Description
The point load tester performs a precise determination of the uncorrected point load strength index, denoted as "Is," which is then converted into a point load index standardized to a diameter (De) of 50 mm. This converted value, known as "Is(50)," serves multiple purposes, including rock strength classification and the estimation of parameters such as uniaxial compressive strength (UCS) and rock anisotropy, represented as Ia(50). The device itself comprises several components, including a hydraulic jack equipped with a pressure gauge, a sturdy two-column crosshead frame, and a protective carrying case. When pressure is applied through the hydraulic pump, it displaces a piston carrying the lower conical platen. The pressure is directly measured using a digital pressure gauge. The upper platen is securely attached to the crosshead, and a fixed graduated scale is in place to measure the diameter of the rock sample accurately. This instrument adheres to the procedures outlined in ASTM D5731, ensuring standardized and reliable testing methodologies. The PLT-100 can be supplied with an optional indirect tension Brazilian fixture (ITB-250) for assessing the tensile strength of the specimen.
Specifications
Standard
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ASTM D5731
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Load capacity
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100 kN
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Maximum sample size
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4 inches (101.6 mm)
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Pump pressure
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70 Mpa
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Pressure accuracy
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0.2% FS
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Weight
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25 Kg
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Dimensions
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50 x 30 x 25 cm
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Benefits
Simple test
Direct reading of specimen diameter
Extreme rigidity
Inexpensive instrument
Portable, easy to carry on-site
Attractive alternative to the UCS test because provides similar data at a lower cost
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