This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI63X420STC, 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 SI63X420STC
The AirTAC SI63 Standard Cylinder SI63X420STC is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø63mm bore and 420mm stroke, G3/8 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI63X420STC, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ63 mm
- Stroke420 mm
- Port sizeG3/8
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI63X420STC
- 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 SI63X420STC
The AirTAC SI63X420STC is a discontinued double-acting ISO 15552 profile cylinder with a 63 mm bore and 420 mm stroke. It delivers 1559 N push force at 0.5 MPa through a G3/8 port. AirTAC replaced this legacy unit with the SAI63X420STC, a direct alternative retaining the exact ISO 15552 mounting interface, bore, stroke, output force, port size and TC trunnion mount.
The SAI upgrade features a refined piston seal using two Y-shaped one-way elements for low start-up pressure and extended life. The SAI family also introduces SAIL, SAIF and BSAI lock variants absent in the SI line. The -S magnet supports CS1-B/DS1-B sensors, while a Viton H seal option raises operating temperatures to 150 C.
Airtac SI63 Standard Cylinder SI63X420STC Technical Specifications
| Model | Airtac SI63 Standard Cylinder SI63X420STC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI63X420STC |
| Bore size | Ø63 mm |
| Stroke | 420 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 SAI63X420STC 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 SAI63X420STC 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 SI63X420STC
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 63 | Bore size in mm. |
| ×420 | 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 SI63X420STC Is Used
Material Diversion
Actuates routing gates on package conveyors where the 1559 N push force and 420 mm travel easily clear wider product profiles.
Vertical Lowering
Lowers 79 kg work platforms through 420 mm; external guides are recommended to absorb side loads during the descent.
Pallet Handling
Pushes pallets into staging lanes using the TC trunnion mount to accommodate angular alignment over the long stroke.
Replacing the Airtac SI63 Standard Cylinder SI63X420STC with the SAI63X420STC
To replace the SI63X420STC, order the SAI63X420STC. Confirm the ISO 15552 TC trunnion mounting interface, 63 mm bore, 420 mm stroke, G3/8 port (PT/G/NPT thread options) and the -S magnet for legacy CS1-B/DS1-B switches. Sizing checks: a 50 mm bore yields 982 N push at 0.5 MPa, whereas an 80 mm bore provides 2513 N. Because this is a 420 mm stroke, use external guides to prevent rod bending and side-load damage. A plain cylinder drifts on air loss since cushions only decelerate; for load holding, specify the SAIL or BSAI lock variant, or an external pilot check valve.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI63X420STC
- ✓ 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 SI63X420STC FAQ
Yes, the SI63X420STC is discontinued. The direct replacement is the SAI63X420STC. It shares the identical ISO 15552 mounting interface, 63 mm bore, 420 mm stroke, output force, G3/8 port and TC trunnion mount, fitting directly into existing fixtures.
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 maximum of 318 kgf at 1.0 MPa. The unit operates at 30-800 mm/s with a 20 mm rod and M16x1.5 thread.
Related AirTAC SAI Cylinders
Request a Quote for the SAI63X420STC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI63X420STC replacement — usually within 7-8 hours.