This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X510S, 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 SI125X510S
The AirTAC SI125 Standard Cylinder SI125X510S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 510mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X510S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke510 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X510S
- 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 SI125X510S
The AirTAC SI125X510S is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 510 mm stroke. It delivers 6136 N push force at 0.5 MPa through a G1/2 port. AirTAC replaced this legacy unit with the SAI125X510S, a direct upgrade retaining the exact ISO 15552 mounting interface, stroke, and output force.
The SAI upgrade features a refined piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. The -S suffix means this SKU includes a piston magnet for legacy CS1-B/DS1-B sensors, whereas the SAI family also adds SAIL lock and BSAI clamp-lock variants absent in the SI line.
Airtac SI125 Standard Cylinder SI125X510S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X510S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X510S |
| Bore size | Ø125 mm |
| Stroke | 510 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 SAI125X510S 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 SAI125X510S 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 SI125X510S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×510 | 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 SI125X510S Is Used
Heavy Press Staging
Ideal for positioning heavy metal blanks at 0.5 MPa, utilizing the 6136 N push force to feed materials into a hydraulic press.
Bulk Package Diversion
Actuates large industrial diverters on high-throughput packaging lines, relying on the adjustable 40 mm cushions to decelerate heavy masses.
Replacing the Airtac SI125 Standard Cylinder SI125X510S with the SAI125X510S
To replace the SI125X510S, order the SAI125X510S. Verify your ISO 15552 mounting accessory (LB, FA, TC, etc.), the G1/2 port, and the M27x2 rod thread. Because this is a 510 mm stroke, use external guides to prevent rod bending and side-load damage. If sizing up or down, note the 100 mm bore offers 3927 N push at 0.5 MPa, while the 160 mm bore provides 10053 N. A plain cylinder drifts on air loss—the cushion only decelerates—so for load holding specify the SAIL lock, BSAI clamp-lock, or an external pilot check valve.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X510S
- ✓ 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 SI125X510S FAQ
Yes, the SI125X510S is discontinued. The direct replacement is the AirTAC SAI125X510S. It is dimensionally interchangeable per ISO 15552, matching the 125 mm bore, 510 mm stroke, G1/2 port, and output force, so it drops directly into existing fixtures.
At 0.5 MPa it pushes 6136 N and pulls 5734 N. At 0.7 MPa push is 8590 N, and at 0.9 MPa it is 11045 N. The theoretical max force is 1251 kgf at 1.0 MPa. It operates at 30-500 mm/s, uses a G1/2 port, and the -S suffix indicates a magnet for CS1-B/DS1-B switches.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X510S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X510S replacement — usually within 7-8 hours.