Surface Tension Instruments
Manual
Tensiometer
K6
Reliable laboratory instrument for accurate measurement of surface tension and interfacial tension using the Du Noüy Ring Method.
What sets it apart
Key Features
How it works
Du Noüy Ring Method
The Manual Tensiometer K6 is based on the Du Noüy Ring Method — one of the most widely used and trusted techniques for measuring surface tension and interfacial tension of liquids.
A platinum ring is carefully placed beneath the liquid surface. As the ring is slowly pulled upward, the instrument precisely measures the maximum force required to detach it from the surface — this force is directly proportional to the surface tension of the liquid.
This method is standardized under ASTM D971 and IS-6104, making it suitable for IFT measurement of transformer oil and water in power industry applications.
Position the Ring
Platinum-Iridium ring is submerged just below the liquid surface in the sample vessel.
Apply Torsion Force
The torsion wire mechanism slowly lifts the ring while measuring the applied force continuously.
Measure Detachment Force
The maximum force at the point of ring detachment from the liquid surface is recorded.
Read SFT / IFT Value
The dial displays surface tension or interfacial tension directly in mN/m — no correction required.
Where it's used
Applications
Technical details
Specifications
| Specification | Details |
|---|---|
| Instrument Type | Manual Tensiometer |
| Measurement Method | Du Noüy Ring Method |
| Ring Material (MOC) | Platinum-Iridium (Pt-Ir) |
| Ring Circumference | 59.97 mm |
| Ring Radius (R) | 9.545 mm |
| Measurement Range | 1 – 90 mN/m |
| Resolution | 1 mN/m |
| Results Displayed | Surface Tension (SFT), Interfacial Tension (IFT) |
| Footprint | 230 mm × 270 mm |
| Height | 315 mm |
| Weight | 3 kg |
Sectors served
Industries
Common questions