Abstract: Welding apparatus for plastic lining (5) in concrete tubing (4) comprises a centering carriage (6) movable inside the tubing along its length and fixable in position at a location adjacent a butt joint (51) having a seam to be welded. A carrier arm (10) is mounted for rotation about an axis (9) coincident with the axis of the tubing (4) for supporting a welding unit (14) at its outer end remote from the axis of the tubing. A drive source (15, 16) adjacent the welding unit engages the interior of the tubing and self propells the welding unit (14) and carrier arm (10) around the interior of the tubing (4). The welding unit (14) is biased outwardly towards the wall of the tubing and is guided along the welding seam by either a guide ring (21) or a roller (20) engaging a gap (48) between adjacent tubing sections. Several degrees of freedom are provided for accommodating lack of concentricity and translation of the welding unit along the length of the tubing without moving the centering carriage.

Abstract: A filament-reinforced plastic article has a fluid-impermeable wall with a relatively low surface resistivity to prevent buildup of dangerous electrostatic charge. The article includes overlapping bands of filaments coated with plastic. A minor portion of the filaments in at least some of the bands is electrically conductive so that electrically conductive filaments are distributed throughout the wall.

Abstract: Resin-coated filaments wound around a mandrel to make a plastic pipe or fittings. In making a fitting with a nonlinear axis, the mandrel is supported with one end adjacent a winding station and rotated about an axis substantially tangent to the nonlinear axis at the winding station. The rotating mandrel oscillates back and forth past the winding station while maintaining the nonlinear axis substantially tangent to the axis of rotation. Resin-coated filaments pass between longitudinally spaced and curved guide fingers and are wrapped around the rotating mandrel in overlapping helical patterns as it moves back and forth past the winding station. The mandrel is removed from the fitting after the resin has cured.

Abstract: A solution containing hydrolyzed organotin siloxane polymeric material is formed by hydrolyzing an organotin R-oxy siloxane in a water miscible solvent; R being an alkyl or alkoxyalkyl group with less than six carbon atoms. A water immiscible solvent is added and the water miscible solvent and R-alcohol from hydrolysis are removed by distillation. A marine antifouling coating can be made when the water immiscible solvent evaporates from the solution. A preferred embodiment hydrolyzes tributyltin ethoxysiloxane in ethyl alcohol with xylene as the water immiscible solvent.

Abstract: Plastic pipe is continually produced from a curable resin on a plurality of horizontal mandrels which are repeatedly simultaneously moved between plastic pipe production stations. There is at least one station for applying resin to a mandrel, at least one station for curing resin on the surface of a mandrel, and at least one pipe removal station for removing pipe from a mandrel. The pipe stations are substantially radially equidistant from a central horizontal axis and are circumferentially spaced apart by substantially equal increments around the horizontal axis. Each mandrel is progressively rotated between the stations.The temperature of each mandrel is controlled by passing a fluid through the mandrel. Heating fluid passes through mandrels in resin cure stations and cooling fluid passes through mandrels in resin application and pipe removal stations. A control system minimizes mixing of the cooling and heating temperature control fluids when the mandrel is rotated between stations.

Abstract: Compositions for protecting materials from growth of pestiferous organisms, and particularly for protecting marine surfaces from fouling organisms, are formed from precursors having the formula ##STR1## where m is from 1 to about 10, where each X is independently selected from the group consisting of alkyl and alkoxyalkyl radicals containing less than about 6 carbon atoms and Y, where Y has the formula ##STR2## where R.sub.1 R.sub.2 and R.sub.3 are independently selected from the group consisting of alkyl, cycloalkyl, and aryl radicals, where R.sub.1, R.sub.2 and R.sub.3 contain in combination up to about 18 carbon atoms. The ratio of the tin atoms to silicon atoms in the precursors is at least about 1:50.The precursors can be directly used as an additive for coatings. The precursors can also be used by subjecting them to hydrolysis and polycondensation to form an organotin substituted polysiloxane for use as an additive and a binder for coatings.

Abstract: An insulated pipe for conducting high and low temperature fluids includes a rigid carrier pipe, a layer of volumetrically compressible insulating material around the O.D. of the carrier pipe, and a protective outer pipe around the insulating layer. The method of making the pipe product includes placing a closed flexible bag around the carrier pipe and the insulating layer, and then drawing a vacuum on the interior of the bag to compress the insulating layer. The outer pipe is slid lengthwise over the compressed insulating layer, and the vacuum is then removed to allow the insulation to partially expand and fill the annulus between the carrier pipe and the outer pipe.

Abstract: Polyurethane resins are prepared by reacting a high solids polyol-containing component with an isocyanate-containing component. The polyol-containing component comprises the transesterification product of from about 70 to about 90 parts by weight castor oil and from about 5 to about 20 parts by weight pentaerythritol, where the solids content of the polyol-containing component is at least about 60% by weight. Preferably, the polyol-containing component also comprises from about 5 to about 30 parts by weight of a condensation agent having a molecular weight of less than about 400 and selected from the group consisting of polycarboxylic acids having up to about 4 carboxyl groups, methyl and ethyl esters of such polycarboxylic acids, and combinations thereof.

Abstract: Compositions for protecting materials from growth of pestiferous organisms, and particularly for protecting marine surfaces from fouling organisms, are formed from precursors having the formula ##STR1## where m is from 1 to about 10, where each X is independently selected from the group consisting of alkyl and alkoxyalkyl radicals containing less than about 6 carbon atoms and Y, where Y has the formula ##STR2## where R.sub.1, R.sub.2 and R.sub.3 are independently selected from the group consisting of alkyl, cycloalkyl, and aryl radicals, where R.sub.1, R.sub.2 and R.sub.3 contain in combination up to about 18 carbon atoms. The ratio of the tin atoms to silicon atoms in the precursors is at least about 1:50.The precursors can be directly used as an additive for coatings. The precursors can also be used by subjecting them to hydrolysis and polycondensation to form an organotin substituted polysiloxane for use as an additive and a binder for coatings.

Abstract: Plastic pipe reinforced with rovings is produced by wetting the rovings with liquid resin and winding the wetted rovings onto a rotating mandrel from a carriage that moves to and fro along the length of the mandrel. The rovings are drawn onto the mandrel over a concavely arched surface mounted on the carriage. As the carriage reverses its direction at each end of the mandrel, the tilt of the concavely arched surface with respect to the carriage also reverses so the rovings always pass over the same section of the concavely arched surface. Apparatus for practicing this process is described.

Abstract: Polymeric structures having interpenetrating matrices in cured form comprising an epoxy-polyamine network and a polysiloxane network. The interpenetrating network physical and chemical properties are improved over those of either polymeric component alone. The network can be prepared by simultaneously reacting epoxy resin having at least two oxirane groups with amine curing agent, and having present at least 0.1 equivalent of silane, water being substantially uniformly distributed throughout the mixture in an amount sufficient to bring about substantial hydrolytic polycondensation of the silane to form a cross-linked interpenetrating polymer network. The amine curing agent may be substituted wholly or in part by aminosilane. Sources of silane may include aminosilane and epoxysilane. Relative reaction rates of formation of the polymeric networks are controlled, to get good intertwining of the two polymers.

Abstract: Epoxy resins are cured with an amine adduct of orthohydroxybenzoic acid of the formula: ##STR1## where x is from 2 to about 8.

Abstract: Compositions for protecting materials from growth of postiferous organisms, and particularly for protecting marine surfaces from fouling organisms, are formed from precursors having the formula ##STR1## where m is from 1 to about 10, where each X is independently selected from the group consisting of alkyl and alkoxyalkyl radicals containing less than about 6 carbon atoms and Y, where Y has the formula ##STR2## where R.sub.1, R.sub.2 and R.sub.3 are independently selected from the group consisting of alkyl, cycloalkyl, and aryl radicals, where R.sub.1, R.sub.2 and R.sub.3 contain in combination up to about 18 carbon atoms. The ratio of the tin atoms to silicon atoms in the precursors is at least about 1:50.The precursors can be directly used as an additive for coatings. The precursors can also be used by subjecting them to hydrolysis and polycondensation to form an organotin substituted polysiloxane for use as an additive and a binder for coatings.

Abstract: A moving, fibrous web is impregnated with a liquid by placing the liquid on the surface of the web, spreading the liquid over the web surface, pressuring a portion of the liquid into the web to partially saturate the web with the liquid and leave residual liquid on the web, and metering the residual liquid into a layer of substantially uniform thickness. This layer is then forced into the web to saturate it with liquid. This method is particularly effective for producing plastic pipe incorporating at least one layer of fibrous material saturated with liquid resin .Apparatus for practicing this method comprises a first surface transverse to the surface of the web, and a second surface converging with the web in the direction of travel of the web. The first surface performs the spreading step and the second surface performs the pressuring and metering steps.

Abstract: Reinforced plastic pipe is made at high rates using a wiper to remove resin from the surface of the rovings after they are applied to a rotating mandrel. The wiper leaves an optimum surface layer of resin on the rovings. For small diameter pipe, production rates are further increased by rotating the mandrel above its first critical speed.

Abstract: Apparatus for applying tension to a wire rod while wrapping the rod on a pipe for prestressing the pipe. The tension device includes a frame movable lengthwise of the pipe, the frame having a shaft parallel to the pipe on which is rotatably mounted a bull wheel around which a single turn of the wire rod is wrapped. A hydraulic pump is supported on a torque frame which in turn is rotatably supported on the shaft. The pump is driven in response to rotation of the bull wheel. A load-sensing element is mounted on the frame and engages the torque frame at a radial distance from the axis of the shaft that is substantially equal to the radius of the bull wheel. The hydraulic load on the pump controls the torque load on the bull wheel and hence the tension in the rod as it is withdrawn tangentially from the bull wheel. The reaction torque on the torque frame is measured by the load sensing element, the sensing element thus giving a direct measure of rod tension.

Abstract: Plastic pipe is removed from a mandrel by forming two circumferential grooves of different depth in the pipe wall, attaching a holding means to the pipe where the holding means has projections which fit into the grooves, and then applying an axial force to the holder. This method prevents damage to the mandrel and the pipe.

Abstract: Room temperature curable epoxy compositions and method are disclosed. The compositions comprise resinous epoxide; a mixed amine-ketimine curing agent comprising a cyclic polyamine having at least two epoxide-reactive, aliphatic amino functional groups, a portion of the amino functional groups in the mixed curing agent being in ketimine form the remainder being in the free amine form; and water in at least about the stoichiometric proportion for hydrolyzing the ketimine groups to the free amine form. The compositions may also comprise inorganic filler such as finely divided silica and sand. The ingredients of the composition are mixed to form a sprayable composition.

Abstract: A quick disconnect coupler in which a plurality of jaw clamping units are supported around the periphery of a pipe section for clamping the flange of a second pipe section in engagement with the first pipe section. Each hydraulic unit includes a support member secured to the outer periphery of the pipe and a frame member slidably supported on the support member for sliding movement parallel to the axis of the pipe. An overcenter toggle linkage connects a jaw member to the frame member. A rotatable cam pivotally secured to the frame member engages a stop on the support member. One end of a hydraulic actuator is connected to the cam for rotating the cam while the other end is connected to the toggle linkage for moving the jaw. The actuator causes the toggle linkage to move the jaw into clamping engagement with the flange of the second pipe, while the other end of the hydraulic actuator rotates the cam whem the toggle linkage reaches the overcenter locked position.

Abstract: Compositions for protecting materials from growth of pestiferous organisms, and particularly for protecting marine surfaces from fouling organisms, are formed from precursors having the formula ##STR1## where m is from 1 to about 10, where each X is independently selected from the group consisting of alkyl and alkoxyalkyl radicals containing less than about 6 carbon atoms and Y, where Y has the formula ##STR2## where R.sub.1, R.sub.2 and R.sub.3 are independently selected from the group consisting of alkyl, cycloalkyl, and aryl radicals, where R.sub.1, R.sub.2 and R.sub.3 contain in combination up to about 18 carbon atoms. The ratio of the tin atoms to silicon atoms in the precursors is at least about 1:50. The precursors can be directly used as an additive for coatings. The precursors can also be used by subjecting them to hydrolysis and polycondensation to form an organotin substituted polysiloxane for use as an additive and a binder for coatings.