摘要:
Process for manufacturing a plastic fuel tank (FT) equipped with an internal accessory, by moulding a parison using a mould comprising two cavities and a core, said process comprising the following steps : 1. the parison is introduced into the mould cavities; 2. the core is introduced inside the parison, said core having first been fitted with the accessory; 3. the mould is closed so that the cavities come into leaktight contact with the core; 4. the parison is pressed against the cavities by blowing through the core and/or applying a vacuum behind the cavities; 5. the accessory is fastened to the parison by snap riveting using a device attached to the core; 6. the mould is opened to withdraw the core; and 7. the final moulding of the parison is carried out by blow moulding (by injecting a pressurized fluid inside the parison) and/or thermoforming (by applying a vacuum behind the cavities), in which the accessory comprises an orifice for the snap riveting (5) and at least one protuberance, for which the constituent material, the dimensions and the position are such that during the fastening of the accessory by snap riveting, this protuberance will at least partially melt to form a local weld which is at another location than the obtained rivet so as to obtain two different attachment points.
摘要:
A laser-welded article comprises: a laser-transmissible workpiece made from a laser-transmissible colored resin composition including at least a thermoplastic resin and an alkaline earth metal salt of an anthraquinone-type acidic dye represented by the following chemical formulae (1) and/or (2) and a laser-absorptive workpiece putting the laser-transmissible workpiece together,
wherein the workpieces are welded at the put position thereof by irradiated laser towards the laser-transmissible workpiece that transmits therethrough and is absorbed into the laser-absorptive workpiece.
摘要:
Large fittings or other structures are made by rotationally moulding a first component 18 of polyethylene and joining cylindrical pups 20, 22, 24 of polyethylene to the component by butt fusion joints 26, 28, 30. The structure within the boundary 50 is irradiated with gamma radiation followed by post-heating to remove free radicals. The extremities of the pups are shielded to prevent irradiation. Their capability to be joined to polyethylene pipes 12, 14, 16 by butt-fusion joints 32, 34, 36 is unimpaired. The irradiation introduces cross-linking to give improved properties such as impact resistance and stress crack resistance and to bring the fitting within the specification for polyethylene pipe for natural gas distribution. The joints 26, 28, 30 are made using differential heating of the ends to be joined to compensate for differences in melt flow index. Alternatively, the component 18 is slightly irradiated to lower its MFI before pups are joined to it.
摘要:
A laser-welded article comprises: a laser-transmissible workpiece made from a laser-transmissible colored resin composition including at least a thermoplastic resin and an alkaline earth metal salt of an anthraquinone-type acidic dye represented by the following chemical formulae (1) and/or (2) and a laser-absorptive workpiece putting the laser-transmissible workpiece together, wherein the workpieces are welded at the put position thereof by irradiated laser towards the laser-transmissible workpiece that transmits therethrough and is absorbed into the laser-absorptive workpiece.
摘要:
A laser-welded article comprises: a laser-transmissible workpiece made from a laser-transmissible colored resin composition including at least a thermoplastic resin and an alkaline earth metal salt of an anthraquinone-type acidic dye represented by the following chemical formulae (1) and/or (2) and a laser-absorptive workpiece putting the laser-transmissible workpiece together, wherein the workpieces are welded at the put position thereof by irradiated laser towards the laser-transmissible workpiece that transmits therethrough and is absorbed into the laser-absorptive workpiece.
摘要:
Process for manufacturing cellular structure based on a composition comprising an amorphous thermoplastic polymer and made up of sheets extruded in parallel and intermittently welded, according to which: - an amorphous polymer composition is chosen which has a dynamic melt viscosity, measured at its processing temperature and at an angular velocity of 0.1 rad/s, of less than 2000 Pa.s; and - the temperature of the coolant is regulated so that it is at least equal to Tg - 20°C, where Tg is the glass transition temperature of the composition based on the amorphous polymer.
摘要:
A method of fabricating a thermosetting matrix, fiber reinforced composite structure (12) wherein a stack of fiber reinforced thermosetting plies (10,14,16,) are assembled; an ultrasonic horn (30) is engaged with a top surface of the upper most ply, oriented at an acute angle with respect to the top surface (42), and energized to induce a shear wave (44) in the plies to heat the plies. The horn is moved along the upper most ply to consolidate the plies and the energy level applied to the horn is sufficient to reduce the viscosity of the thermost resin to the point where the plies can be debulked but not enough to fully cross-link the resin so that another ply can still be fully cross-linked to the uppermost ply. Pressure is applied to the plies as the horn moves to debulk the plies.
摘要:
A process for transmission laser welding of a first plastic part (12) and a second plastic part (14) that can be at least partially received in the first plastic part (12) is proposed. The second plastic part (14) is introduced into the first plastic part (12), to which it is connected by means of an interference fit connection, whereby at least one contact zone between the second plastic part (14) and the first plastic part (12) is formed as a result of this interference fit. A laser beam (30) is directed to impinge on the second plastic part (14), through the first plastic part (12), along the at least one contact zone to form a weld (32).