Open cup test

Tag open-cup test Taguchi designs Taguchi gas sensors Taiguie acid Tailings... 

From the point of view of the potential for a fire, the closed cup flash point determination is usually the most important. In a perfect closed cup test, the vapor pressure is in equilibrium with the liquid at the temperature of the test. At the flash point, the vapor composition is at the lower flammable limit. In fact, the lower flammable limit can be estimated from vapor pressure data (for a pure compound). Open cup flash points are generally higher and, thus less conservative, than closed cup determinations. The value determined in an open cup test is subject to air movement at the open face of the cup and true vapor-liquid equilibrium probably does not occur. 

Liquid, or mixtures of liquids, or liquids containing solids in solution or suspension which give off a flammable vapor at temperatures of not more than 60.5°C, closed-cup test, or not more than 65.6°C, open-cup test. 

If data are not available, the flash point and the initial boiling point shall be determined through testing. The flash point shall be determined by closed-cup test method. Open-cup tests are acceptable only in special cases. 

Flammable liquids are liquids, or mixtures of liquids, or liquids containing solids in solution or suspension (for example paints, varnishes, lacquers, etc., but not including substances otherwise classified on account of their dangerous characteristics) which give off a flammable vapour at temperatures of not more than 60.5°C, closed-cup test, or not more than 65.6°C, open-cup test, normally referred to as the flash point. [Text continues.] UN 2.3.1.1... 

As per OSHA recommendations. Use of Cleveland Open Cup Test yields values significantly higher. 

Performance can be illustrated for example by the time necessary for deaeration or de-emulsification of oils, anti-rust properties, copper strip corrosion test, the flash point in closed or open cup, the cloud and pour points, the foaming characteristics, etc. 

Flash Point (ASTMD92). The Cleveland open cup method is most commonly used although the Tag open cup (ASTM D3143) is apphcable to cutbacks. Flash point is an indication of fire hazard and the test is frequendy used to indicate whether a given product has been contaminated with materials of lower dash point. 

The flash point is the lowest temperature at which a liquid gives off sufficient vapor to form an ignitable mixture with air near the surface of the liquid or within the vessel used. ASTM test methods include procedures using a closed cup (ASTM D56, ASTM DOS, and ASTM D3828), which is preferred, and an open cup (ASTM D92 and ASTM D1310). When several values are available, the lowest temperature is usually taken in order to assure safe operation of the process. 

Flashpoint — the lowest temperature of a liquid at whieh it gives off enough vapor to form an ignitable mixture with air near the surfaee of the liquid within the vessel used. Two tests are used—Open Cup and Closed Cup. Generally, the Open Cup method results in flashpoints 5° to 10° higher than the Closed Cup method. Flashpoint < 140°F (Closed Cup) is the eriterion used by EPA to deeide whether a ehemieal is hazardous by ignitability. DOT defines materials with flashpoints of < 100°F as flammable materials, and between 100° and 200°F as eombustible. 

Flash Point - The flash point of a material is the lowest temperature at which vapors above a volatile substance will ignite in air when exposed to a flame. Depending on the test method used, the value of flash point temperature is either Tag Closed Cup (CC) based on ASTM D56 test method, or Cleveland Open Cup (CC) based on ASTM 093. The value provides a relative indication of the flammability of the chemical. 

Flash point temperatures are determined using an open-cup apparatus, shown in Figure 6-3. The liquid to be tested is placed in the open cup. The liquid temperature is measured with a thermometer while a Bunsen burner is used to heat the liquid. A small flame is established on the end of a movable wand. During heating, the wand is slowly moved back and forth over the open liquid pool. Eventually a temperature is reached at which the liquid is volatile enough to produce a flammable vapor, and a momentary flashing flame occurs. The temperature at which this first occurs is called the flash point temperature. Note that at the flash point temperature only a momentary flame occurs a higher temperature, called the fire point temperature, is required to produce a continuous flame. 

Figure 6-3 Cleveland open-cup flash point determination. The test flame applicator is moved back and forth horizontally over the liquid sample.

The liquid temperature (Tl) corresponding to Xl is measured for practical purposes in two apparatuses known as either the closed or open cup flashpoint test, e.g. ASTM D56 and D1310. These are illustrated in Figure 6.3. The surface concentration (Xs) will be shown to be a unique function of temperature for a pure liquid fuel. This temperature is known as the saturation temperature, denoting the state of thermodynamic equilibrium... 

Figure 6.3 Fuel concentration differences in the closed and open cup flashpoint tests...

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 but recent research has yielded higher and lower flash points dependent on the surface area of the ignition source. Because of this aspect ASTM and other standard test methods have been recently withdrawn. They are under review until an adequate determination of a practical and comprehensive standard is composed and agreed upon. 

Of the available test methods, the most common method of determining the flash point confines the vapor (in a closed cup) until the instant the flame is applied (ASTM D56, D93, D3828, D6450 IP 34, IP 94, IP 303). An alternative method that does not confine the vapor (open cup method ASTM D92, D1310 IP 36) gives slightly higher values of the flash point. 

Flash point The flash point is defined as the minimum temperature at which a substance releases ignitable flammable vapors in the presence of an ignition somce, e.g., spark or flame. Flash points may be determined by two methods Tag closed cup via American Society for Testing and Materials (ASTM) method D56 or Cleveland open cup via ASTM method D93. Unless otherwise noted, all... 

Standardized test using a small quantity of liquid that is slowly heated until a flash is observed when an open flame is dipped down into a covered vapor space. Flash point temperatures are normally given as open cup or closed cup, based on the type of apparatus used to measure the flash point. The open cup flash point is normally a few degrees above the closed cup flash point. 

Flash Point (flash p). This is the lowest temperature at which a liquid will give off enough flammable vapor at or near its surface such that in intimate mixture with air and a spark or flame it ignites. The flash point of liquids is usually determined by the Standard Method of Test for Flash Point with the Tag Closed Cup Tester (ASTM D56-52, available from the American Society for Testing Materials, 1916 Race St, Philadelphia, Pa). This method is also the standard of the American Standards Association (ASA Z 11.24-1952, available from the American Standards Association, 70 East 45th St, New York, NY). The Interstate Commerce Commission uses the Tag Open Cup (TOC) Tester giving results 5—10°F higher (less flammable). Other methods frequently used are... 

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). 

A. FLASH AND FIRE POINTS BY CLEVELAND OPEN CUP METHOD (COC). The Cleveland Open Cup Apparatus is described as Method 4294 (Sept 1965) of Federal Test Method Standard No 141a... 

The Cleveland Open Cup is filled to a specified level with sample. The temp is increased rapidly at first and then at a slow constant rate as the flash point is approached. At specified intervals a small test flame is passed across the cup. he lowest temp at which the flame causes vapors above the liq to ignite is taken as the flash point [For details see ASTM Standards, Part II (1971), pp66—92]... 

Flash point tests 1 XVI—XVII 6 F80—F96 flash and Are points by Cleveland open cup method 6 F80—F82 flashpoint 6 F80... 

Cleveland Open Cup (COC). An apparatus used for testing flash and fire points of flammable liquids... 

COC. Abbr for Cleveland Open Cup, a type of flash point test... 

Cleveland Open Cup (COC)-test (ASTM D 92) for determining the flash point and fire point of all petroleum products except fuel oil and products with flash points below 79oC (175oF). The oil sample is heated in a precisely specified brass cup containing a thermometer, specified intervals a small flame is passed across the cup. The lowest temperature at which the vapors above the cup briefly ignite is the flash point the temperature at which the vapors sustain combustion for at least five seconds is the fire point. See Tag open cup. 

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