This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X205SN, 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 SI125X205SN
The AirTAC SI125 Standard Cylinder SI125X205SN is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 205mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X205SN, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke205 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X205SN
- 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 SI125X205SN
The AirTAC SI125X205SN is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 205 mm stroke. It delivers 6136 N push force at 0.5 MPa via a G1/2 port. The direct replacement is the SAI125X205SN, matching the interface, bore, stroke, force, and mounting.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. The SI line lacked SAIL lock, SAIF valve, and BSAI clamp variants now available. The NBR seal handles -20 to +70 C, while Viton H extends this to 150 C.
Airtac SI125 Standard Cylinder SI125X205SN Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X205SN |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X205SN |
| Bore size | Ø125 mm |
| Stroke | 205 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 SAI125X205SN 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 SAI125X205SN 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 SI125X205SN
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×205 | 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 SI125X205SN Is Used
Heavy Press Clamping
Generates 6136 N at 0.5 MPa to secure large metal castings during machining operations.
Industrial Door Actuation
Drives robust 205 mm stroke cycles for automated heavy-duty facility access panels.
Replacing the Airtac SI125 Standard Cylinder SI125X205SN with the SAI125X205SN
To replace the SI125X205SN, order the SAI125X205SN direct, verifying the ISO 15552 mounting interface, 205 mm stroke, G1/2 port, and -S magnet for CS1-B/DS1-B legacy sensors. The SAI uses current AirTAC switches. If downsizing, a 100 mm bore yields 3927 N at 0.5 MPa; if upsizing, a 160 mm bore provides 10053 N. Because stroke is 205 mm, ensure guide alignment to prevent rod bending. A plain cylinder drifts on air loss; for load holding, use an external pilot check valve or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X205SN
- ✓ 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 SI125X205SN FAQ
Yes, the SI125X205SN is discontinued. The direct replacement is the SAI125X205SN. It is dimensionally interchangeable per ISO 15552, retaining the same 125 mm bore, 205 mm stroke, output force, G1/2 port, and mounting fixtures.
This double-acting cylinder uses 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 force of 1251 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X205SN
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X205SN replacement — usually within 7-8 hours.