This method is suitable to measure the transparency of transformer oil and steam turbine oil.

1. Instrument:

(1) The inner diameter of test tube is 15±1mm. 

(2) Thermometer   -20℃-50℃.

2. Test procedures:

Inject the oil for trial into the dry test tube, if is transformer oil, it shall be cooled to 5℃; if it is steam turbine oil. It shall be cooled to 0℃. Then line the back of test tubes with white paper and black paper respectively. If it is observed at a place full of light that there is npt turbid phenomenon respectively, the oil for trial is thought to be transparent.