This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI63BX325S, 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 SI63BX325S
The AirTAC Airtac SI63 Standard Cylinder SI63BX325S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø63mm bore and 325mm stroke, G3/8 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI63BX325S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ63 mm
- Stroke325 mm
- Port sizeG3/8
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI63BX325S
- 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 SI63BX325S
The AirTAC SI63BX325S is a discontinued double-acting ISO 15552 profile cylinder with a 63 mm bore and 325 mm stroke. Featuring a SUS304 stainless steel rod and a built-in magnet for legacy CS1-B/DS1-B sensors, it delivers 1559 N push force at 0.5 MPa via a G3/8 port. The direct replacement is the SAI63BX325S, matching the bore, stroke, force, port, and ISO 15552 mounting interface.
The SAI upgrade introduces an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life. The SAI family also adds SAIL, SAIF, and BSAI lock variants absent from the SI line.
Airtac SI63 Standard Cylinder SI63BX325S Technical Specifications
| Model | Airtac SI63 Standard Cylinder SI63BX325S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI63BX325S |
| Bore size | Ø63 mm |
| Stroke | 325 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 SAI63BX325S 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 SAI63BX325S 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 SI63BX325S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 63 | Bore size in mm. |
| ×325 | 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 SI63BX325S Is Used
Stainless Rod Diverters
Ideal for diverting items on packaging lines where the SUS304 rod resists washdown moisture and the 325 mm stroke spans wider belts.
Vertical Lift Gates
Lifts access gates or light barriers using the 79 kg vertical lift margin, safely decelerating at both ends via 30 mm adjustable cushions.
Long-Stroke Press Ejection
Ejects parts from machinery beds where the 325 mm reach is required, relying on external guides to prevent rod bending under side loads.
Replacing the Airtac SI63 Standard Cylinder SI63BX325S with the SAI63BX325S
To replace the SI63BX325S, order the SAI63BX325S and confirm the ISO 15552 mounting interface, 325 mm stroke, G3/8 port, and the -S magnet for current AirTAC switches. The -B code specifies the SUS304 stainless rod for corrosion resistance instead of the default carbon steel. If you need more force, the neighbouring 80 mm bore offers 2513 N push at 0.5 MPa; if less is required, the 50 mm bore provides 982 N. Because this is a 325 mm stroke, use external guides to prevent rod bending and side-load wear. A plain cylinder does not hold load without live air, so for load holding use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI63BX325S
- ✓ 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 SI63BX325S FAQ
Yes, the SI63BX325S is discontinued. The direct replacement is the SAI63BX325S. It is dimensionally interchangeable per the ISO 15552 mounting interface, retaining the same 63 mm bore, 325 mm stroke, G3/8 port, and output force so it fits existing fixtures.
This double-acting cylinder uses a G3/8 air port. The thrust ratings are 1559 N push and 1402 N pull at 0.5 MPa, 2182 N push at 0.7 MPa, 2805 N push at 0.9 MPa, and a theoretical maximum of 318 kgf at 1.0 MPa. It operates at 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI63BX325S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI63BX325S replacement — usually within 7-8 hours.