This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAIJ125X450-50S, 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 SIJ125 Double Rod Adjustable Cylinder SIJ125X450-50S
The AirTAC SIJ125 Double Rod Adjustable Cylinder SIJ125X450-50S 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 SAIJ125X450-50S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke450 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAIJ125X450-50S
- 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 SIJ125 Double Rod Adjustable Cylinder SIJ125X450-50S
The AirTAC SIJ125X450-50S is a discontinued double-acting double-rod ISO 15552 adjustable-stroke cylinder. An external stop screw lets you trim the extend stroke by up to 50mm on-site, yielding a usable 400-450mm stroke from the 450mm nominal maximum. The direct replacement is the SAIJ125X450-50S, matching the interface, force, and mounting.
The stop screw sets the end position but is not a load lock; use an external rod lock or SAIL/BSAI variant for held loads. The SAIJ upgrade features a two Y-shaped one-way piston seal for low start-up pressure. The -S suffix provides a piston magnet for legacy CS1-B/DS1-B switches.
Airtac SIJ125 Double Rod Adjustable Cylinder SIJ125X450-50S Technical Specifications
| Model | Airtac SIJ125 Double Rod Adjustable Cylinder SIJ125X450-50S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAIJ125X450-50S |
| 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 SAIJ125X450-50S carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
Theoretical Output Force (Ø125mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 6136 N | 5734 N |
| 0.7 MPa | 8590 N | — |
| Max (@1.0 MPa) | 1251 kgf | |
The SAIJ125X450-50S produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SIJ125 Double Rod Adjustable Cylinder SIJ125X450-50S
| 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).
Where the Airtac SIJ125 Double Rod Adjustable Cylinder SIJ125X450-50S Is Used
Press Fit Tuning
Allows on-site extend stroke trimming up to 50mm to set precise bottoming depth for pressing bearings without machining hard stops.
Variable Height Sealing
Adjusts the extend endpoint on packaging lines to seal cartons of varying heights, using the external screw to dial in the exact 400-450mm position.
Adjustable Stops
Sets intermediate end positions for diverter gates or pallet stops, trimming the stroke by up to 50mm to accommodate different pallet sizes.
Replacing the Airtac SIJ125 Double Rod Adjustable Cylinder SIJ125X450-50S with the SAIJ125X450-50S
To replace the discontinued SIJ125X450-50S, order the direct replacement SAIJ125X450-50S, retaining the 450mm stroke, 50mm adjust window, and -S magnet. Choose the 50mm adjust window if you need precise on-site end-position tuning between 400-450mm; the stop screw sets position but does not lock the load. Mounting options include FA, LB, and TC. For this 450mm stroke, support the rod against bending and use external guides to manage side loads.
Replacement checklist
- ✓ Same ISO 15552 interface → SAIJ125X450-50S
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SIJ125 Double Rod Adjustable Cylinder SIJ125X450-50S FAQ
Yes, the SIJ125X450-50S is discontinued. The direct replacement is the SAIJ125X450-50S, which shares the same ISO 15552 interface, 125mm bore, 450mm stroke, 50mm adjust window, G1/2 port, and mounting options. The SAIJ also uses an upgraded two Y-shaped one-way piston seal for longer life.
The external stop screw provides a 50mm adjust window, shortening the extend stroke from 450mm down to 400mm. The stop sets end position but is not a load lock.
Related AirTAC SAI Cylinders
Request a Quote for the SAIJ125X450-50S
Send us the quantity and destination. We confirm price, stock and lead time on the SAIJ125X450-50S replacement — usually within 7-8 hours.