Knit Shield gasket performance
The metal mesh construction provides excellent EMI/RFI protection because
of the metal-to-metal contact and the ability of the mesh to cut through surface
films on mating surfaces, thus reducing surface resistivity
to micro-ohm-centimeter levels. The continuity of
the knitted mesh wire gives the gasket high
internal conductivity, as well. The inherent
resiliency of the knitted mesh makes it ideal for
applications in sheet metal enclosures. The
elastomer core provides a seal against rain,
ventilated air, dust and other environmental
Additional performance, tolerance, and material
data, click here.
Knit Shield gasket materials
Knit Shield gaskets are
constructed of knitted wire mesh strips which are calendered
to close tolerance cross-sections. The metal
mesh material can be Monel (nickel-copper alloy) ,
SnCuFe ( tin-plated copper-clad steel), tin-plated
phosphor bronze, aluminum, or stainless steel.
The most common wire materials are Monel, which
combines excellent EMI/RFI protection, high tensile
strength and resiliency, and high resistance to
oxidation, and SnCuFe, which offers best shielding
performance at lower frequencies, especially with
respect to magnetic fields. Aluminum mesh is
occasionally used when the mating surfaces are
aluminum. Any metal wire can be fabricated
into a Knit Shield mesh gasket depending
on the customer's requirements. Choices for
elastomer materials are neoprene sponge, neoprene
solid, silicone sponge, silicone solid, and others.
Knit Shield gasket mounting
Typically rectangular and round cross-section
gaskets are mounted into a channel. The
channel holds the gasket in place by sidewall
friction and prevents the gasket from being over
compressed. Alternatively the gasket is held
in place in tight fitting slots or bonded in place using an
adhesive. Single-round gaskets-with-fin and
double-round gaskets-with-fin are held in place by
clamping the fin section down under a metal strip,
using an adhesive, or by riveting,
spot-welding or adhesive bonding. Both
rectangular gaskets and round-gaskets-with-fin can
be supplied with attached pressure sensitive
adhesive tape to ease installation.
Knit Shield gasketing selections and
How to Order
Gasket cross-sections, round
and round-with-fin, are available in diameters from .062"
to 1". Rectangular cross sections are available
in sizes from .062" to 1" square. Metal strip gaskets come
both with an elastomer sponge core and as an all-metal strip
gasket. All are available on spools of any continuous
length. To view the Knit Shield Metal Strip Gasket Selection
Guide, click here. To order, specify the part number
from the appropriate selection table and state the length
required. For other sizes and/or materials not shown in the
tables, consult our Applications Engineering Department at
Tel: (508) 880-0987 Fax: (508) 880-0334
or E-mail: firstname.lastname@example.org, email@example.com
Shielding Effectiveness of Knit Shield
(tests based on MIL-STD 285)
|| Attenuation (dB)
Monel wire - QQ-N-281, Class A, .0045" dia.
SnCuFe wire - ASTM B 520, .0045" dia.std.
Aluminum wire - AMS 4182, Alloy 5056, .005" dia.std.
Stainless Steel wire - Alloy 304, .0045",
Other wire diameters available.
Neoprene Sponge - MIL-R-6130 B, Type. II, Grade A,
Neoprene Solid - MIL-R-6855, Class II, Grade 40
Silicone Sponge - AMS-3195
Silicone Solid - ZZ-R-765, Class 2B, Grade 40