This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X525S, 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 SI50X525S
The AirTAC SI50 Standard Cylinder SI50X525S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 525mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X525S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke525 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X525S
- 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 SI50X525S
The AirTAC SI50X525S is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 525mm stroke. Delivering 982N push force at 0.5MPa via a G1/4 port, it is replaced by the SAI50X525S. This direct upgrade shares identical ISO 15552 mounting interface dimensions, stroke and output force.
The SAI features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life. The SAI family also adds SAIL, SAIF and BSAI lock variants the SI lacked. Your -S magnet works with legacy CS1-B/DS1-B sensors.
Airtac SI50 Standard Cylinder SI50X525S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X525S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X525S |
| Bore size | Ø50 mm |
| Stroke | 525 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 SAI50X525S 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 SAI50X525S 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 SI50X525S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×525 | 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 SI50X525S Is Used
Long-Stroke Diversion
Pushes packages across a 525mm conveyor lane transfer using 982N of thrust at 0.5MPa.
Multi-Station Indexing
Shifts a tooling carriage between machining stations over a 525mm distance with adjustable cushions.
Replacing the Airtac SI50 Standard Cylinder SI50X525S with the SAI50X525S
To replace the SI50X525S, order the SAI50X525S. Verify the ISO 15552 mounting accessory (LB, FA, TC), the G1/4 port thread (PT/G/NPT) and the -S magnet for CS1-B/DS1-B switches. The SAI is dimensionally interchangeable per ISO 15552. Sizing both ways: a 63mm bore gives 1559N push at 0.5MPa, while a 40mm bore yields 628N. At 525mm, prevent rod bending by using external guides to manage side loads. A plain cylinder drifts without air; for load holding use the SAIL lock variant or a pilot check valve.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X525S
- ✓ 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 SI50X525S FAQ
Yes, the SI50X525S is discontinued. The direct replacement is the SAI50X525S. It shares the same ISO 15552 mounting interface, 50mm bore, 525mm stroke, output force and G1/4 port, fitting existing fixtures perfectly.
The 50mm bore uses a G1/4 port. Force output is 982N push and 825N pull at 0.5MPa, 1374N push at 0.7MPa, 1767N push at 0.9MPa, and a theoretical max of 200kgf at 1.0MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X525S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X525S replacement — usually within 7-8 hours.