This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125AX15, 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 SI125AX15
The AirTAC SI125 Standard Cylinder SI125AX15 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 SAI125AX15, 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 → SAI125AX15
- 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 SI125AX15
The AirTAC SI125AX15 is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 15 mm stroke. It delivers 6136 N push force at 0.5 MPa through a G1/2 port. The direct replacement is the SAI125AX15, matching the interface, bore, stroke, force, port and mounting.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. This SKU has an SUS420J2 stainless rod (A) but lacks a magnet, so it cannot take a CS1-B/DS1-B sensor. For high heat, Viton H seals raise the limit to 150 C.
Airtac SI125 Standard Cylinder SI125AX15 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125AX15 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125AX15 |
| 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 SAI125AX15 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 SAI125AX15 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 SI125AX15
| 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 SI125AX15 Is Used
Short-Stroke Clamping
Ideal for high-force short-stroke clamping of heavy steel plates in fabrication fixtures, utilizing the full 6136 N push force at 0.5 MPa.
Heavy Duty Ejection
Provides robust 15 mm ejection strokes in stamping presses, where the SUS420J2 stainless rod resists coolant and washdown fluids.
Rigid Stopper Blocks
Functions as a high-capacity pneumatic stopper in heavy material handling lines, safely halting pallets without needing full stroke extension.
Replacing the Airtac SI125 Standard Cylinder SI125AX15 with the SAI125AX15
To replace the SI125AX15, order the SAI125AX15. Verify the ISO 15552 mounting interface, 125 mm bore, 15 mm stroke, G1/2 port (PT/G/NPT thread) and mounting accessory. Because this SKU lacks a magnet (-S), it cannot accept a magnetic switch; order a magnet-equipped model if sensing is required. The SUS420J2 stainless rod option suits corrosive environments. Note that a plain cylinder drifts on air loss—the cushion only decelerates. For held loads, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125AX15
- ✓ 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 SI125AX15 FAQ
Yes, the AirTAC SI125AX15 is discontinued. The direct replacement is the SAI125AX15. It is dimensionally interchangeable per ISO 15552, retaining the same 125 mm bore, 15 mm stroke, 6136 N force, G1/2 port and mounting interface, so it fits existing fixtures perfectly.
This double-acting cylinder has a G1/2 port, a 32 mm rod, and an M27x2 rod thread. 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 maximum of 1251 kgf at 1.0 MPa. Operating speed is 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125AX15
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125AX15 replacement — usually within 7-8 hours.