Abstract: An apparatus connects first and second conduits that convey a flow of gas. The apparatus includes a first flange element fixed to the first conduit, and a second flange element fixed to the second conduit. The flange elements are coupled together to permit fluid communication in an internal environment between the first and second conduits. At least one port is intermediate the flange elements to deliver a flow of purge gas therebetween. The at least one port may be located within a purge gas channel arranged in one of the flange elements. A pressure gradient of the flow of purge gas may substantially prevent at least one of fluid egress from the internal environment and fluid ingress from an external environment. Purge gas distribution systems and related methods are also described.

Abstract: Apparatus and method for obtaining accurate sonic input data from a metallurgical furnace, for accomplishing accurate control of a lance injecting oxygen and/or other substances into the melt. A remotely located hydrophone is placed in sonic communication with a liquid circuit cooling the lance. Sound levels and frequencies are picked up through the liquid, and transmitted to a programmable logic controller which generates control signals operating the lance. An associated real time analyzer compares the sonic signature of the input data to predetermined sonic signature data retained in memory, and adjusts lance operation through the programmable logic controller accordingly in order to operate the furnace optimally. Sonic transmission is more accurate, and the hydrophone is more protected from the harsh furnace environment due to its remote location and employment of liquid sound transmission, when compared to other microphone arrangements.

Abstract: A crane has a generally horizontally disposed main boom arm centrally pivotally mounted on a turret supported for rotation atop a central column. The main boom arm supports a load at one end and a counterweight at its other end. The main boom arm load support end has a depending vertical arm, linked in parallelogram fashion with the turret, and with a lower rotatable load carrying swing arm movable through a full 360.degree. arc without interference with the column and turret. The column may be mounted on a dolly. A rack and worm pinion arrangement are provided on either the main boom or the counterweight for adjusting the distance of the counterweight from the column and turret, thus to balance the crane in a vertical plane.