This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI63BX250, 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 SI63BX250
The AirTAC Airtac SI63 Standard Cylinder SI63BX250 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø63mm bore and 250mm stroke, G3/8 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI63BX250, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ63 mm
- Stroke250 mm
- Port sizeG3/8
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI63BX250
- 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 SI63BX250
The AirTAC SI63BX250 is a discontinued double-acting ISO 15552 profile cylinder with a 63mm bore, 250mm stroke, and a SUS304 stainless steel rod. Delivering 1559 N push force at 0.5 MPa, it is replaced by the SAI63BX250. This direct successor shares the exact ISO 15552 mounting interface, G3/8 port, and output force, fitting existing fixtures perfectly.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. Note this SKU lacks a magnet and cannot take a sensor; the SAI family adds SAIL and BSAI lock variants absent from the SI line.
Airtac SI63 Standard Cylinder SI63BX250 Technical Specifications
| Model | Airtac SI63 Standard Cylinder SI63BX250 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI63BX250 |
| Bore size | Ø63 mm |
| Stroke | 250 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 SAI63BX250 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 SAI63BX250 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 SI63BX250
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 63 | Bore size in mm. |
| ×250 | 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 SI63BX250 Is Used
Stainless Rod Actuation
Ideal for packaging machinery requiring the SUS304 corrosion-resistant rod option to withstand washdown environments while delivering 1559 N push force.
Material Diversion
Provides robust 250mm stroke diversion gates in conveying systems, utilizing the adjustable 30mm air cushions to decelerate loads smoothly at cycle end.
Replacing the Airtac SI63 Standard Cylinder SI63BX250 with the SAI63BX250
To replace the SI63BX250, order the SAI63BX250 direct: it matches the ISO 15552 interface, 63mm bore, 250mm stroke, G3/8 port, and SUS304 rod. Because this specific SKU has no magnet (-S), it cannot accept CS1-B/DS1-B sensors. For sizing, a 50mm bore yields 982 N push at 0.5 MPa, while an 80mm bore yields 2513 N. The cushion only decelerates; it does not hold load. For static holding on air loss, use an external pilot check valve or the SAIL/BSAI lock variants. At 250mm stroke, ensure guide alignment to prevent rod bending side-loads.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI63BX250
- ✓ 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 SI63BX250 FAQ
Yes, the SI63BX250 is discontinued. The direct replacement is the SAI63BX250. It shares the same ISO 15552 mounting interface, 63mm bore, 250mm stroke, output force, and G3/8 port, fitting directly into existing fixtures.
The 63mm bore features a G3/8 air port. It delivers 1559 N push and 1402 N pull at 0.5 MPa, 2182 N push at 0.7 MPa, and a theoretical max of 318 kgf at 1.0 MPa. The rod is 20mm with an M16x1.5 thread.
Related AirTAC SAI Cylinders
Request a Quote for the SAI63BX250
Send us the quantity and destination. We confirm price, stock and lead time on the SAI63BX250 replacement — usually within 7-8 hours.