Abstract: Screen deck assembly 10 has a locking system for retaining a plurality of modular screen panels 20 in such a manner that they can be individually replaced, if desired. The system includes sets of abutting retainer bars 18 which each have half of a generally cylindrical opening 28 which is adapted to receive generally cylindrical sleeve members 30. The sleeve members extend through the retainer bars and also through openings 14 in underlying support frame members 12. Locking pins 32 inserted into the sleeve members expand the lower portions of the sleeve members to lock the retainer bars relative to the support members. Sideways separation of the abutting retainer bars is prevented by downwardly extending continuous annular ring portions 72 on the sleeve members which are seated in complementary semi-circular grooves 61 formed in each of the abutting retainer bars.

Abstract: Improved flow modifier assembly for a water intake system having a cylindrical intake screen prevents damage to fish and other aquatic organisms by providing a controlled velocity profile which causes the average flow velocity to closely approach the peak flow velocity. By extending two or more concentric tubular flow modifiers into one end of the screen, it is possible to achieve flow uniformities of more than 90%, as compared to a maximum of about 72% for a prior art configuration utilizing a single tube flow modifier. In addition, the size, weight and cost of screen required can be greatly reduced for a given peak flow velocity as compared to prior art devices.

Abstract: Heat transfer tubes have an exterior surface in contact with a refrigerant and an interior surface defining a path through which a liquid is conveyed in an axial direction of the tube. The exterior surface of the tube has a plurality of fins formed thereon; the interior surface of the tube has a plurality of ridges formed thereon. The fins have an average width v with respect to the axial direction of the tube and a pitch Q with respect to the axial direction of the tube. A channel is provided between adjacent fins, the channels having a channel bottom of length L with respect to the axial direction of the tube. The ridges have a ridge height (e) and a ridge base width (b). The tubes have a ratio of L/v in a range of from 1.22 to 3.40. L is greater than 45% of fin pitch Q, and is preferably between 45% and 75% of fin pitch Q. A ratio of (e.times.L)/b is in a range of from 0.0062 to 0.0165; a ratio of e/b is in a range of from 0.565 to 0.973.

Abstract: Well screen assembly for use in horizontal wells and other situations where tensile, torsion and bending forces can damage well screens which are welded to their end supports provides a floating mounting which eliminates welding of the screen segments. A pair of complementary inner and outer slip rings are provided at one end of the well screen assembly with the inner ring being in sealed relationship with a screen segment and the outer ring being integrally affixed to an outer protective cover member and an axial support member such as a pipe base member or a tubular end fitting. The inner ring is free to slide and rotate relative to the outer ring.

Abstract: Well casing assembly for use in oil and gas wells, and especially deviated or horizontal wells, has an inner pipe member with threaded ends which permit a number of casing assemblies to be joined in a string. The inner pipe has a series of perforations along a segment of its length which are covered by an elongated screen member which prevents the passage of sand particles. A concentric outer protective cover member is devoid of perforations in regions which are radially opposite the inner screen to prevent damage to the screen. One or more perforated segments of the outer member are axially spaced from the screen member so that inward flow from a formation will have its energy and velocity reduced before it reaches the screen, thereby minimizing erosion of the screen surface. If desired, perforated flow control devices such as annular rings can be located between the inner pipe and outer member at the ends of the screen segment to allow a more uniform flow to the screen, and thus further reduce erosion.

Abstract: A compact double screen assembly (20), which can be used alone or mounted on a perforated pipe base (22), has a plurality of rods (30) arranged in cylindrical fashion around an axis (23). A wire (34) is helically wound about the rods (30) and welded thereto at every intersection. Adjacent rods (30) are separated by an inter-rod gap having a slot distance X while adjacent turns of the wire have an inter-turn slot distance Y therebetween. The rods (30) are closely spaced together such that the inter-rod slot distance X is on the order of 80-120% of the inter-turn slot distance Y, and preferably equal to it. A packing cavity (42) is provided between the rods (30) and the wire (34) for accommodating a porous media or packing material (40).

Abstract: Metallic tubes (10,10') for boiling have an outer surface (12) for contacting a refrigerant and an inner surface (14) for contacting a liquid heat transfer medium to be chilled. The outer surface (12) has a plurality of radially outwardly extending helical fins (18); the tube inner surface (14) has a plurality of helical ridges (16). The fins (18) of the outer surface are notched to provide nucleate boiling cavities having pores (30). The fins (18) and notches (N) are so spaced that the pores (30) have an average area less than 0.00009 square inches and a pore density of at least 2000 per square inch on the tube outer surface. The helical ridges (16) on the inner surface have a predetermined ridge height and pitch and are positioned at a predetermined helix angle, the inner surface having a severity factor .PHI. in the range of 0.006 to 0.008.

Abstract: Portable multi-purpose exercise device has an elongated generally tubular, and preferably cylindrical, cushion or pillow portion which is adapted to be placed behind a user's head and neck or other body portion while handle members attached to the outer ends of a stretchable cord-like tension member extending from each end of the pillow portion are engaged and pulled by the user's hands. The pillow portion preferably comprises one or more layers of resilient foam surrounding rigid sleeve members through which the tension member passes. The device is very lightweight and compact, and yet permits many exercise routines to be performed to strengthen a wide range of muscle groups. The device is especially helpful in providing head and neck support while doing ab crunches, for example.

Abstract: Lateral member assembly for use in an underdrain lateral distribution system is made of plastics but is as capable as much heavier and more costly prior art metallic assemblies in supporting a bed of filter media which must be periodically backwashed with liquid and gas. Complementary elements, including a rigid extruded floor plate member having longitudinally extending side edge channels, and an overlying screen member having flange portions adapted to be retained by undercut recesses in the side edge channels, are adapted to be assembled to each other to form hollow lateral assemblies. In a preferred embodiment, the screen member is telescopically assembled to the floor plate member to cause the screen flange portions to interlock with the recesses in the side edge channels. The resulting assembly is sealed against leakage where the members are interlocked by a pair of flexible, integral plastic sealing strips which are co-extruded with the rigid floor plate member.

Abstract: Measuring device for quickly and accurately determining the thickness of an annulus between two cylindrical members, such as the catalyst retaining screens of a radial flow reactor, at any point along its length or circumference, comprises a wheeled cart having two sets of angularly mounted wheels which straddle the inner screen and a pair of spring loaded plungers with ball shaped contacts which contact the outer screen. As the device is lowered into an annulus with a cable, a pair of ultrasonic transducers positioned inside the cart direct opposed beams radially of the annulus to permit the radial distance between the screens to be measured.

Abstract: Underdrain lateral system, which is especially adapted for use in a gravity filter bed, includes, as its preferred embodiment, scallop-shaped laterals having an upper, wrapped wire, slotted screen surface. The screen surface supports and retains the filter media particles directly, without the necessity of an underlying gravel layer, and is itself supported by channel-shaped rod members which are welded to the wires. The web portions of the channel rods perform the function of simultaneously distributing air and water during backwashing, and include small apertures in upper channels and larger apertures in lower channels to cause a plenum to be formed inside the laterals which ensures that the distribution of air and water will be uniform throughout the lateral, even if the lateral is not perfectly level.

Abstract: An underdrain assembly for a bed of filter media includes a plurality of elongated screen lateral elements which each have a generally flat bottom surface and a convexly curved upper surface which has flow openings therein. The lateral elements each have a width substantially greater than their height and include a means defining a generally tubular-shaped surface positioned internally thereof. The generally tubular-shaped surface includes flow distribution openings which have a total open area less than the total area of the flow openings in the curved upper surfaces of the lateral elements. In various embodiments, the generally tubular-shaped surfaces are shown as comprising a single tube, a plurality of tubes, and a tube defined by the portions of a plurality of adjacent channel-shaped members whose leg portions support the curved upper surface of the screen lateral elements.

Abstract: An elongated screen assembly, which in various forms, is useful as a scallop in a reactor, or as an underdrain for a gravity filter system, has a cross-section in a direction normal to its axis which is at least twice as wide as it is high. A method is also disclosed for manufacturing the screen assembly by pressing the opposed sides of a wrapped wire cylindrical screen assembly between a pair of plates which have radii of curvature which are different from each other and greater than the radius of curvature of the cylindrical screen assembly.

Abstract: Mounting system for substantially increasing the wear life of a screen panel which is adapted to be vibrated, utilizes elastomeric material, such as urethane, to isolate the vibrating mechanism from direct contact with the screen panel. An elastomeric wear strip is bonded to screen wires on the underside of the screen panel. A recessed channel formed in the bottom of the wear strip is adapted to engage an upper contact surface of a rigid vibrating bar member, while the side edges of the channel extend downwardly over the sides of the rigid vibrating bar member to prevent abrasive material which has passed through slots in the screen panel from entering the contact area between the recessed channel and the upper contact surface. The upper contact surface of the vibrating bar member is preferably covered with elastomeric material and crowned so as to cause the screen panel to become curved when its side edges are forced down by a pair of hold-down bars.

Abstract: Improved method and apparatus for making finned tubing from difficult to work materials such as titanium and stainless steel uses spaced sets of finning discs on a plurality of arbors to form a tube against a mandrel having different diameters under each set of discs. By forming the tube fin tips to their final O.D. in a first disc set and by deepening their roots to bring the fins to their final height in a second disc set, tubes with higher fin counts and/or higher fin heights can be achieved than were formerly possible. The process of separately cold working the tips and roots also permits tubes to be made which are dimensionally identical to prior art tubes but with higher quality and productivity since tube stresses are greatly reduced. An improved titanium tube is also disclosed which has at leasts 26 fins per inch, a fin height of at least 0.034" and an outside to inside surface area ratrio of at least 3.0.

Abstract: The invention relates to conventional metal well screens which have a screen wire wrapped about a plurality of internal support rods to define the screen slots, and particularly to a novel plastic end fitting made of a thermoplastic material which is mechanically attached to the well screen by means of a plurality of circumferentially spaced tongues which engage the inside surface of the screen wires and have a portion of their outer surface positioned within the screen slots. Slots formed in the end fitting between the tongue portions contain the support rods. A method of attaching a thermoplastic fitting made of a material such as polypropylene is also disclosed and includes the steps of heating the tongue portions so that a portion of their outer surface is melted and then is forced radially outwardly into the screen slots, and preferably slightly beyond them, by a pressure applying device such as a tapered wedge tooling arrangement.

Abstract: A food service tray, preferably formed of molded plastic, is particularly adapted to be used in a service cart which can heat food contained in a predetermined "hot" area of the tray. The tray has a generally flat planar portion from which the side walls of at least one dish-shaped recess extend both upwardly and downwardly. The said at least one dish-shaped recess preferably contains a disposable insert dish and has a bottom surface which is thinner than other portions of the tray in order to facilitate the transfer of heat to food contained in the dish. Integral ribs formed on the lower outer side walls of the recess serve to resiliently and frictionally engage the dish's cover after it has been removed and inverted. In the inverted position, the cover insulates the hot bottom of the tray during serving. The tray preferably also includes a second downwardly recessed portion for cold food, cups and utensils.

Abstract: The invention relates to a novel tubular fitting member formed of a deformable material, such as steel, which may be combined with a helically wrapped wire screen to produce a mechanical seal of a gap formed adjacent the cut-off end portion of the screen when the screen is cut off perpendicular to its supports. Such cutting produces a loose, tapered wire tail which is normally broken off, thereby producing an open gap in the screen which is wider than the width of the slot between the wire wraps. The tubular fitting member has a groove formed in its outer surface closely adjacent to the screen end of the fitting. The groove defines the inner wall of a deformable flange which may be selectively forced toward the screen to close any gap formed adjacent its end during the cut-off operation.

Abstract: Improved heat transfer tube and method of making same has mechanical enhancements which can individually improve either the inner or outer surfaces or which can cooperate to increase the overall efficiency of the tube. The internal enhancement, which is useful on either boiling or condensing tubes, comprises a plurality of closely spaced helical ridges which provide increased surface area and are positioned at an angle which gives them a tendency to swirl the liquid. The external enhancement, which is applicable to boiling tubes, is provided by successive cross-grooving and rolling operations performed after finning. The finning operation, in a preferred embodiment for nucleate boiling, produces fins while the cross-grooving and rolling operation deforms the tips of the fins and causes the surface of the tube to have the general appearance of a grid of generally rectangular flattened blocks which are wider than the fins and separated by narrow openings between the fins and narrow grooves normal thereto.

Abstract: Plural pipe-based well screen segments can be assembled more quickly and easily and with no chance of damage to the screen jacket by welding a boss ring to the center pipe of each segment intermediate the upper pipe end and the screen jacket and then using a slip to support the boss ring. The slip is designed to be supported by holes normally present in the master bushing of a rotary drilling table or platform and is of sufficient height that the screen sections can be joined without the operator having to bend over. A pair of relatively light weight, hinged cantilevered plates can be easily lifted to provide clearance for the screen jacket to be lowered through the table and are then moved to their horizontal position just before the boss ring portion of the screen is lowered so as to engage them. A vertical bar on the slip acts as a wrench stop to permit the upper end of the pipe to be held stationary as the succeeding segment of screen is threaded to it.