摘要:
A system and method for molding the shell of a medical device or other molded article is disclosed. The system includes a multi-axis rotational molding machine in which a mold is mounted. The mold has a cavity in the shape of the article to be molded. The mold seals to hold a vacuum. In operation, silicone or other molding material is inserted into the mold, vacuum is applied to the mold, the mold is rotated about at least two axes and a molding material coats the inside walls of the mold to form the shell or other desired article. A rotationally molded medical article is also disclosed.
摘要:
A process for forming a product having multiple and well defined color patterns. In a first embodiment, the rotomolding process comprises a first step of using a first powder having a first color and a second powder having a second color which is different than the color of the first powder. The rotomolding process comprises a second step of placing the first and second color powders into a pre-determined pattern within a hollow cavity mold. The rotomolding process comprises a third step of placing the closed hollow cavity mold into the oven. The rotomolding process comprises a fourth step of heating the hollow cavity mold with no rotation for a first period defined by the heating time necessary for a layer of individual colors to melt in the desired pattern upon the inside surface of the hollow cavity mold. The rotomolding process comprises a fifth step of rotating the hollow cavity mold in a bi-axis manner while heating the hollow cavity mold for a second period of time defined by the heating time necessary to completely melt the remaining material in the hollow cavity mold. The rotomolding process comprises a sixth step of cooling the hollow cavity mold to solidify the product. The rotomolding processes comprises a seventh step of removing the product from the hollow cavity mold. The resulting product comprises a first color pattern having the color of the first color powder and a second color pattern having the color of the second color powder.
摘要:
A rotationally cast molded article, such as a pump housing or a tank liner, is disclosed. The molded article has reinforced access openings which form flanges. The flanges are reinforced by embedded metal plates having an array of threaded metal sleeves which serve to mount the plates in the mold and which serve as threaded connectors for flanged fittings associated with the access openings.
摘要:
A mailbox combines a box body and a support molded in one piece together with working hardware, such as a handle, a door or a hinge structure for closing and opening the door of the box. The support provides multiple mounting options through a leg with an elongated segment including an expanded foot, that can be embedded in a ground surface. Alternatively, the elongated segment is truncated to expose an open end of a hollow leg. The present invention also provides a process for molding a mailbox box portion and a post portion in one piece, with the box portion including a door, a box body, and a transition sleeve connecting the door to the box body. The sleeve is truncated from the door and the box body to form an open end on the box body, and the door is pivotally mounted at the open end of said box portion. A method for rotationally molding a one-piece product with two segregated exterior color portions includes separating first and second mold chambers in a mold part by a partition wall including an access opening filled with a barrier plastic. Separated color molding material is rotationally molded in each chamber until the barrier melts during the rotational molding process.
摘要:
A method for controlling an automatic rotamolding process, the method including the steps of: metering a first prescribed quantity of plastics material powder into a hopper to be delivered to a rotatable mold as a first shot; heating the mold; when the mold reaches a prescribed temperature, delivering the first shot of powder from the hopper to the mold and simultaneously rotating the mold so as to distribute the powder over an interior surface of the mold; heating the mold in accordance with a predetermined temperature-time characteristic; cooling the mold; and ejecting the finished rotamolded product from the mold.
摘要:
A process and apparatus for internally and externally coating enclosed structures with polymeric materials are provided. In general, the process includes loading a polymeric material into the interior of an enclosed structure. The enclosed structure is then heated and rotated until a polymeric lining is formed within the structure. A second coat of polymeric material may be applied to the exterior surface of the enclosed structure while the enclosed structure is at a temperature sufficient to melt the polymeric material. The enclosed structure can include tanks, drums, barrels, pipes, and the like. In one embodiment, an apparatus having a plurality of arms is used to rotate the enclosed structures between stations corresponding to different steps in the process. The apparatus can include a cooling system for cooling the arms during operation.
摘要:
In a rotationally-molded thermoplastic refuse container of the type having a hollow handle integrally-molded with a refuse-carrying compartment of the container, the improvement which includes a wall integrally-formed with the refuse container and sealingly enclosing the hollow handle from communication with the refuse-carrying compartment of the container for providing greater strength to the container and preventing refuse from lodging in the hollow handles.
摘要:
Disclosed is a polyvinyl chloride resin powder composition for rotational molding, which is prepared by dry-blending a plasticizer and a stabilizer with a polyvinyl chloride resin followed by incorporating from 0.1 to 5 parts by weight, to 100 parts by weight of the polyvinyl chloride resin, of a finely divided polyvinyl chloride resin having a viscosity average polymerization degree of from 2000 to 5000 into the resulting dry blend. Also disclosed is a method of producing a molded article by subjecting the composition to rotational molding. The composition has good powder flowability for rotational molding, and the molded article from the composition is free from pin holes and blocks on the surface thereof.
摘要:
An apparatus for reflow smoothing a molded article made by first heating a face of a mold at a first station, then applying a fusible synthetic resin to the heated face and thereby melting the resin into a continuous coating covering the heated mold face at a second station spaced angularly from the first station, and cooling the coating and mold at the second station until the coating hardens. To reflow smooth the article, the surface of the cooled coating is then smoothed by confining the mold and hardened coating in a substantially closed chamber at the second station and reheating the confined coating until its surface flows. Thereafter the coating is cooled again at a third station angularly spaced from and downstream of the second station until it hardens and the hardened covering is stripped from the mold at a fourth station angularly spaced downstream of the third station and upstream of the first station.
摘要:
A method and apparatus for forming a product, and the product, such as a buoy with a plastic outer skin or shell and a plastic foam interior are provided. A first charge including, in one exemplary embodiment, a cross-linkable resin is added to a mold component, followed by a second charge, isolated from the first, and including in the exemplary embodiment expandable polystyrene beads. The apparatus is rotated about two mutually perpendicular axes. Initially, the cross-linkable composition is rotation molded against the walls of the mold to form the outer shell. Thereafter, the second charge of polystyrene beads is released within the mold, at a sufficient temperature to cause expansion of said beads against the shell.