Dropping / Softening Point Apparatus

A digital melting dropping instrument uses a furnace and video camera to automatically detect the drop point and softening point event. This measurement is done digitally, reducing operator influence considerably. Two samples can be measured simultaneously with a temperature accuracy of down to 0.2 °C and short heating and cooling times. The layout of the furnace and the video image analysis respectively allow two samples to be measured simultaneously. METTLER TOLEDO Excellence Dropping Point Systems DP70 and DP90 work both as automated dropping point apparatuses and automated softening point apparatuses.

Click here to learn everything you need to know about softening and dropping point measurements

A METTLER TOLEDO dropping point system is represented in the schematic diagram below.

This system is a combination of a furnace and a video camera.

Dropping point and softening point is determined by heating the sample. The furnace is used to control the temperature during an analysis. Temperature control and recording is ensured by a digital platinum sensor.

In the Dropping Point Excellence Systems from METTLER TOLEDO, a white balanced LED light is shining on the test assembly, which consists of the cup and holder inside the furnace. The reflection image is recorded by a video camera.

For the automated dropping point determination, the entire drop point test is video-recorded and image analysis is used to detect the first drop that escapes the sample cup when it passes through a virtual white rectangle located underneath the cup orifice. While detecting this, the furnace temperature is measured and recorded at a resolution of 0.1 °C.

For the automated softening point determination, the leading edge of the softened sample is marked with a stepping line in the video. Once the stepping line has passed a virtual line that is located 19 mm below the cup orifice the corresponding furnace temperature is measured and recorded at a resolution of 0.1 °C.

Dropping point testers are used to determine the dropping and softening points of ointments, synthetic and natural resins, rosins, edible fats, greases, waxes, fatty acid esters, pitch, asphalt, tars, bitumen, and many more materials.

Get useful tips and hints for correct sample preparation of different dropping point and softening point samples.

Edible oils, fats and organic solvents can be solidified and measured at low temperatures. Substances often need to be cooled or frozen for a sufficient amount of time prior to the dropping point measurement. The METTLER TOLEDO Excellence Dropping Point System DP90 performs dropping point measurements down to -20 °C. Place the separate DP90 measurement cell, the furnace and the optical detection system, in a refrigerator or a freezer till the required temperature is attained.

The METTLER TOLEDO dropping point instruments fully comply with the following standards for dropping point and softening point determination:

• ASTM D3104 for automatic softening point determination of pitches
  
• ASTM D3461 for automatic softening point determination of bitumen, pitch and asphalt
  
• ASTM D3954 for automatic dropping point tests of waxes
  
• ASTM D6090 for automatic softening point determination of resins
  
• AOCS Cc 18-80 for automatic dropping point detection of edible fats and edible oils
  
• European Pharmacopeia Ph.Eur. 2.2.17 for drop point
  
• IP 396 for automatic dropping point detection of lubricating grease
  
• ISO 4625 for softening point determination of paints and varnishes
  
• DIN EN 51920 for softening point determination of carbonaceous material
  

International standards ASTM D3104, ASTM D3461, ASTM D3954, ASTM D6090 and AOCS Cc 18-80 are specifically based on automatic dropping point and softening point determinations made on METTLER TOLEDO instruments.