This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X15SFA, 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 SI125X15SFA
The AirTAC SI125 Standard Cylinder SI125X15SFA is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 15mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X15SFA, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke15 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X15SFA
- 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 SI125X15SFA
The AirTAC SI125X15SFA is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore, 15 mm stroke, FA flange mounting, and a magnetic piston. Delivering 6136 N push force at 0.5 MPa, it features a 32 mm rod, M27x2 thread, and a G1/2 port. The direct replacement is the SAI125X15SFA, which matches the exact ISO 15552 mounting interface, bore, stroke, force, and port size.
The SAI125X15SFA upgrades the piston seal with two Y-shaped one-way elements for low start-up pressure and long life. The SAI family also introduces lock and clamp variants (SAIL, BSAI) absent in the legacy line. Your -S magnet works with legacy CS1-B/DS1-B sensors, while the SAI uses current AirTAC switches.
Airtac SI125 Standard Cylinder SI125X15SFA Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X15SFA |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X15SFA |
| Bore size | Ø125 mm |
| Stroke | 15 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 SAI125X15SFA 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 SAI125X15SFA 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 SI125X15SFA
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×15 | 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 SI125X15SFA Is Used
Heavy Press Operations
Applies 6136 N of thrust at 0.5 MPa for securely seating large bearings and heavy mechanical components in automated assembly lines.
High-Force Clamping Stations
Rigidly holds thick steel plates or cast parts during machining using the FA flange mount and 125 mm bore power.
Pallet Positioning Stops
Acts as a robust physical stop for heavy-loaded pallets, utilizing the 32 mm rod and short 15 mm stroke for impact resistance.
Replacing the Airtac SI125 Standard Cylinder SI125X15SFA with the SAI125X15SFA
To replace the discontinued SI125X15SFA, order the SAI125X15SFA. It is a direct per the ISO 15552 mounting interface, retaining the 125 mm bore, 15 mm stroke, G1/2 port, FA flange, and magnet. Confirm your thread option (PT, G, or NPT). For sizing both ways: a neighboring 100 mm bore yields 3927 N push at 0.5 MPa, while a 160 mm bore yields 10053 N. Note that a plain cylinder drifts on air loss—the cushion only decelerates. For load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants. Rod material options include carbon steel, SUS420J2 (A), or SUS304 (B).
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X15SFA
- ✓ 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 SI125X15SFA FAQ
Yes, the SI125X15SFA is discontinued. The direct replacement is the SAI125X15SFA. It matches the ISO 15552 mounting interface, 125 mm bore, 15 mm stroke, output force, G1/2 port, and FA flange, fitting existing fixtures perfectly.
It features a G1/2 port. The force ratings are: 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 max of 1251 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X15SFA
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X15SFA replacement — usually within 7-8 hours.