Metal Textiles knitted
wire mesh exhaust seals and exhaust gaskets provide resiliency, strength in compression,
and a nearly unlimited choice of materials, constructions, or
shapes for specific applications. Most important, they provide
superior performance in hostile environments where other materials
would fail as a result of decomposition or deformation.
Knitted mesh exhaust seals have no seams
or ribs—normally the
weak areas of any seal—so that when used in gasketing
and sealing applications, they provide high-strength uniformity
throughout the sealing area. Unlike woven or braided materials,
knitted mesh consists of a continuous series of interlocking
loops knitted in a tubular form, allowing two-dimensional
movement in the plane
of the mesh. This results in unusual flexibility and resiliency,
even under heavy compression loads and exposure to extreme
Due to its inherent resiliency and strength in
compression, knitted wire mesh also yields to applied force—yet
recovers to nearly its original shape when the force is removed.
Flexibility in Design and Performance
When knitted mesh is combined with other materials, the mesh serves as a
“backbone” support imparting resiliency and strength in compression to the seal.
Because of the wide array of materials available for construction, knitted wire
mesh can also be used to create any number of flexible, resilient gasketing or
seal configurations over a broad range of operating conditions.
Knitted wire mesh seals and gasketing may be used for static joints, as well
as those where there is freedom of positioning in repeated closures. In all of
these applications, conventional materials require periodic replacement. Even
where replacement can be scheduled well in advance of the estimated failure
point, replacement cost and downtime are high.
Seals and Gaskets that Offer Flexibility, Strength,
And Long-Term Performance
Depending on the specific application, knitted wire can be fabricated from almost any
material or combination of materials that can be drawn into wire or filament form. For
extreme environments, the most frequently used material is stainless steel wire.
But other ductile metals, such as aluminum, copper and special alloys, can also be
used-as well as synthetic fibers, polymers and yarns-as either single substrates or configurations
of multiple materials. This wide range of material options permits flexibility
in producing gaskets that can be expressly designed for specific critical applications.
Sealing for some of the world's harshest environments
Metal Textiles has also developed a family of seals which combine knitted wire mesh technology
with a variety of other materials to form unique composites. The resulting composite
seals exhibit characteristics which can be useful in extremely harsh, chemical-process
system environments. These seals are generally die-formed to fit specific applications
within allowable tolerances. Available composite materials include graphite, ceramics,
and other similar fillers.
Typical applications include process valve shaft and stem seals where sealability is
required along with seal resiliency, and temperature and corrosion resistance. Due to
these performance characteristics, Metal Textiles seals are also commonly used in many other
applications and industries, including petroleum and petrochemicals.
Metal Textiles also has the unique capability to integrate elastomers and plastics with knitted
wire mesh technology for extremely hostile-environment applications-including
the kinds of sealing problems encountered with temperatures to 260°C and pressures to
The unique characteristics of knitted wire mesh construction provide the necessary
resilience and mechanical strength to restrict extrusion of the most free-flowing materials
while maintaining excellent memory.
The unique fabrication process used by Metal Textiles makes possible the production of seals,
gaskets, and gland packings in forms, shapes and densities unobtainable by any other
method or material.This process allows the creation of sealing media for virtually any
- Exhaust system gasket seals
Exhaust systems for gasoline, diesel, and gas turbine engines are subjected to temperature
extremes, corrosion, vibration, and thermal shock. Most of the negative effects
of these conditions occur at the seals. Conventional seals simply can not meet these
criteria. In conjunction with leading automotive manufacturers, Metal Textiles has developed
knitted wire mesh designs that exceed them.
- Furnace, oven and boiler joints
Gaskets used in high-temperature sealing for furnaces, ovens, and boilers are tubular
or flat constructions of knitted wire mesh and refractory materials. Generally, the
mesh is knitted with metals or alloys and then covered with fiberglass or a similar
material. Metal Textiles knitted wire gasket constructions are obtainable in any desired length
or as preformed gaskets, and withstand direct exposure to flame, combustion products,
superheated steam, petrochemicals, rapid temperature changes such as those
occurring during start-up, and the oscillatory pressures generated by the combustion
process. Unlike other gaskets, knitted wire gaskets need not be replaced when
removed but can be reused indefinitely, providing additional savings in maintenance
- High-temperature door seals
- Furnace, boiler, and oven doors that must be opened and closed frequently impose
intense demands on gasket materials.The gasket must compress readily to seal the
joint—yet retain its resiliency and integrity under prolonged, repeated use. Knitted
wire has been field documented in controlled tests that exceeded 50,000 openings
and closings without failure.
- Two basic knitted wire configurations have been used for high-temperature door
seals: single or double refractory rope covered with a knitted wire sleeve, and
“tadpole” type, comprising a webbed sleeve of refractory material with a knitted
The sleeve for single or double refractory rope retains a cylindrical rope shape,
reinforces it, and protects it against deterioration due to impact and abrasion.The “tadpole” type provides greater mounting adaptability, increased resiliency, and a
more uniform seal against the escape of gases and vapors under small pressure
- Foundry mold gasketing
- The unique properties of knitted wire provide a sophisticated yet simple solution to
the problem encountered in sealing open-bottom foundry molds used in casting
iron.The molds stand upright on the casting stool, requiring a seal for the spaces
between the mold and the stool in order to chill the molten metal to prevent costly
leakage. Metal Textiles knitted wire formed into a multi-core cable solves this problem.
Consisting of five plain or galvanized steel wire-mesh tubes bound together by a single
knitted wire sleeve, the gasket is compressed between the mold and the stool,
filling all gaps around the joint.The poured metal flashes into the gasket, where it
cools, forming a slag skin, thereby minimizing leakage, waste, and safety hazards.
- Cryogenic system seals
- Cold can often be more stressful on gasket materials than extreme heat, since
the molecular structure of many materials is affected by cold conditions. Ordinary
gasketing materials become rigid, hard, and brittle—and may crack, crumble, or even
shatter on contact with liquefied air or gases. Metal Textiles knitted wire technology
provides a solution to this problem.This design withstands the destructive effects
of cryogenic temperatures, creating a perfect seal yet maintaining resiliency under
the most severe conditions.
- In a typical application of a Metal Textiles gasket in a production-line installation for
quick-freezing hamburger, tadpole gaskets are used on the cover flanges to seal in
the freezing gas when the covers are closed. At the (-170°C) operating temperature,
conventional gasket materials shatter, not only destroying the seal and releasing
gas, but contaminating the food as well. Metal Textiles gasketing retains its integrity at
cryogenic temperatures, removing the threat of contamination and performing its
sealing function indefinitely.
- Similar compositions and configurations are available for use on all types of
cryogenic instruments, machinery, vehicles, and equipment where liquid air, oxygen,
nitrogen, and helium are common media. Knitted wire gaskets provide an effective
seal and remain resilient down to temperatures as low as -195°C.
- Heat resistant-knitted wire mesh dissipates, transfers or resists heat
- High strength and durability-resistant to wear
- Withstands cryogenic temperatures and wear
- Resistant to corrosion, deterioration, and heat at over 500°F and below - 100°F
- Can be compressed, layered, calendared, and wound to present a tortuous path
Typical static and dynamic seals and gaskets to meet a wide range of applications
Knitted wire mesh hightemperature door seals
Custom exhaust seals for a wide variety of automotive, transportation and industrial
Cryogenic mesh and grafoil to meet extreme temperatures and sealing requirements