It has been suggested that Hot Gas Welding be merged into this article. This article needs additional citations for verification. Welding of thermoplastics is accomplished in three sequential stages, namely surface preparation, application hot Plastic PDF heat and pressure, and cooling.
Le jeune Kevin a perdu sa mère à douze ans et vie avec son père Jerry, escroc professionnel. L’éducation paternelle peu orthodoxe ayant porté ses fruits, Kevin est vite passé maître dans l’art d’abuser d’autrui. C’est ainsi que le duo va de ville en ville, de motel douteux e, chambre miteuse, toujours en quête du gros coup. Colette veut à tout prix gravir les échelons qui lui permettront d’accéder à ses rêves de grandeur sophistiquée et, malgré sa jeunesse, c’est déjà une arnaqueuse aussi douée que redoutable. Elle devient bientôt la complice et l’amante de Jerry. Derrière une façade classique – le trio en quête de l’ultime arnaque – Peter Craig crée un univers romanesque trouble qui n’est pas sans évoquer celui de Jim Thompson. Si Hot Plastic peut se lire comme un hommage aux histoires d’escroquerie, c’est aussi une œuvre personnelle qui explore les liens familiaux et les relations amoureuses dans l’Amérique contemporaine.
Classification of welding methods for semi-finished polymeric materials. Production of a good quality weld does not only depend on the welding methods, but also weldability of base materials. Hot gas welding, also known as hot air welding, is a plastic welding technique using heat. A specially designed heat gun, called a hot air welder, produces a jet of hot air that softens both the parts to be joined and a plastic filler rod, all of which must be of the same or a very similar plastic. Welding PVC to acrylic is an exception to this rule. In the case of webs and films a filler rod may not be used.
This is a quick welding process and can be performed continuously. A plastic welding rod, also known as a thermoplastic welding rod, is a rod with circular or triangular cross-section used to bind two pieces of plastic together. They are available in a wide range of colors to match the base material’s color. Spooled plastic welding rod is known as « spline ». An important aspect of plastic welding rod design and manufacture is the porosity of the material.
The highest quality of plastic welding rods are therefore those with zero porosity, which are called voidless. Heat sealing is the process of sealing one thermoplastic to another similar thermoplastic using heat and pressure. The direct contact method of heat sealing utilizes a constantly heated die or sealing bar to apply heat to a specific contact area or path to seal or weld the thermoplastics together. Heat sealing is used for many applications, including heat seal connectors, thermally activated adhesives and film or foil sealing. As the rod softens, it is pushed into the joint and fuses to the parts. This process is slower than most others, but it can be used in almost any situation. With speed welding, the plastic welder, similar to a soldering iron in appearance and wattage, is fitted with a feed tube for the plastic weld rod.
The speed tip heats the rod and the substrate, while at the same time it presses the molten weld rod into position. A bead of softened plastic is laid into the joint, and the parts and weld rod fuse. Extrusion welding allows the application of bigger welds in a single weld pass. It is the preferred technique for joining material over 6 mm thick.
Welding rod is drawn into a miniature hand held plastic extruder, plasticized, and forced out of the extruder against the parts being joined, which are softened with a jet of hot air to allow bonding to take place. This is the same as spot welding except that heat is supplied with thermal conduction of the pincher tips instead of electrical conduction. Two plastic parts are brought together where heated tips pinch them, melting and joining the parts in the process. Related to contact welding, this technique is used to weld larger parts, or parts that have a complex weld joint geometry. The two parts to be welded are placed in the tooling attached to the two opposing platens of a press. A hot plate, with a shape that matches the weld joint geometry of the parts to be welded, is moved in position between the two parts. Hot-plate welding equipment is typically controlled pneumatically, hydraulically, or electrically with servo motors.