Exam 17: Plastics Systems

An __________ is a device designed to prevent damage to equipment and personnel. This is accomplished by stopping or preventing the start of certain equipment functions unless a preset condition has been met.

Customers will not accept raw granules because of:

A _____________ is a polymer filtering device. It comes in a variety of designs and shapes which range from circular, flat multi-layered screens to a group of 27 horizontal mesh filtering screens held in a large steel cylinder is the next area the melt passes through. The _________ traps any particles or foreign objects in the polymer stream.

The ____________ rotating knives cut the strands of polymer as they leave the die holes in the Extruder, producing pellets, the product of the Extruder post. The newly formed pellets are carried away and kept from sticking together by a flow of water which is a part of the pellet water system.

Various additives such as _____________ help narrow molecular weight distribution and swell.

The dryer ___________ removes moisture and heat from the pellets.

There are five different pieces of equipment in the dryer/classifier system, which one is not.

The ___________ separates good pellets from over-sized or misshapen pellets.

The discharge side of homogenizer is equipped with a _____ to hold a constant level for better mixing.

The dryer dries pellets using ____________.

A complex device composed of a heated jacket, a set of screws or screw, a heated die, large motor, gear box and a pelletizer.

In its granular and flake form polypropylene has:

The __________ separates trash from the pellet slurry.

It is the function of the _____________ to thoroughly mix the streams of granules, peroxide and additive(s). The ___________ achieves this by stirring its contents with a large spiral auger as the material is moved along by the auger in a trough.

A ____________ is a special type of interlock that controls a set of conditions that must be satisfied before a piece of equipment can be started.

Please sketch a simple flow diagram of a modern plastics finishing facility. Label key equipment.

___________ deal with start up items whereas hardwire interlocks deal with shut down items.

There are two types of interlocks:

The purpose of the extruder is to:

The _________________ system removes pellet water from the pellets and classifies them according to size.