Shielded Metal Arc Welding Guidelines

Shielded Metal Arc Welding (SMAW) or Stick welding is a process which melts and joins metals by heating them with an arc between a coated metal electrode and the workpiece. The electrode outer coating, called flux, assists in creating the arc and provides the shielding gas and slag covering to protect the weld from contamination. The electrode core provides most of the weld filler metal
The power in a welding circuit is measured in voltage and current. The voltage (Volts) is governed by the arc length between the electrode and the workpiece and is influenced by electrode diameter. Current is a more practical measure of the power in a weld circuit and is measured in amperes (Amps).

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Submerged Arc Welding

A Submerged Arc Welding (SAW) option that combined the advantages of AC and DC Submerged Arc Welding was not possible until now.A high speed one-side submerged arc welding process of welding speed up to 1.5m/ min (16mm) has been developed for shipping of double-hull VLCC. In the new process, welding wires and fluxes as same as for a ordinary process are used. Electrode numbers are increased from three to four. Leading two electrodes fuse a root of a groove and form a underside (uranami) bead. Trailing two electrodes shape a good surface appearance bead and penetration. In case of 16mm thickness plate, total 3,000A welding current of leading two electrodes and total 1,500A of trailing electrodes are necessary to obtain good one-side weld. The new system has been practically applied to block assembly lines
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Sieve Plate Tower

Design a distillation column to separate ethylene oxide from ethylene
oxide water system. In this system a small amount of ethylene and traces of
acetaldehyde and formaldehyde are present. Comparing with the quantities
of the ethylene oxide and water present in the system, the amount of
ethylene and others are negligible. So it is considered as a binary system.
The distillation column operates at a pressure of 1 atmosphere pressure
(absolute). The feed entering is a mixture of 193.18 Kg moles of water,
95.133 Kg moles of ethylene oxide. The distillate is 99.9-mole % pure
ethylene oxide and the residue will contain 0.1 mole % ethylene oxide.
sbioinformatics.com

Oil Circuit Breakers

Oil circuit breakers (OCBs) can be a real challenge for thermographers as they are an indirect measurement. Small temperature rises on the outside surface seen by the infrared camera, also known as a thermal imager can represent large temperature rises internally. This means great care must be taken, as a good understanding of surface emissivity and background temperature can be crucial when dealing with temperature rises of a few degrees C. Fortunately, most OCBs are painted with a matte finish, nonmetallic paint and have relatively high emissivities,
approaching 0.95.
This paper presents some OCB thermography data and examines problem severity using the watt loss calculation software developed by Dr. Madding and presented at InfraMation 2001. Post mortem photos of an OCB’s internals also lend strong validation to the calculation and the calculation software.
Using the calculation software is outlined and the procedures discussed, such as geometrical, thermographic and load measurements. Sample calculations are given to show the sensitivity of an OCB’s surface temperature rise to internal electrical resistance and other parameters. As a matter of further interest we add a lightning arrester power loss calculation.
Keywords: Infrared thermography, lightning arrester, heat transfer, convection, radiation, oil circuit breakers, watt
loss, power loss, internal electrical resistance, thermal balance, condition based maintenance, predictive
maintenance.
flirthermography.com

Circuit for a clock/calculator Incrementing signal hold

A watch/calculator is disclosed which employs a holdcircuit to hold clock incrementing pulses when datafrom the clock is transferred to calculator circuitry oran arithmetic operation is performed on the data. Whenthe time data is returned from the calculator circuitry tothe clock circuitry or the arithmetic operation is com-pleted, the hold circuit releases any held incrementingsignal so that an increment signal is not lost, even whenthe time data is momentarily out of the clock circuitryin the calculator circuitry or other operations are beingperformed on the time data. Thus, when the time data isreturned to the clock circuitry or the operation is com-pleted, the data is incremented or updated as it wouldhave been normally
brouhaha.com
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