When the mocha pot is heated, the air pressure in the kettle will rise, so there are two ways to relieve the pressure.

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The structure of the mocha pot is not complicated. The body of the mocha pot is divided into three parts: the bottom pot (A) contains water, and when the mocha pot is heated, the air pressure of the lower pot rises, pushing hot water rises through the diversion tube, permeates the powder trough (B) containing coffee powder for extraction, and finally rises to the top and flows into the upper pot (C). However, there is an important structure on the mocha kettle called the safety valve, which is used to vent air. When the mocha kettle is heated, the pressure in the kettle will rise, so there are two ways to relieve the pressure, either through the coffee powder layer, or if the pressure exceeds the safety threshold, to relieve pressure from the safety valve.

Therefore, please pay attention to add water can not miss the safety valve, if the safety valve is not passed by water, it means that the relief effect of the safety valve is discarded, the result is: 1. The pressure is high, the water passes through the coffee powder layer quickly, and the coffee liquid comes out of the tube directly. The pressure is high, and the coffee powder is tightly pressed, and the pressure relief is blocked. The upper pot and the lower pot are opened by air pressure. Ha, the mocha pot is fried, and it is not very hot, just 100 degrees liquid.

First of all, the metal tube at the end of the powder trough is coaxial and the same diameter as the metal tube in the center of the upper seat, which is designed to make the water flow in a straight line. When the water in the lower seat reaches a certain temperature, driven by pressure, the hot water will be pressed up from the metal tube at the end of the powder trough, through the coffee powder in the powder trough, and then filtered through the filter at the bottom of the upper seat. under pressure, the coffee liquid overflowed from the metal tube in the center of the upper seat. In this way, the process of coffee extraction is finished in principle.

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