was asked by a beginner in mold industry: What is
difference between Hot Runner Mold &
Normal Mold for injection molding machines? Is hot runner mold
benefited to reduce wastage & increase production?Though
the question is fairly basic, there is quite a range of answers, and those
answers are not simply boiled down to one or two sentences. The
indications, guidelines and factors as well as all the different variations for
use of a "cold runner"
versus a "hot runner"
are going to vary, and would range beyond the scope and ability to answer the
will have to examine your application and choose accordingly, but I will try to
explain briefly some of the advantages to a hot runner solution.
As I currently work for a hot runner company
I see many parts that benefit from this application. Here are a few basic
reasons to look into hot runners:
example of this would be a high cavitation part such as a small cap. A hot runner could
be used for this part creating a good cosmetic gate, no waste, with
a cycle time.
A hot runner can
be used for all thermoplastic resins, and yes even rigid PVC if done
- Less waste -which in turn reduces contamination
- Controlled melt temperature - reduces warping of part as well as plastic
- Great gate vestige - Reduces the need for
- Lower injection pressures - allows for more cavities per mold
- Shorter cycle times - improves production efficiency
would suggest that you strongly consider the SPE training program, hold at the
Chicago Hilton/Indian Lakes Resort, Bloomingdale, Ill. Topics include: plastic injection mold design and
building; plastic materials and processing; extrusion of engineered plastics;
reheat stretch blow molding; injection molding
plastic component failure analysis; thermoplastic elastomers, thermoforming
process technology, plastic part purchasing and quoting; screw design;
snap/press fits and plastics welding; blow mold tooling and part design;
rheology, biopolymers and other new technology. Another alternative to consider
is having someone come to your plant to conduct training.