Batch Calculation Questions and Answers

Answer: C

Correct answer: 1 and 2 only

Statements 1 and 2 are correct: specific gravity is read with a hydrometer or from a weighed measure, and adding water lowers it. Statement 3 is wrong - a deflocculant lowers the *viscosity* at a given solids content and leaves the specific gravity essentially unchanged, since it is added in fractions of a per cent. Confusing the two is why a slip is sometimes thinned with water when it needed deflocculant instead.

Answer: D

Delivered moisture varies from load to load and is the one input that changes without anyone altering the recipe. Checking it on receipt and correcting the weighing is the routine safeguard. Nothing else in the recipe changes without a decision being taken.

Answer: A

Correct answer: True

A batch error rarely announces itself: the materials look right, the slip pours, the piece forms and dries. The consequence appears at the kiln as a shift in shrinkage, colour, porosity or fired strength - days later, on a whole batch, with the cause several steps upstream. That is why weighings are checked at the time and recorded, rather than being reconstructed afterwards.