Bimetallic thermometer to charge the difference between oil and no oil filled in where?

Oil filled bimetallic thermometer and the difference between ordinary bimetallic thermometer is mainly manifested in the structure of the different. Oil filled bimetallic thermometer as the name implies header internal filling liquid, main purpose is to reduce the external vibration environment disturbance to the pointer, achieve the goal of ensure the sensitivity of the thermometer. Because of its seismic characteristic, also known as seismic bimetallic thermometer. Sealing structure, pan sides or rear oil filled with a hole, see below, instrument production of oil-extended thermometer is sump oil filled with a hole side, convenient and glycerin or silicone oil filling, because the relationship between the two kinds of oil to the boiling point, usually applies to range under 150 ℃. Instead of oil-extended bimetallic thermometer, namely common bimetallic thermometer, no oil filled with a hole, apply to the ordinary place, can be measured medium for - The temperature between 40 + 500 ℃. Price, oil filled bimetallic thermometer than ordinary bimetallic thermometer more expensive.