Flow cups

There is no entirely satisfactory way of measuring flow. In the BS 2782 flow cup test an amount of moulding powder is added to the mould to provide between 2 and 2.5 g of flash. The press is closed at a fixed initial rate and at a fixed temperature and pressure. The time between the onset of recorded pressure and the cessation of flash (i.e. the time at which the mould has closed) is noted. This time is thus the time required to move a given mass of material a fixed distance and is thus a measure of viscosity. It is not a measure of the time available for flow. This property, or rather the more important length of flow or extent of flow, must be measured by some other device such as the flow disc or by the Rossi-Peakes flow test, neither of which are entirely satisfactory. Cup flow times are normally of the order of 10-25 seconds if measured by the BS specification. Moulding powders are frequently classified as being of stiff flow if the cup flow time exceeds 20 seconds, medium flow for times of 13-19 seconds and soft flow or free flow if under 12 seconds. 

Cup flow BS2782-86 Method 720 B Slow-curing thermosets Measure time to fill Set closing speed, force, amount of flash and temperature... 

BS 2782. Part 7, Method 720B, Cup flow of phenolic and alkyd molding materials 1979. ASTM D731-95. Molding Index of thermosetting molding powder. 

DIN 53465. Determination of the closing time of thermosetting molding materials, cup flow test method. 

Cup-flow test n. A British standard test (B S 771) for measuring the flow properties of phenolic resins. A standard mold is charged with the specimen material and then closed under preset pressure. The time in seconds for the mold to close completely is the cup-flow index. 

Capillary rheometer Capillary viscometer Consistency Cup-flow test... 

Cup flow test Test for measuring the flow properties of thermosetting materials. A standard mold is charged with preweighed material, and the mold is closed using sufficient pressure to form a required cup. Minimum pressures required to mold a standard cup and the time required to close the mold fully are determined. 

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