prevent premature seal wear. A plain cylinder does not hold load without live air—the cushion only decelerates—so use an external rod lock or pilot check valve for safety, or specify a SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125BX800
- ✓ 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 SI125BX800 FAQ
Yes, the SI125BX800 is discontinued. The direct replacement is the SAI125BX800. It is dimensionally interchangeable per ISO 15552, retaining the same 125 mm bore, 800 mm stroke, G1/2 port, and mounting interface, so it drops directly into existing fixtures.
The bore is 125 mm with a G1/2 air port. At 0.5 MPa it provides 6136 N push and 5734 N pull force. At 0.7 MPa push is 8590 N, and at 0.9 MPa it is 11045 N. The theoretical maximum force is 1251 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125BX800
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125BX800 replacement — usually within 7-8 hours.