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Ease
of Use
The
line pressure of the hydraulic fluid is generated
by pumping up the fluid in the press, which requires
physical labor (work) when using a manual press.
Accordingly, users who need presses with a lower
clamp force or clamp tonnage capacity may still
want to consider using a higher capacity press because
less physical labor will be required to pump the
press up to the desired load or force. As can be
seen from the examples, less work is required to
get substantially the same force out of a 20 ton
press than out of a 12 ton press. The 20 ton press
requires only 60% of the work that is required to
pump a 12 ton press to 10 tons of force.
We
employed this concept with the 40 ton E-Z Press
which uses an oversized hydraulic jack. The normal
constraints on choosing a higher capacity press
are that they tend to be more expensive and in many
cases they are significantly heavier and much larger.
In the case of the ICL
E-Z Press line, we can provide presses up
to 40 tons in capacity weighing 150 pounds and with
a very small footprint.
Work
can also be decreased by the use of leverage. To
reduce the amount of work required to jack a press
to the required line pressure some users employ
a longer handle. Optional extra length handles are
available for 12 and 20 ton E-Z Presses at
modest cost.
Another
means of limiting the physical work involved in
jacking a press up to its rated force or tonnage
is to automate the process. There are two methods
of automating a press. First, it can be driven by
a pneumatic motor which is powered by compressed
air. The advantages of this method are that pneumatic
drives are comparatively light, compact and inexpensive,
and the same unit can be operated anywhere in the
world without regard to differences in electrical
current. Pneumatic systems can be coupled with manually
operated valves to regulate the decompression (bleed
off) rate of the press. A second automation option
is to compress the hydraulic fluid in the press
by means of an electric pump. Hydraulic fluid pumps
driven by electric motors facilitate use of electronic
digital controls that can more precisely regulate
increases and decreases in pressure than can manual
or pneumatic powered systems. However, electronically
controlled systems tend to be considerably heavier,
bulkier and more expensive than systems driven by
a pneumatic motor.
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Sample
Compartment Size Daylight Opening And Platen
Size
The
size of the sample compartment is always an important
consideration when specifying a lab press. Most
of ICLs ergonomic lightweight E-Z Presses
and Air-EZ presses use small 4.5" (114.3mm)
diameter platens and feature daylight openings ranging
from 5 1/2" (139.7mm) to 8 1/4". This
is large enough for all IR or XRF pelletizing and
briquetting applications and for pressing thin films
from polymers, but special applications may require
a larger daylight opening. For larger daylight openings,
a column press is normally the solution. Column
presses feature larger platens and larger daylight
openings, but they are considerably heavier and
bulkier than the ergonomic E-Z Presses and
Air-EZ Presses.

Alternatives
To Lab Presses
For Solid Sampling
There are several alternatives to lab presses for
solid sampling. These include sampling with horizontal
ATR's such as the Dia-Braze (0015-6925),
Split Pea (0015-7463)
and Basics (0015-4713),
diffuse reflection for sampling KBr powder/sample
matrices (see Part No. 0016-4657),
spin casting of thin polymer films from solutions
instead of pressing them with polished anvils (see
Roto-Film), diamond
cells for pressing solid samples (see Part No. 0012-6544)
and decomposition analysis (see High Temperature
High Pressure Cell, Part No. 0007-5227).

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