This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI63BX425, 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 SI63BX425
The AirTAC Airtac SI63 Standard Cylinder SI63BX425 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 SAI63BX425, 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 → SAI63BX425
- 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 SI63BX425
The AirTAC SI63BX425 is a discontinued double-acting ISO 15552 profile cylinder with a 63mm bore and 425mm stroke. It delivers 1559 N push force at 0.5 MPa via a G3/8 port. The direct replacement is the SAI63BX425, sharing the same ISO 15552 mounting interface, stroke, force and porting to fit existing fixtures seamlessly.
This SKU features a SUS304 stainless steel rod for corrosion resistance, but lacks a magnet so it cannot accept position switches. The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure.
Airtac SI63 Standard Cylinder SI63BX425 Technical Specifications
| Model | Airtac SI63 Standard Cylinder SI63BX425 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI63BX425 |
| 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 SAI63BX425 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 SAI63BX425 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 SI63BX425
| 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 SI63BX425 Is Used
Stainless Rod Actuation
Ideal for machinery requiring corrosion resistance, utilizing the SUS304 piston rod to drive 1559 N loads in humid or washdown environments.
Extended Stroke Diverting
The 425mm stroke handles long-travel diverting or sorting gates on packaging lines, moving products reliably at 30-800 mm/s.
Replacing the Airtac SI63 Standard Cylinder SI63BX425 with the SAI63BX425
To replace the SI63BX425, order the SAI63BX425. Confirm the ISO 15552 mounting interface (LB, FA, TC, etc.), the 425mm stroke, G3/8 port and the SUS304 rod option. Because this is a no-S SKU, it cannot take a sensor; if sensing is needed, use an external switch. At 425mm, prevent rod bending by guiding the load externally. A plain cylinder drifts on air loss; for load holding use an external pilot check valve or the SAIL/BSAI lock variants. Neighbouring bores: 50mm gives 982 N [email protected], while 80mm gives 2513 N.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI63BX425
- ✓ 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 SI63BX425 FAQ
Yes, the SI63BX425 is discontinued. The direct replacement is the SAI63BX425. It is dimensionally interchangeable per ISO 15552, retaining the same 63mm bore, 425mm stroke, output force, G3/8 port and mounting accessories.
The G3/8 port feeds a 20mm rod delivering 1559 N push and 1402 N pull 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 SAI63BX425
Send us the quantity and destination. We confirm price, stock and lead time on the SAI63BX425 replacement — usually within 7-8 hours.