Install Instructions

Viega IM-MTL 0612
724607
6
2. SEALS AND GASKETS
2.1 EPDM Sealing Element
Operating temperature:
0°F to 250°F (-18°C to 120°C)
Viega Metal Systems press fittings are
manufactured with a high-quality EPDM
sealing element installed at the factory.
This sealing element is used mainly
in the applications of potable water,
hydronic heating, fire sprinkler and
compressed air installations. EPDM, or
ethylene-propylene dienemonomer, is
shiny black in color. The EPDM sealing
element is a synthetically manufactured
and peroxidically cross-linked general
purpose elastomer with a wide range
of applications.
It possesses excellent resistance to
aging, ozone, sunlight, weathering,
environmental influences, alkalis and
most alkaline solutions and chemicals
used in a broad range of applications.
The EPDM sealing element has
particularly good resistance to hot
water, making it ideal for seals and
gaskets in heating systems, fittings and
household appliances (e.g. washing
machines, pumps, dishwashers).
2.2 FKM Sealing Element
Operating temperature:
0°F to 284°F (-18°C to 140°C)
FKM is well known for its excellent
resistance to petroleum products and
solvents as well as excellent high
temperature performance. The FKM
sealing element is a specialty purpose
elastomer typically installed where
higher temperatures and pressures
are required.
FKM, or Fluoroelastomer, is dull black in
color. It possesses excellent resistance
to aging, ozone, sunlight, weathering,
environmental influences, oils and
petroleum-based additives. Its excellent
resistance to high temperatures and
petroleum based additives makes it
ideal for seals and gaskets in solar,
district heating, low-pressure steam and
compressed air system fittings. In solar
applications it is resistant to heat spikes
up to 356°F.
2.3 HNBR Sealing Element
This sealing element is used mainly for
applications of natural gas, propane,
mixed and manufactured fuel gases in
the vapor state (not in the liquid state).
It is commonly used in fuel oil heating
systems. HNBR, or Hydrogenated Nitrile
Butadiene Rubber, is yellow in color for
easy identification.
Ambient Operating temperature:
-40°F to 180°F (-40°C to 82°C)
HNBR is widely known for its physical
strength and retention of properties
after long-term exposure to heat, oil
and chemicals.
The unique properties attributed to
HNBR have resulted in wide adoption
of HNBR in automotive, industrial and
assorted high performance applications
(i.e. Engine seals, grommets, gaskets;
Fuel system seals and hoses;
Transmission system bonded piston
seals; Oil field packers and rotary
shaft seals).
With its excellent performance for
the most demanding of applications,
HNBR is the ideal choice for
applications needing excellent physical
properties, as well as oil, heat and/or
chemical resistance.
All sealing elements are inserted into
the fitting, using an H1 Grade lubricant
registered with NSF, the USDA and
approved for use under FDA 21 CER.
For specific applicatons, please
contact your local Viega District
Manager or contact Viega
at 1-877-843-4262.
2.4 Viega Flange Gasket
Viega Flange gaskets are an
asbestos-free gasket material
composed of aramide fibers, inorganic
fillers and other asbestos substitutes
that are resistant to high temperatures.
These fibers and fillers are firmly bonded
to high-grade elastomers under elevated
pressure and temperature. The gaskets
do not contain any color pigments. The
material exhibits high tensile strength,
as well as shearing resistance. Other
characteristic properties of the material
are excellent temperature resistance,
stress resistance under high operating
pressure and ease of handling.
The gasket material has a nonstick
top and bottom layer with a low
coefficient of friction. This aids in
dismantling. Additional surface
treatment is not needed in
most cases.