This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X1220STC, 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 SI40X1220STC
The AirTAC SI40 Standard Cylinder SI40X1220STC is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 1220mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X1220STC, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke1220 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X1220STC
- 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 SI40X1220STC
The AirTAC SI40X1220STC is a discontinued double-acting ISO 15552 profile cylinder featuring a 40mm bore, a 1220mm stroke, and a TC trunnion mount. Generating 628N push force at 0.5MPa, it utilized a G1/4 port and M12x1.25 rod thread. Because the 1220mm length exceeds the 1200mm standard maximum for this bore, it is a non-standard, made-to-order unit. The direct replacement is the SAI40X1220STC, which matches the original ISO 15552 mounting interface, bore, stroke, output force, and port size exactly.
The SAI upgrade introduces an advanced piston seal with two Y-shaped one-way elements, ensuring long life and low start-up pressure. The SAI family also adds variants the SI lacked, such as the SAIL air-released lock, SAIF built-in valve, and BSAI clamp-lock. This magnet-ready unit (-S) accepts legacy CS1-B/DS1-B sensors, while the SAI uses current AirTAC switches.
Airtac SI40 Standard Cylinder SI40X1220STC Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X1220STC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X1220STC |
| Bore size | Ø40 mm |
| Stroke | 1220 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 SAI40X1220STC 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 SAI40X1220STC 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 SI40X1220STC
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×1220 | 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 SI40X1220STC Is Used
Long-Stroke Material Transfer
Pushes products between conveyor lanes over a 1220mm distance using the 628N push force, requiring external guides to prevent rod bending on the extended stroke.
Replacing the Airtac SI40 Standard Cylinder SI40X1220STC with the SAI40X1220STC
To replace the discontinued SI40X1220STC, order the SAI40X1220STC. Verify the ISO 15552 TC trunnion mounting interface, the G1/4 port, the 1220mm stroke, and the -S magnet option. Because 1220mm exceeds the 1200mm standard maximum, expect a made-to-order lead time. When sizing, a 50mm bore offers 982N push at 0.5MPa if more force is needed, while a 32mm bore provides 402N for lighter loads. For this 1220mm stroke, external guides are strongly recommended to prevent rod bending and side-load damage. A plain cylinder drifts on air loss; the air cushion only decelerates near stroke end. For load holding, use an external rod lock, a pilot check valve, or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X1220STC
- ✓ 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 SI40X1220STC FAQ
Yes, the SI40X1220STC is discontinued. The direct replacement is the SAI40X1220STC. It is dimensionally interchangeable per ISO 15552, matching the 40mm bore, 1220mm stroke, TC mount, G1/4 port, and output force, fitting existing fixtures perfectly.
This double-acting cylinder features a G1/4 port and provides 628N push / 528N pull at 0.5MPa, 879N push at 0.7MPa, 1130N push at 0.9MPa, and a theoretical max of 128kgf at 1.0MPa. The 1220mm stroke is non-standard and requires external guides to manage side loads.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X1220STC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X1220STC replacement — usually within 7-8 hours.