A tubular threaded joint has a pin and a box. Each having a contact surface comprising a threaded portion and an unthreaded metal contact portion including a seal portion and a shoulder portion. A solid lubricating coating having a relatively high Knoop hardness is formed on a portion including the shoulder portion of the contact surface, such as the unthreaded metal contact portion including the shoulder portion and the seal portion, of at least one of the pin and the box. A solid lubricating coating having a relatively low Knoop hardness is formed at least on the remaining portion of the contact surface, such as the threaded portion. The threaded joint has excellent galling resistance, gas tightness, and rust preventing properties. The joint does not readily undergo yielding of shoulder portions even when made up with a high torque, thereby making it possible to perform makeup in a stable manner.

The invention concerns a threaded portion of a tubular element for a threaded tubular connection hiving an axis of revolution, the portion comprising a threading extending over its outer or inner peripheral surface, and a first sealing surface on the peripheral surface, the first sealing surface being capable of producing metal-metal interference with a corresponding second sealing surface belonging to a complementary threaded portion of a tube. The threading and the first sealing surface are coated with a metallic anti-corrosion and anti-galling layer wherein zinc (Zn) is tie major element by weight.

The invention concerns a threaded tubular connection for drilling or operating hydrocarbon wells, comprising a portion of a tubular element with a male end having an axis of revolution and provided with a first threading extending about the axis of revolution, said male end portion being complementary with a portion of a tubular element with a female end having an axis of revolution and provided with a second threading extending about the axis of revolution, said male and female end portions being capable of being connected by makeup, each of the male and female end portions further comprising a sealing surface with a metal-metal interference, wherein the threading and the sealing surface of one of the two, male or female, end portions are coated with a first metallic anti-corrosion and anti-galling layer wherein zinc (Zn) is the major element by weight, said first metallic anti-corrosion and anti-galling layer being coated with a first passivation layer, and the complementary threading and sealing surface of the male or female end are coated with a second metallic anti-galling layer wherein zinc (Zn) is the major element by weight, the second metallic anti-galling layer being at least partially coated with a lubricant layer comprising a resin and a dry solid lubricant powder dispersed in said resin.

The invention relates to lubricant additive compositions and lubricant compositions each comprising thiophosphates and thiophosphate derivatives, methods for making and using the same, including methods of lubricating machines and machine parts and methods of extending the useful life of elastomeric seal components of such machines.

An agent for forming a solid lubricating coating film on a thread portion of oil country tubular goods, in which a binder resin contains a prepolymer and a curing agent, the prepolymer is formed of one or more epoxy resins, 70 parts by weight or more of the prepolymer is contained with respect to 100 parts by weight of the binder resin, the epoxy resin constituting the prepolymer has an epoxy equivalent of 100 or more and 500 or less, the solid lubricant contains boron nitride (BN) in an amount of 80% by weight or more, BN has an average particle size of 10 ?m or less, and a total weight of the solid lubricant is 0.1 times or more and two times or less a total weight of the binder resin.

In a sliding shaft, an outer circumferential surface of a male shaft is coated with a resin coating layer formed by a fluidized bed powder coating method by using a powder coating material containing a base resin and an aliphatic compound. A steering device includes this sliding shaft as an intermediate shaft transmitting steering force.

The invention relates to thiophosphates and derivatives thereof useful as antiwear additive components, lubricant additive compositions and lubricant compositions each comprising such compounds, methods for making and using the same, including methods of lubricating machines and machine parts and methods of extending the useful life of elastomeric seal components of such machines.

Household lubricant compositions containing medium chain triglycerides are non-toxic and biodegradable. The lubricant compositions are made using vegetable oil components and stabilized using alcohol, an antioxidant, and a metal chelator. The lubricant compositions offer safe and environmentally friendly alternatives to petroleum-based lubricants, yet have similar lubricity and are more stable than naturally sourced vegetable oils. The compositions also can be used to clean and coat surfaces, including food preparation surfaces, and to prevent corrosion. Still further uses include sterilization and sanitation of surfaces and as a skin conditioner and lubricant.

There is provided a grease composition which is supplied between a plurality of lips provided in a sealing device that seals between a pair of members that rotate relative to each other, wherein the grease composition comprises a base oil (A), a thickening agent (B) and a rust preventive agent (C); a kinematic viscosity of the base oil (A) at 40 C. is 30 to 80 mm.sup.2/s; the thickening agent (B) is a diurea compound represented by Formula (1); and the composition comprises 5 to 15% by mass of the thickening agent (B) and 0.1 to 2.0% by mass of the rust preventive agent (C) based on the total of the grease composition.
R.sup.1NHCONHR.sup.2NHCONHR.sup.3(1) wherein R.sup.2 is a divalent aromatic hydrocarbon group having 6 to 15 carbon atoms, and R.sup.1 and R.sup.3 are a linear or branched alkyl group having 8 to 22 carbon atoms. Thus, a grease composition is provided, which can suppress a torque difference due to a rotation direction and exhibits excellent sealing properties.

The invention relates to thiophosphates and derivatives thereof useful as antiwear additive components, lubricant additive compositions and lubricant compositions each comprising such compounds, methods for making and using the same, including methods of lubricating machines and machine parts and methods of extending the useful life of elastomeric seal components of such machines.