This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X435, 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 SI125 Standard Cylinder SI125X435
The AirTAC SI125 Standard Cylinder SI125X435 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 435mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X435, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke435 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X435
- 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 SI125 Standard Cylinder SI125X435
The AirTAC SI125X435 is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 435 mm stroke, delivering 6136 N push force at 0.5 MPa through its G1/2 port. AirTAC replaced this legacy unit with the SAI125X435. This current-production direct maintains the exact ISO 15552 mounting interface, bore, stroke, force, port and mounting accessories, fitting existing fixtures perfectly.
The SAI upgrade features a redesigned piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. Note this specific SKU lacks a magnet (-S) and cannot accept position sensors. For elevated temperatures, Viton H seals extend operation to 150 C.
Airtac SI125 Standard Cylinder SI125X435 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X435 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X435 |
| Bore size | Ø125 mm |
| Stroke | 435 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 SAI125X435 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 SAI125X435 produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SI125 Standard Cylinder SI125X435
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×435 | 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 SI125 Standard Cylinder SI125X435 Is Used
Heavy Press Clamping
Secures large metal castings during machining operations, utilizing the 6136 N push force at 0.5 MPa to hold components rigidly against cutting forces.
Pallet Diversion
Drives heavy-duty diverters on automated packaging lines over the 435 mm stroke, moving loaded pallets laterally between adjacent belt sections.
Replacing the Airtac SI125 Standard Cylinder SI125X435 with the SAI125X435
To replace the SI125X435, order the SAI125X435 and confirm the ISO 15552 mounting interface, 435 mm stroke, G1/2 port (PT/G/NPT thread options), and your mounting accessory (LB, FA, TC, etc.). Because this SKU lacks the -S magnet, it cannot accept CS1-B/DS1-B sensors; if sensing is needed, specify an SAI125X435S. Sizing both ways: the 125 mm bore yields 6136 N push at 0.5 MPa, while the neighboring 100 mm bore offers 3927 N. If downsizing, verify your load. With a 435 mm stroke, use external guides to prevent rod bending and side-load damage. A plain cylinder drifts on air loss—the cushion only decelerates—so use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant for load holding.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X435
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SI125 Standard Cylinder SI125X435 FAQ
Yes, the SI125X435 is discontinued. The direct replacement is the AirTAC SAI125X435. It is dimensionally interchangeable per ISO 15552, matching the 125 mm bore, 435 mm stroke, G1/2 port, and output force, so it drops directly into existing fixtures.
This 125 mm bore cylinder features a G1/2 air port and M27x2 rod thread. It delivers 6136 N push and 5734 N pull at 0.5 MPa, 8590 N push at 0.7 MPa, 11045 N push at 0.9 MPa, and a theoretical maximum of 1251 kgf at 1.0 MPa. Operating speed is 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X435
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X435 replacement — usually within 7-8 hours.