This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAIJ125X450-30, 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 SIJ125 Double Rod Adjustable Cylinder SIJ125X450-30 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 450mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAIJ125X450-30, which matches its ISO interface, bore, stroke, force and mounting.
The AirTAC SIJ125X450-30 is a discontinued double-acting double-rod ISO 15552 adjustable-stroke cylinder with a 125 mm bore and 450 mm maximum stroke. An external stop screw lets you trim the extend stroke by up to 30 mm on-site, yielding a usable 420-450 mm extension window. The direct replacement is the SAIJ125X450-30, matching the interface, force, and mounting.
The SAIJ successor retains the ISO 15552 mounting dimensions for direct reuse of FA, LB, and TC brackets, and upgrades the piston seal to two Y-shaped one-way elements for lower start-up pressure and longer life. As this SKU lacks a -S magnet, it cannot accept a magnetic switch. Note the stop screw sets end position only; it is not a load lock.
| Model | Airtac SIJ125 Double Rod Adjustable Cylinder SIJ125X450-30 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAIJ125X450-30 |
| Bore size | Ø125 mm |
| Stroke | 450 mm |
| Acting type | Double acting |
| Port size | G1/2 |
| Rod thread | M27×2.0 |
| 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 – 500 mm/s |
| Cushion | Adjustable, 40 mm |
| Max standard stroke | Up to 1500 mm |
Specifications follow the official AirTAC SI datasheet (now discontinued). The SAIJ125X450-30 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 | 6136 N | 5734 N |
| 0.7 MPa | 8590 N | — |
| Max (@1.0 MPa) | 1251 kgf | |
The SAIJ125X450-30 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). |
|---|---|
| 125 | 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).
Bearing press operations needing field stroke tuning to dial in the exact 420-450 mm extend position without re-engineering the fixture.
Pallet divertor arms requiring on-site stroke trimming to accommodate varying product widths on the fly.
Heavy-duty stacking units where the extend stop is adjusted to set precise layer drop heights for different pallet loads.
To replace the discontinued SIJ125X450-30, order the exact direct replacement SAIJ125X450-30, keeping the 30 mm adjust window (420-450 mm usable extend) and G1/2 port. Mounting interfaces (Basic, FA, LB, TC) are genuine ISO 15552 dimensions, allowing bracket reuse. Because the 450 mm stroke is long, verify side-load limits and use external guides to prevent rod bending. The external stop sets end position but is not a lock; for load holding on air loss, use an external rod lock or the SAIL/BSAI variants.
Replacement checklist
Yes, the SIJ125X450-30 is discontinued. The direct replacement is the SAIJ125X450-30. It shares the identical ISO 15552 interface, 125 mm bore, 450 mm stroke, 30 mm adjust window, G1/2 port, and mounting options, but features an upgraded two Y-shaped one-way piston seal.
The external stop screw window is 30 mm, allowing you to trim the 450 mm nominal extend stroke down to 420 mm on-site. The stop sets end position only and is not a load lock.
Send us the quantity and destination. We confirm price, stock and lead time on the SAIJ125X450-30 replacement — usually within 7-8 hours.