This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125BX800S, 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 SI125BX800S
The AirTAC SI125 Standard Cylinder SI125BX800S 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 SAI125BX800S, 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 → SAI125BX800S
- 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 SI125BX800S
The AirTAC SI125BX800S is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 800 mm stroke. It delivers 6136 N push force at 0.5 MPa, features a SUS304 stainless steel rod, and includes a piston magnet for legacy CS1-B/DS1-B sensors. The direct replacement is the SAI125BX800S, retaining the identical G1/2 port, M27x2 thread, and mounting interface.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and long life. The SAI family also adds SAIL and BSAI lock variants absent in the SI line.
Airtac SI125 Standard Cylinder SI125BX800S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125BX800S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125BX800S |
| 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 SAI125BX800S 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 SAI125BX800S 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 SI125BX800S
| 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 SI125BX800S Is Used
Heavy Press Clamping
Secures large steel plates in a machining fixture, utilizing the 6136 N push force at 0.5 MPa with the SUS304 rod resisting coolant corrosion.
Pallet Diversion
Actuates a heavy-duty diverter arm over an 800 mm travel distance, requiring external guide rails to manage side-load on the extended rod.
Replacing the Airtac SI125 Standard Cylinder SI125BX800S with the SAI125BX800S
To replace the SI125BX800S, order the SAI125BX800S. It is dimensionally interchangeable per ISO 15552, matching the 125 mm bore, 800 mm stroke, G1/2 port, and mounting accessories. Confirm your port thread (PT/G/NPT) and keep the -S magnet for current AirTAC switches. If you need less force, a 100 mm bore provides 3927 N push at 0.5 MPa; if you need more, a 160 mm bore yields 10053 N. At 800 mm stroke, use external guides to prevent rod bending and side-load damage. A plain cylinder drifts on air loss; for load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125BX800S
- ✓ 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 SI125BX800S FAQ
Yes, the AirTAC SI125BX800S is discontinued. The direct replacement is the SAI125BX800S. It is dimensionally interchangeable per ISO 15552, keeping the same 125 mm bore, 800 mm stroke, output force, G1/2 port, and mounting interface, but features an upgraded piston seal.
The G1/2 port and M27x2 rod thread are fixed by the 125 mm bore. 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 max of 1251 kgf at 1.0 MPa. Operating speed is 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125BX800S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125BX800S replacement — usually within 7-8 hours.