This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X115S, 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 SI50X115S
The AirTAC Airtac SI50 Standard Cylinder SI50X115S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 115mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X115S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke115 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X115S
- 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 SI50X115S
The AirTAC SI50X115S is a discontinued double-acting ISO 15552 profile cylinder with a 50 mm bore and 115 mm stroke. It delivers 982 N push force at 0.5 MPa through a G1/4 port. AirTAC replaced this legacy unit with the SAI50X115S, a direct upgrade retaining the exact ISO 15552 mounting interface, bore, stroke, output force, and port size. The SAI features an upgraded piston seal with two Y-shaped one-way elements for lower start-up pressure and longer life. For position sensing, your -S model's built-in magnet works with legacy CS1-B/DS1-B switches, while the SAI replacement family uses current AirTAC sensors. The SAI line also introduces variants the SI lacked, including SAIL air-released locks and BSAI clamp-locks.
You can also customize the rod material (carbon steel, SUS420J2, or SUS304) and seals (Viton H raises the operating temperature to 0-150 C). Remember that a standard cylinder relies on live air; the adjustable 30 mm cushions only decelerate the piston near stroke end and will not hold a load during air loss.
Airtac SI50 Standard Cylinder SI50X115S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X115S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X115S |
| Bore size | Ø50 mm |
| Stroke | 115 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 SAI50X115S 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 SAI50X115S 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 SI50X115S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×115 | 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 SI50X115S Is Used
Package Diverting
Ideal for actuating routing gates on packaging lines where the 982 N push force easily redirects standard totes.
Light Pressing
Provides reliable downward pressure for seating bearings or pins, utilizing the 825 N pull force for safe retraction.
Pallet Stops
Deploys a 115 mm stroke stop block on roller conveyors to halt pallets precisely at a workstation.
Replacing the Airtac SI50 Standard Cylinder SI50X115S with the SAI50X115S
To replace your discontinued SI50X115S, order the SAI50X115S. Verify your ISO 15552 mounting accessory (LB foot, FA/FB flange, CA/CB clevis, or TC trunnion), the G1/4 air port thread (PT, G, or NPT), and the M16x1.5 rod-end connection. The -S suffix indicates a piston magnet for legacy CS1-B/DS1-B sensors, which carries over to the SAI family's current switch groove. When sizing, the 50 mm bore yields 982 N push and 825 N pull at 0.5 MPa; if you need less force, step down to a 40 mm bore (628 N push), or step up to a 63 mm bore (1559 N push) for heavier loads. Because the 115 mm stroke is under 300 mm, rod-bending side loads are minimal, but always guide the load externally. A plain SAI cylinder does not hold load without live air; for fail-safe holding, use the SAIL lock variant, BSAI clamp-lock, or an external pilot check valve.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X115S
- ✓ 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 SI50X115S FAQ
Yes, the SI50X115S is discontinued. The direct replacement is the AirTAC SAI50X115S. It shares the same ISO 15552 mounting interface, 50 mm bore, 115 mm stroke, output force, and G1/4 port, fitting directly into existing fixtures.
The 50 mm bore uses a G1/4 air port and an M16x1.5 rod thread. At 0.5 MPa it provides 982 N push and 825 N pull force. At 0.7 MPa push is 1374 N, and at 0.9 MPa it is 1767 N. The theoretical maximum force is 200 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X115S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X115S replacement — usually within 7-8 hours.