Knowledge | 2022-08-09

The positive and negative pressure of ultrasonic cleaning machine


In the ultrasonic cleaning process, the bubble will inhibit cavitation, and reduce the ability to clean. As long as the bubbles in the liquid are completely dragged away, the bubbles in the vacuum core group can achieve the effect, which is the role of degassing function. In addition, let's look at the three concepts of atmospheric pressure, positive pressure, and negative pressure: atmospheric pressure: refers to the atmospheric pressure, that is, the atmospheric pressure that we usually produce in this atmosphere. The atmosphere is 101,325 pa (Pascal-universal pressure unit). 100,000 pa = 100 kph, so “Atmosphere” is usually expressed in terms of 100 KPA or 101 kpa.

Positive Pressure: refers to the atmospheric pressure above the gas conditions. For example, when refueling a bicycle or car tire, the outlet end of the booster tube or pump generates positive pressure.

Negative pressure: refers to the state of gas below atmospheric pressure, also known as the“Vacuum.”. For example, when drinking from a tube, the tube is under negative pressure, and so is the suction cup used to suspend the object. The ultrasonic cleaner transmits the high-frequency vibration signal from the ultrasonic generator to the solvent through the transducer. The ultrasonic wave radiates forward in the cleaning liquid, causing the liquid to produce tens of thousands of small bubbles with a diameter of 50-500μm. The small bubbles in the ultrasonic cleaning machine also produce vibration under the action of the ultrasonic wave.

These bubbles form and grow in the negative pressure region of ultrasonic longitudinal propagation, while in the positive pressure region when the sound pressure reaches a certain value, the bubbles will actively increase and break up. An ultrasonic cleaning machine produces shock waves when air bubbles burst. This will destroy the insoluble dirt and strip it off into the cleaning solution of the ultrasonic cleaning equipment. When the group particles are coated by oil and adhered to the surface of the cleaning part, the oil will emulsify, separating the solid particles, and then achieve the goal of cleaning the part. In this process, known as the “Cavitation effect,” closed bubbles can form at temperatures as hot as Baidu, and can exceed 1,000 atmospheres. “Explosion” continuously impacts the surface of the object, so that the surface and the cracks in the dust and dirt fall, and then achieve the goal of cleaning and cleaning the surface of the object.

The positive and negative pressure of ultrasonic cleaning machine