For several thousand years, people searched for easy methods
for carrying liquids, seeds, grains, and other small particulate materials.
Eventually, the old wood bucket was discovered; this was followed by those made
of metal. As useful as those old tools were, they were still cumbersome,
inconvenient, and heavy.
The world of buckets and pails took a leap forward in the
middle of the first industrial revolution with the discovery of plastics that
could be shaped, formed, and configured to produce a wide range of useful
products. A major but common outcome of the discovery was the development of
the plastic pail.
What is a Plastic
For most of us, a pail has one shape, which is that of a
tall cylinder of two to three feet capable of holding between a gallon or three
liters and 13 gallons or 50 liters. They are found in homes, offices,
factories, and industrial operations as a means for carrying liquids such as
fuel and chemicals or granules such as sand, dirt, and saw dust.
There are a few variations to the common plastic pail; some
can even have a top that is sealed and closed. The traditional type of pail has
an open top for easy access and a handle in the shape of a half circle made of
plastic or metal. This version is flexible and useful for a wide variety of
applications and jobs.
The closed head or sealed top version of a plastic pail has
a limited but important use as a container for fuels, acids, chemicals, and
other liquid substances. They have one or two plug holes for pouring their
How Plastic Pails are
The most crucial aspect of a pail is that it can be tightly
sealed, so contents do not escape. That particular requirement was hard to
achieve with the wooden buckets of ancient times.
The modern and technological method for making pails out of
plastic is the use of a process known as blow molding; it is an extremely
useful and productive method for molding and shaping plastic. Blow molding
begins by melting a polymer resin and blowing it into a two sided die.
The molten plastic, referred to as a parison or preform, has
gusts of air forced into it such that it opens into a blown shape and adheres
to the walls of the die. In a few seconds, the parison takes the shape and form
of a pail as it hardens against the walls of the die. Once the resin is evenly
spread, it is allowed to cool before being ejected from the die.
The blow molding process produces thousands of pails per
hour that have the exact dimensions and thickness of the original pail design.
The replicability of blow molding as well as its ability to produce precise
tolerances makes it the perfect method for producing plastic pails.
Materials used to
Make Plastic Pails
The most common material used to produce plastic pails is
actually a group of materials known as thermoplastics; they are exceptionally
durable, pliable, ductile, and resistant to acids, chemicals, and
deterioration. Thermoplastics that are most commonly used are polyethylene (PE), polyvinyl
chloride (PVC), and polystyrene (PS); they are used for the production of