This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X300S, 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 SI50X300S
The AirTAC SI50 Standard Cylinder SI50X300S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 300mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X300S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke300 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X300S
- 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 SI50X300S
The AirTAC SI50X300S is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 300mm stroke. It delivers 982N push force at 0.5MPa via a G1/4 port. The direct replacement is the SAI50X300S, matching the interface, bore, stroke, force, port and mounting.
The SAI upgrade features two Y-shaped one-way piston seals for low start-up pressure and long life. The SAI family also adds SAIL lock, SAIF valve and BSAI clamp-lock variants. This -S SKU uses CS1-B/DS1-B sensors.
Airtac SI50 Standard Cylinder SI50X300S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X300S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X300S |
| Bore size | Ø50 mm |
| Stroke | 300 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 SAI50X300S 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 SAI50X300S 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 SI50X300S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×300 | 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 SI50X300S Is Used
Package Diverting
Pushes cartons at 90 degrees on a sorting line using the 982N push force at 0.5MPa, with the 300mm stroke clearing adjacent lanes.
Pallet Stopper Gate
Acts as an indexing stop for pallets, where the 50kg vertical lift capacity and ISO 15552 mounting handle repetitive cycling reliably.
Vertical Pressing
Performs light-duty downward pressing or holding tasks, requiring external guides to manage side loads over the 300mm extension.
Replacing the Airtac SI50 Standard Cylinder SI50X300S with the SAI50X300S
To replace the SI50X300S, order the SAI50X300S. Verify the ISO 15552 mounting interface, 50mm bore, 300mm stroke, G1/4 port (PT/G/NPT) and your specific mounting accessory. The -S suffix means a piston magnet for CS1-B/DS1-B switches is present; without -S, no sensor can be fitted. Sizing both ways: a 40mm bore yields 628N push at 0.5MPa, while a 63mm bore yields 1559N. Note that a plain cylinder drifts on air loss as the cushion only decelerates; for load holding use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant. At 300mm stroke, prevent rod bending by guiding the load against side-load forces.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X300S
- ✓ 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 SI50X300S FAQ
Yes, the SI50X300S is discontinued. The direct replacement is the SAI50X300S. It is dimensionally interchangeable per ISO 15552, keeping the same 50mm bore, 300mm stroke, 982N force, G1/4 port and mounting interface.
The G1/4 port is fixed by the 50mm bore. At 0.5MPa it provides 982N push and 825N pull force. At 0.7MPa push is 1374N, and at 0.9MPa it is 1767N. The theoretical maximum force is 200kgf at 1.0MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X300S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X300S replacement — usually within 7-8 hours.