This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI63X125SFA, 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 SI63X125SFA
The AirTAC Airtac SI63 Standard Cylinder SI63X125SFA 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 SAI63X125SFA, 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 → SAI63X125SFA
- 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 SI63X125SFA
The AirTAC SI63X125SFA is a discontinued double-acting ISO 15552 profile cylinder with a 63 mm bore and 125 mm stroke. It delivers 1559 N push force at 0.5 MPa through a G3/8 port. AirTAC replaced this legacy unit with the SAI63X125SFA, a direct upgrade retaining the exact ISO 15552 mounting interface, bore, stroke, force and FA flange mounting.
The SAI replacement features 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 the SI lacked. Your -S suffix means a piston magnet for CS1-B/DS1-B switches; the SAI uses current AirTAC switches.
Airtac SI63 Standard Cylinder SI63X125SFA Technical Specifications
| Model | Airtac SI63 Standard Cylinder SI63X125SFA |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI63X125SFA |
| 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 SAI63X125SFA 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 SAI63X125SFA 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 SI63X125SFA
| 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 SI63X125SFA Is Used
Clamp Actuation
Provides 1559 N of secure clamping force at 0.5 MPa for holding medium-weight machined parts during milling or drilling operations.
Package Diversion
Uses the 125 mm stroke to extend a diverter arm, routing heavy cartons on a packaging line with rapid 30-800 mm/s cycling.
Pallet Stopping
Acts as a robust pneumatic stop gate for loaded pallets, utilizing the FA flange mount to absorb repeated horizontal impacts.
Replacing the Airtac SI63 Standard Cylinder SI63X125SFA with the SAI63X125SFA
To replace the SI63X125SFA, order the SAI63X125SFA. Confirm the ISO 15552 interface, 63 mm bore, 125 mm stroke, G3/8 port (PT/G/NPT thread options), FA flange mounting, and the -S magnet. Sizing both ways: a 50 mm bore yields 982 N push at 0.5 MPa, while an 80 mm bore yields 2513 N. This plain cylinder does not hold load without live air; the cushion only decelerates. For load holding on air loss, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant. Stroke is under 300 mm so rod bending is minimal, but ensure FA flange alignment to prevent side-load wear.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI63X125SFA
- ✓ 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 SI63X125SFA FAQ
Yes, the SI63X125SFA is discontinued. The direct replacement is the SAI63X125SFA. It shares the identical ISO 15552 mounting interface, 63 mm bore, 125 mm stroke, force output, G3/8 port and FA flange, fitting directly into existing fixtures.
The 63 mm bore uses a G3/8 air port and M16x1.5 rod thread. Force output is 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, with a theoretical maximum of 318 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI63X125SFA
Send us the quantity and destination. We confirm price, stock and lead time on the SAI63X125SFA replacement — usually within 7-8 hours.