Abstract: An apparatus for the treatment of an exterior pipe surface includes one or more nozzles or other treating means which are carried by a frame. The frame can be mounted around the pipe to be treated and is capable of moving along the pipe surface in longitudinal direction thereof, due to the provision of travelling wheels. Disclosed are provisions for allowing the apparatus to keep itself in balance on the pipe during operation. Such provisions include detection means (e.g. a pendulum with sensors) for detecting undesired displacements of the frame in circumferential direction of the pipe, and control means (such as e.g. hydraulic cylinders with a common system of hydraulic lines and valves) for adjusting the wheel axes of one or more travelling wheels in angular position, in response to a signal delivered by the detection means.

Abstract: The apparatus for treating and/or cleaning an object, especially a circuit board, with a flood flow of fluid comprises means for moving the object along a path in the apparatus and a number of flood flow devices past which the object is moved on the path, all of which are located above the path. A fluid damming means, preferably a pressing roll contacting the path, may be provided on each of the long sides (the sides transverse to the feed direction) of each flood flow device so that in operation a fluid pool arises around each flood flow device.

Abstract: Apparatus and a process are disclosed for cleaning and/or fluxing circuit card assemblies. The assemblies are moved through an enclosure in which they are sprayed with cleaning and/or fluxing liquid from fenestrated cylinders rotating above and below the path of the assemblies and disposed laterally thereacross. The complex spray impact pattern created by the simultaneous movements of the assemblies and the cylinders effects thorough cleaning and/or fluxing of the assemblies. Separate control of liquid pressure from the cylinders prevents unsoldered components from being dislodged from the assemblies during cleaning and or fluxing.

Abstract: In a method of treating one-side electrogalvanized steel sheets, the uncoated side is contacted with an aqueous pickling solution containing a water-soluble hydroxycarboxylic acid and a water-soluble peroxo compound. In this way, extremely resistant mixed oxides are separated from one-side electrogalvanized sheets, which, otherwise, would lead to stripy yellowish and brownish stains on the uncoated steel surface. In addition, the new metal surface formed is passivated.

Abstract: The present invention provides an apparatus and method for processing a sheet material, for e.g. a photosensitive sheet material, with a flowable process substance. The flowable process substance is distributed via a pliable web which has defined on one of its surfaces a plurality of protrusions which define interconnected fluid reservoirs and distribution channels, and which are in surface-to-surface contact with the sheet material over a substantial portion its surface area while the sheet material is transported relative to such web.

Abstract: A dynamic flood conveyor. The conveyor permits a chemical solution to be applied to the surface of a material such that the solution interacts with the material at a generally uniform rate at each point on the surface of the material. The apparatus promotes laminar flow of the channel solution over the surface of the material and uses segmented rollers to minimize the fluid loss from the flood conveyor.

Abstract: A method and apparatus is provided for chemically treating articles, often with a liquid treatment fluid that is corrosive, while the articles are being delivered along a path through a substantially closed chamber. During treatment, the articles pass through a nip formed between opposed rollers, at least one of which is rotatably driven. Because of the thickness of the articles, at least one roller of the nip must be moved away from the other roller in order for articles to pass through the nip. The roller being moved remains positively driven as it moves away from the nip and remains driven until the nip is again closed, all without interferring with the drive.

Abstract: A method and apparatus is provided for chemically treating articles, often with a liquid treatment fluid that is corrosive, while the articles are being delivered along a path through a substantially closed chamber. During treatment, the articles pass through a nip formed between opposed rollers. Because of the thin flexible nature of the articles, they may tend to wrap around a roller after passing through the nip. The articles are engaged as they pass downstream of the nip and are urged away from the surface of the roller, to continue to follow a predetermined path of travel. In engaging the articles to urge them away from the nip, they are preferably contacted by eccentrically mounted rings, carried by the roller. The rings have portions that protrude away from the surface of the roller that enables them to engage the article.

Abstract: Apparatus for handling potentially dangerous materials such as asbestos comprising a main body portion (3) having a work zone (5) therein into which, in use, the material can be placed. An opening (7) is provided to enable access to the work zone (5) from externally thereof. The apparatus further includes spray means (8) operatively mounted to the main body (3) and operatively connectible to a fluid source. The spray means (8) comprises a plurality of spray heads (8, 8A, 8B, 8C) arranged so as to form a plurality of fluid barriers or curtains which surround the work zone (5) and means (16) is provided for maintaining a pressure differential between said work zone and externally thereof when the apparatus is in use.

Abstract: Apparatus for the surface treatment of strips with liquid, in particular for the pickling of rolled metal strip. The apparatus comprises a pickling vessel (3), through which the strip (10) is advanced, closed by a cover (4). Between the strip (10) and the cover (4) a means is provided which if the strip rises upwards, guides the latter back into the direction of movement. This means can be formed of profiles providing a sawtooth-like configuration. Such profiles may be formed by guide means (11) which are chamfered on the side from which the strip enters.

Abstract: Novel pickling method and apparatus are described. A plurality of parallel side-by-side laterally-spaced wires is passed horizontally from end to end of an enclosed pickling zone and are countercurrently contacted by a wave of hot hydrochloric acid pickling liquor formed by a hydraulic jump and passing through the pickling zone submerging the wires. The pickling zone is enclosed at the sides and top and bottom by solid walls and at the ends by water curtains which prevent the egress of fumes of hydrochloric acid. The pickling zone is followed by a washing zone in the same enclosure as the pickling zone comprising further water curtains and wiper bars. The side walls of the enclosure include depending side walls from an upper enclosure portion and upwardly-opening channels at the upper extremity of side walls of a lower portion into which the depending side walls extend below water baths located in the channels to seal the side walls but permit wires to be restrung.

Abstract: The present invention provides an apparatus and method for processing a sheet material, for e.g. a photosensitive sheet material, with a flowable process substance. The flowable process substance is distributed via a pliable web which has defined on one of its surfaces a plurality of protrusions which define interconnected fluid reservoirs and distribution channels, and which are in surface-to-surface contact with the sheet material over a substantial portion its surface area while the sheet material is transported relative to such web.

Abstract: A method and apparatus for removing particles from a flexible sheet. The sheet is run over a rotating rod, rotating oppositely to the moment of the sheet. The rod is immersed on its lower side in a bath of solvent and excess solvent is removed from the bath and is filtered. Additionally, solvent may be applied to the sheet before it reaches the rotating rod or a negative pressure applied just upstream of the rod sucks away the particles.

Abstract: Apparatus for cleaning printed circuit panels includes a pair of manifolds having closely spaced faces forming a narrow passage therebetween. Transverse slots in the manifold faces supply cleaning liquid to printed circuit panels conveyed through the narrow passage. A high velocity flow of cleaning liquid along the surfaces of the printed circuits effectively clean them during their travel through a relatively short distance in the passage. A cleaning system for printed circuits includes a plurality of stages each of which comprises such cleaning apparatus.

Abstract: The invention refers to an equipment for surface treatment of continuously running strip particularly pickling equipment wherein the strip runs longitudinally through a horizontally arranged container receiving treatment liquid while being closed by means of a lid. For optimizing such equipment particularly for improving the quality of treatment and for minimizing the period of time needed for treatment it is suggested to provide within the container a separate treatment channel (4) which is closed through an intermediate cover (6) and receives treatment medium through nozzle bars (9) and (10).

Abstract: Device for continuous cleaning and/or decontaminating a band of a thermoplastic film comprising a housing (1) where the band (7) follows a sinuous trajectory between return cylinders (8, 10, 40, 41, 9) and is subjected to the action of demineralized and/or distilled water jets projected by nozzles, (20, 43, 45, 22) mounted on spraying ramps (19, 42, 46, 21), the direction of jets being preferably opposite to the feed direction of the band (7).

Abstract: Apparatus for cooling at least two bars travelling in parallel linear paths after having been formed from a larger bar in a rolling mill, comprises a common antechamber for receiving the bars, a cooling water inlet and a cooling water outlet communicating with the antechamber, first and second common nozzle chambers, the first nozzle chamber being arranged for receiving the bars from the antechamber and the second nozzle chamber being arranged for receiving the bars from the first nozzle chamber, each of the nozzle chambers being provided with a respective cooling water inlet communicating with the respective nozzle chamber through a respective equalizing chamber, each of the nozzle chambers containing for each of the bars a respective funnel for guiding the bar and a nozzle for receiving the bar from the funnel, the nozzle having passages for conducting water from the chamber into contact with the bar, communicating with each of the nozzles a respective heat exchanger pipe for receiving a respective one of t

Abstract: A system for the chemical cleaning of metal, for example, the acid pickling of steel, includes one or more tanks containing a corrosive liquid bath in which the liquid is flowed rapidly relative to the metal and held at a temperature in excess of 180.degree. F. The tanks comprise an outer metal shell whose internal wall is protected by a layer of a rubber-like material. In one embodiment the rubber-like layer is protected from the hot corrosive liquid by panels of fiberglass reinforced plastic (FRP) which are overlapped in a shingle pattern. In another embodiment, an inner tub (tank) of FRP floats on a layer of water which is held between the inner FRP tub and the layer of rubber-like material which covers an outer metal shell.

Abstract: Two endless belts are formed of steel mesh. The belts are run side-by-side spiralling into the center of the apparatus, reversed and spirally wound out of the apparatus with the outgoing convolutions interleaved between the incoming convolutions. The belts present an inlet at one side of the apparatus and an outlet at the other side of the apparatus. The web is fed into the inlet and conveyed to the outlet. Two or more spiral sections can be run in tandem.

Abstract: A method and apparatus for removing particles from a flexible sheet. The sheet is run over a rotating rod, rotating oppositely to the moment of the sheet. The rod is immersed on its lower side in a bath of solvent and excess solvent is removed from the bath and is filtered. Additionally, solvent may be applied to the sheet before it reaches the rotating rod or a negative pressure applied just upstream of the rod sucks away the particles.

Abstract: A flitch washer for washing flitches with a high volume of low pressure washing liquid is described. The flitch washer comprises an inner cylinder defining a passageway for the flitches. The passageway has open entry and exit ends. A conveyor is provided for conveying flitches through the passageway. The inner walls of the passageway are provided with high capacity, low pressure nozzles for discharging the low pressure washing fluid into the passageway. An outer cylinder having an axis parallel to the axis of the first cylinder, and bulkheads closing the end spaces between the outer and inner cylinders defines a manifold in communication with the nozzles. A high volume pump supplies washing fluid to the nozzles.

Abstract: A device for cleaning or chemically treating workpieces, particularly printed circuit boards with solutions applied to the workpieces by nozzles comprises a two-part housing, the lower portion of which is supplied with a treatment solution and is communicated with the upper part which is subdivided into two chambers by a separating wall. Each chamber is limited from the upper wall of the housing by a flat perforated wall through which the solution flows to the nozzles formed by elongated slots.

Abstract: The fabric cleaning system for cleaning a fabric such as the wire on a paper machine includes a cleaning station through which the fabric continuously passes. In the station cleaning fluid is directed onto a surface of the fabric, contacts the fabric to remove at least some of the debris and is collected in a collecting chamber. The dirty fluid is cleaned of debris in a cleaner such as a screen and is then returned and re-used to clean the fabric. Preferably the cleaning fluid is applied to the fabric through slots with their outlet openings adjacent the fabric and formed by tapered passages that diminish in height in the direction of the travel of the fabric. Preferably the slots extend the full width of the fabric.

Abstract: In washing an elongated tape with hot water, the tape is fed through a succession of hot-water baths one after another. When the tape is transferred from one bath to the next, the hot water on and in the tape is removed. In each bath, the tape is brought out of and then into the hot water at least one time.

Abstract: A flitch washer includes inner and outer cylinders, the space between which is closed at its ends by bulkheads. The inner cylinder defines a passageway open at an entry end and an exit end. A conveyor is provided for conveying a flitch through the passageway from the entry end to the exit end. Nozzle openings are provided through the inner cylinder into the space. Nozzles and plugs are inserted into the nozzle openings to provide a desired pattern of spray of a washing fluid from the space between the cylinders through the nozzles into the passageway. A filter mechanism is provided for trapping debris and the like removed from the flitches by the washing fluid. The filtered washing fluid is then returned to the space between the cylinders for recycling through the nozzles. The filter and conveyor are oriented so that the conveyor also conveys accumulated debris from the filter to a receptacle for disposal.

Abstract: A method and apparatus for improved settling and handling of sludge in a fused salt bath for treating materials is provided. The apparatus includes a tank divided into a work zone and a salt processing zone, with the salt processing zone having a salt recovery section and a salt heating section. A pumping device is provided which together with adjustable gate means, generate a relatively quiescent flow in the work zone allowing sludge to settle, and a relatively turbulent flow in the salt processing zone and especially the salt heating section, to keep the sludge in suspension.

Abstract: Methods for cleaning in-process wire are developed. In one embodiment a moving string loops around the wire and advances to present a clean surface to remove dirt from the surface of the moving wire.

Abstract: Method and apparatus for removing processing oil from thin sheets of microporous plastic material is comprised of a tank having a liquid zone in its bottom portion which is divided into three sub-tanks having decreasing depths extending across the tank. Heating coils in each sub-tank vaporize the solvent to form a cleaning zone, containing vaporized solvent, above the liquid portion, and condensing coils located at the top of the tank condense the vaporized solvent and deposit it into the deepest sub-tank which also is supplied freash make up solvent when required. A series of rollers feeds the material through the tank, from the side having the shallowest sub-tank toward the side having the deepest sub-tank, while repeatedly passing it between the cleaning zone where solvent is condensed on it to clean it, and the condensing zone where it is cooled to a temperature below the temperature of the vaporous solvent.

Abstract: A continuous article has its surface treated twice by first and second jets of fluids as passing though a tunnel provided on a pass line. A fluid flow is supplied through each of first and second introducing ports into the tunnel where it is converted into each of the first and second jets of fluids, one rushing over the article in the same direction as the article and the other rushing over the same in the opposite direction thereto for effecting surface treatments respectively by the first and second jets of fluid. Each of the first and second jets causes a negative pressure to be developed at each inlet and outlet outlet of the tunnel through which the article enters and exits the tunnel. The negative pressure in turn draws in the ambient air through the inlet and the outlet over the article to thereby provide an air seal at each inlet and outlet, preventing the fluids introduced in the tunnel from escaping outwardly thereof.

Abstract: A method, and components therefore for cleaning and reclaiming silk screens and the like. The method involves the steps, in general, of handspraying silk screens to be cleaned at a nominal water pressure of 3,000 psi plus or minus 300 psi, and this preferably at a water temperature of from 70 to 140 degrees Fahrenheit. The water circulating system is preferably a closed system that is periodically automatically replenished as needed. This saves a volume of water required, and such water is reclaimed by filtering systems. The filtering structure employed comprises a series of classifier screens of progressively reduced mesh and disposed in mutually superposed position. A further filter is in the form of a disposable bag filter made of paper or other suitable material preferably having a pore size of the order of ten microns. Additional filters are employed as needed. The spray cabinet employed has silk screen support bars and clamping means for clamping the screens in sloping condition.

Abstract: Apparatus for continuous ultrasonic cleaning all exposed surfaces of endwise advancing strip material employ an elongated ultrasonic cleaning chamber with entry and exit portals formed near the lower edges of its end walls through which the strip travels into, through and out of the cleaning chamber. Cleaning liquid flows continuously from the cleaning chamber through both portals and an overflow conduit into collection chambers from which it is drained, filtered, cooled and recirculated into the ultrasonic cleaning chamber at a high volumetric flow rate. Two parallel elongated ultrasonic plate diaphragms energized at substantially different ultrasonic frequencies flank the advancing strip immersed well below the free surface of liquid in the cleaning chamber, and sonic waves travel rapidly along the strip, cooperating with nearfield vibratory effects near the plate-liquid interface of both plates to achieve intense and highly efficient cleaning of the strip.

Abstract: Ultrasonic wire cleaning apparatus in which elongated strands of wire are advanced continuously through a bath of acid contained in a tank. Ultrasonic transducers are located in the tank and produce ultrasonic energy which coacts with the acid to effect cleaning of the wire. The transducers are submerged in and are cooled by a separate bath of water located in the tank beneath the acid and are protected against erosion by a rigid plastic plate which separates the acid from the water. Water-filled chambers at the sides of the tank keep the head of the water bath greater than the head of the acid bath in order to prevent the acid from leaking downwardly into the water and contacting the transducers.

Abstract: Papermachine felts and wires are cleaned and maintained by pressurized fluid jets or showers which are oscillated transversely across the felt running direction over a fixed oscillation stroke distance. Superimposed on the fixed stroke distance is a periodic shift of the stroke reference point so that successive oscillations are not terminated at the same point. The oscillation drive mechanism is enclosed within a low pressure, gas-tight housing serviced by a pressure regulated gas supply. A reversible A-C motor is used to drive the mechanism.

Abstract: An assembly of gates is provided at each end of a vat. Two uprights mounted on a lock-chamber floor support respective brackets. Pivoted between the floor and the brackets are gate flaps, the pivot rods of which are fitted in holes in the floor and in the brackets. Each gate flap includes a notch, and the successive gates match successive diameters of elongated elements which travel through the vat. In case of localized excess thickness on an elongated element, the impact causes spontaneous opening of the gate guiding the element.

Abstract: Dynamic flood conveyor. The conveyor permits a chemical solution to be applied to the surface of a material such that the solution interacts with the material at a generally uniform rate at each point on the surface of the material. The apparatus promotes laminar flow of the chemical solution over the surface of the material.

Abstract: A metal product having at least one plane surface, e.g. steel strip, is cooled by means of an aqueous fluid as it moves along a predetermined path by apparatus comprising a wall disposed opposite the plane surface of the product and substantially parallel thereto so as to form a chamber of substantially constant thickness between the plane surface and the wall, at least one aperture in the wall communicating with the chamber for the passage of the aqueous fluid connected to the aperture through the wall. The aperture is connected to a source of the aqueous fluid. The rate of flow of the aqueous fluid and the spacing between the wall and the plane surface are both adjustable.

Abstract: Photoresist baked upon integrated circuit wafers is mechanically stripped therefrom. Wafers are unloaded from boats at the top of an elevator within a vertical housing filled with stripper solution, then deposited on a conveyor and carried through a horizontal housing also filled with stripper. The wafers are sprayed by high pressure stripper pumped through a nozzle at the end of their horizontal travel. The wafers are then transferred to another housing where they are rinsed, dried and, optionally, reloaded.

Abstract: A novel process and apparatus for multistage contacting of two materials advantageously provides high chemical efficiency and low losses of components of one of the materials caused by that material being carried out of the process with the other material. The process comprises contacting, in a series of stages, a first material with a second material containing a component whose concentration therein is reduced by such contact. Replenishment material is introduced to at least one of the stages to compensate for such concentration reduction. The concentration of the component in the second material is highest in one of the stages, and the first material carries a part of the second material out of each stage. The first material is contacted with the second material at least one once in each stage of the series.

Abstract: A rinse tank for rinsing residue from fine apertures in a moving strip of material includes a chamber having an elongated slot. The slot has a length sufficient to span the aperture pattern. Fluid is injected into the chamber and exits through the slot as a fluid curtain substantially normal to one side of the strip. Fluid is also passed over the other side of the strip substantially parallel to the fluid curtain. The combined fluid actions cause the fluid to flow into the small apertures to remove any residue from the apertures.

Abstract: A motorized shower head mechanism is disclosed in which a housing is provided with a track and a trolley, and a motor mounted on the trolley. The trolley is moved along the track by the motor and a shower head which extends through the housing is carried along by the trolley.

Abstract: A printing apparatus for printing on a sheet of paper via a thermal ribbon has a paper feeding device for feeding the sheet of paper; a thermal print head including heat generating elements which are held in pressed contact with the surface of the sheet of paper via the thermal ribbon, the heat generating elements being selectively energized to apply heat to an ink layer of the thermal ribbon to fuse the ink for adherence of the fused ink to the surface of the paper; and a smoothness improving device, disposed upstream of the thermal print head in the direction of feed of the sheet of paper by the paper feeding device, for improving the smoothness of the surface of the paper.

Abstract: Method and apparatus for removing processing oil from thin sheets of microporous plastic material is comprised of a tank having a liquid zone in its bottom portion which is divided into three sub-tanks having decreasing depths extending across the tank. Heating coils in each sub-tank vaporize the solvent to form a cleaning zone, containing vaporized solvent, above the liquid portion, and condensing coils located at the top of the tank condense the vaporized solvent and deposit it into the deepest sub-tank which also is supplied fresh make up solvent when required. A series of rollers feeds the material through the tank, from the side having the shallowest sub-tank toward the side having the deepest sub-tank, while repeatedly passing it between the cleaning zone where solvent is condensed on it to clean it, and the condensing zone where it is cooled to a temperature below the temperature of the vaporous solvent.

Abstract: A method and apparatus for cleaning and conditioning a fabric in which pressurized fluid is directed into a restricted and diminishing passageway formed by the fabric and a member forming an extended nip therewith so that the fluid is forced through the fabric.

Abstract: When cooling hot metal strip, it is known to employ headers which apply continuous curtains of water across the width of the strip. The headers above the strip are inclined to each other so that the curtains extend across the width of the strip and are spaced apart horizontally by a greater distance at one edge of the strip than at the other edge.

Abstract: A cleaner drive assembly used for driving a belt cleaning device such as a shower pipe unit provided in a papermaking apparatus having a sheet forming station including an endless belt to forwardly carry a wet web of paper thereon, the belt cleaning device being used to clean the endless belt by applying streams of liquid to the belt and being movable in opposite directions substantially parallel with the direction of width of the belt. The cleaner drive assembly is adapted to drive the belt cleaning device alternately in the aforesaid opposite directions and comprises a drive unit to produce rotary motions in alternately opposite directions, a rotary-to-axial motion converting unit to convert the rotary motions into reciprocating axial motions, the directions of the reciprocating axial motions being aligned with the opposite directions in which the belt cleaning device is movable.

Abstract: An apparatus for cleaning a continuous, long, linear object in a solvent medium includes an inlet ramp and an outlet ramp for the object, and a tubular guide open at its ends for guiding the long, linear object. The object moves inside the tubular guide along an imposed trajectory in the form of a continuous curve. The tubular guide is provided, adjacent one end, with an inlet for clean solvent medium and, adjacent the other end, an outlet for dirty solvent medium. The solvent medium circulates through the tubular guide in contact with the long, linear object in the opposite direction to the direction of movement of the object through the tubular guide. A device for subjecting the solvent medium to ultrasound is also included. The apparatus is particularly intended to be used for cleaning filiform objects, objects in the form of a strip or objects consisting of unit elements joined together to form a strip.

Abstract: The invention relates to an acid pickling tank for metal strips with a width equal to or greater than 0.50 meter.The tank incorporates an external supporting structure (1) and a metal casing (3) coating internally with rubber (6). The rubber layer (6) is lined internally with large slabs (10a, 10b) of a natural rock of volcanic origin, which has a total SiO.sub.2 and Al.sub.2 O.sub.3 content greater than 60%, a porosity of between 6 and 30% and a relative density of less than 3. At most three slabs (10b) are placed side by side along the width of the tank and at most one slab (10a) is placed along its height. The minimum dimensions of a slab (10a or 10b) are 0.50.times.0.50 meter.The invention is applicable in particular to the pickling of strips of hot-rolled metal sheets.

Abstract: An apparatus for vaporizing a liquid and condensing the vapor includes at least one chamber in which the liquid is vaporized and at least one chamber in which the vapor is condensed. The apparatus has a conveyor inlet channel preferably at one end of the vaporizing chamber, and a conveyor outlet channel preferably at the opposite end of the vaporizing chamber. A conveyor for moving items to be treated through the apparatus extends through the conveyor inlet channel into the vaporizing chamber and out of the vaporizing chamber through the conveyor outlet channel. The apparatus includes a heat emitting device in the vaporizing chamber for vaporizing the liquid therein, and a cooling device in the condensing chamber for condensing the vapor.

Abstract: A method for cleaning cathode and/or anode plates which are obtained in the electrolytic refining of metals and which are lifted in groups suspended on bars or lugs from the electrolytic bath and thereafter the plates are washed by passing in succession through the washing operation individually or in pairs inclined in substantially V-manner with respect to each other. Additionally, three or more plates, inclined away from each other substantially in fan manner, may pass through the washing operation. The flat sides of the plates are sprayed at least partially by nozzles which execute a relative movement along the flat sides.

Abstract: Wire is passed through apparatus having two treatment zones, the first treatment zone containing six wire cleaning heads and the second treatment zone containing two wire cleaning heads. Each cleaning head consists of a primary cylindrical chamber flanked by two secondary cylindrical chambers of substantially smaller diameter, the wire passing axially through the cylinders. A working fluid such as dilute alkali, water or an organic solvent is pumped into the primary cylindrical chamber via a tangentially aligned inlet, it circulates in the primary chamber, and leaves via the secondary chamber with a very high annular velocity due to the reduction in the diameter of circulation. The high circulation speed causes vibration in and around the wire in the secondary chambers with resultant abrasion of the surface of the wire. In an alternative embodiment up to all but one of the cleaning heads may be replaced by dies.