This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X75S, 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 SI40X75S
The AirTAC Airtac SI40 Standard Cylinder SI40X75S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 75mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X75S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke75 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X75S
- 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 SI40X75S
The AirTAC SI40X75S is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 75mm stroke, delivering 628N push force at 0.5MPa through a G1/4 port. AirTAC replaced this legacy unit with the SAI40X75S. This current-production direct maintains the exact interface, bore, stroke, force and mounting, fitting existing fixtures perfectly.
The SAI upgrade features a refined piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. Beyond the standard carbon rod, options include SUS420J2 (A) or SUS304 (B) stems, plus Viton H seals for 0-150C duties. This magnet-equipped -S SKU supports CS1-B/DS1-B switches.
Airtac SI40 Standard Cylinder SI40X75S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X75S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X75S |
| Bore size | Ø40 mm |
| Stroke | 75 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 SAI40X75S 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 SAI40X75S 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 SI40X75S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×75 | 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 SI40X75S Is Used
Component Clamping
Ideal for securing mid-weight machined parts during milling or drilling, utilizing the 628N push force at 0.5MPa for rigid hold-down operations.
Package Diverting
Drives short 75mm stroke diverting arms on packaging lines to route boxes, relying on the 528N pull force to retract the mechanism quickly.
Replacing the Airtac SI40 Standard Cylinder SI40X75S with the SAI40X75S
To replace the SI40X75S, order the SAI40X75S and confirm the ISO 15552 mounting interface, 40mm bore, 75mm stroke, G1/4 port (PT/G/NPT thread) and your specific mounting accessory. The built-in magnet (-S) allows legacy CS1-B/DS1-B sensors to function, though the SAI family uses current AirTAC switches. If you need more force, the neighbouring 50mm bore offers 982N push @0.5MPa; if less is required, the 32mm bore provides 402N. Remember this plain cylinder does not hold load without live air; for drop prevention use an external pilot check valve or explore the SAIL (air-released lock) and BSAI (clamp-lock) variants. The SAIF variant with a built-in 4M valve is also available for this 40mm bore.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X75S
- ✓ 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 SI40X75S FAQ
Yes, the SI40X75S is discontinued. The direct replacement is the SAI40X75S. It is dimensionally interchangeable per ISO 15552, matching the 40mm bore, 75mm stroke, G1/4 port and mounting interface, so it drops directly into existing fixtures.
This double-acting cylinder uses a G1/4 air port. It generates 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.
Request a Quote for the SAI40X75S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X75S replacement — usually within 7-8 hours.