This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X690S, 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 SI50X690S
The AirTAC Airtac SI50 Standard Cylinder SI50X690S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 690mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X690S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke690 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X690S
- 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 SI50X690S
The AirTAC SI50X690S is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 690mm stroke. It delivers a push force of 982 N at 0.5 MPa via a G1/4 port. AirTAC replaced this legacy unit with the SAI50X690S, a direct upgrade retaining the exact ISO 15552 mounting interface, bore, stroke, force, port and mounting accessories.
The SAI replacement features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. The SAI family also introduces SAIL, SAIF and BSAI lock variants absent in the SI line. This -S model includes a piston magnet for legacy CS1-B/DS1-B sensors.
Airtac SI50 Standard Cylinder SI50X690S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X690S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X690S |
| Bore size | Ø50 mm |
| Stroke | 690 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 SAI50X690S 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 SAI50X690S 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 SI50X690S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×690 | 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 SI50X690S Is Used
Long-Stroke Diversion
Pushes packages across a 690mm transfer lane using the 982 N push force at 0.5 MPa, requiring external guides to prevent rod bending.
Pallet Stopper Arms
Acts as a 690mm extended stopper arm on roller conveyors, utilizing the G1/4 port and ISO 15552 mounting for rigid fixture integration.
Replacing the Airtac SI50 Standard Cylinder SI50X690S with the SAI50X690S
To replace the SI50X690S, order the SAI50X690S. Verify your ISO 15552 mounting interface (LB, FA, TC, etc.), the G1/4 air port, and the M16x1.5 rod thread. The -S magnet means it accepts CS1-B/DS1-B switches; the SAI replacement uses current AirTAC sensors. When sizing both ways, neighboring bores (40mm or 63mm) offer push forces of 628 N or 1559 N at 0.5 MPa. Because this is a 690mm stroke, use external guides to prevent rod bending and side-load damage. A plain cylinder drifts on air loss; for load holding, use an external pilot check valve or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X690S
- ✓ 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 SI50X690S FAQ
Yes, the SI50X690S is discontinued. The direct replacement is the AirTAC SAI50X690S. It shares the identical ISO 15552 mounting interface, 50mm bore, 690mm stroke, output force, G1/4 port and mounting accessories, fitting directly into existing fixtures.
This double-acting cylinder uses a G1/4 air port and provides a push force of 982 N and pull force of 825 N at 0.5 MPa. At 0.7 MPa the push force is 1374 N, and the theoretical maximum force is 200 kgf at 1.0 MPa. Operating speed is 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X690S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X690S replacement — usually within 7-8 hours.