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Thus when the 100 kg block (solid calculation) is filled with liquid it contains a mass of only 94 kg. The 6 kg, has to be supplied from a "riser" or "feeder" during solidification - thus the solid object now has a mass of 100 kg. The method is a system to deal with the volume loss during solidification. This (technically) is not an allowance.
A bronze casting showing the sprue and risers. A riser, also known as a feeder, [1] is a reservoir built into a metal casting mold to prevent cavities due to shrinkage.Most metals are less dense as a liquid than as a solid so castings shrink upon cooling, which can leave a void at the last point to solidify.
The two main gate systems are manually trimmed gates and automatically trimmed gates. The following examples show where they are used: Sprue gate: Used for large components, the gate mark is visible in component and no runner is required. e.g.: bucket molding (backside cylindrical gate mark visible and can be felt).
It is important to keep the size of the gating system small, because it all must be cut from the casting and remelted to be reused. The efficiency, or yield, of a casting system can be calculated by dividing the weight of the casting by the weight of the metal poured. Therefore, the higher the number the more efficient the gating system/risers ...
The sprue is a large-diameter channel through which plastic flows, usually around the edges of the part or along straight lines. The runner is a smaller channel from the sprue to the individual part. An analogy may be found in a water system that employs a water main (sprue) and smaller pipes (runners) to individual houses.
Iddq testing is a method for testing CMOS integrated circuits for the presence of manufacturing faults. It relies on measuring the supply current (Idd) in the quiescent state (when the circuit is not switching and inputs are held at static values).
Power gating: This technique uses high Vt sleep transistors which cut-off a circuit block when the block is not switching. The sleep transistor sizing is an important design parameter. This technique, also known as MTCMOS, or Multi-Threshold CMOS reduces stand-by or leakage power, and also enables Iddq testing.
They can also be used as transduction elements, converting the output of another sensor, which generates a strain or temperature change from the measurand, for example fiber Bragg grating gas sensors use an absorbent coating, which in the presence of a gas expands generating a strain, which is measurable by the grating.