Thermostatic Water Bath for Viscometers

Method

• A manual bath is used to determine the kinematic viscosity of transparent and opaque liquids.
• The time taken for a fixed volume of liquid to flow under gravity through a calibrated glass capillary of a viscometer at closely controlled and known temperature is measured.
• Kinematic viscosity (determined value) is the product of the measured flow time and the calibration constant of the viscometer. Two such determinations are needed to calculate a kinematic viscosity result which is the average of two acceptable determined values.
• A type of viscometer should be selected depending on the sample type and individual preferences.

Standards

• Standards: ASTM D445, ASTM D446, ASTM D1655, ASTM D2170, IP71, EN ISO 3104, ISO 3105, and DIN 51562.
• The test method defines the manual determination of kinematic viscosity.
• Measure the flow time of a volume of transparent or opaque liquid under gravity through a calibrated glass capillary viscometer (please refer to ASTM D445 and D446).

Manual Kinematic Viscometer Baths

Bath Temperature

• A bath at constant temperature is used.
• Temperature tolerance max. ±0.02°C between +15°C and +100°C. ±0.05°C outside this range.
• The temperature measuring device is a calibrated glass thermometer with accuracy of ±0.02°C or better. Or a Digital Contact Thermometer (DCT) is permitted. We recommend our E20 DCT thermometer for temperature. 20°C to +120°C range (P/N 19T4043)
• Since October 2017, the use of mercury in LIG thermometers has been banned in the European Union and the market must switch to DCTs.

Glass Capillary Kinematic Viscometer

• The viscometer is a calibrated capillary, the size depends on the sample being tested.
• Flow times between 200 and 900 seconds are recommended.
• The viscometer must be suspended in a vertical position. This is possible with stainless steel viscometer holders. These are available for most viscometers, see www.testform.com.tr for more information.

Timing Device Stopwatch

• Manual timing device allows readings with 0.1 second or better tolerance. Accuracy ±0.07%.
• Electric timing devices are used when ±0.05% or better precision is required.
• The timer uses a crystal with maximum 20 ppm (parts per million) deviation.
• In one second that is (1 / 1,000,000) * 20 = 0.00002 sec.
• One hour is 60*60*0.00002 = 0.072 seconds.
• Human reaction time is 0.2 seconds (200 mS).
• So when measuring one hour, timer error is three times less than human error (viscosity flow time is between 200 and 900 seconds).

TV2000 & TV4000 (Main Features)

• Temperature Range
• Ultra High Stability
• Three or Seven Places
• LED Lights Background
• Removable Front Window
• Bath Drain and Bath Overflow
• PID Digital Controller

Temperature Range

• Standard range from ambient temperature to +230°C.
• TV2000 and TV4000 are standard equipped with a cooling coil.
• Lower ambient temperatures can be reached when connected to tap water or an external chiller.