sink mark

sink mark

[′siŋk ‚märk]
(engineering)
A shallow depression or dimple on the surface of an injection-molded plastic part due to collapsing of the surface following local internal shrinkage after the gate seals.
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Worcester City, who stunned the Sky Blues in the first round, will be at home to Chesterfield if they can sink Mark Robins's Scunthorpe United at the second attempt after Saturday's 1-1 stalemate at Glanford Park.
During this special election to fill Jack Murtha's seat, it's been less than surprising to see the mainstream media failing to remind Pennsylvanians just how disdainful is their President towards them, even as he has avoided traveling to the region, lest he sink Mark Critz's campaign ship with his own ballast-filled approval rating.
It can be used to flu in gaps in the scan data or to repair defects from the physical originals--for example, a crack in a historic ceramic piece or a sink mark in a plastic moulding.
However, the increased packing pressure does not provide a complete solution for overcoming sink mark problems or reducing shrinkage.
In fact, the map pocket strengthening flange on the top edge of the map pocket is in excess of 1:1 (thicker than the nominal wall), which is possible only because the unsightly sink mark that would otherwise result is prevented by the gas pressure within the microcellular foam melt.
For example, the severity of sink mark was referenced by its depth, which could be measured with a surface roughness measuring machine [11] or with a micrometer [12].
A sink mark in thin sections is seen to depend on delay time, mold temperature, melt temperature and gas pressure (in order of declining importance).
Sink Mark Analysis -- This analysis uses the filling results as input to locate areas where sink occurs and estimate the depth of each sink mark.
Sink Mark Analysis: For many plastic parts, exterior aesthetics are important.
They are said to improve sink mark removal and reduce weight while preserving structural properties of ABS, LDPE, HDPE, and PP parts injection molded and extruded/coextruded.
Products improve flow, compatibilize mixed/ cycled polymers, reduce molding cycle or increase extrusion rates, and are used for sink mark elimination and improved weld-line strength.
Products improve flow, compatibilize mixed/cycled polymers, reduce molding cycle or increase extrusion rates, and are used for sink mark elimination and improved weld-line strength.