This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X175FA, 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 SI125X175FA
The AirTAC Airtac SI125 Standard Cylinder SI125X175FA is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 175mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X175FA, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke175 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X175FA
- 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 SI125X175FA
The AirTAC SI125X175FA is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 175 mm stroke. Delivering 6136 N push force at 0.5 MPa, it is replaced by the SAI125X175FA. This direct successor retains the exact FA flange mount, G1/2 port, and dimensions. The SAI features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life.
Because this SKU lacks the -S magnet option, it cannot accept a position sensor. The original SI used CS1-B/DS1-B switches, but this bare model cannot take one. The SAI family also introduces variants the SI lacked, such as the SAIL air-released lock, SAIF integrated valve, and BSAI clamp-lock. Note that a plain cylinder does not hold load without live air; the 40 mm adjustable cushion only decelerates near stroke end. For secure holding, use an external rod lock or pilot check valve.
Airtac SI125 Standard Cylinder SI125X175FA Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X175FA |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X175FA |
| Bore size | Ø125 mm |
| Stroke | 175 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 SAI125X175FA 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 SAI125X175FA 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 SI125X175FA
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×175 | 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 SI125X175FA Is Used
Heavy Press Clamping
Secures large metal castings in machining fixtures, utilizing the 6136 N push force at 0.5 MPa to hold components rigidly against cutting forces.
Automated Assembly Indexing
Shifts heavy automotive sub-assemblies between workstation stations using the FA flange mount to withstand high moment loads during transit.
Replacing the Airtac SI125 Standard Cylinder SI125X175FA with the SAI125X175FA
To replace the discontinued SI125X175FA, order the SAI125X175FA. Verify your ISO 15552 FA flange mounting interface, 125 mm bore, 175 mm stroke, and G1/2 port. This non-magnetic SKU cannot accept a sensor. If sizing both ways, neighbouring bores are 100 mm (3927 N push @0.5 MPa) and 160 mm (10053 N push @0.5 MPa). For load holding, remember the cushion only decelerates; use a SAIL lock or external pilot check valve to prevent drift on air loss.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X175FA
- ✓ 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 SI125X175FA FAQ
Yes, the SI125X175FA is discontinued. The direct replacement is the SAI125X175FA. It is dimensionally interchangeable per ISO 15552, retaining the same 125 mm bore, 175 mm stroke, FA flange mount, and G1/2 port.
This double-acting cylinder features a G1/2 port. 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.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X175FA
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X175FA replacement — usually within 7-8 hours.