This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAIJ63X450-75, 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.

The AirTAC SIJ63 Double Rod Adjustable Cylinder SIJ63X450-75 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø63mm bore and 450mm stroke, G3/8 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAIJ63X450-75, which matches its ISO interface, bore, stroke, force and mounting.
The AirTAC SIJ63X450-75 is a discontinued double-acting double-rod ISO 15552 adjustable-stroke cylinder with a 63mm bore, 450mm nominal stroke, and a G3/8 port. An external stop screw lets you trim the extend stroke by up to 75mm on-site, yielding a usable extend range of 375-450mm. The stop sets the end position; it is not a load lock.
The direct replacement is the SAIJ63X450-75, retaining the same interface, force, and adjust window. The SAIJ family uses an upgraded two Y-shaped one-way piston seal for low start-up pressure and long life. This non-magnetic SKU cannot take a switch. For a 450mm stroke, use external guides to prevent rod bending.
| Model | Airtac SIJ63 Double Rod Adjustable Cylinder SIJ63X450-75 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAIJ63X450-75 |
| Bore size | Ø63 mm |
| Stroke | 450 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 SAIJ63X450-75 carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 1559 N | 1402 N |
| 0.7 MPa | 2182 N | — |
| Max (@1.0 MPa) | 318 kgf | |
The SAIJ63X450-75 produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 63 | Bore size in mm. |
| ×450 | 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).
A machining fixture requiring field stroke tuning to accommodate multiple part heights without swapping the entire cylinder.
A material handling line needing on-site extend stroke adjustment to push varying box sizes onto different downstream lanes.
A packaging station that trims the extend stroke to apply seals at different carton depths while maintaining precise end positioning.
To replace the discontinued SIJ63X450-75, order the direct replacement SAIJ63X450-75. It keeps the 63mm bore, 450mm stroke, 75mm adjust window, G3/8 port, and FA/LB/TC mountings. Choose the 75mm adjust window if you need to trim the extend stroke on-site by up to 75mm. This SKU lacks the -S magnet and cannot take a sensor. Because the 450mm stroke exceeds 300mm, account for side-load and rod-bending by fitting external guides. The external stop screw sets end position but is not a lock; for load holding on air loss, use an external rod lock or pilot-operated check valve.
Replacement checklist
Yes, the SIJ63X450-75 is discontinued. The direct replacement is the SAIJ63X450-75, which shares the same ISO 15552 interface, 63mm bore, 450mm stroke, 75mm adjust window, G3/8 port, and mounting options.
The external stop screw window is 75mm, allowing you to trim the extend stroke from the 450mm maximum down to 375mm on-site. The stop sets end position and is not a load lock.
Send us the quantity and destination. We confirm price, stock and lead time on the SAIJ63X450-75 replacement — usually within 7-8 hours.