This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X900SN, 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 SI50X900SN
The AirTAC SI50 Standard Cylinder SI50X900SN is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 900mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X900SN, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke900 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X900SN
- 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 SI50X900SN
The AirTAC SI50X900SN is a discontinued double-acting ISO 15552 profile cylinder featuring a 50mm bore and 900mm stroke. It delivers 982N push force at 0.5MPa via a G1/4 port. AirTAC replaced this legacy unit with the SAI50X900SN, a direct upgrade retaining the exact interface, stroke, and force.
The SAI replacement upgrades the piston seal with two Y-shaped one-way elements for low start-up pressure. The SAI family also adds SAIL and BSAI lock variants lacking in the SI line.
Airtac SI50 Standard Cylinder SI50X900SN Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X900SN |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X900SN |
| Bore size | Ø50 mm |
| Stroke | 900 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 SAI50X900SN 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 SAI50X900SN 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 SI50X900SN
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×900 | 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 SI50X900SN Is Used
Long-Stroke Diversion
Pushes packages across a 900mm transfer belt with 982N force, utilizing the adjustable cushion to decelerate smoothly at full extension.
Automated Door Actuation
Opens large industrial machine guard doors over a 900mm span, relying on the NBR seals for standard -20 to +70 C operating environments.
Replacing the Airtac SI50 Standard Cylinder SI50X900SN with the SAI50X900SN
To replace the SI50X900SN, order the SAI50X900SN. Verify the ISO 15552 mounting interface, G1/4 port, M16x1.5 rod thread, and NBR seals. The -S magnet works with legacy CS1-B/DS1-B sensors, while the SAI uses current AirTAC switches. Neighbouring bores: a 40mm bore yields 628N push at 0.5MPa, whereas a 63mm bore yields 1559N. A plain cylinder drifts without live air; for load holding, use an external pilot check valve or the SAIL lock variant. Because the 900mm stroke exceeds 300mm, add external guides to prevent rod bending and side-load wear.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X900SN
- ✓ 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 SI50X900SN FAQ
Yes, the SI50X900SN is discontinued. The direct replacement is the SAI50X900SN. It shares the same ISO 15552 mounting interface, 50mm bore, 900mm stroke, output force, and G1/4 port, fitting existing fixtures perfectly.
It features a G1/4 air port and provides 982N push / 825N pull at 0.5MPa, 1374N push at 0.7MPa, and a theoretical maximum of 200 kgf at 1.0 MPa. The piston rod is 20mm with an M16x1.5 thread.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X900SN
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X900SN replacement — usually within 7-8 hours.