This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X50FA, 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 SI50X50FA
The AirTAC Airtac SI50 Standard Cylinder SI50X50FA is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 50mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X50FA, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke50 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X50FA
- 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 SI50X50FA
The AirTAC SI50X50FA is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 50mm stroke. It delivers 982N push force at 0.5MPa via a G1/4 port. The direct replacement is the SAI50X50FA, which shares the same FA flange mounting, M16x1.5 rod thread, and 30mm cushions.
This SAI upgrade features a new piston seal with two Y-shaped one-way elements for low start-up pressure. Since this specific SI SKU lacks the -S magnet, it cannot accept position switches like the legacy CS1-B/DS1-B sensors. The SAI family also adds SAIL and BSAI lock variants absent from the SI line.
Airtac SI50 Standard Cylinder SI50X50FA Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X50FA |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X50FA |
| Bore size | Ø50 mm |
| Stroke | 50 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 SAI50X50FA 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 SAI50X50FA 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 SI50X50FA
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×50 | 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 SI50X50FA Is Used
Clamping Fixtures
Applies 982N of clamping thrust at 0.5MPa for securing mid-weight machined components during milling or drilling operations.
Package Diverting
Short 50mm stroke actuation for pushing moderate cartons off a main conveyor belt line onto secondary packaging lanes.
Pallet Stop Gates
Raises and lowers physical stop gates to control pallet flow on roller conveyors, utilizing the FA flange for rigid mounting.
Replacing the Airtac SI50 Standard Cylinder SI50X50FA with the SAI50X50FA
To replace the SI50X50FA, order the SAI50X50FA. It is dimensionally interchangeable per the ISO 15552 mounting interface, matching the 50mm bore, 50mm stroke, G1/4 port, and FA flange accessory. When sizing, neighboring bores offer alternatives: the 40mm bore yields 628N push at 0.5MPa, while the 63mm bore provides 1559N. Remember that a plain cylinder does not hold load on air loss; the cushions only decelerate. For load holding, use an external pilot check valve or explore the SAIL lock variant. If your fixture requires position sensing, select an SAI model with the -S magnet option, as this no-S SKU cannot take a sensor.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X50FA
- ✓ 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 SI50X50FA FAQ
Yes, the SI50X50FA is discontinued. The direct replacement is the SAI50X50FA. It is dimensionally interchangeable per ISO 15552, retaining the same 50mm bore, 50mm stroke, G1/4 port, FA flange mount, and 982N force. You simply order the SAI equivalent.
This double-acting cylinder uses a G1/4 air port. The thrust figures are 982N push and 825N pull at 0.5MPa, 1374N push at 0.7MPa, 1767N push at 0.9MPa, and a theoretical maximum of 200kgf at 1.0MPa. It operates at speeds of 30-800mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X50FA
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X50FA replacement — usually within 7-8 hours.