This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X115S, 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 SI125X115S
The AirTAC SI125 Standard Cylinder SI125X115S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 115mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X115S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke115 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X115S
- 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 SI125X115S
The AirTAC SI125X115S is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 115 mm stroke, delivering 6136 N push force at 0.5 MPa. It features a Ø32 mm rod, M27x2 thread, and a G1/2 port. The direct replacement is the SAI125X115S, matching the bore, stroke, force, port, and ISO 15552 mounting interface exactly.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and long life. The SAI family also adds SAIL and BSAI lock variants the SI lacked. This -S model carries a piston magnet for CS1-B/DS1-B sensors; the SAI uses current AirTAC switches.
Airtac SI125 Standard Cylinder SI125X115S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X115S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X115S |
| Bore size | Ø125 mm |
| Stroke | 115 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 SAI125X115S 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 SAI125X115S 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 SI125X115S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×115 | 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 SI125X115S Is Used
Heavy Press Clamping
Secures large metalwork assemblies in machining fixtures, utilizing the 6136 N push force at 0.5 MPa to hold components rigidly against cutting loads.
Injection Mold Ejection
Drives large ejection plates in plastic molding lines, relying on the 115 mm stroke and adjustable 40 mm air cushions to decelerate heavy tooling safely.
Replacing the Airtac SI125 Standard Cylinder SI125X115S with the SAI125X115S
To replace the SI125X115S, order the SAI125X115S, confirming the ISO 15552 interface, 115 mm stroke, G1/2 port, and mounting accessory. The -S suffix means a magnet is required for CS1-B/DS1-B switches. If sizing down, the 100 mm bore offers 3927 N at 0.5 MPa; if sizing up, the 160 mm bore provides 10053 N. Remember 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 options include carbon steel, SUS420J2, or SUS304.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X115S
- ✓ 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 SI125X115S FAQ
Yes, the AirTAC SI125X115S is discontinued. The direct replacement is the SAI125X115S. It is dimensionally interchangeable per ISO 15552, retaining the same 125 mm bore, 115 mm stroke, 6136 N force, G1/2 port, and mounting interface.
The 125 mm bore uses a G1/2 port. At 0.5 MPa it provides 6136 N push and 5734 N pull. 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 SAI125X115S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X115S replacement — usually within 7-8 hours.