This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI80X685S, 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 SI80 Standard Air Cylinder SI80X685S
The AirTAC SI80 Standard Air Cylinder SI80X685S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø80mm bore and 685mm stroke, G3/8 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI80X685S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ80 mm
- Stroke685 mm
- Port sizeG3/8
- Acting typeDouble acting
- Rod threadM20×1.5
- StatusDiscontinued → SAI80X685S
- 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 SI80 Standard Air Cylinder SI80X685S
The AirTAC SI80X685S is a discontinued double-acting ISO 15552 profile cylinder with an 80 mm bore, delivering 2513 N push and 2268 N pull at 0.5 MPa. AirTAC replaced this end-of-life unit with the SAI80X685S. It is a direct upgrade: identical bore, 685 mm stroke, G3/8 port, M20x1.5 rod thread, and ISO 15552 mounting interface, fitting existing fixtures perfectly. The SAI uses an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life.
This -S model includes a piston magnet for legacy CS1-B/DS1-B sensors (the SAI uses current AirTAC switches). You can also specify Viton H seals for 0-150 C heat, or SUS304 rod material. Note that a plain cylinder drifts on air loss; the 36 mm cushions only decelerate. For held loads, use the SAIL lock or BSAI clamp-lock variants.
Airtac SI80 Standard Air Cylinder SI80X685S Technical Specifications
| Model | Airtac SI80 Standard Air Cylinder SI80X685S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI80X685S |
| Bore size | Ø80 mm |
| Stroke | 685 mm |
| Acting type | Double acting |
| Port size | G3/8 |
| Rod thread | M20×1.5 |
| 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, 36 mm |
| Max standard stroke | Up to 1500 mm |
Specifications follow the official AirTAC SI datasheet (now discontinued). The SAI80X685S carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
Theoretical Output Force (Ø80mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 2513 N | 2268 N |
| 0.7 MPa | 3519 N | — |
| Max (@1.0 MPa) | 513 kgf | |
The SAI80X685S produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SI80 Standard Air Cylinder SI80X685S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 80 | Bore size in mm. |
| ×685 | 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 SI80 Standard Air Cylinder SI80X685S Is Used
Pallet Diversion
Pushes heavy pallets sideways onto parallel conveyor lines using the 2513 N push force at 0.5 MPa, while the 685 mm stroke clears adjacent guide rails.
Long-Reach Clamping
Extends 685 mm to secure large fabricated weldments inside a machining fixture, relying on the 36 mm adjustable air cushions to decelerate the payload.
Replacing the Airtac SI80 Standard Air Cylinder SI80X685S with the SAI80X685S
To replace the SI80X685S, order the SAI80X685S. Verify your ISO 15552 mounting accessory (LB, FA, TC, etc.), the G3/8 port threads, and the M20x1.5 rod end. Because this is a 685 mm stroke, prevent side-load and rod-bending by using an external guide to absorb lateral forces. Size both ways: if force is tight, the 100 mm bore offers 3927 N push @0.5 MPa; if downsizing, the 63 mm bore provides 1559 N. This -S SKU uses a magnet for CS1-B/DS1-B switches. A plain cylinder does not hold load without live air—the cushion only decelerates. For load holding on air loss, specify the SAIL air-released lock, BSAI clamp-lock, or an external pilot check valve.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI80X685S
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SI80 Standard Air Cylinder SI80X685S FAQ
Yes, the SI80X685S is discontinued. The direct replacement is the AirTAC SAI80X685S. It shares the identical ISO 15552 mounting interface, 80 mm bore, 685 mm stroke, output force, and G3/8 port, fitting your existing fixtures without modification.
The bore is 80 mm with a G3/8 air port and M20x1.5 rod thread. Force ratings are: 2513 N push and 2268 N pull at 0.5 MPa; 3518 N push at 0.7 MPa; 4523 N push at 0.9 MPa; and a theoretical max of 513 kgf at 1.0 MPa. Speed is 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI80X685S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI80X685S replacement — usually within 7-8 hours.