This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X280S, 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 SI40X280S
The AirTAC Airtac SI40 Standard Cylinder SI40X280S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 280mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X280S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke280 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X280S
- 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 SI40X280S
The AirTAC SI40X280S is a discontinued double-acting ISO 15552 profile cylinder featuring a 40mm bore and 280mm stroke. It delivers 628N push force at 0.5MPa via a G1/4 port. AirTAC replaced this legacy unit with the SAI40X280S, a direct upgrade retaining the exact interface, bore, stroke, force, port and mounting fixtures.
The SAI replacement upgrades longevity with two Y-shaped one-way piston seals for low start-up pressure. For position sensing, this -S model has a piston magnet for legacy CS1-B/DS1-B switches, while the SAI uses current AirTAC sensors. For load holding, note that standard cylinders drift without live air; consider the SAIL lock or BSAI clamp-lock variants.
Airtac SI40 Standard Cylinder SI40X280S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X280S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X280S |
| Bore size | Ø40 mm |
| Stroke | 280 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 SAI40X280S 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 SAI40X280S 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 SI40X280S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×280 | 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 SI40X280S Is Used
Component Clamping
Secures mid-weight machined parts during milling or drilling, utilizing the 628N push force to hold firm against cutting vibration.
Package Diverting
Actuates routing gates on packaging lines, where the 280mm stroke provides ample travel to redirect boxes between parallel belts.
Replacing the Airtac SI40 Standard Cylinder SI40X280S with the SAI40X280S
To replace the SI40X280S, order the SAI40X280S, confirming the ISO 15552 interface, 40mm bore, 280mm stroke, G1/4 port (PT/G/NPT), and the -S magnet. If you need more force, the 50mm bore yields 982N push at 0.5MPa; if less is required, the 32mm bore provides 402N. At 280mm stroke, use guide rails to prevent rod bending and side-load wear. A plain cylinder does not hold load without air; for drop prevention, use an external pilot check valve or explore the SAIL or BSAI lock variants. The SAIF variant offers a built-in 4M valve for bores 32-100.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X280S
- ✓ 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 SI40X280S FAQ
Yes, the SI40X280S is discontinued. The direct replacement is the SAI40X280S. It is dimensionally interchangeable per ISO 15552, matching the 40mm bore, 280mm stroke, 628N force, G1/4 port and mounting interface, so it fits existing fixtures perfectly.
This 40mm bore double-acting cylinder features a G1/4 air port and M12x1.25 rod thread. It delivers 628N push and 528N pull at 0.5MPa, 879N push at 0.7MPa, 1130N push at 0.9MPa, and a theoretical maximum of 128kgf at 1.0MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X280S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X280S replacement — usually within 7-8 hours.