This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI63X425, 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 SI63X425
The AirTAC SI63 Standard Cylinder SI63X425 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø63mm bore and 425mm stroke, G3/8 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI63X425, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ63 mm
- Stroke425 mm
- Port sizeG3/8
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI63X425
- 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 SI63X425
The AirTAC SI63X425 is a discontinued double-acting ISO 15552 profile cylinder with a 63 mm bore and 425 mm stroke, delivering 1559 N push force at 0.5 MPa through its G3/8 port. AirTAC replaced this legacy unit with the SAI63X425, a direct upgrade retaining the exact mounting interface, bore, stroke, output force, and port size.
The SAI upgrade features a modernized piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. Note this specific SKU lacks a magnet (-S) and cannot accept position sensors.
Airtac SI63 Standard Cylinder SI63X425 Technical Specifications
| Model | Airtac SI63 Standard Cylinder SI63X425 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI63X425 |
| Bore size | Ø63 mm |
| Stroke | 425 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 SAI63X425 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 SAI63X425 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 SI63X425
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 63 | Bore size in mm. |
| ×425 | 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 SI63X425 Is Used
Material Diversion
Drives diverter gates on package lines, using the 1559 N thrust to push heavy cartons smoothly at 30-800 mm/s.
Vertical Pressing
Applies downward clamping pressure in light assembly jigs, safely handling loads near the 79 kg vertical lift threshold.
Pallet Handling
Actuates stoppers and indexing mechanisms in pallet flow systems, relying on the 425 mm stroke to clear passing loads.
Replacing the Airtac SI63 Standard Cylinder SI63X425 with the SAI63X425
To replace the SI63X425, order the SAI63X425. Verify your ISO 15552 mounting accessory (LB, FA, CA, TC, etc.), the G3/8 air port thread (PT, G, or NPT), and the M16x1.5 rod-end connection. Because this is a non-magnetized SKU, it cannot support legacy CS1-B/DS1-B sensors; if sensing is required, specify an SAI model with the -S magnet option. Sizing context: a 63 mm bore yields 1559 N push at 0.5 MPa; dropping to a 50 mm bore gives 982 N, while stepping up to an 80 mm bore provides 2513 N. A standard cylinder drifts on air loss—the cushion only decelerates—so for load holding, consider the SAIL or BSAI lock variants, or an external pilot check valve. Finally, at 425 mm, the stroke demands attention to side-load and rod-bending; use external guides to prevent premature wear.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI63X425
- ✓ 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 SI63X425 FAQ
Yes, the SI63X425 is discontinued. The direct replacement is the AirTAC SAI63X425. It shares the identical ISO 15552 mounting interface, 63 mm bore, 425 mm stroke, output force, and G3/8 port, fitting directly into existing fixtures.
This 63 mm bore cylinder uses a G3/8 air port. It generates 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.
Request a Quote for the SAI63X425
Send us the quantity and destination. We confirm price, stock and lead time on the SAI63X425 replacement — usually within 7-8 hours.