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General Features
Band and housing are stainless steel, regardless of the screw
type ordered.
Welded Construction is used in all Murray premium grade
full-size clamps. Four electronically controlled spot welds
permanently join the housing to the band. The result is an
assembly that efficiently translates the installation torque
to sealing power. Welded construction also means no tabs or
interlocked pieces that may invite crevice corrosion.
Hex head screws with screwdriver slot are either 5/16” hex
(Type F clamps) or 1/4” hex (Type I and M clamps). Screws are
available in heat-treated carbon steel, that is double plated with
zinc plus trivalent chromate, heat-treated 400 Series Stainless
Steel, 300 Series Stainless Steel, or in 316 Series Stainless Steel.
Murray’s engineers are continuously searching for more cost
effective clamping solutions for our customers’ applications.
New designs and constructions are evaluated and introduced
as the need arises.
Availability of Other Worm Gear
Clamp Styles
For budget applications, Murray offers mechanically assembled
stainless clamps and carbon steel clamps with plated bands,
housings and screws.
Our 1/2” Wide Band vs.
Our Competitors’ 9/16” Wide
Band Design
Will a 9/16” wide band clamp seal better than a 1/2” wide
band clamp?
No. Assuming equal clamp efficiencies and equal application
torques, the sealing pressure exerted by a 9/16” band clamp will
be lower than that generated by a 1/2 ” band clamp, because the
sealing force is distributed over a larger area.
What does actual test data show about the sealing
effectiveness of 1/2” wide vs. 9/16” wide band clamps?
Comparison of Murray’s 1/2” wide band clamps to a competitors’
9/16” wide band clamps with mechanically attached housings
show significantly less sealing power generated by the 9/16”
wide band clamps. A significant portion of the tightening torque
in mechanically attached housing clamps is consumed when the
housing “seats itself” during tightening, leaving less tightening
energy available to generate sealing power. In the Murray
welding construction, the spot welds provide a rigid permanent
joint between housing and band, allowing relatively more of
the tightening force to be directed toward producing an
effective seal.
Isn’t a 9/16” wide band clamp physically stronger than a 1/2”
wide band clamp?
No. Three piece design 9/16” wide band clamps have a
mechanically attached housing that fits into a large cutout
in the band. Compared to the Murray welded design, the 9/16”
wide band clamp may have as much as 65% less cross sectional
material available in this critical housing-to-band joint area,
which means less material to carry the load. The large band
cutout in the mechanically attached clamp is the “weak link”
in the design.
Does spot welding lead to corrosion?
No. Tests show that the spot welds in Murray clamps are no more
susceptible to corrosion than the base stainless steel from which
the clamps are made. Murray’s welded construction eliminates
the tabs and interlocked feature that favor crevice corrosion in
mechanically assembled clamps.
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Phone: 410-771-0380
sales@murraycorp.com
www.murraycorp.com
GENERAL INFORMATION ON MURRAY
WORM GEAR CLAMPS