Three Common Problems of Combustible Gas Detectors
A combustible gas detector system consists of a detector and an alarm. It is widely used in many industries prone to severe gas leakage, such as petroleum industry, household gas pipelines, chemical plants and oil depots. It monitors gas leakage in hazardous indoor and outdoor areas and serves as vital equipment to guarantee operational and personal safety. When combustible gas leaks on site, the instrument displays the concentration as a percentage of the Lower Explosive Limit (LEL). Explosion risks will rise once the gas concentration exceeds this limit. Therefore, the following points shall be noted during application. Once installed, combustible gas detectors are difficult to relocate, so the mounting position must be carefully determined in advance.
① Identify all potential leakage points on monitored equipment, analyze and mark possible leakage directions before installation. As different combustible gases have varying densities, a three-dimensional gas flow diagram shall be created based on air movement, with initial monitoring points arranged at downstream positions.
② Analyze the leakage mode: slow micro-leakage or jet-type heavy discharge. For slight micro-leakage, the combustible gas detector shall be installed close to the leakage point; for jet-type large leakage, the detector shall be placed further away to obtain accurate concentration readings. After completing the above procedures, the required quantity of detectors can be calculated. For sites with high risks of massive combustible gas leakage, one detection point shall be arranged every 10–20 meters in accordance with relevant regulations. For unattended small pump houses operating intermittently, potential gas leakage risks shall be considered, and one detector is generally installed at the downwind side.
③ Many accident investigations reveal that improper installation positions of combustible gas detectors lead to delayed leakage detection. Without timely emergency response, serious accidents may consequently occur.
