This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50BX65, 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 SI50BX65
The AirTAC Airtac SI50 Standard Cylinder SI50BX65 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 65mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50BX65, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke65 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50BX65
- 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 SI50BX65
The AirTAC SI50BX65 is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore, 65mm stroke, and G1/4 port. It delivers 982N push and 825N pull at 0.5MPa. The direct replacement is the SAI50BX65, which maintains the exact same interface, force, and mounting dimensions.
This SAI upgrade features a new piston seal with two Y-shaped one-way elements for low start-up pressure and long life. Note this SKU lacks a magnet, so it cannot take a sensor; the SI used CS1-B/DS1-B switches. The -B rod is SUS304 stainless.
Airtac SI50 Standard Cylinder SI50BX65 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50BX65 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50BX65 |
| Bore size | Ø50 mm |
| Stroke | 65 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 SAI50BX65 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 SAI50BX65 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 SI50BX65
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×65 | 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 SI50BX65 Is Used
Mid-Force Clamping
Ideal for holding medium workpieces during machining, using its 982N push force at 0.5 MPa to secure parts firmly against fixtures.
Short-Stroke Diverting
The 65mm stroke provides precise actuation for routing or stopping packages on a production line without taking up excessive space.
Stainless Rod Ejection
The SUS304 rod option excels in humid washdown environments, pushing finished goods out of machinery without corroding.
Replacing the Airtac SI50 Standard Cylinder SI50BX65 with the SAI50BX65
To replace the SI50BX65, order the SAI50BX65. Confirm the ISO 15552 mounting interface, G1/4 port, and 65mm stroke. Because this SKU has no -S magnet, it cannot support sensing; if position detection is needed, order an SAI50X65S instead and use current AirTAC switches. For sizing down, a 40mm bore gives 628N push; sizing up to 63mm yields 1559N. A plain cylinder drifts on air loss—the cushion only decelerates—so for load holding use an external pilot check valve or the SAIL/BSAI lock variants. The SUS304 rod option suits corrosive settings.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50BX65
- ✓ 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 SI50BX65 FAQ
Yes, the SI50BX65 is discontinued. The direct replacement is the SAI50BX65. It is dimensionally interchangeable per ISO 15552, retaining the same 50mm bore, 65mm stroke, G1/4 port, and mounting fixtures.
It features a G1/4 air port. The thrust 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 maximum of 200 kgf at 1.0 MPa.
Request a Quote for the SAI50BX65
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50BX65 replacement — usually within 7-8 hours.