This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI63X250SFA, 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 SI63X250SFA
The AirTAC Airtac SI63 Standard Cylinder SI63X250SFA 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 SAI63X250SFA, 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 → SAI63X250SFA
- 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 SI63X250SFA
The AirTAC SI63X250SFA is a discontinued double-acting ISO 15552 profile cylinder with a 63mm bore and 250mm stroke. Delivering 1559N push force at 0.5MPa via a G3/8 port, it is directly replaced by the SAI63X250SFA. This direct upgrade shares the exact same ISO 15552 mounting interface, FA flange, and M16x1.5 rod thread.
The SAI upgrade features a modernized piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. The original SI includes a magnet for CS1-B/DS1-B sensors, while the SAI family expands capabilities with SAIL, SAIF, and BSAI lock variants.
Airtac SI63 Standard Cylinder SI63X250SFA Technical Specifications
| Model | Airtac SI63 Standard Cylinder SI63X250SFA |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI63X250SFA |
| 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 SAI63X250SFA 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 SAI63X250SFA 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 SI63X250SFA
| 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 SI63X250SFA Is Used
Clamp Actuation
Provides 1559N of secure clamping force for machining fixtures, utilizing the FA flange to hold rigid against vibration.
Package Diverting
Drives 250mm stroke diverter arms on sorting lines, moving moderate loads with a safe working capacity near 935N.
Replacing the Airtac SI63 Standard Cylinder SI63X250SFA with the SAI63X250SFA
To replace the SI63X250SFA, order the SAI63X250SFA. Confirm the ISO 15552 FA flange interface, 63mm bore, 250mm stroke, G3/8 port, and the -S magnet for current AirTAC switches. For sizing, a 50mm bore gives 982N push at 0.5MPa, while an 80mm bore yields 2513N. Note that a plain cylinder drifts on air loss; the air cushion only decelerates near stroke ends. For load holding, use an external pilot check valve or the SAIL/BSAI lock variant. At 250mm stroke, verify guide alignment to prevent rod bending side-loads.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI63X250SFA
- ✓ 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 SI63X250SFA FAQ
Yes, the SI63X250SFA is discontinued. The direct replacement is the SAI63X250SFA. It is dimensionally interchangeable per ISO 15552, retaining the same 63mm bore, 250mm stroke, G3/8 port, FA flange mount, and M16x1.5 rod thread.
The 63mm bore features a G3/8 air port and provides 1559N push / 1402N pull at 0.5MPa, 2182N push at 0.7MPa, 2805N at 0.9MPa, and a maximum theoretical force of 318kgf at 1.0MPa. It operates at 30-800mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI63X250SFA
Send us the quantity and destination. We confirm price, stock and lead time on the SAI63X250SFA replacement — usually within 7-8 hours.