Jan 11, 2019
It is a surface sensor whose contact surface is formed in the form of a paddle.
This allows a good contact also e.g. on a curved cavity wall.
Normally the temperature sensor is a K-type (NiCr-Ni) probe with a temperature range between -50 °C and +400 °C.
It should be noted that a contact measurement always influences the measurement result and hence is less accurate.
The mold wall temperature can only be measured at one-point in order to obtain useful information.
It is important that the duration of the measuring is sufficiently long.
Sep 20, 2019
Like in the electrical engineering with cabels, the cooling channels in the injection mold may also have parallel connections.
There are two different possibilities to achive parallel cooling.
For the first one, the parallel connections are done directly next to the cooling device.
In order to have a flexible cooling of the mold, multiple cooling devices are needed.
However, sometimes there is only one cooling device available. In this case the flow rate of the cooling device is splitted up using a distributor block.
The second version of a parallel cooling can be found in the mold itself.
One cooling channel is split up in multiple parallel channels. Note that the same flow rate should be given through each of the channels otherwise the effectivity of the channel is reduced.
The advantage of parallel cooling is, that the channels are shorter and the starting situation is the same for each channel.
Especially for multiple cavity molds parallel cooling is a way where identical cooling can be reached for each cavity.
Nov 4, 2019
A cuboid block with a very high length accuracy is called a parallel gauge block. They are used for testing and calibrating measuring instruments, as well as for direct measurement. By sliding the blocks together, also called wringing, different length can be made. The adhesion force holds the gauge blocks together. Steel gauges should not be joined together for more than eight hours as they tend to cold weld.
The total deviation is composed of the dimensional deviation of each individual gauge block additively, therefore, combinations should
consist of the least possible amount of individual gauge blocks.
Gauge blocks are linear gauges with the smallest measurement uncertainties. Calibration at a National Metrological Institute
(NMI), in Germany this is the Physikalisch-Technische Bundesanstalt (PTB) in Braunschweig, uncertainties of a measurement of approximately 20 to 50 nm are achieved.
Measuring technology: A
parallel gauge block with a nominal size of 75 mm.
Related topics:
This information and services are provided by:
This glossary of plastic industry is provided by PLEXPERT Canada Inc.
Dec 9, 2021
In this case, a tolerance to be maintained is described by two parallel planes or straight lines.
These are spaced at the specified distance and are parallel to the specified reference.
A measured value must lie within these planes or straight lines.
For cylindrical moldings, the tolerance zone is formed by a cylinder with the diameter of the specified tolerance value.
The axis of the cylinder needs to be parallel to the reference.
Quality assurance: The axis of the hole must be within a cylinder of 0.01mm.
Related topics:
This glossary of plastic industry is provided by PLEXPERT Canada Inc.
Mar 12, 2020
“Parts, which have been produced from melt by non-cutting molding (e.g. by pressing, compression molding or injection molding) in all side closed molds” are referred
to as molded parts according to DIN 7708, sheet 1 [freely translated].
Thus in injection molding, the end product, which is produced by filling the cavity with molten plastic, is called a molded part.
It should be noted that a possibly existing cold runner is not a component of the molded part.
