Specifications
Materials, finishes, treatments, etc. of DE-STA-CO products are
changed from time-to-time to improve performance or reliability.
These items are, naturally, subject to change without notice. In
the interest of catalog longevity they are not discussed in detail
throughout the catalog pages. As of the date of releasing this on
line document, however, the following specifications were in force
and can be considered reasonably stable.
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FORGINGS
Forged components (notably the squeeze action clamps are made from
C-11141 material and heat treated to RC 28-34 to improve resistance
to bending and create a wear surface for the pivot pins.
CASTINGS
Used for bases on some of the larger clamps, castings are made of
ductile iron, heat treated to properties of steel. They have the
wear resistance of iron together with greater strength and excellent
shock and impact resistance.
HOLDING CAPACITY
The "holding capacity" of DE-STA-CO toggle clamps has
been determined by actual tests. It is defined as the maximum amount
of force which may be applied to the work holding bar, in the closed
position, without creating permanent deformation of the clamp components.
This maximum force is measured at a point closest to the base and
diminishes as the spindle approaches the end of the bar. The rating
for holding capacity should not be exceeded. These values do not
include and "safety factor".
EXERTING OR CLAMPING FORCE
The "exerting force" of our air/oil toggle clamps is well
defined and can be found here. Manually
operated clamps present a series of variables to determine actual
exerting force.
These variables are:
(a)
the force exerted on the handle by the operator;
(b) the point on the handle where this force is applied;
(c) the mechanical advantage in the linkage; and
(d) the point on the work holding bar where the force will be
measured. As a general rule, the mechanical advantage available
throughout the line ranges from 2:1 to 10:1
COMPOSITE
MATERIALS
Clamp components and spindle assemblies are modeled, of Nylon 6/6
with 30% glass fiber reinforcement. Removable yellow clamping pads
on "BC" and "CC-Y" models are urethane. The
spring on "BC" models is music wire. Nylon is inert to
most organic chemicals such as esters, ketones, alcohols, and hydrocarbons.
It resists alkalis and salt solutions, but is attacked by phenols,
formic acid, strong mineral acids and oxidizing agents. Maximum
temperature is 170° F.
ALUMINUM
A number of the squeeze action clamps are available in high strength
aluminum alloy selected for the highest and most stable combination
of strength with impact resistance, dimensional stability and fatigue
endurance. Jaws are forged; handles are cast and heat treated.
PLATING
the plating on most steel toggle clamp parts is a zinc plating with
a bright finish, which conforms to Government specification QQZ325
Type 1, Class 3. Many cast and forged bases are black oxide finished.
POWER CLAMPS
Power clamps can be actuated by pneumatic pressure or hydraulic
fluid. Most of the cylinders are of tie-rod construction for maximum
strength and have hard chrome-plated or ground stainless steel piston
rods. Rod seals are generally a quad-seal. The small bore cylinders,
through 1 1/8", also have quad-seals for piston seals and the
larger bores have U-cups. The standard cylinder is supplied with
Buna N seals and may be operated over a temperature range of -40°
to +250° F. Also available is a high temperature seal kit with
Viton seals, which extends the temperature range from -20° to
+400° F. It also can be used in service with most of the exotic
fluids.
MISCELLANEOUS
The standard light and medium-duty clamps are made from C-1008 or
C-1010 low carbon, cold rolled steel. The work holding clamp bars
and other components of our medium and heavy-duty clamps are made
from C-1018, a cold finished, low carbon, case hardening steel.
The pivot pins in most of our clamp models are very close-tolerance,
cold-drawn, 430 stainless steel headed rivets. In the heavy-duty
models, hardened and ground replaceable pins are used.
Bushings are made of low carbon steel, case hardened for wear and
serrated on the circumference to ensure non-rotating, long wearing
bearing surface for the pivot pins.
Spindle assemblies are made from cold-drawn bar, Grade 2, and plated
with zinc. The bonded spindle tip is oil-resistant, black neoprene
with a durometer of 70-80 Shore A to provide adequate compressibility
and resiliency.
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