This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X850SN, 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 SI50X850SN
The AirTAC SI50 Standard Cylinder SI50X850SN is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 850mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X850SN, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke850 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X850SN
- 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 SI50X850SN
The AirTAC SI50X850SN is a discontinued double-acting ISO 15552 profile cylinder with an extruded aluminum barrel, delivering a push force of 982 N at 0.5 MPa. It features a 50 mm bore, 850 mm stroke, G1/4 port, M16x1.5 rod thread, and a built-in magnet for CS1-B/DS1-B switches. The NBR seal supports -20 to +70 C. AirTAC replaced this legacy unit with the SAI50X850SN, a direct sharing the exact ISO 15552 mounting interface, bore, stroke, output force, and port size.
The SAI upgrade introduces a refined piston seal using two Y-shaped one-way elements for lower start-up pressure and longer life. Note that a plain cylinder drifts on air loss; the cushion only decelerates near stroke end. For load holding, explore the SAIL or BSAI lock variants, or use an external pilot check valve.
Airtac SI50 Standard Cylinder SI50X850SN Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X850SN |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X850SN |
| Bore size | Ø50 mm |
| Stroke | 850 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 SAI50X850SN 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 SAI50X850SN 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 SI50X850SN
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×850 | 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 SI50X850SN Is Used
Long-Stroke Material Push
Ideal for transferring products across a 850 mm gap on a conveyor line, utilizing the 982 N push force at 0.5 MPa to index cardboard cartons or sheet materials reliably.
Extended Reach Actuators
Deploys tooling or fixtures over an 850 mm reach where external guides manage side loads, taking advantage of the adjustable 30 mm air cushions at both ends for smooth stops.
Replacing the Airtac SI50 Standard Cylinder SI50X850SN with the SAI50X850SN
To replace the SI50X850SN, order the SAI50X850SN direct equivalent, verifying the ISO 15552 mounting interface, G1/4 port (PT/G/NPT), 50 mm bore, 850 mm stroke, NBR seal, and the -S magnet for current AirTAC switches. When sizing, a 40 mm bore offers 628 N push at 0.5 MPa, while a 63 mm bore provides 1559 N; this 50 mm bore yields 982 N. Because the 850 mm stroke is long, prevent rod bending by ensuring external guides absorb side loads. A standard cylinder does not hold load without live air—the cushion only decelerates. For secure holding, use an external rod lock, a pilot check valve, or the SAIL/BSAI lock variants. The SAIF variant adds a built-in 4M valve if needed.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X850SN
- ✓ 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 SI50X850SN FAQ
Yes, the AirTAC SI50X850SN is discontinued. The direct replacement is the SAI50X850SN. It is dimensionally interchangeable per ISO 15552, retaining the same 50 mm bore, 850 mm stroke, 982 N force, G1/4 port, and mounting interface to fit existing fixtures directly.
This double-acting cylinder has a G1/4 air port. The thrust ratings are 982 N push and 825 N pull at 0.5 MPa, 1374 N push at 0.7 MPa, 1767 N push at 0.9 MPa, and a theoretical maximum force of 200 kgf at 1.0 MPa. Operating speed is 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X850SN
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X850SN replacement — usually within 7-8 hours.