This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X120FA, 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 SI40X120FA
The AirTAC Airtac SI40 Standard Cylinder SI40X120FA 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 SAI40X120FA, 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 → SAI40X120FA
- 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 SI40X120FA
The AirTAC SI40X120FA is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 120mm stroke. Delivering 628N push force at 0.5MPa via a G1/4 port, it is replaced by the SAI40X120FA. This direct successor matches the bore, stroke, force, port and FA flange interface, dropping directly into existing fixtures. Note this specific SKU lacks a magnet (-S) and cannot accept a position sensor.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and long life. For load holding, note the air cushion only decelerates; use an external rod lock or SAIL/BSAI variant. The SAI family also adds SAIF self-valve options the SI lacked.
Airtac SI40 Standard Cylinder SI40X120FA Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X120FA |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X120FA |
| 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 SAI40X120FA 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 SAI40X120FA 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 SI40X120FA
| 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 SI40X120FA Is Used
Clamp Actuation
Provides 628N of clamping force at 0.5MPa for securing mid-sized workpieces during machining operations.
Package Diverting
Drives a 120mm stroke diverting arm on a packaging line to route standard cartons at speeds up to 800mm/s.
Gate Control
Operates access gates or lightweight material stops using the FA flange mount for secure fixture integration.
Replacing the Airtac SI40 Standard Cylinder SI40X120FA with the SAI40X120FA
To replace the SI40X120FA, order the SAI40X120FA, confirming the ISO 15552 interface, 40mm bore, 120mm stroke, G1/4 port (PT/G/NPT thread), and FA flange mounting. Because this SKU lacks a magnet, it cannot support legacy CS1-B/DS1-B sensors; order an SAI with the S suffix if sensing is needed. Sizing both ways: a neighbouring 50mm bore yields 982N push at 0.5MPa, while dropping to 32mm provides 402N. For load holding, a plain cylinder drifts on air loss—the cushion only decelerates—so specify an external pilot check valve or the SAIL lock variant. Rod material options include carbon steel, SUS420J2 (A) or SUS304 (B).
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X120FA
- ✓ 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 SI40X120FA FAQ
Yes, the AirTAC SI40X120FA is discontinued. The direct replacement is the SAI40X120FA. It is dimensionally interchangeable per ISO 15552, matching the 40mm bore, 120mm stroke, 628N force, G1/4 port, and FA flange mounting interface.
The 40mm bore features a G1/4 air port and M12x1.25 rod thread. Force output is 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 SAI40X120FA
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X120FA replacement — usually within 7-8 hours.