This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAID50X85S, 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 SID Series Double-Rod Cylinder SID50X85S
The AirTAC Airtac SID Series Double-Rod Cylinder SID50X85S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 85mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAID50X85S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke85 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAID50X85S
- 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 SID Series Double-Rod Cylinder SID50X85S
The AirTAC SID50X85S is a double-acting, double-rod ISO 15552 cylinder where a rod exits both ends, ensuring force is equal both ways (825 N at 0.5 MPa). This discontinued model drops directly into the SAID50X85S replacement, reusing the exact G1/4 port, M16x1.5 rod thread, and ISO 15552 mounting interface without bracket changes.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. The back rod can drive a second tool or carry a sensor cam for synchronized positioning. The -S suffix provides a piston magnet for legacy CS1-B/DS1-B switches.
Airtac SID Series Double-Rod Cylinder SID50X85S Technical Specifications
| Model | Airtac SID Series Double-Rod Cylinder SID50X85S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAID50X85S |
| Bore size | Ø50 mm |
| Stroke | 85 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 SAID50X85S 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 SAID50X85S produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SID Series Double-Rod Cylinder SID50X85S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×85 | 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 SID Series Double-Rod Cylinder SID50X85S Is Used
Synchronized Tool Driving
Uses the extended back rod to drive a secondary mechanism or tool simultaneously with the front, maintaining equal force and timing.
Anti-Rotation Workholding
The dual-rod geometry prevents piston twist during clamping, ensuring precise angular alignment for machining or gauging.
External Cam Positioning
Mounts a sensor cam on the rear rod to trigger legacy CS1-B/DS1-B switches without occupying space on the primary working end.
Replacing the Airtac SID Series Double-Rod Cylinder SID50X85S with the SAID50X85S
To replace the discontinued SID50X85S, specify the SAID50X85S, which matches the 50mm bore, 85mm stroke, G1/4 port, and FA/LB/TC mounting footprint. Because force is equal both ways, size both extend and retract motions identically; if 825 N at 0.5 MPa is borderline, step up to the 63mm bore (1402 N) or down to the 40mm bore (528 N). A double rod is correct when you need anti-rotation resistance or a cam on the rear. Retain the -S magnet option for sensing. For this 85mm stroke side-load is minimal, but for strokes >=300mm ensure guide alignment to prevent binding.
Replacement checklist
- ✓ Same ISO 15552 interface → SAID50X85S
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SID Series Double-Rod Cylinder SID50X85S FAQ
Yes, the SID50X85S is discontinued. The direct replacement is the SAID50X85S. It shares the same ISO 15552 interface, 50mm bore, 85mm stroke, G1/4 port, and mounting brackets, but adds an upgraded two Y-shaped one-way piston seal.
Force is equal both ways: 825 N at 0.5 MPa, 1154 N at 0.7 MPa, and 1484 N at 0.9 MPa. Operating pressure is 0.15-1.0 MPa, speed is 30-800 mm/s, and it uses a G1/4 air port with 30mm adjustable cushions at each end.
Related AirTAC SAI Cylinders
Request a Quote for the SAID50X85S
Send us the quantity and destination. We confirm price, stock and lead time on the SAID50X85S replacement — usually within 7-8 hours.