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www.vibrationmounts.com Phone: 516.328.3662 Fax: 516.328.3365
Spring Mounts – Elliptic Leaf Type (Naval " X " Type)
This type of vibration and shock isolator was designed specifi-
cally for shipboard or mobile applications. They are particularly
suitable to protect delicate shipboard equipment from shock due
to underwater explosions or sudden stoppage of vehicles for
vehicle-mounted equipment.
All materials used are impervious to corrosion and will operate
efficiently under a wide range of temperature, making the units
well-suited for naval or aircraft applications. Their basic design
employs two or more high tensile stainless steel "U" formed
leaves, situated at each end, forming an elliptical shape when
joined together in the center portion with face plates. The spaces
between the "U" formed leaves are filled with a specially devel-
oped polymer or stainless steel mesh.
Nonmetallic collars backed by stainless steel washers are
supplied for load attachment, while providing noise reduction.
Inch size or metric bolts may be used for fastening of the
equipment to the base or foundation.
Low transmitted shock accelerations are obtained by combin-
ing large permitted static deflection in every direction with a high
energy loss within the mount. The high damping efficiency is
obtained by the polymer which has a very low static stiffness. The
load-bearing characteristics are determined by the metal con-
struction of the mountings. These mounts may be used in tension
as well as compression.
The "X" Mount is one of that rare breed that gives both vibration
isolation and shock protection. Its low frequency ensures effec-
tive vibration isolation, except where the resonant frequency of
the surrounding structure may be sympathetic with the mount's
natural frequency. Similarly, care must be taken during transpor-
tation of equipment supported by "X" Mounts.
The main disadvantage of the mount is that transmissibility at
resonance is high. In most applications this is not critical as the
"X" Mounts are placed in areas that do not coincide with its
resonant frequency. This special applications mount may be of
particular interest not only for its improved vibration performance
at low temperature, but also its lower natural frequency at room
temperatures. This may avoid the need of trying to reduce the
natural frequency by means of adding a rubber washer in tandem,
as this procedure also increases the transmissibility at resonance
of the system.
Shock protection of the new design has the added benefit of
durability under repeated shocks at low temperatures.
INSTALLATION OF "X" MOUNTS
Due to the sophisticated nature of the "X" Mounts, it is essential
that they be correctly loaded. Incorrect loading will mean inad-
equate shock protection (this is true even in underloaded situa-
tions).
Bad Practice
Due to the shape and size of the "X" Mount, there is a strong
tendency to use the space created as storage. Needless to say,
• Heavy Machine Tools
• Air Compressors
• Engine Suspension
• Machine Mounting
• Machine Craft Installations
• Laboratory Equipment
• Electric Motors
• Factory Test Gear
• Seat Suspension in Aircraft and
Vehicles
• Radar Communications
Equipment
• Electronic Control Equipment
• Equipment Mountings in Tanks
and Other Military Vehicles
• Bomb and Other Lifting Gear
• Refrigeration Compressors
• Mobile Vehicles
• Fuel Tanks
• Blowers and Fans
• Pumps
any such placement can render the shock protection useless.
Preferred Systems
Mounts supporting the system underneath only, with the center
of gravity in the lower third of the unit, is preferred. When this is
impossible, a fully suspended method should be used. Top
steadies can be used where it is difficult to choose mounts to
support the weight using a fully suspended configuration.
The practice of combining units on one raft is often carried out
to ensure that a suitable loading is obtained. This practice is
especially important for operator-controlled equipment; the seat
can be mounted on the raft as well.
Orientation
Where possible, the horizontal roll axis should be fore and aft,
to minimize equipment movement due to ship roll, but any
orientation is acceptable for shock protection. It is advisable to
place mounts on any one piece of equipment in the same
direction.
TYPICAL APPLICATIONS INCLUDE:
