This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X520, 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 SI50X520
The AirTAC Airtac SI50 Standard Cylinder SI50X520 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 520mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X520, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke520 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X520
- 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 SI50X520
The AirTAC SI50X520 is a discontinued double-acting ISO 15552 profile cylinder with a 50 mm bore and 520 mm stroke, delivering 982 N push force at 0.5 MPa. The direct replacement is the SAI50X520, matching the exact G1/4 port, M16x1.5 rod thread and 30 mm cushions. Because this SKU lacks the -S magnet, it 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. If high heat is a factor, a Viton H seal raises the operating ceiling to 150 C.
Airtac SI50 Standard Cylinder SI50X520 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X520 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X520 |
| Bore size | Ø50 mm |
| Stroke | 520 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 SAI50X520 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 SAI50X520 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 SI50X520
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×520 | 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 SI50X520 Is Used
Pallet Stopper Gate
Acts as a 520 mm travel barrier to halt pallets, requiring an external pilot check valve to hold the load securely.
Replacing the Airtac SI50 Standard Cylinder SI50X520 with the SAI50X520
To replace the SI50X520, order the SAI50X520 to retain the identical ISO 15552 mounting interface, 50 mm bore, 520 mm stroke and G1/4 port. Confirm your mounting accessory (LB foot, FA flange, TC trunnion) and thread type (PT, G or NPT). Since this is a non-magnet SKU, you cannot mount legacy CS1-B or DS1-B sensors; order an -S variant if sensing is required. When sizing, the 40 mm bore offers 628 N push at 0.5 MPa, while the 63 mm bore provides 1559 N. Note that a plain cylinder drifts without live air; for load holding, use an external pilot check valve or the SAIL lock variant. Finally, at 520 mm stroke, prevent rod bending by using an external guide to absorb side loads.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X520
- ✓ 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 SI50X520 FAQ
Yes, the SI50X520 is discontinued. The direct replacement is the SAI50X520, which matches the ISO 15552 mounting interface, 50 mm bore, 520 mm stroke, output force and G1/4 port. It fits directly into existing fixtures.
The G1/4 port bore delivers a push of 982 N and pull of 825 N at 0.5 MPa. At 0.7 MPa the push is 1374 N, and the theoretical maximum force is 200 kgf at 1.0 MPa. The speed range is 30-800 mm/s.
Request a Quote for the SAI50X520
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X520 replacement — usually within 7-8 hours.