Universal testing machines

Texture measurements Texture of canned carrots was measured using Instron Universal Testing Machine (Model 1011) fitted with Kramer shear cell. Thirty grams of drained carrot cubes were evenly placed in the Kramer shear cell and were compressed, sheared and extruded using a crosshead speed of 100 mm/min. Each measurement was repeated 10 times and the mean was used to express the firmness of carrot cubes in Newton(N). 

S Vemuri. Measurement of soft elastic gelatin capsule firmness with a universal testing machine. Drug Dev Ind Pharm 10 409 424, 1984. 

Figure 8,10 illustrates the general configuration for testing a film s puncture resistance. We can perform this test in a number of ways. The probe may be attached to the crosshead of a universal testing machine, similar to the one illustrated in Fig. 8.3. We drive the probe down through the film at a constant speed, while recording the force. Alternatively, we can perform an impact puncture test, in a similar fashion to impact plaque testing.

The mechanical strength of the composite disk specimens was tested, before and after immersion, under biaxial flexure conditionsn [8-10] with a universal testing machine (United Calibration Corp., Huntington Beach, CA). The biaxial flexure strength (BES) of the specimens was calculated according to mathematical expression (1) [8-10] ... 

Compression Test. Compression tests similar to that described in (5) were conducted for yield stress C and modulus E measurement. Rectangular neat resin specimens (1.27 cm x 1.27 cm x 2.54 cm) cut from the cast resin plates were tested under compression, as shown in Figure 1, in an universal testing machine at a loading rate of 0.05 cm/min. For each resin system studied, tests were conducted at several temperature levels between -60 and 60 degree C. All specimens were instrumented with strain gages for... 

Texture has a number of component attributes, and some of them can be assessed by mechanical means. The texture or firmness of cooked potatoes is evaluated by subjecting each sample to a compression test using a universal testing machine equipped with a load cell. Cooked potato cylinders are compressed in a single-cycle compression-decompression test. Uniaxial compression is measured with an Instron machine with a lOON load cell. Measurements are performed on hot potato cylinders (depth 12 mm, height 10 mm) from 15 potatoes immediately after cooking, at a deformation rate of 20 mm/min. Stress and strain at fracture are calculated by the Instron series IX version 7.40 software and means of 15 repetitions are calculated. 

Tablets were prepared from both the microcapsules and mixtures using a Dartec Ltd universal testing machine. The quantity of drug contained was a nominal 200 mg and the punch diameter was 10 mm. Compression was at a constant rate of 1 kN s 1 with tablets prepared at 2, 5 and 10 kN. The tensile strength of the tablets was calculated using the formula T=2P/Dtn. The characteristics of the tablets prepared are shown in Table 1.

The mechanical properties (compression strength and % compression) are determined by Instron Universal Testing Machine using a pellet of 20mm x 20mm pressed at a pressure of 1000kgcnf2 similar to the method used for plastics [68]. 

Measured with 50 mm min 1 strain rate in Universal Testing Machine Zwick 1445 (Zwick, Ulm,... 

Figure 2. Tensile strength measurement with the Instron Universal Testing machine...

Experiments were conducted to test some features of spring vs. summer wood and the relative growth rate of stave wood. Sections of barrel staves of American and French origin were tested in an Instron universal testing machine for the force necessary to cause the wood to yield under pressure of a blunt point 0.5 mm in diameter. The force necessary in the summer wood in the same radial direction as fluid would... 

Set an Instron Universal Testing Machine to compress the specimen twice, compressing each time to 50% of its original height. 

The instrumental TPA was developed by a group at the General Foods Corporation Technical Center (Szczesniak and Kleyn, 1963). The parameters obtained from the resulting forcetime curve correlate well with sensory evaluations of the same parameters (Friedman et al., 1963). Later, the Instron Universal Testing Machine was adapted to perform a modified TPA (Bourne, 1968, 1974). A typical Instron TPA curve is shown in Figure H2.3.1. 

Figure H2.3.1 A generalized texture profile analysis curve from the Instron Universal Testing Machine. A1, area 1 A2, area 2 A3, area 3. The dotted lines indicate the times at which hardness is measured. See text for further discussion. Reprinted from Pons and Fiszman (1996) with permission from Food and Nutrition Press.

To determine the wet bond strength coated panels were immersed in distilled water for 1500 h, removed and discs 25.4 mm in diameter stamped from them. The surfaces were wiped with a dry tissue and bonded between two cylindrical test pieces using a polyamide cured epoxide adhesive and immediately placed in a sealed container at 100% RH for the adhesive to cure. After 16 h the specimens were broken on an Instron Universal Test Machine with minimum delay. Recovered values were measured after the panels had dried out at room temperature and humidity for 7 days. Clearly, it is unlikely that the values reported represent the minimum bond strengths, as some drying out is almost inevitable, but the values are directly comparable. 

The effect of silanes on the bond strength of two epoxide adhesives to glass is shown in Table 13. The test mode was that of Sandwich Butt Tensile in which a glass disc was bonded between two aluminium specimens in the form of a sandwich, and the resulting composite specimen broken on an Instron Universal Test Machine. Clearly in such a composite test specimen, alignment is important and there are many potential sites and modes of failure. 

Sharma, F. and Sherman, P. (1973). Evaluation of some textural properties of foods with the Instron Universal Testing Machine. J. Texture Studies 4, 344-352. 

The most common solids rheometers are of the universal testing machine (UTM) type (Gunasekaran and Ak, 2002). Such an instrument comprises a horizontal stationary base-plate and a crosshead, above the base-plate, that can move up or down vertically at a variable constant speed (Figure 22.8). The crosshead incorporates a load cell for measuring and recording force. The crosshead speed, position and direction of movement relative to the base-plate are accurately controlled and recorded. 

Figure 22.8. Schematic diagram of a universal testing machine (UTM)-type solids rheometer. (Reproduced with permission from Gunasekaran and Ak, 2002.)...

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