Flash and fire points, Chemical Engineering

Assignment Help:

Q. Define flash and fire points and its determination.

                                OR

Write short note on: Flash and fire points.

Ans. Flash and fire points: Flash point of oil is the lowest temperature at which the combustible liquid gives off sufficient vapours that spontaneously ignite for a moment when a small flame is brought near the vapour of lubricating oil. Fire point of oil is also the lowest temperature at which the vapours of oil began to produce a continuous flame. A liquid having flash point less than 140 degree centigrade is called a flammable liquid. Fire point of oil is 5 to 40 degree centigrade higher than its flash points. Flash and fire points do not have any bearing with the lubricating property of oil, but these are important when oil is exposed to high temperature services.

Following three standardized forms are available for finding out flash and fire points:

Abel flash point apparatus: It is used for the oil flash point below 120 degree centigrade.

Pesky-Marten's apparatus: It is used for the oils which possess flash point above 120 degree centigrade.

Cleveland's open cup apparatus: It is generally used for determination of flash point of fuel oils and other oils having flash point below 175 degree centigrade.

Pesky Marten's apparatus to determine flash and fire points of oil cup:

1.      The oil cup consists of brass and is of a standard size having a mark up to, which the oil has to be filled.

2.      The lid of the oil cups has four openings, which are meant for a special type of stirrer, thermometer, an air inlet and a device for introducing standard flame. The shutter provided at the top of the cup has a lever mechanism.

3.       The assembly is heated in a controlled manner by keeping it on an electric heater.

Working: Oil cup and other parts of the apparatus are cleaned thoroughly. Test oil is filled in the cup of the level of mark. The lid of the oil cup is covered and a thermometer, a stirrer device and a flame exposure are carefully inserted in its opening. Apparatus is heated homogenously when the temperature rises within the range of expected flash point at every 1 degree centigrade rise a flame is introduced for a moment with the help of a shutter. Flash point is recorded at the temperature when a flash appear in the form of a weaker sound and light. The producer is continued as before until the oil vapour catches fire, which stays up to a minimum for five seconds. This is fire point of oil.


Related Discussions:- Flash and fire points

Introduction to aspects of electrical maintenance, INTRODUCTION : Earlier ...

INTRODUCTION : Earlier in this course you have read about the requirements of laboratories. You also know that these requirements can be for consumable and non consumable nature

Mixing salt solutions, Mixing Salt Solutions You mix 195.0 gallons of ...

Mixing Salt Solutions You mix 195.0 gallons of a mixture containing 12.00 wt% NaCl (sodium chloride) and 88.00 wt% water (solution density = 1.0837 g/cm 3 ) with a V 2 -gallon

Water Treatment, Among phosphate and calgon methods, which one would be the...

Among phosphate and calgon methods, which one would be the best option for internal conditioning

Flash point, Flash point: Flash point is lowest temperature at which the l...

Flash point: Flash point is lowest temperature at which the lubricant oil gives off enough vapours that is ignited for a moment. Significance: 1.      Flash point and fir

Strength of materials, A double riveted double cover butt joint is used for...

A double riveted double cover butt joint is used for connecting plates 1.2 cm thick. The diameter of the rivets is 2.2 cm. The permissible stresses in tension - 100 N/mm2 The per

Transparent polymeric materials for eyeglass lenses, a) List various advant...

a) List various advantages and drawbacks of using transparent polymeric materials for eyeglass lenses.  (b) Cite 4 properties (in addition to being transparent) that are important

Chemical engineering thermodynamics 1, I want some lecture notes on propert...

I want some lecture notes on properties of pure substances, Ideal gas laws

Edta, edta softeninig numerical problems

edta softeninig numerical problems

Objectives and requirements of laboratory staff, Objectives : After doing...

Objectives : After doing this exercise based on two different labs of Zoology/Botany/Chemistry Physics, you should be able to: 1. State the check in and check out procedure of

Property of a material by which it can be drawn into wire, The property of ...

The property of a material by which it can be drawn into wires is called as  Ductility is the only property of a material by which it can be drawn into wires.

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd