Gas Stove Flame
For security needs, flameout protection device for gas stoves are very necessary, relevant national standards are also mandatory.
Flameout protection there are three commonly used on the market: thermal, thermal type and the photoelectric type.
Thermal: also known as bi-metal type. Bimetallic Strip is composed of two different expansion coefficients of the metal, and in the presence of temperature, expansion coefficient of metal to the expansion coefficient of metal bending, when you lose temperature, the original expansion bend metal and will slowly return to its original state, so double-sheet metal, also known as shape memory alloy. The double sensor of the metal plate used as a safety device, is the use of double bending of sheet metal under the action of temperature expansion properties.
Bimetallic protection device has the advantage of simple structure, low cost. Disadvantage is installation difficult, installation location of the bimetal Strip and plug valves and gas valve fits all have very high demands, and a large thermal inertia, opening and closing valve of long and short service life.
Heat type: the device is using the heat generated during combustion of the gas.
Thermoelectric flame failure safety device by thermocouples and solenoid valve consists of two parts, the thermocouple is formed by the combinations of two different kinds of alloy materials. Different alloys at temperatures under different thermal potential, the thermocouple is the use of different alloys materials in thermoelectric power of temperature under different made, it took advantage of poor heating value of different alloy.
Thermoelectric safety device is simple in structure, easy installation, low cost and have been widely used. But this kind of protection device with thermocouple as a heat sensor, disadvantage is the large thermal inertia, slow response, making a person feel inconvenient and short service life, plug valves and solenoid valves mounted high precision.