Method for producing a fuel tank with internal accessories
Method for producing a fuel tank provided with internal accessories and having a wall made of plastic made in a single piece by moulding a split parison or a parison in at least two parts, said method comprising the following steps: a) the parison is introduced in the heat-softened state into a mould comprising dies; b) a core on which the accessories are placed is introduced inside the parison; c) the parison is pressed onto the dies of the mould; d) the accessories are fastened to the parison with the aid of the core in an ideal layout; e) the core is withdrawn and the mould is closed; f) the tank is moulded from the parison; and g) the tank is removed from the mould.
1. A method for producing a fuel tank;
the fuel tank comprising:
an internal component; and
a plastic wall obtained by moulding a parison;
the method comprising:
a) introducing the parison in a heat-softened state into a mould comprising dies;
b) introducing a core on which the internal component is placed inside the parison in the mould;
c) closing the mould and pressing the heat-softened parison onto the dies of the closed mould;
d) fastening the internal component to the parison with the aid of the core;
e) opening the mould and withdrawing the core from the opened mould;
f) closing the mould with the core withdrawn;
g) moulding the tank from the parison in the closed mould wherein an equilibrium of pressure is provided between the pressure inside the component and the pressure inside the tank; and
h) opening the mould and removing the tank from the opened mould.
2. The method according to claim 1 , further comprising making an orifice in the component for providing the equilibrium of pressure.
3. The method according to claim 2 , wherein
the component is an internal ventilation circuit comprising at least one valve and a small pipe,
the small pipe is fastened to the parison, and
the orifice is made in the small pipe fastened to the parison.
4. The method according to claim 2 , further comprising closing the orifice.
5. The method according to claim 4 , wherein closing the orifice is performed after the blow moulding phases.
6. The method according to claim 1 , wherein the tank comprises a multilayer structure, and the multilayer structure comprises at least one thermoplastic layer and at least one barrier layer.