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Vicat needle

Setting times are commonly defined empirically, using a Vicat needle. In this device, weighted needles of standard design are allowed to sink into the paste, and initial and final set defined as the times when the degree of penetration falls below specified levels. In the British standard, whieh is typical, initial set must occur not earlier than 45 min, and final set not later than 10 h. [Pg.231]

The Vicat needle method consists of determining the temperature at which a 1-mm penetration of a needle (having a point with an area of 1 mm) occurs on a standard sample (0.32 cm thick with a minimum width of 1.8 cm) at a specified heating rate (often 50 °C/h) under specific stress (generally less than 1 kg). This determination is related to the heat deflection point. [Pg.40]

ASTM. Standard test method for time of setting of hydraulic cement by Vicat needle. ASTM standards. 2002 C191-01a 1-6. [Pg.41]

Gilhnore Needle. Apparatus for the determination of the initial and final set of Portland cement (Q. A. Gillmore, Practical Treatise on Limes, Hydraulic Cements and Mortars, New York, 1864). The present form of apparatus consists of two loaded rods which slide vertically in a frame the rod ( needle ) for the determination of initial set is Vn in. (2 mm) dia. and weighs V lb (llOg), the needle for the final set is Via in. (1 mm) dia. and weighs lib (446g). Details are given in ASTM-C2 (cf. vicat needle). [Pg.140]

Vicat Needle. An instrument for evaluating the consistency of cement in terms of the depth of penetration of a needle of standard shape and under a standard load it was designed by L. J. Vicat, a Frenchman, in the early 19th century. Details of dimensions and... [Pg.346]

Vicat needle apparatus conforming to BS complete with accessories furthermore (as spares) ... [Pg.395]

C 191 Test Methods for Time of Setting of Hydraulic Cement by Vicat Needle... [Pg.109]

Method.—For this purpose the Vicat Needle, which has already been described in paragraph 17, should be used. [Pg.123]

Time of Setting by Vicat Needles— Test Method C 191. [Pg.154]

VIcat Vicat Softening Point (VSP). A thermal softening point test performed using a Vicat needle instrument, quoted in °C. It is measured by applying a standard load, either 10 or SON, via a circular indentor onto a specimen. The sample is heated at a constant rate until the indentor sinks into the sample by a set distance. The result is quoted with respect to the load applied and temperature. [Pg.141]

Two particular test methods have become very widely used. They are the Vicat softening point test (VSP test) and the heat deflection temperature under load test (HDT test) (which is also widely known by the earlier name of heat distortion temperature test). In the Vicat test a sample of the plastics material is heated at a specified rate of temperature increase and the temperature is noted at which a needle of specified dimensions indents into the material a specified distance under a specified load. In the most common method (method A) a load of ION is used, the needle indentor has a cross-sectional area of 1 mm, the specified penetration distance is 1 mm and the rate of temperature rise is 50°C per hour. For details see the relevant standards (ISO 306 BS 2782 method 120 ASTM D1525 and DIN 53460). (ISO 306 describes two methods, method A with a load of ION and method B with a load of SON, each with two possible rates of temperature rise, 50°C/h and 120°C/h. This results in ISO values quoted as A50, A120, B50 or B120. Many of the results quoted in this book predate the ISO standard and unless otherwise stated may be assumed to correspond to A50.)... [Pg.188]

The most widely used method is that of Vicat in which a blunt steel needle (area of point 1 mm ) is applied vertically to the surface of a test piece (about 1 cm and 3-4 mm thick) under a load of 49 N. The oven temperature is then raised at 50 °C/h and the temperature determined at which the needle has simk 1 mm into the test piece this is taken as the softening point (Vicat temperature). [Pg.121]

In the Vicat test, the polymer sample is subjected to a load of 1 kg on a standard needle. The sample is immersed in a bath and heated, and the softening point is defined as the temperature at which the loaded needle penetrates to a depth of 1.0 mm. [Pg.35]

With the Vicat test a steel needle, at the end flattened to an area of 1 mm2 is pressed into a block of the material with a standard force (1 kgf for Vicat-A, 5 kgf for Vicat-B). The temperature is increased at a standard rate of 50 °C / hour until the needle has penetrated 1 mm into the sample then the Vicat softening point has been reached. As well as we have seen with the Shore hardness ( 7.5.1), this process of penetration is, in fact, also governed by the E-modulus of the material, though in a much more complicated way. Globally, also to the Vicat test a characteristic E-modulus can be ascribed, which is lower than with the ISO bending test, namely about 200 MPa for Vicat-B and 40 MPa for Vicat-A. [Pg.145]

Another standard heat distortion test is the Vicat test where a flat-ended needle (diameter 1 mm) penetrates to the depth of 1 mm under a specific load of 50 N (Vicat A) or 10 N (Vicat B). It will be clear that the penetration depth is again determined by the Young modulus, although in a much more complicated way than in the bending test. A rough estimate yields Vicat softening temperatures where E 1000 MPa (Vicat A) or E 200 MPa (Vicat B). [Pg.849]

Covers the determination of the temperature at which a specified needle penetration occurs when specimens are subjected to specified test conditions. The method is useful for many thermoplastic materials. The specimen and needle are heated at either of two permissable rates. The temperature at which the needle has penetrated to a depth of 1 mm is the Vicat softening temperature. [Pg.409]

ASTM D1525 provides a third type of the softening temperature test. A hat-ended needle of 1 mm circular cross-section is pressed into a thick sheet of the polymer with a load of 1.0 kg. The polymer is heated at a rate of either 50 or 120 K/h. The Vicat softening temperature is the temperature at which the needle has penetrated the polymer to a depth of 1 mm. For such a depth of penetration, the material must be very soft, hence the Vicat softening temperature is higher than other HDT data. [Pg.914]

Two particular test methods have become very widely used. These are the Vicat softening point test and the test widely known as the heat distortion temperature test (also called the deflection temperature under load test). In the Vicat softening point test a sample of polymer is heated at a specified rate temperature increase and the temperature is noted at which a needle of specified dimensions indents into the polymer a specified distance under a specified load. [Pg.365]

The Vicat temperature measures the penetration of a needle into a sample under otherwise constant conditions. Thus, the method also measures elasticity and surface hardness. [Pg.385]

The tests were conducted by help of a programmable automatic Vicat device allowing temperature control of the surrounding water storage and continuous logging of the penetration depth. This enables to observe the full penetration curve between initial and final set. Since the times between initial and final set were comparable for all mixes at each particular temperature, the time at which a needle penetration depth of 20 mm was reached was chosen to represent a median between initial and final setting times. [Pg.100]

The Vicat softening temperature is the temperature at which a flat-ended needle penetrates the specimen to a depth of 1 mm under a specific load. [Pg.26]

A test specimen is plaeed in the testing apparatus such as that diagrammed in Figure 1.32. The penetrating needle rests on its surface. A load of 10 or 50 N is applied to the specimen. The speeimen is then lowered into an oil bath at 23°C. The bath is raised at a rate of 50°C/h or 120°C/h until the needle penetrates 1 mm. The temperature at that moment is called the Vicat softening temperature. [Pg.26]

Vicat softening point n. The temperature at which a flat-nosed needle of 1-mm circular cross section penetrates a thermoplastic specimen to a depth of 1 mm under a specified load using a uniform rate of temperature rise (www.astm.org). This test is used... [Pg.1041]

Vicat softening point— ASTM D1525. The Vicat softening point is not provided on this particular data sheet, however, it is a method of determining the softening point of plastics which have no definite melting point. A 1000-g load is placed on a needle with a 0.0015-in circular or square cross section. The softening point is taken as the point where the needle penetrates the specimen to a depth of 1 mm. [Pg.628]


See other pages where Vicat needle is mentioned: [Pg.494]    [Pg.71]    [Pg.394]    [Pg.86]    [Pg.122]    [Pg.208]    [Pg.280]    [Pg.494]    [Pg.71]    [Pg.394]    [Pg.86]    [Pg.122]    [Pg.208]    [Pg.280]    [Pg.152]    [Pg.152]    [Pg.80]    [Pg.116]    [Pg.322]    [Pg.202]    [Pg.60]    [Pg.366]    [Pg.539]    [Pg.214]    [Pg.385]    [Pg.34]    [Pg.385]    [Pg.1112]   
See also in sourсe #XX -- [ Pg.155 ]




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