u to unilinear

u to Ultra speed welding

U. Symbol for internal energy; ten­sion.
U bolt. (Mech.)A bolt shaped like the letter U tbreaded at both ends; called a "clip" as a spring clip on an auto­mobile.
U clamp. (Mach. Shop) A clamp shaped like the letter U; used for clamping down work on planer beds,. etc.
Udometer. (Phys.) A rain gauge. Ulterior. Being beyond what is seen;intentionally kept concealed
Ultimate. Representing a limit beyond which further progress is impossi­ble.
Ultimate set. (Engin.) The difference between the length of a specimen plate, or bar, before testing and at the moment of fracture, and given in percentage of the length.
Ultimate strength. (Engin.) The high­est unit stress that can be sustained, this occurring just at or just before rupture.
Ultimate tensile strength. The force required to break a piece of tape of a given width using a constant pulling speed. The measurement is usually expressed ingrams for a given width the thickness, but also can be expressed in pounds per unit of cross-sectional area. Ultra. Going beyond what is usual or ordinary.
Ultra centrifuge. A high-speed cen­trifuge for subjecting solutions to forces many times that of gravity and producting conncentration dif­ferences depending on the weight of the molecule. Ultra critical. Extremely critical. Ultra-high frequency. Any fre­quency between 300 and 3,000 MHz.
Ultra-linear. Type of push-pull ouput stage in valve power amplifier employing transformer primary trappings for valve screen grids.
Ultramarine. (Paint.) A light-blue to deep-blue pigment originally made from the powdered mineral lapis lazuli, but now made from kaolin, soda, charcoal, and sulphur.
Ultramicrometer. A micrometer capable of measuring extremely small magnitudes.
Ultra microscope. An instrument that uses scattering phenomena to detect the position of objects too small to be seen by an ordinary mIcroscope. Ultramodern. Very advanced in ideas or techniques Ultra red. Infra red.
Ultrasonic. Mechanical vibrations or waves at frequencies above upper limit of human hearing. Often con­fused with supersonic.
Ultrasound. A sound wave of a fre­quency too high for humans to hear.
Ultra-speed welding. A resistance welding process, wherein two or more welding electrodes are in

ultraviolet to unilinear
simultaneous contact with the mate­rial to be welded, with the welded current commutated successively between the welding electrodes by means 'of a com mutating device in the secondary welding-current circuit.
Ultraviolet. Zone of invisible radia­tions beyond the violet end of the spectrum of visible radiations. Waves are shorter than those of light and characterized by chemical action.
Umber. (Paint.) A chestnut-brown hydrated ferric oxide containing manganese oxide and clay. Burnt umber produces a reddish-brown colour. Both are used as pigments. Unbalanced (line or circuit). System
of connections in which one side of circuit is earthed. Signals conveyed by coaxial cable or other screened lead.
Uncontrolled spin. (Aero.) A spin in which the controls are of little or no use in effecting a recovery.
Underbias. The opposite. of overbias (see "Ocerbias"). When a tape is recorded in at an underbiased set­ting, there will be more high fre­quency response, although the over­all recording level will be lower than at a "normal" bias setting, and dis­tortion may be somewhat higher.
Undercoating. (Allto. Meek.) The spraying of a plastic material on the exposed underparts of an automo­bile to retard corrosion and to deaden noise.
Undercut. (Mach.) Teeth on small gear wheels are said to be undercut when they "thin down" as they approach the root line. (Patmkg.) The reverse of draft on a pattern; i.e., a pattern having proper draft will draw from the sand freely, while, if a surface is undercut, it will pull the sand and break and mold..
Underground cable. (Elec.) A sin­gle or multiple conductor cable sheathed in lead or other water­proof materials, carried in a duct beneath the surface of the ground.
Underlay. (Print.) The process of equalizing the impression on the press by means of inserting spots of paper beneath the type form.
Under-pinning. (Engin.) Excavating under walls or erections, and fill­ing the space with concrete or tim­bering
Under-shot wheel. (Engin.) A water wheel which receives its power from water applied at its bottom.
Under-slung. Having the springs attached to the underside of the axles instead of resting on them, as an underslung wagon or auto­mobile.
Under-writer. (Elec.) Name given to representative of an inspection organization who examines elect­rical installations for life and fire hazards.
Undulatory movement. (Aero.) A rising and falling as if on waves.
Uniform load. (Engin.) Includes the weight of the structure itself and any load evenly spread over it.
Unilateral tolerance. An allowable variation plus or minus from a basic dimension, but not both, e.g., 5.250"-.002".
Unilinear. Comprising a single line. A musical waveform, no ma'tte how complex or however many instru­ments may be playing together, is essentially a single undulating line
.