This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125AX85, 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 SI125AX85
The AirTAC Airtac SI125 Standard Cylinder SI125AX85 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 85mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125AX85, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke85 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125AX85
- 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 SI125AX85
The AirTAC SI125AX85 is a discontinued double-acting ISO 15552 profile cylinder with an extruded aluminum barrel, 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 SAI125AX85, matching the bore, stroke, port, and ISO 15552 mounting interface for immediate fixture compatibility.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and long life. This SI125AX85 variant uses an A-designated SUS420J2 stainless steel rod for corrosion resistance, but lacks a magnet so it cannot accept a sensor.
Airtac SI125 Standard Cylinder SI125AX85 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125AX85 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125AX85 |
| Bore size | Ø125 mm |
| Stroke | 85 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 SAI125AX85 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 SAI125AX85 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 SI125AX85
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×85 | 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 SI125AX85 Is Used
Heavy Stamping Press
Drives large platens and heavy stamping dies requiring 6136 N of thrust at 0.5 MPa with stable 125 mm bore guidance.
Injection Mold Clamp
Secures heavy injection molding tooling using the SUS420J2 stainless rod option to resist environmental corrosion.
Replacing the Airtac SI125 Standard Cylinder SI125AX85 with the SAI125AX85
To replace the SI125AX85, order the SAI125AX85. Verify your ISO 15552 mounting hardware (LB, FA, TC, etc.), the 125 mm bore, 85 mm stroke, and G1/2 port. Because this SKU lacks the -S magnet, it cannot support CS1-B/DS1-B switches; if sensing is needed, select an SAI model with the S suffix. For load holding, note that a standard cylinder drifts on air loss—the cushion only decelerates. Use an external pilot check valve or the SAIL/BSAI lock variants. If scaling up or down, neighboring bores are 100 mm (3927 N push @0.5 MPa) and 160 mm (10053 N push @0.5 MPa).
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125AX85
- ✓ 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 SI125AX85 FAQ
Yes, the AirTAC SI125AX85 is discontinued. The direct replacement is the SAI125AX85. It is dimensionally interchangeable per ISO 15552, retaining the same 125 mm bore, 85 mm stroke, 6136 N output force, G1/2 port, and mounting interface.
The G1/2 port bore delivers a push force of 6136 N and a pull force of 5734 N at 0.5 MPa. At 0.7 MPa the 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 SAI125AX85
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125AX85 replacement — usually within 7-8 hours.