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Sacrificial Part
A sacrificial part is a part of a machine or product that is intentionally engineered to fail under excess mechanical stress, electrical stress, or other unexpected and dangerous situations. The sacrificial part is engineered to fail first, thus breaking the serial connection and protecting other parts of the system downstream. Examples Examples of sacrificial parts include: * Electrical fuses * Over-pressure burst disks * Mechanical shear pins * Galvanic anodes * Pyrotechnic fastener * Fusible plug * Some leader lines used in angling Angling (from Old English ''angol'', meaning "hook") is a fishing technique that uses a fish hook attached to a fishing line to tether individual fish in the mouth. The fishing line is usually manipulated with a fishing rod, although rodless te ... See also * * * Mechanical engineering Safety equipment References {{Tech-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Structural Failure
Structural integrity and failure is an aspect of engineering that deals with the ability of a structure to support a designed structural load (weight, force, etc.) without breaking and includes the study of past structural failures in order to prevent failures in future designs. Structural integrity is the ability of an item—either a structural component or a structure consisting of many components—to hold together under a load, including its own weight, without breaking or deforming excessively. It assures that the construction will perform its designed function during reasonable use, for as long as its intended life span. Items are constructed with structural integrity to prevent catastrophic failure, which can result in injuries, severe damage, death, and/or monetary losses. ''Structural failure'' refers to the loss of structural integrity, or the loss of load-carrying structural capacity in either a structural component or the structure itself. Structural failure is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mechanical Stress
In continuum mechanics, stress is a physical quantity that describes forces present during deformation. For example, an object being pulled apart, such as a stretched elastic band, is subject to ''tensile'' stress and may undergo elongation. An object being pushed together, such as a crumpled sponge, is subject to ''compressive'' stress and may undergo shortening. The greater the force and the smaller the cross-sectional area of the body on which it acts, the greater the stress. Stress has dimension of force per area, with SI units of newtons per square meter (N/m2) or pascal (Pa). Stress expresses the internal forces that neighbouring particles of a continuous material exert on each other, while ''strain'' is the measure of the relative deformation of the material. For example, when a solid vertical bar is supporting an overhead weight, each particle in the bar pushes on the particles immediately below it. When a liquid is in a closed container under pressure, each par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Surge
In electrical engineering, spikes are fast, short duration electrical transients in voltage (voltage spikes), current (current spikes), or transferred energy (energy spikes) in an electrical circuit. Fast, short duration electrical transients (overvoltages) in the electric potential of a circuit are typically caused by * Lightning strikes * Power outages * Tripped circuit breakers * Short circuits * Power transitions in other large equipment on the same power line * Malfunctions caused by the power company * Electromagnetic pulses (EMP) with electromagnetic energy distributed typically up to the 100 kHz and 1 MHz frequency range. * Inductive spikes In the design of critical infrastructure and military hardware, one concern is of pulses produced by nuclear explosions, whose nuclear electromagnetic pulses distribute large energies in frequencies from 1 kHz into the gigahertz range through the atmosphere. The effect of a voltage spike is to produce a correspondin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fuse (electrical)
In electronics and electrical engineering, a fuse is an electrical safety device that operates to provide overcurrent protection of an electrical circuit. Its essential component is a metal wire or strip that melts when too much current flows through it, thereby stopping or interrupting the current. It is a sacrificial device; once a fuse has operated, it is an open circuit, and must be replaced or rewired, depending on its type. Fuses have been used as essential safety devices from the early days of electrical engineering. Today there are thousands of different fuse designs which have specific current and voltage ratings, breaking capacity, and response times, depending on the application. The time and current operating characteristics of fuses are chosen to provide adequate protection without needless interruption. Wiring regulations usually define a maximum fuse current rating for particular circuits. A fuse can be used to mitigate short circuits, overloading, mismatched loads ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Burst Disk
A rupture disc, also known as a pressure safety disc, burst disc, bursting disc, or burst diaphragm, is a non-reclosing pressure relief safety device that, in most uses, protects a pressure vessel, equipment or system from overpressurization or potentially damaging vacuum conditions. A rupture disc is a type of sefe device because it has a one-time-use membrane that fails at a predetermined differential pressure, either positive or vacuum and at a coincident temperature. The membrane is usually made out of metal, but nearly any material (or different materials in layers) can be used to suit a particular application. Rupture discs provide instant response (within milliseconds or microseconds in very small sizes) to an increase or decrease in system pressure, but once the disc has ruptured it will not reseal. Major advantages of the application of rupture discs compared to using pressure relief valves include leak-tightness, cost, response time, size constraints, flow area, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shear Pin
A shear pin is a mechanical detail designed to allow a specific outcome to occur once a predetermined force is applied. It can either function as a safeguard designed to break to protect other parts, or as a conditional operator that will not allow a mechanical device to operate until the correct force is applied. As safeguards In the role of a mechanical safeguard, a shear pin is a safety device designed to shear in the case of a mechanical overload, preventing other, more expensive or less-easily replaced parts from being damaged. As a mechanical sacrificial part, it is analogous to an electric fuse. They are most commonly used in drive trains, such as a snow blower's auger or the propellers attached to marine engines. Another use is in pushback bars used for large aircraft An aircraft ( aircraft) is a vehicle that is able to flight, fly by gaining support from the Atmosphere of Earth, air. It counters the force of gravity by using either Buoyancy, static lift or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galvanic Anode
A galvanic anode, or sacrificial anode, is the main component of a galvanic cathodic protection system used to protect buried or submerged metal structures from corrosion. They are made from a metal alloy with a more "active" voltage (more negative reduction potential / more positive oxidation potential) than the metal of the structure. The difference in potential between the two metals means that the galvanic anode corrodes, in effect being "sacrificed" in order to protect the structure. Theory In brief, corrosion is a chemical reaction occurring by an electrochemical mechanism (a redox reaction).Shrier 10:4 During corrosion of iron or steel there are two reactions, oxidation (equation ), where electrons leave the metal (and the metal dissolves, i.e. actual loss of metal results) and reduction, where the electrons are used to convert oxygen and water to hydroxide ions (equation ): In most environments, the hydroxide ions and ferrous ions combine to form ferrous hydroxid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrotechnic Fastener
A pyrotechnic fastener (also called an explosive bolt, or pyro, within context) is a fastener, usually a nut or bolt, that incorporates a pyrotechnic charge that can be initiated remotely. One or more explosive charges embedded within the bolt are typically activated by an electric current, and the charge breaks the bolt into two or more pieces. The bolt is typically scored around its circumference at the point(s) where the severance should occur. Such bolts are often used in space applications to ensure separation between rocket stages, because they are lighter and much more reliable than mechanical latches. In applications that require safety, precision and reliability, such as the aerospace industry, pyrotechnic fasteners are triggered using exploding bridgewire detonators, which were themselves later succeeded by slapper detonators. Classical blasting caps are generally avoided for such usage. More recent developments have used pulsed laser diodes to detonate initiators ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fusible Plug
A fusible plug is a threaded cylinder of metal, usually bronze, brass or gunmetal, with a tapered hole drilled completely through its length. This hole is sealed with a metal of low melting point that flows away if a predetermined high temperature is reached. The initial use of the fusible plug was as a safety precaution against low water levels in steam engine boilers, but later applications extended its use to other closed vessels, such as air conditioning systems and tanks for transporting corrosive or liquefied petroleum gases. Purpose A fusible plug operates as a safety valve when dangerous temperatures, rather than dangerous pressures, are reached in a closed vessel. In steam boilers the fusible plug is screwed into the crown sheet (the top plate) of the firebox, typically extending about into the water space above it. Its purpose is to act as a last-resort safety device in the event of the water level falling dangerously low: when the top of the plug is out of the wat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fishing Line
A fishing line is any flexible, high-tensile cord used in angling to tether and pull in fish, in conjunction with at least one hook. Fishing lines are usually pulled by and stored in a reel, but can also be retrieved by hand, with a fixed attachment to the end of a rod, or via a motorized trolling outrigger. Fishing lines generally resemble a long, ultra-thin rope, with important attributes including length, thickness, material and build. Other factors relevant to certain fishing practice include breaking strength, knot strength, UV resistance, castability, limpness, stretch, memory, abrasion resistance and visibility. Traditional fishing lines are made of silk, while most modern lines are made from synthetic polymers such as nylon, polyethylene or polyvinylidene fluoride ("fluorocarbon") and may come in monofilament or braided ( multifilament) forms. Terminology Fishing with a hook-and-line setup is called angling. Fish are caught when one is drawn by the bait/ lure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angling
Angling (from Old English ''angol'', meaning "hook") is a fishing technique that uses a fish hook attached to a fishing line to tether individual fish in the mouth. The fishing line is usually manipulated with a fishing rod, although rodless techniques such as handlining also exist. Modern angling rods are usually fitted with a fishing reel that functions as a crank (mechanism), cranking device for storing, retrieving and releasing out the line, although Tenkara fishing and traditional cane pole fishing are two rod-angling methods that do not use any reel. The fish hook itself can be additionally weighted with a denser fishing tackle, tackle called a sinker (fishing), sinker, and is typically dressed with an appetizing bait (luring substance), bait (i.e. hookbait) to attract and entice the fish into swallowing the hook, but sometimes an inedible fake/imitation bait with multiple attached hooks (known as a fishing lure, lure) is used instead of a single hook with edible bait. Som ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mechanical Engineering
Mechanical engineering is the study of physical machines and mechanism (engineering), mechanisms that may involve force and movement. It is an engineering branch that combines engineering physics and engineering mathematics, mathematics principles with materials science, to design, analyze, manufacture, and maintain mechanical systems. It is one of the oldest and broadest of the List of engineering branches, engineering branches. Mechanical engineering requires an understanding of core areas including mechanics, Analytical dynamics, dynamics, thermodynamics, materials science, design, structural analysis, and electricity. In addition to these core principles, mechanical engineers use tools such as computer-aided design (CAD), computer-aided manufacturing (CAM), computer-aided engineering (CAE), and product lifecycle management to design and analyze manufacturing plants, industrial equipment and industrial machinery, machinery, HVAC, heating and cooling systems, transport systems, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
