The invention relates to a method for installing metallic fastener (10; 40) for the interference fit assembly of at least two structural elements (20, 22) comprising a through hole, the fastener comprising an enlarged head (12; 42), a shaft (14; 44) having an external diameter before installation that is greater than an internal diameter of the hole, said shaft comprising a conductive surface (26; 56). Before installation, at least the conductive surface (26; 56) is coated with a lubricating layer (30), which comprises a mixture of at least one polyolefin and one polytetrafluoroethylene, for example, having sufficient adherence to prevent its abrasion by manual manipulation of the fastener and being weak enough to be at least partly stripped from the conductive surface during the interference fit assembly of the fastener.

The invention is applicable to the assembly of aircraft structures.

The invention relates to a method for installing metallic fastener (10; 40) for the interference fit assembly of at least two structural elements (20, 22) comprising a through hole, the fastener comprising an enlarged head (12; 42), a shaft (14; 44) having an external diameter before installation that is greater than an internal diameter of the hole, said shaft comprising a conductive surface (26; 56). Before installation, at least the conductive surface (26; 56) is coated with a lubricating layer (30), which comprises a mixture of at least one polyolefin and one polytetrafluoroethylene, for example, having sufficient adherence to prevent its abrasion by manual manipulation of the fastener and being weak enough to be at least partly stripped from the conductive surface during the interference fit assembly of the fastener.

The invention is applicable to the assembly of aircraft structures.

In a threaded joint for pipes constituted by a pin and a box, each having a contact surface comprising a threaded portion and an unthreaded metal contact portion, the contact surface of the pin has a solid corrosion protective, preferably transparent coating based on a UV-curable resin and the contact surface of the box has a solid lubricating coating having plastic or viscoplastic rheological behavior which is preferably formed by the hot melt technique from a composition comprising a thermoplastic polymer, a wax, a metal soap, a corrosion inhibitor, a water-insoluble liquid resin, and a solid lubricant.

In a threaded joint for pipes constituted by a pin and a box, each having a contact surface comprising a threaded portion and an unthreaded metal contact portion, the contact surface of the pin has a solid corrosion protective, preferably transparent coating based on a UV-curable resin and the contact surface of the box has a solid lubricating coating having plastic or viscoplastic rheological behavior which is preferably formed by the hot melt technique from a composition comprising a thermoplastic polymer, a wax, a metal soap, a corrosion inhibitor, a water-insoluble liquid resin, and a solid lubricant.

Provided are low coefficient of friction fluoropolymer one coat coatings having a relatively low bake temperature. The fluoropolymer coatings contain high temperature resistant polymer binder, low melting tetrafluoroethylene/hexafluoropropylene copolymer having a melting point of below 255 C. by the method of ASTM D 4591, and low molecular weight polytetrafluoroethylene having a heat of crystallization of at least about 50 J/g.

Provided are low coefficient of friction fluoropolymer one coat coatings having a relatively low bake temperature. The fluoropolymer coatings contain high temperature resistant polymer binder, low melting tetrafluoroethylene/hexafluoropropylene copolymer having a melting point of below 255 C. by the method of ASTM D 4591, and low molecular weight polytetrafluoroethylene having a heat of crystallization of at least about 50 J/g.

The invention relates to a metallic fastener (10; 40) for the interference fit assembly of at least two structural elements (20, 22) comprising a through hole, the fastener comprising an enlarged head (12; 42), a shaft (14; 44) having an external diameter before installation that is greater than an internal diameter of the hole, said shaft comprising a conductive surface (26; 56). Before installation, at least the conductive surface (26; 56) is coated with a lubricating layer (30), which comprises a mixture of at least one polyolefin and one polytetrafluoroethylene, for example, having sufficient adherence to prevent its abrasion by manual manipulation of the fastener and being weak enough to be at least partly stripped from the conductive surface during the interference fit assembly of the fastener. The invention further relates to a method for obtaining such a fastener and to a method for installing such a fastener in a structure. The invention is applicable to the assembly of aircraft structures.

The invention relates to a metallic fastener (10; 40) for the interference fit assembly of at least two structural elements (20, 22) comprising a through hole, the fastener comprising an enlarged head (12; 42), a shaft (14; 44) having an external diameter before installation that is greater than an internal diameter of the hole, said shaft comprising a conductive surface (26; 56). Before installation, at least the conductive surface (26; 56) is coated with a lubricating layer (30), which comprises a mixture of at least one polyolefin and one polytetrafluoroethylene, for example, having sufficient adherence to prevent its abrasion by manual manipulation of the fastener and being weak enough to be at least partly stripped from the conductive surface during the interference fit assembly of the fastener. The invention further relates to a method for obtaining such a fastener and to a method for installing such a fastener in a structure. The invention is applicable to the assembly of aircraft structures.

A lubricating grease composition for a resin member is used to be supplied as a lubricant on a surface of at least a sliding portion of a resin member including the sliding portion with an other member. The lubricating grease composition for a resin member contains a base oil which is a mixed oil of a poly--olefin having a kinetic viscosity at 40 C. of 18 to 50 mm.sup.2/s and an ethylene--olefin copolymer having a number average molecular weight of 40,000 to 200,000, a lithium-based complex soap as a thickener and a polytetrafluoroethylene resin as a solid lubricant having a mixing ratio of 4 to 12 mass % to the entire lubricating grease composition, wherein the base oil has a kinetic viscosity at 40 C. of 80 to 200 mm.sup.2/s and a worked penetration of the lubricating grease composition ranges from 265 to 340.

A lubricating grease composition for a resin member is used to be supplied as a lubricant on a surface of at least a sliding portion of a resin member including the sliding portion with an other member. The lubricating grease composition for a resin member contains a base oil which is a mixed oil of a poly--olefin having a kinetic viscosity at 40 C. of 18 to 50 mm.sup.2/s and an ethylene--olefin copolymer having a number average molecular weight of 40,000 to 200,000, a lithium-based complex soap as a thickener and a polytetrafluoroethylene resin as a solid lubricant having a mixing ratio of 4 to 12 mass % to the entire lubricating grease composition, wherein the base oil has a kinetic viscosity at 40 C. of 80 to 200 mm.sup.2/s and a worked penetration of the lubricating grease composition ranges from 265 to 340.