Mechanical load is the physical stress on a mechanical system or component. Loads can be static or dynamic. Some loads are specified as part of the design criteria of a mechanical system. Depending on the usage, some mechanical loads can be measured by an appropriate
test method
A test method is a method for a test in science or engineering, such as a physical test, chemical test, or statistical test. It is a definitive procedure that produces a test result. In order to ensure accurate and relevant test results, a test ...
in a laboratory or in the field.
Vehicle
It can be the external mechanical resistance against which a machine (such as a motor or engine), acts.
American Heritage Dictionary of the English Language
''The American Heritage Dictionary of the English Language'' (''AHD'') is an American English, American dictionary of English published by Boston publisher Houghton Mifflin Harcourt, Houghton Mifflin, the first edition of which appeared in 1969. ...
. The load can often be expressed as a curve of
force
In physics, a force is an influence that can change the motion of an object. A force can cause an object with mass to change its velocity (e.g. moving from a state of rest), i.e., to accelerate. Force can also be described intuitively as a ...
versus speed.
For instance, a given car traveling on a road of a given slope presents a load which the engine must act against. Because air resistance increases with speed, the motor must put out more
torque
In physics and mechanics, torque is the rotational equivalent of linear force. It is also referred to as the moment of force (also abbreviated to moment). It represents the capability of a force to produce change in the rotational motion of t ...
at a higher speed in order to maintain the speed. By shifting to a higher gear, one may be able to meet the requirement with a higher torque and a lower engine speed, whereas shifting to a lower gear has the opposite effect. Accelerating increases the load, whereas decelerating decreases the load.
Pump
Similarly, the load on a
pump
A pump is a device that moves fluids ( liquids or gases), or sometimes slurries, by mechanical action, typically converted from electrical energy into hydraulic energy. Pumps can be classified into three major groups according to the method the ...
depends on the
head
A head is the part of an organism which usually includes the ears, brain, forehead, cheeks, chin, eyes, nose, and mouth, each of which aid in various sensory functions such as sight, hearing, smell, and taste. Some very simple animals may no ...
against which the pump is pumping, and on the size of the pump.
Fan
Similar considerations apply to a
fan. See
Affinity laws.
See also
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Structural load
A structural load or structural action is a force, deformation, or acceleration applied to structural elements. A load causes stress, deformation, and displacement in a structure. Structural analysis, a discipline in engineering, analyzes the ...
*
Physical test A physical test is a qualitative or quantitative procedure that consists of determination of one or more characteristics of a given product, process or service according to a specified procedure.ASTM E 1301, Standard Guide for Proficiency Testing by ...
References
{{Authority control
Mechanical engineering
Physical quantities
Structural analysis