This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI63X125SFTC, 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 SI63X125SFTC
The AirTAC Airtac SI63 Standard Cylinder SI63X125SFTC is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø63mm bore and 125mm stroke, G3/8 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI63X125SFTC, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ63 mm
- Stroke125 mm
- Port sizeG3/8
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI63X125SFTC
- 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 SI63X125SFTC
The AirTAC SI63X125SFTC is a discontinued double-acting ISO 15552 profile cylinder featuring a 63 mm bore, 125 mm stroke, and an FTC trunnion mount. Built with an extruded aluminum barrel and adjustable air cushions at both ends, it delivers a thrust of 1559 N at 0.5 MPa. It includes a piston magnet for position sensing. The direct replacement is the SAI63X125SFTC, which preserves the exact ISO 15552 mounting interface, G3/8 port size, M16x1.5 rod thread, and output force.
The SAI upgrade introduces an improved piston seal utilizing two Y-shaped one-way elements for extended lifespan and lower start-up pressure. The SAI family also expands functionality with SAIL, SAIF, and BSAI lock variants absent in the legacy SI line. The original -S magnet configuration supports CS1-B/DS1-B switches, while the SAI successor uses current AirTAC sensors.
Airtac SI63 Standard Cylinder SI63X125SFTC Technical Specifications
| Model | Airtac SI63 Standard Cylinder SI63X125SFTC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI63X125SFTC |
| Bore size | Ø63 mm |
| Stroke | 125 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 SAI63X125SFTC 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 SAI63X125SFTC 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 SI63X125SFTC
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 63 | Bore size in mm. |
| ×125 | 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 SI63X125SFTC Is Used
Mid-Tonnage Pressing
Applies the 1559 N push force at 0.5 MPa for seating bearings, stamping light sheet metal, or assembling pinned components in automated machinery.
Package Diversion
Uses the 125 mm stroke and FTC trunnion mount to actuate routing gates or pusher arms, redirecting mid-weight cartons on packaging lines.
Replacing the Airtac SI63 Standard Cylinder SI63X125SFTC with the SAI63X125SFTC
To replace the discontinued SI63X125SFTC, order the SAI63X125SFTC. Verify your existing fixture's ISO 15552 trunnion (FTC) mounting dimensions, 125 mm stroke, and G3/8 port thread (available in PT, G, or NPT). The 63 mm bore yields 1559 N push and 1402 N pull at 0.5 MPa; if you need less force, step down to a 50 mm bore (982 N push), or step up to an 80 mm bore (2513 N push) for heavier loads. Because this is a double-acting cylinder, it will not hold a load if air pressure drops—the cushions only decelerate the piston near stroke end. For secure load holding, consider an external pilot check valve, a rod lock, or the SAIL/BSAI locking variants. The standard 30 mm cushion stroke ensures smooth deceleration within the 30-800 mm/s speed range. Rod material options include carbon steel, SUS420J2 (A), or SUS304 (B).
Replacement checklist
- ✓ Same ISO 15552 interface → SAI63X125SFTC
- ✓ 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 SI63X125SFTC FAQ
Yes, the SI63X125SFTC is discontinued. The direct replacement is the AirTAC SAI63X125SFTC. It features the same ISO 15552 mounting interface, 63 mm bore, 125 mm stroke, G3/8 port, and output force, fitting directly into existing FTC trunnion fixtures.
The 63 mm bore cylinder uses a G3/8 air port and a M16x1.5 rod thread. Force output is 1559 N push and 1402 N pull at 0.5 MPa, 2182 N push at 0.7 MPa, 2805 N push at 0.9 MPa, and a theoretical maximum of 318 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI63X125SFTC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI63X125SFTC replacement — usually within 7-8 hours.