Abstract: This continuous galvanizing method and apparatus passes a linear element to be galvanized, e.g., wire, rod, or tube, through a surrounding, relatively short length of conduit which is attached as a cross-tee to the end of a delivery pipe rising from a centrifugal pump submerged in a vat of molten zinc, and continuously flooded with liquid zinc to coat the linear element. The zinc flowing from the open ends of the conduit, and falling as excess from the element being coated, drops back into the vat for recirculation. The vat is covered to provide a substantially closed operating space above the pool of molten zinc to enable the coating to take place in an inert atmosphere.

Abstract: A method of galvanizing ferrous linear elements, e.g., tube, pipe, structural shapes, as part of a continuous manufacturing line by passing the axially travelling preheated element through transversely flowing molten zinc.

Abstract: A method and apparatus for applying a coating to a continuous length of tubing. A coating chamber having entry and exit ports substantially encloses a portion of the tubing while permitting the tubing to pass continuously therethrough. Airflow into the coating chamber through the exit port strips excess coating material from the tubing surface. Air is withdrawn from the coating chamber by vacuum pumps through one or more separation chambers which separate entrained particles or droplets of coating material from the air. The coating chamber is preferably disposed at a distance from the separation chamber(s). The vacuum line connecting the coating chamber with the separation chamber(s) is preferably flexible or breakable. The separation chambers are preferably capable of being operated in series or in parallel. Adjustable masks are preferably provided at the entry and exit ports of the coating chamber. A seal is preferably provided at the entry port.

Abstract: A hinged connector for joining a first structural member to a second structural member in a support structure, comprising first and second metal connector members each having a base portion for attachment to a respective structural member and a tab integral with the base portion. Each base portion includes an integral upset gusset welded to the tab of the respective connector member to add support to the tab and add stiffness to the connector member.

Abstract: A method and apparatus for continuous galvanizing of a linear element wherein controlled flow of molten zinc onto the linear element is effected through one or more nozzles, whereby galvanizing may be accomplished without immersion of the linear element in molten zinc. In a preferred embodiment, the apparatus of the invention comprises an annular nozzle having a central opening through which the linear element is axially advanced. The nozzle is configured to provide a converging, generally frustoconical curtain of molten zinc flowing continuously onto the exterior surface of the linear element.

Abstract: A plastic-lined metallic pipe including an outer metallic pipe which supports an inner plastic sleeve with mechanical engagement between the plastic sleeve and the metallic pipe throughout the circumference of the sleeve. The metallic pipe has a longitudinal weld and the plastic sleeve is melt-bonded to the metallic pipe along the weld only.

Abstract: An improved method of manufacturing galvanized steel tubing from steel strip having at least one galvanized surface, which surface becomes the exterior surface of the tubing is provided. In the method of the invention, after the steel strip is roll-formed and welded to complete the tubing and the welded seam is scarfed to remove irregularities, a quantity of an acid solution is applied to substantially only the scarfed area to react with oxidized metal, and the rinsed, leaving the non-scarfed galvanized exterior surface intact. The tubing is then heated to a temperature sufficient to cause the galvanized coating of the exterior surface to begin to flow and the tubing is regalvanized to produce an improved galvanized exterior surface, which is resistant to cracking along the scarfed area.

Abstract: Apparatus for continuously manufacturing plastic-lined metallic pipe. The apparatus includes an extruder having an output providing a plastic sleeve and further includes a continuous roll-forming tubing mill production line. This production line includes a series of forming rolls which progressively deform a substantially flat steel strip to a generally tubular configuration as the strip move along a straight-line longitudinal path. The production line further includes an electrical resistance or high frequency welder which continuously welds the lateral edges of the moving strip to complete the pipe. The apparatus also includes a feed for the plastic sleeve into the incipient metal pipe upstream of the welder. The plastic sleeve has an outside diameter slightly smaller than the inside diameter of the metallic pipe in its as-formed condition.

Abstract: An improved method of manufacturing galvanized steel tubing from steel strip having at least one galvanized surface, which surface becomes the exterior surface of the tubing is provided. In the method of the invention, after the steel strip is roll-formed and welded to complete the tubing and the welded seam is scarfed to remove irregularities, a quantity of an acid solution is applied to substantially only the scarfed area to react with oxidized metal, and then rinsed, leaving the non-scarfed galvanized exterior surface intact. The tubing is then heated to a temperature sufficient to cause the galvanized coating of the exterior surface to begin to flow and the tubing is regalvanized to produce an improved galvanized exterior surface, which is resistant to cracking along the scarfed area.

Abstract: Method for continuously manufacturing plastic-lined metallic pipe. The method includes an extruder having an output providing a plastic sleeve and further includes a continuous roll-forming tubing mill production line. This production line includes a series of forming rolls which progressively deform a substantially flat steel strip to a generally tubular configuration as the strip moves along a straight-line longitudinal path. The production line further includes an electrical resistance or high frequency welder which continuously welds the lateral edges of the moving strip to complete the pipe. The method also includes a feed for the plastic sleeve into the incipient metal pipe upstream of the welder. The plastic sleeve has an outside diameter slightly smaller than the inside diameter of the metallic pipe in its as-formed condition. Furthermore, the plastic sleeve maintains a generally tubular configuration from the time it enters the pipe until the manufacture of the plastic-lined pipe is completed.

Abstract: A conduit coupling assembly for connecting the end portions of a pair of lengths of conduit in coaxial relationship. The end portions of the lengths have external threads of the same size. The coupling assembly includes an annular outer coupling member and an annular inner coupling member for reception by the outer coupling member. The outer coupling member has a first end including an internal screw thread sized for threading onto the end portion of one of the conduits. This outer member also includes a second end including an outer wall defining a cavity with the outer wall having at least one threaded aperture therethrough opening onto the cavity. The inner coupling member includes a first end and an internal screw thread sized for threading onto the end portion of the other of the conduits.

Abstract: A modular barrier comprising a pair of vertical posts, a pair of parallel rails and a holding assembly for retaining the ends of the rails inside the posts. Each of the posts has a facing vertical wall with the vertical wall having an upper window and a lower window. An upper tongue extends upwardly into the upper window while a dependent lower tongue extends into the lower window. Each of the rails has a first end disposed inside one of the posts and a second end disposed inside the other post. The posts have facing inside walls and each of the walls has an indentation adjacent the rails receiving a corresponding one of the tongues. The holding assembly is positioned entirely within a post and functions to push the rails towards each other so that the tongues are held in their corresponding indentations to maintain the posts and rails assembled.

Abstract: A metallic wall having coined knockouts. The wall includes a first surface and a second surface spaced from the first surface. A plurality of spaced knockout portions are positioned in incipient apertures in the wall and are disposed substantially between the surfaces. Each knockout portion is defined by a first indentation encompassing the knockout portion and extending from the first surface, and by a second indentation encompassing the knockout portion and extending form the second surface. These indentations are in alignment with a web of material of substantially uniform thickness throughout its length spacing the indentations. The outside surface defining the first indentation is inclined inwardly. A coating is applied to the second surface after formation of the indentations. A sharp blow to the knockout portion from the second surface fractures the web to allow removal of the knockout portion without any material of the wall extending substantially beyond the first surface.

Abstract: A connector assembly for joining a horizontal member and a vertical member without the formation of substantial exposed gaps. The assembly includes a base with a saddle surface at one end and an abutment flange at the other end. The base has an aperture between the ends and a slot communicating with the aperture. A locking collar has a bore receiving the base and an inwardly directed annular lip at a first end of the collar. The collar also includes an internal screw thread and an abutment for engaging the flange of the base. Also the assembly includes a locking insert with a body for reception in the base. The insert has extending arms at one end terminating in screw threads and at the other end a holding flange for retaining the horizontal member. A method of using the connector assembly is also disclosed.

Abstract: A method for making endless lengths of nylon coated metal tubing which coating has high mechanical strength characteristics and a low gloss surface finish. The method includes passing the formed tubing through a first powder coating region and applying a layer of nylon generally uniformly surrounding the circumference of the tubing. This first nylon powder coating is heated sufficiently to cause the nylon coating to achieve complete melt-flow into a continuous first nylon coating region which would have a relatively high gloss. The coated tubing is next passed through a second powder coating region with the surface temperature of the first coating still above the melting temperature of the nylon. At this second coating region a second powder coating of the same type of nylon is applied. The second coating is cooled below the melting point of the nylon before the second coating completely melts leaving the outer surface with a very low gloss surface finish.

Abstract: An improvement in a continuous rolling mill for forming flat steel strip into tubing. The improvement is a strip preparation station including upper and lower composite roller systems. Each system has end rollers which define a pass path for the strip. The lower end rollers have a support surface for engaging the lower surface of the strip and an outer pocket with a lower transition surface extending between the support surface and the outer pocket. Each of the upper end rollers has an engagement surface for contacting the upper strip surface and an outer flange which terminates below the level of the support surface and extends into the pocket. Each upper end roller has a bevelled working surface adjoining the engagement surface and overlying at least a portion of the transition surface and a portion of the support surface for cold working the irregularities of the strip. A method of preparing a strip for formation into a tube in a continuous rolling mill is also disclosed.

Abstract: An in-line, continuous, roll-forming tube mill production line. The line includes a supply station for continuously supplying steel strip, a roll-forming station for forming the strip into a tubular configuration, and a welding station for joining by welding the edges of the strip. The line also has at least one station for performing a process which calls for the application of a liquid to the exterior of the tubing such as cleaning, rinsing or applying a coating. A preheating station is provided for preheating of the tubing by induction and a powder coating station applies a plastic coating or a metallically pigmented plastic coating to the exterior of the tubing, the powder coating station having a chamber and means for selectively isolating the tubing from chamber. Finally, the tube mill production line includes a heating station for baking and/or curing of the powder coating.

Abstract: An elongated wall formed substantially of metallic material. The wall includes a first surface and a second surface spaced from the first surface. A plurality of spaced knockout portions are disposed in incipient apertures extending through the wall and these knockout portions are adapted to be selectively removed from the remainder of the wall by application of force to the portion to be removed. This force could be applied as by subjecting the knockout to a sharp blow directed to the portion. Each knockout portion so completely fills its corresponding aperture as to render the wall substantially impervious to the passage of fluid. The wall further comprises a coating applied to one of its surfaces. A method of forming the wall is also disclosed.

Abstract: An impeder for use in a mill for roll-forming tubing. The mill includes a feed station for supplying an elongated steel strip in flat form and a station where the strip is transversely bent from its planar condition causing the lateral edges of the strip to be brought together in abutting relationship. An induction coil is positioned about the bent portion of the strip for inducing current flow through the location where the lateral edges first abut to heat the lateral edges to plasticity. The mill also includes a weld rolls station where the plastisized lateral edges are firmly pushed together to complete welding of the tube. The impeder is disposed inside the induction coil adjacent the location where the lateral strip edges are first brought into abutting relationship. The impeder includes an outer shell made of a strong, heat-resistant material, a core disposed inside a shell and formed by an aggregation of ferromagnetic material, and components for causing passage of a coolant through the core material.

Abstract: A tubing mill for roll forming a strip of metal into a fluted tube having alternating longitudinally extending high and low portions on its outside surface. The mill includes feed means for supplying a generally planar strip of metal and embossing means for forming the high and low portions on the surface of the strip to be formed into the outside surface of the tube. The mill also includes breakdown means for sequentially transversely bending the strip from its planar condition. The breakdown means includes roller means having a gripping surface for engaging the strip and having alternating high and low portions shaped to mate with those of the strip. Additionally, the mill includes closure means for bringing into abutment the lateral ends of the bent portions of the strip, and welding means for seam welding the ends together.