Background
Combustible gas detection alarm can be seen everywhere in our life, but the explosion caused by flammable gas leakage is so terrible that you understand it. Today, let’s walk into combustible gas and combustible gas detection
How long does it take for a gas leak to cause a violent explosion? The answer is 20 minutes.
Many people think it takes hours from the moment the gas starts leaking to the moment it meets a spark and explodes, but scientific tests by the fire department have proved that the process takes only 20 minutes.
The researchers set up a four-square-metre temporary hut with a gas range and a domestic fuel tank. Then the experimenter simulated a gas hose leak, a gas leak, and 20 minutes later, you could smell the concentration of the surrounding gas. Then, the experimenter lit a fire and the house exploded, lifting it more than half a meter into the air with the force of the explosion, shattering all the glass, breaking a window and breaking a wall. Thus, the explosive power of combustible gas is very large. If it happened in real life, it’s hard to imagine what terrible consequences would happen.
What are combustible gas sensors
Combustible gas refers to the substance that can ignite and is in gas state at room temperature and pressure. Such as hydrogen, acetylene, ethylene, ammonia, hydrogen sulfide and so on. Combustible gases have the general properties of gases. A combustible gas of one component is called a single gas; A mixture of two or more combustible gases is called a mixed combustible gas. Combustible gas in the corresponding combustion-supporting medium, in accordance with a certain proportion of mixing, under the action of ignition source, can cause combustion or explosion. Combustible gas is ejected from the nozzle at a certain velocity, and its combustion rate depends on the diffusion rate of combustible gas and air.
There’s a lot of flammable gas, Such as hydrogen (H2), carbon monoxide (CO), methane (CH4), ethane (C2H6), propane (C3H8), butane (C4H10), ethylene (C2H4), propylene (C3H6), butene (C4H8), acetylene (C2H2), proacetylene (C3H4), butyne (C4H6), hydrogen sulfide (H2S), phosphine ( PH3) etc.
Causes of gas leakage
The harm of gas explosion is so serious that the first thing to prevent gas explosion is to prevent gas leakage. From the factors causing gas leakage, hose problems account for 44%, hose aging, not connected, falling off is the primary factor leading to gas leakage; Forget to close or not completely close the valve accounted for 15%; Improper replacement or maintenance of liquefied gas tank leakage causes accounted for 14%. The above constitute the “three SINS” of gas leakage and gas explosion.
If we can monitor the gas leakage in the first time and solve it in the fastest time. We can prevent the gas explosion from happening, so that we can not only prevent the house from becoming a ruin, but also avoid serious casualties.
1 second warning, prevent gas explosion
Combustible Gas sensor
Combustible gas alarm mainly has catalytic combustion, thermal conductivity, infrared absorption and semiconductor type, among which the most widely used is catalytic combustion type. Catalytic combustion alarm sensor is mainly composed of bridge circuit, gas sensitive elements. When combustible gas enters the alarm probe, the oxidation reaction between gas and oxygen in the air occurs, and smokeless catalytic combustion occurs on the surface of platinum wire, resulting in temperature rise of platinum wire.
Platinum wire is a temperature sensitive element, and its resistance value increases with temperature rise. Bridge circuit loses balance and generates current, which converts the gas concentration value into electrical signal output. The alarm is composed of a detector and a controller. The detector is the probe sensor part, which converts the gas concentration into electrical signals. The controller includes control circuit, amplification circuit, alarm system and display.
In the past, we mainly rely on manpower to check gas leakage, which is difficult to work 24 hours a day, and many hidden dangers can not be monitored by the naked eye and nose. With the development of science and technology, it has become an irresistible trend to use Internet of things early warning technology to prevent gas explosion.
Take JXCT’s independently developed combustible gas sensor as an example. When it detects gas concentration in the air beyond the normal range, it immediately sends the signal to iot base stations and early warning platforms. It takes only one second for the platform to send a message via phone or other means, so users can be notified immediately even if they are not at home.
Selection of standard gas for verification:
Combustible gas detection alarm can use in different environments, and the types of combustible gas detected are different. Suitable standard gas should be selected for alarm verification to ensure the accuracy of quantity transfer. Standard gas should follow the following principles:
(1) Select the same standard gas as the type of gas detected by the alarm, such as methane, hydrogen, propane, etc.
(2) Select the most important gas component in the gas measured by the alarm as the standard gas.
(3) Use alternative gas for verification.
(4) Use the calibration gas given in the alarm manual, with calibration coefficient or correction curve.
(5) The oxygen content in the standard gas should not be too low.
Description:
Explosion-proof combustible gas sensors, stable performance, sensitive and reliable. With high-precision liquid crystal display, explosion-proof housing, diffusion or pump suction. The combustible gas sensor has the characteristics of flexible use and simple operation. Suitable for all kinds of gas leakage places, such as: city gas, petroleum, chemical, pharmaceutical and other fields. The explosion-proof grade of the combustible gas detector is CT6. We are factory direct sales, you can trust.
Features:
(1) High-definition LCD color screen display, industrial-grade high-definition interface, intuitive display with 320*240 resolution;
(2) Multi-machine selection of alarm controller, rich in optional external control ports, easy to use, sound and light alarm;
(3) Waterproof, dustproof, explosion-proof, anti-condensation, the shell adopts die-cast aluminum technology, IP65 waterproof;
(4) 15 seconds quick response, the probe adopts the international high-quality sensor probe.
(5) A variety of signal output, support RS485/4G/Lora and other signal output;
Details:
(1) Quality assurance of high-quality probes. We use a variety of high-quality probes to ensure that the probes are sensitive and have a long life;
(2) Fine workmanship, waterproof and dustproof: double waterproof treatment for shell seam/wire interface, waterproof grade up to IP65;
(3) Die-cast aluminum shell with high explosion-proof grade: the shell is Exd II CT6 explosion-proof to protect the internal components;
(4) Double protection of sound and light alarm. The alarm can produce a siren sound of nearly 80dB(A).
A one-second warning is especially valuable in the 20 minutes it takes for a gas leak to trigger an explosion. At the first time of receiving the danger notice The user can immediately make the necessary hidden trouble removal work. In serious cases, can also call the gas emergency repair telephone or immediately alarm. To prevent serious explosion accidents caused by gas leakage.
In addition to combustible gas sensors, JXCT also introduces smoke, toxic gas and other types of sensors. which can carry out real-time monitoring and second-level warning of smoke concentration, wire temperature, current size and so on.
JXCT gas sensor helps protect the safety of the entire home and its members.
So what occasions, such as industrial operations, iron works. Chemical plants, and even families, can use a combustible gas alarm to prevent in case. After all, human life only once.
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