Surface / Interfacial tensiometer is an ideal device used to determine water (soil moisture) potential tension in the vadose zone. It’s widely used to inspect the insulation oil materials in irrigation works, electric power department; or research and education work in petroleum, chemical engineering, science academy.

Feature: TEN201 automatic operation, LED digit display, Measuring tray auto up and down; Automatic one key adjust Zero point function;   With peak value holding function; Automatic stop when the liquid film break.

Surface tension: To measure the surface tension between a liquid and the air, the Tensiometer duNouy ring is placed below the surface of the liquid. This test is performed by pulling the ring upward through the surface of the liquid. The force needed for the ring to break the surface (overcome the surface tension) is determined.

Interfacial tension: There are applications where the surface tension at the boundary of two liquids needs to be measured. This is called interfacial surface tension.
The Tensiometer for this test needs to pull the ring up through the boundary between the lower, higher density liquid, and the liquid that is floating above. The force needed to break through the surface of the higher density liquid is recorded as interfacial surface tension.The force needed to break the boundary going from the floating liquid to the greater density liquid is measured by pushing the ring down through the boundary.

Du Nouy ring method:  The du Nouy ring method is one technique by which the surface tension of a liquid can be measured. The method involves slowly lifting a ring, often made of platinum, from the surface of a liquid. The force required to raise the ring from the liquid's surface is measured and related to the liquid's surface tension.

Other name:
surface tension tester, liquid surface tension, surface tension of liquid, digital tension meter, ink surface tensiometer, Dunouy tensiometer, Du nouy platinum ring method, Interfacial tensiometer, Du nouy ring tester. 
 

Comparison:

ISO 304 "Surface active agents -- Determination of surface tension by drawing up liquid films”

ISO 1409  " Plastics/rubber -- Polymer dispersions and rubber latices (natural and synthetic) -- Determination of surface tension by the ring method”

ISO 6295  " Petroleum products -- Mineral oils -- Determination of interfacial tension of oil against water -- Ring method “

ASTM D1417  "Standard Test Methods for Rubber Latices—Synthetic”

ASTM D1590  "Surface tension of industrial water and Industrial waste water”

ASTM D1331  "Standard Test Methods for Surface and Interfacial Tension of Solutions of Paints, Solvents, Solutions of Surface-Active Agents, and Related Materials”

ASTM D971  "Standard Test Method for Interfacial Tension of Oil Against Water by the Ring Method”

EN 14370  "Surface active agents. Determination of surface tension”

EN14210, OECD 115, ZB2025, GB/T 2960, GB/T 6541, GB/T 22237, GB/T 6541, GB/T 5549 etc.,