This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50BX165, 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 SI50BX165
The AirTAC Airtac SI50 Standard Cylinder SI50BX165 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 165mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50BX165, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke165 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50BX165
- 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 SI50BX165
The AirTAC SI50BX165 is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 165mm stroke. It delivers a 982N push force at 0.5MPa via a G1/4 port. The direct replacement is the SAI50BX165, matching the interface, force, and mounting exactly.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. Note this SKU lacks a magnet (-S), so it cannot take CS1-B/DS1-B sensors; the -B rod option is SUS304 stainless.
Airtac SI50 Standard Cylinder SI50BX165 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50BX165 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50BX165 |
| Bore size | Ø50 mm |
| Stroke | 165 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 SAI50BX165 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 SAI50BX165 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 SI50BX165
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×165 | 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 SI50BX165 Is Used
Package Diverting
Actuates routing gates on packaging lines where the 982N push force easily overcomes friction to redirect 20kg cartons at 30-800 mm/s.
Clamp Actuation
Provides reliable clamping pressure for light machining fixtures, utilizing the 825N pull force to hold workpieces securely during drilling.
Vertical Lift Stops
Controls stopping mechanisms for 50kg vertical loads in material handling, operating safely within the 589N working load limit.
Replacing the Airtac SI50 Standard Cylinder SI50BX165 with the SAI50BX165
To replace the SI50BX165, order the SAI50BX165. Confirm the ISO 15552 mounting fixture (LB, FA, TC, etc.), the G1/4 port, and the M16x1.5 rod thread. Because this specific SKU has no magnet, it cannot accept position sensors; if switching is needed, order an SAI50BX165S. For sizing, the 50mm bore yields 982N push at 0.5MPa; dropping to a 40mm bore gives 628N, while a 63mm bore provides 1559N. A plain cylinder drifts on air loss—the cushion only decelerates—so use an external pilot check valve or the SAIL/BSAI lock variant for load holding. The 165mm stroke is under the 300mm threshold, so rod-bending side-load risks are minimal, but always guide the load.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50BX165
- ✓ 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 SI50BX165 FAQ
Yes, the SI50BX165 is discontinued. The direct replacement is the SAI50BX165. It is dimensionally interchangeable per ISO 15552, retaining the same 50mm bore, 165mm stroke, G1/4 port, and mounting interface, but adds an upgraded two Y-shaped one-way piston seal.
This 50mm bore cylinder uses a G1/4 air port. The thrust ratings 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.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50BX165
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50BX165 replacement — usually within 7-8 hours.