This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X120, 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 SI50 Standard Cylinder SI50X120
The AirTAC Airtac SI50 Standard Cylinder SI50X120 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 120mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X120, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke120 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X120
- 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 SI50 Standard Cylinder SI50X120
The AirTAC SI50X120 is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 120mm stroke. Delivering 982N push force at 0.5MPa, it is directly replaced by the SAI50X120. This direct upgrade shares the exact same G1/4 port, M16x1.5 rod thread, and ISO 15552 mounting interface, fitting existing fixtures perfectly.
The SAI replacement features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. Note this non-magnet SKU cannot take a sensor; legacy CS1-B/DS1-B switches require an -S variant. The SAI family also adds SAIL lock, SAIF valve, and BSAI clamp-lock options.
Airtac SI50 Standard Cylinder SI50X120 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X120 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X120 |
| Bore size | Ø50 mm |
| Stroke | 120 mm |
| Acting type | Double acting |
| Port size | G1/4 |
| Rod thread | M16×1.5 |
| 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, 30 mm |
| Max standard stroke | Up to 1200 mm |
Specifications follow the official AirTAC SI datasheet (now discontinued). The SAI50X120 carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
Theoretical Output Force (Ø50mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 982 N | 825 N |
| 0.7 MPa | 1374 N | — |
| Max (@1.0 MPa) | 200 kgf | |
The SAI50X120 produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SI50 Standard Cylinder SI50X120
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | 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 SI50 Standard Cylinder SI50X120 Is Used
Package Diversion
Actuates routing gates on packaging lines, using the 982N thrust at 0.5MPa to push standard cartons reliably at cycle speeds within the 30-800mm/s range.
Clamp Actuation
Provides repeatable clamping force for mid-weight aluminium fixtures during machining, utilizing the 120mm stroke to clear the workpiece for loading.
Replacing the Airtac SI50 Standard Cylinder SI50X120 with the SAI50X120
To replace the discontinued SI50X120, order the SAI50X120. Confirm your ISO 15552 mounting accessory (LB, FA, TC, etc.), the 120mm stroke, and the G1/4 port (PT/G/NPT). Because this specific SKU lacks the -S magnet, it cannot accept position sensors; if sensing is needed, select the SAI50X120S instead. Size both ways: the neighbouring 63mm bore yields 1559N push at 0.5MPa, while the 40mm bore yields 628N. Remember, a plain cylinder does not hold load on air loss—the cushion only decelerates. For load holding, use an external pilot check valve or explore the SAIL or BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X120
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SI50 Standard Cylinder SI50X120 FAQ
Yes, the SI50X120 is discontinued. The direct replacement is the AirTAC SAI50X120. It is dimensionally interchangeable per ISO 15552, retaining the same 50mm bore, 120mm stroke, G1/4 port, and mounting interface.
It features a G1/4 air port and M16x1.5 rod thread. Force output is 982N push and 825N pull at 0.5MPa, 1374N push at 0.7MPa, 1767N push at 0.9MPa, with a theoretical maximum of 200kgf at 1.0MPa.
Request a Quote for the SAI50X120
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X120 replacement — usually within 7-8 hours.