This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI63AX425, 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 SI63AX425
The AirTAC SI63 Standard Cylinder SI63AX425 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 SAI63AX425, 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 → SAI63AX425
- 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 SI63AX425
The AirTAC SI63AX425 is a discontinued double-acting ISO 15552 profile cylinder with a 63mm bore and 425mm stroke. It delivers 1559N push and 1402N pull at 0.5MPa using a G3/8 port. The direct replacement is the SAI63AX425, which matches the original ISO 15552 mounting interface, bore, stroke, output force, and port size. This SKU features a SUS420J2 stainless steel rod (A suffix) but lacks a magnet, so it cannot accept a position switch.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and long life. If you need load holding on air loss, the plain cylinder drifts since its cushions only decelerate; use an external rod lock or the SAIL/BSAI lock variants.
Airtac SI63 Standard Cylinder SI63AX425 Technical Specifications
| Model | Airtac SI63 Standard Cylinder SI63AX425 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI63AX425 |
| 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 SAI63AX425 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 SAI63AX425 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 SI63AX425
| 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 SI63AX425 Is Used
Material Diversion
Actuates routing gates on package lines, using the 1559N push force at 0.5MPa to deflect heavy cartons reliably.
Pallet Handling
Pushes loaded pallets into stretch-wrap stations, requiring external guides to manage side loads over the 425mm extension.
Replacing the Airtac SI63 Standard Cylinder SI63AX425 with the SAI63AX425
To replace the SI63AX425, order the SAI63AX425. Verify your ISO 15552 mounting accessories (LB, FA, TC, etc.), the G3/8 air port, and the 425mm stroke. Because this non-magnet SKU cannot take a sensor, if position feedback is needed you must order an SAI with the S suffix for CS1-B/DS1-B switches. For sizing, a 50mm bore gives 982N push at 0.5MPa, while an 80mm bore gives 2513N. Note that at 425mm, this cylinder is susceptible to rod bending; use external guides to prevent side loads. For held loads, add a pilot check valve or explore the SAIL lock variant, as standard cushions only decelerate.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI63AX425
- ✓ 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 SI63AX425 FAQ
Yes, the SI63AX425 is discontinued. The direct replacement is the SAI63AX425. It is dimensionally interchangeable per ISO 15552, matching the 63mm bore, 425mm stroke, G3/8 port, and mounting interface. The SAI simply upgrades the piston seal to two Y-shaped elements for lower start-up pressure.
This double-acting cylinder has a 63mm bore, 425mm stroke, 20mm rod, M16x1.5 thread, 30mm cushions, and operates at 30-800mm/s. Force ratings are 1559N push and 1402N pull at 0.5MPa, 2182N push at 0.7MPa, 2805N push at 0.9MPa, and a 318kgf maximum at 1.0MPa. It uses a G3/8 port.
Related AirTAC SAI Cylinders
Request a Quote for the SAI63AX425
Send us the quantity and destination. We confirm price, stock and lead time on the SAI63AX425 replacement — usually within 7-8 hours.