Pensky -Marten flash point apparatus

Pensky-Martens dosed tester-apparatus used in determining the flash point of fuel oils and cutback asphalt, under conditions prescribed by test method ASTM D 93. The test sample is slowly heated in a closed cup, at a specified constant rate, with continual stirring. A small flame is introduced into the cup at specified... 

Figure 4.5. Pensky-Marten s flash point apparatus (ASTM D-56)...

Flowever, for cut-backs and fluxed bituminous binders, the flash point is usually determined by the Pensky-Martens closed-cup apparatus (ISO 2719 2002 or ASTM D 93 2013), by the tag open-cup apparatus (AASHTO T 79 2012 ASTM D 3143 2008) or by the Abel closed-cup apparatus (CEN EN ISO 13736 2013). 

PM Pensky-Martens (apparatus measuring flash point)... 

Al.l The low-range thermometer, which conforms also to the specifications of the cup thermometer in the Tag Closed Tester (ASTM Method D 56, Test for Flash Point by Tag Closed Tester) and which frequently is fitted with a metal ferrule intended to fit the a>llar on the lid of the Tag Flash Tester, Can be supplemented by an adapter (Fig Al) to be used in (he larger diam collar of the Pensky-Martens apparatus. Differences in dimensions of these collars, which do not affect test results, are a source of unnecessary trouble to manufacturers and suppliers of instruments, as well as to users... 

ASTM D 3278-96, Standard test methods for flash point of liquids by setaflash closed-cup apparatus ASTM D 0093-96, Standard test methods for flash point by Pensky-Martens closed cup tester... 

The Pensky-Marten apparatus using a closed or open system (ASTM D-93, IP 34, IP 35) is the standard instrument for flash points above 50°C (122°F), and the Abel apparatus (IP 170) is used for more volatile oils, with flash points below 50°C (122°F). The Cleveland open-cup method (ASTM D- 92, IP 36) is also used for the determination of the fire point (the temperature at which the sample will ignite and bum for at least 5 s). 

The Abel closed-cup apparatus (IP 170) consists of a brass cup sealed in a small water bath that is immersed in a second water bath. The cover of the brass cup is fitted in a manner similar to that in the Pensky-Marten apparatus. For crude oils and products with flash point higher than 30°C (>86°F), the outer bath is filled with water at (131°F) and is not heated further. The oil under test is then placed inside the cup. When the temperature reaches 19°C (66°F) the pilot flame is introduced every 0.5°C (l.O F) until a flash is obtained. For oils with flash points in excess of 30°C (>86 F) and less than 50°C (<122°F), the inner water bath is filled with cold water to a depth of 35 mm. The outer bath is filled with cold water and heated at a rate of l°C/min (1.8°F/min). The flash point is obtained as before. 

A variety of apparatus such as the small scale closed tester, flic tag open cup, the tag closed tester,the Cleveland open cup, the Pensky-Martens closed cup, and the equilibrium method are used to determine the flash point. The selection of method is based suggestions included in separate standard. ... 

The Cleveland open cup is placed on a heated plate which increases temperature at a rate of 5-6 C/min. This method can also be automated. The method is designed for testing petroleum products which are viscous and have flash point above 79"C. The Pensky-Martens closed cup tester was also designed for petroleum products but for those with flash points from 40 to 360 C. This apparatus has its own heating source, stirrer, and cover by which it differs from Cleveland cup. It can be either manual or automated. The equihbrium method uses eiflier a modified tag close cup or the Pensky-Martens apparatus. The modification intended to keep flic vapor/air temperature in equilibrium with the liquid temperature. The method is limited to the temperature range from 0 to 110 C. 

The flash and fire points of petroleum products such as bitumens and bituminous binders, having an open cup flash point above 79 C, are determined by the Cleveland open cup apparatus. For fuel oils, the most common test method used is the closed cup procedure that uses the Pensky-Martens apparatus (see ISO 2719 2002 or ASTM D 93 2013). 

When the Pensky-Martens apparatus is used, the expected flash point of cut-backs and fluxed bituminous binders should be >60°C when the tag open-cup apparatus is used, the expected flash point may vary from >38°C to >66°C and when the Abel closed-cup apparatus is used, the flash point may vary from 23°C or less to >45°C. 

The lowest temperature of a flammable liquid at which it gives off sufficient vapor to form an ignitable mixture with the air near the surface of the liquid or within the vessel used. The flash point has been commonly determined by the open cup or closed cup method (ASTM D 56, Standard Test Method for Flash Point by Tag Closed Cup Tester, ASTM D 92, Standard Test Method for Flash and Fire Points by Cleveland Open Cup Tester, ASTM D 93, Standard Test Method for Flash Point by Pensky-Martens Closed Cup Tester ASTM D 3278, Standard Test Method for Flash Point of Liquids by Small Scale Closed Cup Apparatus, ASTM D 3828, Standard Test Method for Flash Point by Small Scale Closed Cup Tester), but recent research has yielded higher and lower flash points depending on the surface are of the ignition source. 

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