This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X500STC, 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 SI50X500STC
The AirTAC SI50 Standard Cylinder SI50X500STC is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 500mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X500STC, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke500 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X500STC
- 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 SI50X500STC
The AirTAC SI50X500STC is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 500mm stroke. It delivers 982N push force at 0.5MPa via a G1/4 port. The direct replacement is the SAI50X500STC, which retains the exact ISO 15552 mounting interface, TC trunnion mount, and M16x1.5 rod thread to fit existing fixtures.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and long life. For load holding, note that a standard cylinder drifts on air loss—the cushion only decelerates—so use an external rod lock or the SAIL/BSAI lock variants. This -S model includes a magnet for CS1-B/DS1-B sensors, while the SAI uses current AirTAC switches.
Airtac SI50 Standard Cylinder SI50X500STC Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X500STC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X500STC |
| Bore size | Ø50 mm |
| Stroke | 500 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 SAI50X500STC 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 SAI50X500STC 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 SI50X500STC
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×500 | 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 SI50X500STC Is Used
Long-Stroke Diverting
Ideal for pushing products across a 500mm lane on a packaging conveyor, utilizing the 982N force at 0.5 MPa to shift heavy cartons reliably.
Pallet Stopper Gate
Acts as a TC-mounted trunnion stop gate for pallets, providing a 50kg vertical lift margin and decelerating smoothly via its 30mm adjustable air cushions.
Component Ejection
Ejects machined parts from a fixture over a 500mm distance, where the CS1-B/DS1-B magnet sensors confirm the full extension position.
Replacing the Airtac SI50 Standard Cylinder SI50X500STC with the SAI50X500STC
To replace the discontinued SI50X500STC, order the SAI50X500STC. Confirm the ISO 15552 TC trunnion mounting, 50mm bore, 500mm stroke, G1/4 port, and the -S magnet for position sensing. The SAI family also adds SAIF (built-in valve) and BSAI (clamp-lock) options. If sizing down, a 40mm bore gives 628N push at 0.5MPa; sizing up to 63mm yields 1559N. Because the 500mm stroke exceeds 300mm, use an external guide to prevent rod bending and side-load wear. A plain cylinder does not hold load without live air; for drop prevention, specify the SAIL lock variant or a pilot check valve.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X500STC
- ✓ 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 SI50X500STC FAQ
Yes, the AirTAC SI50X500STC is discontinued. The direct replacement is the SAI50X500STC. It is dimensionally interchangeable per ISO 15552, retaining the same 50mm bore, 500mm stroke, G1/4 port, and TC mounting interface.
The bore is 50mm with a G1/4 air port. Force output is 982N push and 825N pull at 0.5 MPa, 1374N push at 0.7 MPa, 1767N push at 0.9 MPa, and a theoretical max of 200 kgf at 1.0 MPa. Speed is 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X500STC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X500STC replacement — usually within 7-8 hours.