Schwing SP 750-18 - Glossary of Terms

141
Appendix
SP 500 / 750-15 / 750-18 / 1000 / 1250 Operation Manual
Glossary of Terms
Accumulator
A hydraulic device that stores uid power energy in
much the same way that a capacitor stores electri-
cal energy. Because an accumulator stores energy,
it must be drained and depressurized before work
begins on an actuator or hydraulic system equipped
with an accumulator.
Agitator
A device set in the concrete hopper to keep concrete
moving, which prevents it from setting. It is typically
a rotating shaft to which several paddles have been
mounted. See also: Hopper Grate
AWS D1.1
The code for structural welding with steel, as dened
by the American Welding Society. Sections 3, 5, and
paragraph 9.25 of section 9 apply. See also: Certied
Welder and EN 287-1
Blanking Plate
Also known as a blanking plug or end cap. Its pur-
pose is to prevent material from falling out of the de-
livery system (typically the end hose) when moving a
full boom over personnel or property.
Blockage
If the pump is pushing and concrete fails to come out
at the point of discharge, a blockage is the cause.
The causes of blockages are detailed in section 6.18
of this manual. Blockages can create dangerous sit-
uations by causing high concrete pressure combined
with the sometimes uncoordinated e󰀨orts of untrained
workers to remedy the problem.
Bulk Density
The mass of a substance per volume. For example, 1
cubic foot of air weighs much less than 1 cubic foot
of water. One cubic foot of lightweight concrete weighs
less than 1 cubic foot of steel-entrained concrete. We
could say that steel-entrained concrete has a higher bulk
density than lightweight concrete. All calculations for the
operation manuals and specications of concrete pumps
are based upon 150 pounds per cubic foot, which is the
approximate mass of hard rock (normal) concrete.
Certied Operator
An operator who has been issued a certication card
by the American Concrete Pumping Association.
There are several classes of certication, each relat-
ing to a di󰀨erent category of pump. For an operator to
become certied, he or she must pass tests regard-
ing operation, setup, and cleanout for each category
of pump. They must also pass the safety rules test
common to all certication categories, meet the expe-
rience requirements set forth for each category, and
maintain a safe and clean driving record. Certied
operators are considered qualied operators in their
categories. See also: Expert, Qualied Operator
Certied Welder
As it relates to concrete pumping and this safety man-
ual, a Certied Welder is a person who has applied
for, taken, and passed the American Welding Society
(AWS) or the European Normal (EN) test for structur-
al steel welding. Anyone welding on a concrete pump
placing boom, outrigger, tower, or other device must
be certied to AWS D1.1 sections 3, 5, and paragraph
9.25 of section 9 and/or EN287-1/PREN288-3.
Concrete Pressure
The force per square area that is exerted on the
concrete. The concrete pressure is always a ratio in
direct proportion to the hydraulic oil pressure on the
concrete pump circuit. See also: Maximum Pressure
Conductors
Materials that conduct electricity. Copper, silver, alu-
minum, gold, steel, and water are considered good
conductors of electricity. Air, berglass, rubber, ce-
ramics, and glass are considered poor conductors.
All of these conductors have a resistance to the ow
of electricity, which is measured in terms of ohms per
linear foot. As voltage increases, more current ows
through the same resistance. With high-voltage elec-
tric wires—8000 volts, for example—even poor con-
ductors carry enough current through your body to
ground to kill you. (As little as 35 milliamps can cause
cardiac arrest.) Some conductors, such as air, re-
sist electricity verywell, but if the voltage gets high
enough, current will ow. (Lightning is a good exam-
ple of this.) See also: Electrocution