I am travelling overseas and witnessed a roadside welding facility where the workers were not wearing any type of eye protection. As most people know, this is a sure-fire way to lose your eyesight permanently… My Concerns Regardless of the country or region in which you live, it is critical that you promote safe working standards for your employees. […]
Category Archives
Plastics Technology
Calculating Cooling Time…
I just received this question… Vishal How do I estimate the cooling time? I located a chart referencing a proportionality constant of a polymer, is this the right way? My Response There are many helpful charts and factors, but these use too many assumptions and are just ways to avoid proper circulations. Proper cooling time estimations contain the […]
Getting a Spotting Press…
I received this question over the weekend… Jason A friend of mine recommended I get a spotting press for the molding department. What are their uses and should I consider getting one? My Response A spotting press is great for checking the parting line. This is a large hydraulic press specifically designed to open and […]
Calculating Apparent Shear Rate…
I received this question form a colleague through Linked-In last week… Colleague How do I calculate the flow rate of the polymer from the known gate cross-section area? My Response The formula for the appearant shear rate through a rectangular gate is as follows: Appearant Shear Rate = (6 x Q) / (W x H x H) Q […]
Problems with Drool…
I received this question the other day… AS We are having problems with material leakage between the nozzle and the sprue. Is there some way we can adjust this? Note: after some further questioning, it was determined that sprue break was not being used, the nozzle position has been aligned, and the diameter and radius are correct. […]