BAIRD &TATLOCK (LONDON) LTD." 



5004 



5004 5 Pensky-Marten's Flash Point Apparatus, with stirrer, and thermometer 80 to 250 C., 

 complete with burner, packed in pine case 



If different range of thermometer is required, particulars must be given 



with order. 



DESCRIPTION. 



This apparatus, which is designed for the testing of heavy oils, consists of an oil cup with cover fitted with 

 thermometer and stirrer, and an air bath. The bath may be heated by a gas flame or spirit lamp, and the slow 

 and regular heating of the oil is ensured by the jacket of air that surrounds the cup. 



The determination of the flashing point is effected by rotating the vertical spindle by means of the milled head 

 whereby the sliding cover is opened, and simultaneously a small flame burning at the movable jet is brought 

 to the opening. This is repeated at intervals during the rise of temperature until a flash occurs in the space above 

 the oil, and the temperature at which this occurs is the flashing point. 



INSTRUCTIONS FOR USE. 



The cup is filled to the ring inside with the oil to be tested, and the cover placed in position so that the test- 

 jet is not above either of the two hooks on the collar of the cup. The cup is then placed in the bath by means 

 >f the fork provided for that purpose, which ensures steadiness of movement, and prevents the walls of the cup 

 from becoming oily above the proper level. The thermometer having been inserted in the socket in the cover, 

 the gas burner is lighted beneath the wire gauze screen, and the rate of heating so adjusted that the temperature 

 af the oil under examination rises 10 F. in each minute. The gas test-jet is then lighted, and is regulated by means 

 :>f the screw valve until the flame is of the size of a small pea. During the heating of the oil the stirrer is used 

 from time to time. At each rise of one degree of the thermometer, the test flame is applied by rotating the spindle 

 until the flashing point is reached, the use of the stirrer being intermitted while this is done. If the flashing point 

 3f the oil is known approximately, the rate of heating may at first be accelerated by using a larger flame and by 

 removing the wire gauze, but the rate must be adjusted to 10 F. per minute at least 20 degrees below the flashing 

 point. 



As traces of the more volatile hydrocarbons considerably reduce the flashing point, it is essential that the 

 apparatus during use should be kept free from such. It is also necessary to keep the oil cup perfectly dry, as 

 traces of moisture interfere with the production of the flash. Care must therefore be taken that the oil is free 

 from water before testing. 



If the heating agent is gas the test flame is also gas, but where gas is not available the test flame is fed with 

 rape or mineral oil. The oil flame is regulated by adjusting the wick, the gas-jet by a regulating screw. 



Further particulars of this apparatus are given in the second part, 1889, of the reports of the Konigl. tec/in. 

 Versuchanstalten, Berlin, pp. 64-74. 



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CHEMICAL AND SCIENTIFIC APPARATUS AND PURE CHEMICALS. 



909 



