A fluid end having its fluid flow bores sealed without threading a retaining nut into the walls of each bore. The fluid ends may be assembled using a plurality of different kits that each comprise a fluid end body, a component, a retainer element, and a fastening system. The retainer element holds the component within each of the bores formed in the fluid end body and the fastening system secures the retainer element to the body. The fastening system comprises a plurality of externally threaded studs, washers and nuts in some embodiments. In other embodiments, the fastening system comprises a plurality of screws.

A pin retention device comprises a fastener defining a longitudinal axis, a first end and a second end along the longitudinal axis, a head at the first end and a threaded portion at the second end, a tubular spacer defining a thru-hole configured to receive the fastener, and a nut defining a threaded hold configured to mate with the threaded portion of the fastener.

A pin retention device comprises a fastener defining a longitudinal axis, a first end and a second end along the longitudinal axis, a head at the first end and a threaded portion at the second end, a tubular spacer defining a thru-hole configured to receive the fastener, and a nut defining a threaded hold configured to mate with the threaded portion of the fastener.

The invention relates to a fastener comprising a substantially right circular cylindrical surface arranged along an axis, said surface comprising a grooved shape selected from a thread, a tapping and a plurality of traction grooves, said fastener being made of a beta-metastable titanium alloy. The alloy has a microstructure (40) made up of a matrix (42) and alpha phase nodules (44) distributed in said matrix, the matrix being made up of beta phase and groups (46) of alpha phase lamellae (48) oriented in the same direction.

The invention relates to a fastener comprising a substantially right circular cylindrical surface arranged along an axis, said surface comprising a grooved shape selected from a thread, a tapping and a plurality of traction grooves, said fastener being made of a beta-metastable titanium alloy. The alloy has a microstructure (40) made up of a matrix (42) and alpha phase nodules (44) distributed in said matrix, the matrix being made up of beta phase and groups (46) of alpha phase lamellae (48) oriented in the same direction.

The two lockable stainless and lossless screw pairs at two ends of the bolt are provided both to avoid screw pairs stained or destroyed by strain force from loading and to decrease the cost because of energy consumption in traditional process of bolt or its cost from environmental pollution.

An energy harvesting system, fastener, use of an energy harvesting system and method for the conversion of kinetic energy into electrical energy are provided, the harvesting system being made, at least partially, of a piezoelectrical material, wherein the fastener is configured to guarantee the joining of a plurality of components of a mechanical apparatus, and the method comprising conversion of kinetic energy into electrical energy at each junction area having the disclosed fastener.

A disclosed tolerance compensator system reduces or avoids bending of components when the components are fastened to each other, thereby increasing the reliability of the components. The limited number of parts of the tolerance compensator system simplifies manufacturing and reduces costs. A disclosed method for fastening components together using the tolerance compensator system reduces or avoids bending of components, increases the reliability of the components, reduces fastening times, and simplifies fastening procedures.

A stay rod assembly for a fluid pump has a rod with the first threaded section at one end and a second threaded section at an opposite end thereof with a stud portion located between the first threaded section and the second threaded section, and a sleeve positioned over the stud portion of the rod. The stud portion is tapered so as to narrow diameter from the first threaded section to the second threaded section. The stud portion has no shoulders thereon. The rod is received in an interior of the sleeve.

A stay rod assembly for a fluid pump has a rod with the first threaded section at one end and a second threaded section at an opposite end thereof with a stud portion located between the first threaded section and the second threaded section, and a sleeve positioned over the stud portion of the rod. The stud portion is tapered so as to narrow diameter from the first threaded section to the second threaded section. The stud portion has no shoulders thereon. The rod is received in an interior of the sleeve.