Precision Polymer Engineer, or PPE for short

manufactures high performance elastomer O-rings

for critical applications around the world.

This video shows the complete manufacturing process of

how O-rings are made at PPE.

The UK manufacturing facility and head office is based in

Blackburn, in the North West of England.

The US manfacturing plant is located in Brenham, Texas.

The first step in manufacturing an O-ring is selecting the

correct mould tool.

PPE holds thousands of tools for moulding standard sized O-rings.

The smaller sizes are stored in a computerized system

and larger tools are tools stored in racking,

all ready to use at a moment's notice.

Each O-ring mould is comprised of two halves, a top and bottom.

If the O-ring required is a custom size, the new mould tools

can be be manufactured in-house. This greatly reduces the

time it takes to get the O-rings into production.

The O-ring mould is cut from steel blanks using

a high-precision lathe.

Correct material selection is key to seal performance.

Elastomers derive their performance characteristics

from the ingredients and additives that are in them.

Fillers, additives and other ingredients are mixed into the

elastomer material using a milling machine.

The material is repeatedly passed between two

metal rollers to disperse the ingredients evenly.

Each material grade is unique, based on the combination

and amount of each ingredient used.

The elastomer material arrives at the next stage as a sheet

which is cut into strips and inserted into an extruder.

Once inside, the material is heated up to reduce its

viscosity and forced through a die, which produces

lengths of cord.

The size of the die aperture is carefully selected based on the

finished diameter of the O-ring that's required.

During the moulding stage, the cord is cut to size and placed

into one half of the heated mould tools, which are fixed to

the two platens of the press.

When the two halves of the tool close, the elastomer material

is moulded into an O-ring shape.

It is left in the press for a short length of time to start

the curing process.

When the press opens, the O-ring is carefully removed from

the mould.

This technique of manufacturing O-rings is called compression moulding.

Larger O-rings, up to two and a half metres,

or eight foot in diameter,

are precision moulded on one of Europe's largest moulding

presses at PPE's Blackburn facility.

Once moulded, the O-rings often have excess material around

the sides, where the two halves of the mould meet.

This is known as 'flash'.

In the next stage of production, called 'Finishing', this flash

be removed in a number of ways to produce a perfectly round

O-ring.

Drumming.

The O-rings are placed in a drum of rotating stones which

rub the excess flash off.

Buffing.

Larger O-rings are placed under a buffing wheel.

The abrasive action rubs the flash off.

Cryo.

Small O-rings that are too delicate for any of the

other finishing methods are placed in a metal drum,

this rotates within a cryogenic environment.

Liquid nitrogen cools the elastomer O-rings down until the

flash is brittle and can be removed by shot blasting

with grit.

The de-flashed O-rings are placed in ovens to complete the

curing process.

The length of time they are in the oven depends on the type of

elastomer, but typically ranges from two to eighteen hours.

Once cooled the O-rings are now ready for quality inspection.

Trained operators use 2x magnification,

as stated in ISO 3601 standard, to visually inspect the O-rings for

for visual defects.

The O-rings are measured using optical non-contact measuring

equipment which accurately checks the dimensions of

the finished part.

The O-rings are now ready to be packaged as per the customer's

requirements.

Once bagged and labelled the O-rings are packaged by the

despatch team, ready to be shipped around the world.

So now you know how O-rings are made at PPE, and why our

O-rings are trusted to provide the highest quality and optimal

for critical applications.

To find out more, visit our website at prepol.com.