This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI63BX125S, 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 SI63 Standard Cylinder SI63BX125S
The AirTAC Airtac SI63 Standard Cylinder SI63BX125S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø63mm bore and 125mm stroke, G3/8 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI63BX125S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ63 mm
- Stroke125 mm
- Port sizeG3/8
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI63BX125S
- 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 SI63 Standard Cylinder SI63BX125S
The AirTAC SI63BX125S is a discontinued double-acting ISO 15552 profile cylinder with a 63 mm bore and 125 mm stroke. It features a SUS304 stainless piston rod (-B) and a built-in magnet (-S) for legacy CS1-B/DS1-B switches. Delivering 1559 N push at 0.5 MPa through a G3/8 port, its direct replacement is the SAI63BX125S, which shares the exact ISO 15552 mounting interface, force, and stroke.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and extended life. The SAI family also adds SAIL, SAIF, and BSAI lock variants absent in the SI line.
Airtac SI63 Standard Cylinder SI63BX125S Technical Specifications
| Model | Airtac SI63 Standard Cylinder SI63BX125S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI63BX125S |
| Bore size | Ø63 mm |
| Stroke | 125 mm |
| Acting type | Double acting |
| Port size | G3/8 |
| Rod thread | M16×1.5 |
| 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 – 800 mm/s |
| Cushion | Adjustable, 30 mm |
| Max standard stroke | Up to 1500 mm |
Specifications follow the official AirTAC SI datasheet (now discontinued). The SAI63BX125S carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
Theoretical Output Force (Ø63mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 1559 N | 1402 N |
| 0.7 MPa | 2182 N | — |
| Max (@1.0 MPa) | 318 kgf | |
The SAI63BX125S produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SI63 Standard Cylinder SI63BX125S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 63 | Bore size in mm. |
| ×125 | 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 SI63 Standard Cylinder SI63BX125S Is Used
Stainless Rod Actuation
Leverages the SUS304 rod for corrosion-resistant pushing in washdown or mildly chemical manufacturing environments.
Mid-Range Transfer Diverting
Provides robust 1559 N force at 0.5 MPa to push heavy pallets or products smoothly between conveyor lanes.
Replacing the Airtac SI63 Standard Cylinder SI63BX125S with the SAI63BX125S
To replace the SI63BX125S, order the SAI63BX125S. Confirm the ISO 15552 interface, 63 mm bore, 125 mm stroke, G3/8 port, M16x1.5 rod thread, and SUS304 rod. The -S magnet allows current AirTAC switches to replace the legacy CS1-B/DS1-B sensors. Sizing both ways: a 50 mm bore yields 982 N push at 0.5 MPa, while an 80 mm bore yields 2513 N. Note that a plain cylinder drifts without live air; for load holding, use an external pilot check valve or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI63BX125S
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SI63 Standard Cylinder SI63BX125S FAQ
Yes, the SI63BX125S is discontinued. The direct replacement is the SAI63BX125S. It shares the identical ISO 15552 mounting interface, 63 mm bore, 125 mm stroke, output force, G3/8 port, and mounting accessories, fitting directly into existing fixtures.
The G3/8 port bore delivers a push force of 1559 N and pull of 1402 N at 0.5 MPa. At 0.7 MPa push is 2182 N, and 2805 N at 0.9 MPa. The theoretical maximum force is 318 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI63BX125S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI63BX125S replacement — usually within 7-8 hours.