Martens test

Other tests occasionally quoted are the BS softening point test and the Martens test. These involve the bending under load of samples held at one end as they are subjected to a rise in temperature. 

Methods of test for petroleum and its products. Determination of flash point. Pensky-Martens closed cup method. 

As for all petroleum products, considerations of safety in storage and transportation and, more particularly, contamination by more volatile products are required. This is usually accommodated by the Pensky-Martens flash point test (ASTM D93 IP 34). For the fuel oil, a minimum flash point of 55°C (131°F) or 66°C (150°F) is included in most specifications. 

In the method of Martens a test rod is mounted upright in a support and the upper free end is put under a bending stress via a small weighted lever. The rod is slowly heated in an oven until a specified deflection is attained. The softening point determined in this way is called the Martens temperature. 

When the number of noisy (noninformative) variables is too large, PLS models may also supply rather poor predictive performance. In order to overcome such a matter, a number of techniques for the elimination of noisy variables or the selection of useful predictors have been deployed, such as iterative stepwise elimination (ISE), iterative predictor weighting (IPW), uninformative variable elimination (UVE), and Martens uncertainty test (MUT) (Forina et ah, 2007). 

Cleveland Open Cup (COC) and Pensky-Martens (PM). The closed cup flash point value is usually several degrees lower (more flammable) than the open cup, as the test in the former case is made on a saturated vapor-air mixture, whereas in the latter case the vapor has free access to air and thus is slightly less concentrated. For this reason, open cup values more nearly simulate actual conditions (see below). 

This specification defines the Pensky-Martens Closed Flash Tester as used in ASTM Method D93, Test for Flash Point by Pensky-Marcens Closed Tester... 

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 collar on the lid of the Tag Flash Tester, can be supplemented by an adapter (Fig Al) to be used in the larger diam collar of the Fen sky-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... 

A1.2 Subcommittee 21 on Metalware Laboratory Apparatus, of Committee E-l on Methods of Testing, has studied this problem and has established some dimensional requirements which are shown in Fig Al. Conformity to these requirements is not mandatory, but is desirable to users as well as suppliers of Pensky-Martens Testers... 

A good applications-oriented measure of the use temperature for a ma-teral is the heat distortion or heat deflection test (HDT). The HDT is described by ASTM-D648 as the temperature at which a sample of defined dimensions (5 X Vi X Vs (or Va) in.) deflects under a flexural load of 66 or 264 psi placed at its center. In case of a largely amorphous polymer, the HDT temperature is typically slightly (10 to 20 °C) lower than the Tg as determined by DSC or DTA, whereas with more-crystalline polymers, it more closely correlates with the Tm. The HDT temperature is a useful indicator of the temperature limits for structural (load-supporting) applications. A loaded cantilever beam is used in another heat deflection test called the Martens method. 

Martens followed the first course, but it is far much common to give the results by determining the scratch width at a constant load. This is because of the greater simplicity of measurement and the possibility of using standard instruments. Also a change in scratch width in tests under constant load reflects a change in hardness of the sample under test. 

Because the oxidation of phenol is sensitive to the purity of the titanium silicate catalyst, it has been used as a test reaction to evaluate the purity of the catalytic materials. A standard material called EURO TS-1 has recently been prepared and evaluated in several laboratories (Martens et al., 1993). 

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... 

BSI 1998b. Methods of Analysis of Fats and Fatty Oils, Part 1. Physical Methods, Section 1.17. Flashpoint limit test using Pensky-Martens closed-cup flash tester, British Standards Institution, London. 

Flash Point-Pensky-Martens Closed Cup for Fats and Oils (Cc 9b-55) determines the temperature at which an oil sample will flash when a test flame is applied. This technique sometimes is used to estimate levels of residual hexane and to ensure the safety of workers handling the oil. Some refineries use gas chromatography methods instead. 

Cleveland Open Cup (COC) and Pensky-Martens (PM). The dosed cup flash point value is usually several degrees lower (more flammable) than the open cup, as the test in the former case is made on a saturated vapor-air mixture, whereas in the latter case the vapor has free access to air and thus is slightly less concentrated, For tliis reason, open cup values more nearly simulate actual conditions (see below), Fire Point (fire pt). Tliis is the lowest temperature at which a mixture of air and vapor continue to burn in an open container when ignited. It is usually above the flash point. Where the flash point is available, only it is given if it is not, the fire point may be given. It is at least as significant as the flash point as an indication of the fire hazard of... 

Martens s ndbook on Testing Materials. (Henning.) a vols.8vo, 7 So... 

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... 

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