This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X120SN, 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 SI40X120SN
The AirTAC SI40 Standard Cylinder SI40X120SN is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 120mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X120SN, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke120 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X120SN
- 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 SI40X120SN
The AirTAC SI40X120SN is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 120mm stroke. It delivers 628N push force at 0.5MPa via a G1/4 port. The direct replacement is the SAI40X120SN, matching the bore, stroke, force, port, and ISO 15552 mounting interface for existing fixtures.
The SAI upgrade features two Y-shaped one-way piston seals for low start-up pressure. The NBR seal handles -20 to +70C, while a Viton H option extends this to 150C. The SAI family also adds SAIL, SAIF, and BSAI lock variants the SI lacked.
Airtac SI40 Standard Cylinder SI40X120SN Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X120SN |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X120SN |
| Bore size | Ø40 mm |
| Stroke | 120 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 SAI40X120SN 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 SAI40X120SN 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 SI40X120SN
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×120 | 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 SI40X120SN Is Used
Package Diverting
Actuates diverter arms on packaging lines using the 628N push force at 0.5MPa to redirect cartons efficiently.
Clamp Actuation
Provides reliable clamping pressure for lightweight machining fixtures, utilizing the 120mm stroke to accommodate part variance.
Replacing the Airtac SI40 Standard Cylinder SI40X120SN with the SAI40X120SN
To replace the SI40X120SN, order the SAI40X120SN direct. Confirm the ISO 15552 mounting interface, 120mm stroke, G1/4 port, and mounting accessory. The -S magnet works with legacy CS1-B/DS1-B switches, while the SAI uses current AirTAC switches. The -N NBR seal is standard. Sizing both ways: a 32mm bore yields 402N push at 0.5MPa, while a 50mm bore yields 982N. If load holding is required on air loss, note this plain cylinder drifts; use an external pilot check valve or the SAIL/BSAI lock variant. For 120mm strokes, ensure guide alignment to prevent rod bending.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X120SN
- ✓ 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 SI40X120SN FAQ
Yes, the SI40X120SN is discontinued. The direct replacement is the SAI40X120SN. It is dimensionally interchangeable per ISO 15552, retaining the same 40mm bore, 120mm stroke, force, and G1/4 port.
The G1/4 port bore delivers a push force of 628N and pull of 528N at 0.5MPa. At 0.7MPa push is 879N, at 0.9MPa it is 1130N, and the theoretical max is 128kgf at 1.0MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X120SN
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X120SN replacement — usually within 7-8 hours.