This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X205S, 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 SI40 Standard Cylinder SI40X205S
The AirTAC Airtac SI40 Standard Cylinder SI40X205S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 205mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X205S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke205 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X205S
- 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 SI40 Standard Cylinder SI40X205S
The AirTAC SI40X205S is a discontinued double-acting ISO 15552 profile cylinder with a 40 mm bore and 205 mm stroke, delivering 628 N push force at 0.5 MPa. AirTAC replaced it with the SAI40X205S, a direct upgrade retaining the exact G1/4 port, M12x1.25 rod thread, and ISO 15552 mounting interface.
The SAI upgrade features a new piston seal with two Y-shaped one-way elements for low start-up pressure and long life. This -S model includes a piston magnet for CS1-B/DS1-B sensors, and seal options include high-temp Viton H.
Airtac SI40 Standard Cylinder SI40X205S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X205S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X205S |
| Bore size | Ø40 mm |
| Stroke | 205 mm |
| Acting type | Double acting |
| Port size | G1/4 |
| Rod thread | M12×1.25 |
| 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, 27 mm |
| Max standard stroke | Up to 1200 mm |
Specifications follow the official AirTAC SI datasheet (now discontinued). The SAI40X205S carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
Theoretical Output Force (Ø40mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 628 N | 528 N |
| 0.7 MPa | 880 N | — |
| Max (@1.0 MPa) | 128 kgf | |
The SAI40X205S produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SI40 Standard Cylinder SI40X205S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×205 | 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 SI40 Standard Cylinder SI40X205S Is Used
Component Clamping
Secures mid-weight machined parts during milling or drilling, using the 628 N push force to hold firmly against cutting vibration.
Package Diversion
Actuates routing gates on packaging lines, providing reliable 205 mm travel to redirect cartons at speeds up to 800 mm/s.
Vertical Lift Stops
Raises lightweight product stops or elevates ~32 kg loads vertically in distribution hubs when paired with proper guide rails.
Replacing the Airtac SI40 Standard Cylinder SI40X205S with the SAI40X205S
To replace this SI40X205S, order the SAI40X205S keeping the same 40 mm bore, 205 mm stroke, G1/4 port, and -S magnet. Confirm your ISO 15552 mounting accessory (LB, FA, TC, etc.) and thread type (PT, G, NPT). For sizing both ways: a neighbouring 32 mm bore yields 402 N push at 0.5 MPa, while a 50 mm bore yields 982 N. Note that a plain cylinder does not hold load on air loss; the 27 mm adjustable cushion only decelerates. For load holding, use the SAIL lock or BSAI clamp-lock variant, or an external pilot check valve. For this 205 mm stroke, ensure guide support to prevent rod bending and side loads.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X205S
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SI40 Standard Cylinder SI40X205S FAQ
Yes, the SI40X205S is discontinued. The direct replacement is the AirTAC SAI40X205S. It is dimensionally interchangeable per ISO 15552, matching the 40 mm bore, 205 mm stroke, G1/4 port, and mounting interface, so it fits existing fixtures perfectly.
The G1/4 port is fixed by the 40 mm bore. At 0.5 MPa it provides 628 N push and 528 N pull force. At 0.7 MPa push is 879 N, at 0.9 MPa it is 1130 N, and the theoretical maximum is 128 kgf at 1.0 MPa. Operating speed is 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X205S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X205S replacement — usually within 7-8 hours.