Скачать или смотреть How an Lpg Cut-off Device works - A comprehensive Demo.

Gas when it is inside a LPG cylinder is in zone 0 state or also in liquid state the levels of gas inside is above Upper Explosive Limits ( UEL) of LPG, when it starts leaking it dilutes and comes in the explosive band between ( LEL & UEL ) this mixture is very flammable and if it is in range of 1.9% - 9.5% Vol then it is susceptible to catch fire or cause an explosion.
Please understand that LPG expands almost 270 times when it changes from liquid to gas state ie 1 liter of liquid LPG equals 270 liters of gasesous LPG.LPG when filled in cylinder in liquid form it is at - 44degC, when pressure is 0 PSIG, when temperature of cylinder becomes 27 DegC the pressure is around 128 psig, when temperature of cylinder crosses 50 degC it is almost 260 psig so a LPG cylinder is virtually becoming a pressurised bomb as temperatures of cylinders goes up,so when there is a fire try and remove the cylinders outside as it can blast in fire temperature which can go as high as 500-2000 degC.

We often hear of explosions and fire accidents in homes in India involving domestic LPG cylinders.They have earned a bad name since the explosions and fires are attributed to these. Lot of inquiry committees have been investigating these explosions but we are not aware if any solution has been recommended. These explosions are many times devastating, collapsing the roof of the building and killing many people. When LPG cylinders are NOT involved, home fires are seldom so catastrophic since Indian homes are made of masonry and RCC. Now most urban homes have LPG cylinders in the kitchens. Some spare filled LPG cylinders may also be kept indoors.

We are aware of Improvised Explosive Devices (IEDs) used by terrorists. In the west, one of the common IEDs are propane cylinders, which are readily and cheaply available for barbecue.These are steel cylinders filled with 5 –10 kg liquid propane under a pressure of approx. 10 bar. The critical temperature for propane is 96.6 deg C, meaning that above this temperature, it cannot be liquefied even at greatest pressure.When a fire breaks out for any reason in the kitchen or any other indoor space where this cylinder is kept, the 14 kg liquid propane filled in such a cylinder may be heated to 400 deg C. Its pressure increases on two accounts.Firstly, all 14 kg liquid will be converted into gas phase to occupy approx. 28 lit fixed volume of the 14 kg LPG cylinder. Secondly, the pressure will also increase due to the increase of temperature as per gas laws.These two factors suddenly cause a large increase the internal gas pressure. ’Back of the envelope’ type calculations indicate that the propane may reach pressures above 400 bar under this example.These pressures are much higher than the design and test bursting pressure of these cylinders, which is only approx. 90 bar. (If the quantity of propane was less than 14 kg, the increase of pressure will be lesser.) Unlike the larger LPG cylinders, the small domestic LPG cylinders in India are not provided with any excess pressure relief valve or rupture disc.A propane cylinder therefore works as an IED as it explodes violently when a fire in the vicinity heats it.The suddenly added large quantity of propane gas adds a lot of highly inflammable fuel to the ongoing fire, causing more explosions (including BLEVE – Boiling Liquid Expanding Vapor Explosion) & catastrophic damage.

LPG used in India is a mixture of Butane and Propane in the ratio of approx. 3:1.Butane is a gas next to propane in the same series and has little lower saturated vapor pressures at same temperatures than propane. This means that we are keeping more than approx.100 million IEDs in our kitchens and homes in India. Whenever a fire occurs where even one such LPG cylinder is kept, an explosion is likely to follow. The fire may be an accident caused by a number of factors. But the explosion that follows is not any accident. It is inevitable with an IED kept indoors, waiting to explode when a fire occurred.

One GAS SHUT OFF device named "GAS FUSE" invented in Australia since 1988 and introduced in Indian Market since 1998 and in 1998 Deptt,of Explosives, now,PESO has given NOC to that device after verifying its performance.This device is available in India by the name of GAS SAFETY DEVICE,for a cost of Rs.2590/- which immediately cuts the gas supply incase of major leaks in the pipeline, and Regulator failure or valve rupture etc.This device when installed between the cylinder and the Lpg regulator, cuts off the supply in the event of abnormal flow of LPG as when the hose is ruptured, or a child tugs off the hose or there is a joint breakage at the point of entry to the cooktop. The device's cost is not a big amount to invest comparison to the cost of our family members' life . #gassafe #flamefailuredevice #gasleak #lpgleakage #lpgaccident #lpgemergency #lpgcanbemerciless #preventlpgaccidents
Follow us on Instagram- https://bit.ly/2vhfDZT
🇮🇳🇮🇳🇮🇳🇮🇳🇮🇳🇮🇳🇮🇳🇮🇳🇮🇳🇮🇳🇮🇳🇮🇳