This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X350, 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 SI125X350
The AirTAC SI125 Standard Cylinder SI125X350 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 350mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X350, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke350 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X350
- 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 SI125X350
The AirTAC SI125X350 is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 350 mm stroke. It delivers 6136 N push force at 0.5 MPa and uses a G1/2 port. The direct replacement is the SAI125X350, matching the interface, bore, stroke, force, and mounting.
The SAI upgrade features two Y-shaped one-way piston seals for low start-up pressure and long life. Note this non-magnet SKU cannot take a sensor.
Airtac SI125 Standard Cylinder SI125X350 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X350 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X350 |
| Bore size | Ø125 mm |
| Stroke | 350 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 SAI125X350 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 SAI125X350 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 SI125X350
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×350 | 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 SI125X350 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 Dispenser
Actuates the lifting mechanism for heavy wooden pallets in automated storage lines, where the 350 mm stroke provides the necessary vertical travel distance.
Bulk Material Diversion
Drives large-scale deflector gates on conveyor systems to route heavy aggregate or packaged goods into secondary processing chutes.
Replacing the Airtac SI125 Standard Cylinder SI125X350 with the SAI125X350
To replace the SI125X350, order the SAI125X350 keeping the identical 125 mm bore, 350 mm stroke, G1/2 port, and ISO 15552 mounting. Confirm your thread option (PT, G, or NPT) and mounting accessory. Since this SKU lacks the -S magnet, it cannot accept CS1-B/DS1-B sensors; switch to a magnet-equipped SAI if position sensing is required. For sizing, the neighboring 100 mm bore yields 3927 N push at 0.5 MPa, while the 160 mm bore yields 10053 N. At 350 mm stroke, use external guides to prevent rod bending and side-load wear. The air cushion only decelerates the load; for dead-load holding, use an external rod lock, a pilot check valve, or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X350
- ✓ 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 SI125X350 FAQ
Yes, the SI125X350 is discontinued. The direct replacement is the AirTAC SAI125X350. It is dimensionally interchangeable per ISO 15552, offering the same 125 mm bore, 350 mm stroke, output force, G1/2 port, and mounting interface.
The bore is 125 mm with a G1/2 port. At 0.5 MPa it provides 6136 N push and 5734 N pull force. At 0.7 MPa push is 8590 N, and at 0.9 MPa it is 11045 N. The theoretical maximum force is 1251 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X350
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X350 replacement — usually within 7-8 hours.