This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI63AX250, 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 SI63AX250
The AirTAC Airtac SI63 Standard Cylinder SI63AX250 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 SAI63AX250, 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 → SAI63AX250
- 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 SI63AX250
The AirTAC SI63AX250 is a discontinued double-acting ISO 15552 profile cylinder with a 63 mm bore and 250 mm stroke. It delivers 1559 N push force at 0.5 MPa through a G3/8 port. The direct replacement is the SAI63AX250, which matches the original bore, stroke, force, port and ISO 15552 mounting interface exactly.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. This specific SKU lacks a magnet, so it cannot accept a CS1-B/DS1-B sensor. For load holding, note the cushion only decelerates; use a SAIL lock variant or external check valve.
Airtac SI63 Standard Cylinder SI63AX250 Technical Specifications
| Model | Airtac SI63 Standard Cylinder SI63AX250 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI63AX250 |
| 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 SAI63AX250 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 SAI63AX250 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 SI63AX250
| 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 SI63AX250 Is Used
Clamping Fixtures
Holds medium-duty workpieces securely in machining or welding jigs using its 1559 N push force at 0.5 MPa.
Material Diverters
Actuates routing gates on 63 mm bore assembly lines, with the 250 mm stroke providing full lane-changing reach.
Carton Ejectors
Pushes packaged goods off processing belts, relying on the adjustable 30 mm air cushions to soften end-of-stroke impact.
Replacing the Airtac SI63 Standard Cylinder SI63AX250 with the SAI63AX250
To replace the SI63AX250, order the SAI63AX250. Confirm the ISO 15552 mounting interface, the 63 mm bore, 250 mm stroke, G3/8 port (PT/G/NPT thread) and the SUS420J2 stainless rod. Because this SKU has no -S magnet, it cannot support position sensing. Sizing both ways: the 63 mm bore gives 1559 N push at 0.5 MPa, while the neighbouring 80 mm bore yields 2513 N. At 250 mm stroke, ensure guide alignment to prevent rod bending and side-load wear. The air cushion only decelerates the piston; it will not hold a load on air loss. For secure load holding, specify the SAIL or BSAI lock variant, or fit an external pilot check valve.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI63AX250
- ✓ 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 SI63AX250 FAQ
Yes, the SI63AX250 is discontinued. The direct replacement is the SAI63AX250. It is dimensionally interchangeable per ISO 15552, matching the 63 mm bore, 250 mm stroke, G3/8 port, output force and mounting accessories.
It features a G3/8 air port and provides 1559 N push / 1402 N pull at 0.5 MPa, 2182 N push at 0.7 MPa, 2805 N push at 0.9 MPa, and a theoretical max of 318 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI63AX250
Send us the quantity and destination. We confirm price, stock and lead time on the SAI63AX250 replacement — usually within 7-8 hours.