This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI100AX550S, 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 SI100 Standard Cylinder SI100AX550S
The AirTAC Airtac SI100 Standard Cylinder SI100AX550S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø100mm bore and 550mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI100AX550S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ100 mm
- Stroke550 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM20×1.5
- StatusDiscontinued → SAI100AX550S
- 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 SI100 Standard Cylinder SI100AX550S
The AirTAC SI100AX550S is a discontinued double-acting ISO 15552 profile cylinder with a 100mm bore, 550mm stroke, and SUS420J2 stainless steel rod. Delivering 3927 N push force at 0.5 MPa, it is replaced by the SAI100AX550S. This direct successor shares the exact ISO 15552 mounting interface, G1/2 port, and M20x1.5 rod thread, fitting existing fixtures perfectly.
The SAI upgrade features a new piston seal with two Y-shaped one-way elements for low start-up pressure and long life. The -S magnet works with legacy CS1-B/DS1-B sensors, while the SAI family adds SAIL and BSAI lock variants the SI lacked.
Airtac SI100 Standard Cylinder SI100AX550S Technical Specifications
| Model | Airtac SI100 Standard Cylinder SI100AX550S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI100AX550S |
| Bore size | Ø100 mm |
| Stroke | 550 mm |
| Acting type | Double acting |
| Port size | G1/2 |
| Rod thread | M20×1.5 |
| 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 – 800 mm/s |
| Cushion | Adjustable, 36 mm |
| Max standard stroke | Up to 1500 mm |
Specifications follow the official AirTAC SI datasheet (now discontinued). The SAI100AX550S carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
Theoretical Output Force (Ø100mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 3927 N | 3682 N |
| 0.7 MPa | 5498 N | — |
| Max (@1.0 MPa) | 801 kgf | |
The SAI100AX550S produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SI100 Standard Cylinder SI100AX550S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 100 | Bore size in mm. |
| ×550 | 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 SI100 Standard Cylinder SI100AX550S Is Used
Large Press Dampening
Ideal for heavy press operations requiring the full 3927 N push force at 0.5 MPa, utilizing the 36mm adjustable air cushions to absorb high kinetic energy at stroke ends.
Stainless Rod Washdown
The SUS420J2 stainless steel rod option provides necessary corrosion resistance for food or washdown environments where standard carbon steel rods would fail.
Replacing the Airtac SI100 Standard Cylinder SI100AX550S with the SAI100AX550S
To replace the SI100AX550S, order the SAI100AX550S. Verify the ISO 15552 mounting interface, the G1/2 air port (PT/G/NPT thread), and your mounting accessory (LB, FA, TC, etc.). The -S denotes a piston magnet for CS1-B/DS1-B switches; the SAI replacement uses current AirTAC switches. Sizing both ways: a neighbouring 80mm bore yields 2513 N push at 0.5 MPa, whereas a 125mm bore yields 6136 N. Note that a plain cylinder drifts on air loss—the cushion only decelerates—so for load holding use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant. Because the 550mm stroke exceeds 300mm, use external guides to prevent rod bending and side-load wear.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI100AX550S
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SI100 Standard Cylinder SI100AX550S FAQ
Yes, the SI100AX550S is discontinued. The direct replacement is the AirTAC SAI100AX550S. It shares the identical ISO 15552 mounting interface, 100mm bore, 550mm stroke, output force, and G1/2 port, so it drops directly into existing machinery without modifications.
This 100mm bore double-acting cylinder has a G1/2 air port and an M20x1.5 rod thread. The thrust ratings are: 3927 N push and 3681 N pull at 0.5 MPa; 5497 N push at 0.7 MPa; 7068 N push at 0.9 MPa; and a theoretical maximum of 801 kgf at 1.0 MPa. Operating speed is 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI100AX550S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI100AX550S replacement — usually within 7-8 hours.