This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X500FTC, 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 SI125X500FTC
The AirTAC SI125 Standard Cylinder SI125X500FTC is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 500mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X500FTC, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke500 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X500FTC
- 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 SI125X500FTC
The AirTAC SI125X500FTC is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 500 mm stroke. It delivers 6136 N push force at 0.5 MPa via a G1/2 port. The direct replacement is the SAI125X500FTC, matching the bore, stroke, force, port, and FTC trunnion mount exactly.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and long life. This SKU lacks a magnet, so it cannot take a CS1-B/DS1-B sensor. The SAI family also adds SAIL and BSAI lock variants the SI lacked.
Airtac SI125 Standard Cylinder SI125X500FTC Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X500FTC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X500FTC |
| Bore size | Ø125 mm |
| Stroke | 500 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 SAI125X500FTC 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 SAI125X500FTC 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 SI125X500FTC
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×500 | 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 SI125X500FTC Is Used
Heavy Press Ejection
Provides the robust 6136 N push force needed to eject dense stamped parts from heavy press dies.
Pallet Dispenser
Actuates large 500 mm strokes to feed empty pallets into automated packaging and warehousing lines.
Large Mold Handling
Shifts substantial injection molds along the FTC trunnion mount, absorbing high dynamic loads safely.
Replacing the Airtac SI125 Standard Cylinder SI125X500FTC with the SAI125X500FTC
To replace the SI125X500FTC, order the SAI125X500FTC. Verify the ISO 15552 FTC trunnion interface, 125 mm bore, 500 mm stroke, and G1/2 port (PT/G/NPT thread options). Because this SKU has no -S magnet, it cannot accept position sensors; order a magnet-equipped SAI if sensing is needed. At 0.5 MPa it pushes 6136 N (pulls 5734 N); neighbouring bores are 100 mm (3927 N) and 160 mm (10053 N). For the 500 mm stroke, use external guides to prevent rod bending and side-load wear. The air cushion only decelerates; it does not hold load on air loss. For load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X500FTC
- ✓ 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 SI125X500FTC FAQ
Yes, the SI125X500FTC is discontinued. The direct replacement is the SAI125X500FTC. It is dimensionally interchangeable per ISO 15552, retaining the same 125 mm bore, 500 mm stroke, G1/2 port, and FTC mounting interface.
The bore is 125 mm with a G1/2 air port and M27x2 rod thread. At 0.5 MPa it pushes 6136 N and pulls 5734 N. At 0.7 MPa it pushes 8590 N, and 11045 N at 0.9 MPa. The theoretical max force is 1251 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X500FTC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X500FTC replacement — usually within 7-8 hours.