This part of GB/T 14235 specifies the testing methods for softening point, rotational viscosity, acid number, linear shrinkage and ash content of low temperature pattern wax materials for investment casting and the basic requirements for test reports.
This part is applicable to testing physical properties of low temperature pattern wax materials for investment casting.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 514-2005 Specification for liquid-in-glass thermometers for testing of petroleum products
GB/T 601 Chemical reagent - Preparations of reference titration solutions
GB/T 602 Chemical reagent - Preparations of standard solutions for impurity
GB/T 603 Chemical reagent - Preparations of reagent solutions for use in test methods
GB/T 1800.1-2009 Geometrical product specifications (GPS) - Limits and fits - Part 1: bases of tolerances, deviations and fits
GB/T 6682-2008 Water for analytical laboratory use - Specification and test methods
3 Testing method for softening point
3.1 Overview of testing method for softening point of low temperature pattern wax materials
Place two horizontal specimen discs in a shoulder or conical brass ring, which is heated in distilled water at a certain speed. On each specimen disc there is a steel ball. The softening point shall be the average value of the temperatures measured when the specimens are softened to make the two steel balls on them sink by 25 mm.
3.2 Instruments and apparatus
3.2.1 Rings: two brass shoulder rings or conical rings, with dimensions and specifications shown in Figures 1a) and 1b).
3.2.2 Support plate: flat and smooth brass plate, with a dimension of about 50 mm×75 mm.
3.2.3 Steel balls: two steel balls in a diameter of 9.5 mm, each weighing (3.50±0.05) g.
GB/T 14235.1-2018 The following standards are cited: