2299results about How to "Improve fatigue life" patented technology

A double shouldered high torque resistance threaded connection for drill stem components having enhanced resistance to torque forces, tensile loads and material stress and fatigue is disclosed. The tool joint is provided with threads having a 75 DEG included angle between the thread flanks thereof and with generally elliptical root surfaces to minimize material stress and fatigue during operation under high torque and high tensile loads. When made up, the double intrerengaging shoulders of the threaded tool joint are in firm face to face engagement permitting torque forces and tensile loads to propagate through the tool joint in a manner that minimizes bending forces and minimizes high stress concentration so that the resulting service life of the tool joint is significantly enhanced.

A low friction top coat over a multilayer metal/ceramic bondcoat provides a conductive substrate, such as a rotary tool, with wear resistance and corrosion resistance. The top coat further provides low friction and anti-stickiness as well as high compressive stress. The high compressive stress provided by the top coat protects against degradation of the tool due to abrasion and torsional and cyclic fatigue. Substrate temperature is strictly controlled during the coating process to preserve the bulk properties of the substrate and the coating. The described coating process is particularly useful when applied to shape memory alloys.

A Ball Grid Array package having an increased fatigue life and improved conductive pad adhesion strength, as well as providing sufficient wiring space within the package, is disclosed. In particular, solder joints having a combination of mask-defined and pad-defined solder joint profiles are formed using a mask having non-circular elongated openings. The non-circular elongated openings of the mask have a major axis and a minor axis, such that the dimension of the openings along the major axis is greater than the diameter of the conductive pads, and the dimension of the openings along the minor axis is less than the diameter of the conductive pads. In addition, the major axis of the openings within the mask are selectively oriented in the direction of highest stress for each solder joint within the package, while providing ample wiring space therein.

A large diameter rope having improved fatigue life on a sheave, pulley, or drum is disclosed. This rope includes a blend of HMPE filaments and liquid crystal polymer filaments selected from the group of lyotropic polymer filaments and thermotropic polymer filaments. The rope may be constructed as a braided rope, a wire-lay rope, or a parallel core rope.

A new interconnection scheme is disclosed for a tape automated bonding (TAB) package, a flip chip package and an active matrix liquid crystal display (AMLCD) panel, where an electrically conducting adhesive is used to form an electrical interconnection between an active electronic device and its components. The electrically conducting adhesive can be a mixture comprising a polymer resin, a no-clean solder flux, a plurality of electrically conducting particles with an electrically conducting fusible coating which provides a metallurgical bond between the conducting particles as well as to the substrates. The advantages of using the electrically conducting adhesives include reduction in bonding pressure and/or bonding temperature, control of interfacial reactions, promotion of stable metallurgical bonds, enhanced reliability of the joints, and others.

Aspects of the invention relate to a cooling system for a blade platform that can provide cooling to and reduce stress on the platform. Aspects of the invention relate to including one or more channels in the blade platform such that the channels extend from the trailing edge face of the platform toward, but terminate prior to, the leading edge face of the platform. The channels can be generally oval or oblong in conformation. Extending between the hollow shank and the channels can be a plurality of cooling holes. During engine operation, coolant is supplied to the shank of the blade assembly. Because the pressure at the shank is greater than the pressure at the trailing edge of the platform, coolant flow is induced through the cooling holes and into the channels. After flowing through the channels, the coolant can be dumped at the trailing edge.

An implantable lead for transmitting electrical signals between a proximal end and a distal end comprises an elongated lead body defining a longitudinally-extending lumen, and a plurality of individual electrical conductors contained in the lumen of the lead body and extending between the proximal and distal ends, the plurality of individual conductors sharing a common insulating coating. Each of the plurality of individual electrical conductors preferably comprises a braided, multifilar cable conductor. In one embodiment, the common insulating coating electrically isolates the plurality of conductors from each other, and may include a bridging portion extending between individual conductors.

The plurality of electrical conductors and the common insulating coating comprise a conductor assembly that may have a helical configuration defining a longitudinally-extending passageway for receiving a stylet, guide wire, or the like, for placement of the distal end of the lead. Alternatively, the conductor assembly may have a tubular configuration, the plurality of individual conductors being embedded therein in spaced-apart, parallel relationship or along a generally helical path along the length of the lead body for greater lead flexibility.

In an aspect, the invention relates to a decoupler that is positionable between a shaft (eg. for an alternator) and an endless power transmitting element (eg. a belt) on an engine. The decoupler includes a hub that mounts to the shaft, and a pulley that engages the endless power transmitting element, an isolation spring between the hub and the shaft. The decoupler provides at least a selected damping torque between the hub and the pulley.

Improved shape and strength of the weld in a welded structure are obtained by use of a weldable aluminum product comprising a structural component which is a sheet, a plate or an extruded body and is made of an aluminum alloy containing not more than 1.5 wt % Zn. This component has, adhered on at least one side, a cladding layer made of an AA7xxx-series alloy having a corrosion potential lower than that of the alloy of the structural component. The alloy of the structural component is preferably an AA5xxx-series alloy containing Mg in the range 2 to 6 wt %.

The invention discloses a production process of a 65 Mn spring steel wire rod and a 65 Mn spring steel wire rod. According to the invention, advantages of a device of a high line set are utilized, a finish rolling and reducing-sizing mills adopt 8+4 type, through optimization of a heating cycle process before rolling, a rolling control process and a cooling control process, only 8 front finish rolling machines and 2 reducing-sizing mills are utilized, so that surface decarburization of a spring is reduced and is even removed, and the fatigue life of a finished spring is prolonged; the amount of scales is reduced and the metal yield is improved; a metallographic structure is improved and a high sorbite rate is obtained, so that the production process has conditions to cancel a lead patenting process at the earlier drawing stage, the production processing cost is reduced, and the metallographic structure and the comprehensive performance of a hot-rolled wire rod for the 65 Mn spring steel are optimized. According to the invention, the microstructure quality and the mechanical property of the produced hot-rolled wire rod with phi6.5 mm for the 65 Mn spring steel reach the standard of the conventional 65 Mn spring steel after lead hot-rolled wire rod for the 65 Mn spring steel, the conditions to cancel the lead patenting process at the earlier drawing stage by a downstream user can be satisfied, a processing process is reduced for a user, and the production cost is reduced.

The invention discloses a manufacturing method of low-cost and high-purity medium-carbon bearing steel used for automobile hubs; the manufacturing method comprises the following steps: (a) the mass percentage of the components of the bearing steel is as follows: C: 0.55 percent to 0.58 percent, Si: 0.15 percent to 0.35 percent, Mn: 0.80 percent to 0.85 percent, P: less than or equal to 0.030 percent, S: less than or equal to 0.015 percent, Cr: 0.10 percent to 0.20 percent, Ni: less than or equal to 0.25 percent, Cu: less than or equal to 0.20 percent, Mo: less than or equal to 0.08 percent, Al: 0.008 percent to 0.015 percent, Ti: less than or equal to 30ppm, O: less than or equal to 15ppm, and the rest are Fe and inevitable impurities; (b) smelting, electric furnace initial melting+ ladle furnace refined melting+ vacuum degassing; (c) continuous casting into steel billet; (d) rolling. Compared with the prior art, the technological process has obviously shorter process and lower production cost; the impact resistance, torsion resistance, wear resistance and fatigue endurance of the produced automobile hub bearing are good.

Disclosed herein is an aluminum alloy clad sheet for a heat exchanger including a core layer, a sacrificial layer formed on one surface of the core layer, and a filler layer including an Al—Si based alloy formed on the other surface of the core layer. The core layer includes a predetermined amount of Si, Cu, Mn, Ti, and Mg, the remainder including Al and inevitable impurities, and the sacrificial layer includes a predetermined amount of Si, Mn, and Zn, the remainder including Al and inevitable impurities. The core layer has a crystal grain size after the brazing heat treatment at 595° C. for 3 minutes of at least 50 μm and less than 300 μm. The filler layer and the sacrificial layer are defined for their thickness, and the number of intermetallic compounds in the core layer is also defined to a predetermined range. By such constitution, the aluminum alloy clad sheet has improved fatigue life and post-braze strength, high corrosion resistance, and excellent erosion resistance and brazeability.

A lubricating oil composition for transmissions comprises a lubricating base oil comprising (A) a lubricating base oil so adjusted to have a kinematic viscosity at 100° C. of from 1.5 to 5 mm²/s and a % C_N of from 10 to 60 (B) a mineral lubricating base oil having a kinematic viscosity at 100° C. of from 10 to 50 mm²/s and a sulfur content of from 0.3 to 1 percent by mass and (C) a synthetic oil composed of carbon and hydrogen and having a number average molecular weight of from 2,000 to 20,000, in respective specific amounts and (D) an extreme pressure additive of from 0.05 to 2 percent by mass, based on the total amount of the composition, of comprising a phosphorus-based extreme pressure additive, a sulfur-based extreme pressure additive and/or a phosphorus-sulfur-based extreme pressure additive, wherein in the composition, the phosphorus content (P) is from 0.01 to 0.05 percent by mass, the total sulfur content (S) is from 0.05 to 0.3 percent by mass, and the P/S ratio is from 0.10 to 0.40. The lubricating oil composition has both excellent fuel economy performance and satisfactory durability for gears and bearings and furthermore excellent low temperature viscosity and oxidation stability.

The invention discloses a rolling method controlling network carbide precipitation of large-section GCr15 bearing steel. According to the method, GCr15 continuous casting billet serves as raw materials; and the following working procedures of heating, decaling, rough rolling, intermediate rolling, pre-finish-rolling, first time of water penetrating cooling, finish rolling of a rod reducing and sizing mill, second time of water penetrating cooling, cooling of a cooling bed and final obtaining of finished product rods are sequentially included. By means of the method, the level of the obtained network carbide of the large-section GCr15 bearing steel is reduced to be smaller than or equal to level 2 from the original level larger than or equal to level 3, the comprehensive mechanical performance of high-carbon-chromium bearing steel is improved, the service life of a bearing is prolonged, besides, the production cost is reduced, and the market competitiveness of the bearing steel is improved.

An axle/suspension system for a heavy-duty vehicle, in which the vehicle includes a frame that extends in a longitudinal direction relative to the vehicle. The axle/suspension system is attached to the vehicle frame via at least one hanger and includes at least one beam, which includes a first end and a second end. The first end of the beam is connected to the hanger, and the second end of the beam immovably captures an axle, which extends in a transverse direction relative to the vehicle. The beam is formed of a composite material and has a substantially constant cross section in the transverse direction to provide sufficient strength to control roll forces encountered by the vehicle during operation.

The invention provides a spring steel used for an automobile suspension. the spring steel comprises the following ingredients in percentage by weight: 0.46-0.56% of C, 0.90-1.20% of Si, 0.80-1.20% of Mn, less than or equal to 0.020% of P, less than or equal to 0.020% of S, 0.70-1.0% of Cr, 0.90-1.50% of Ni, 0.60-0.90% of Mo, 0.50-0.80% of Cu, 0.02-0.07% of RE and the balance of Fe and inevitable impurities. The invention also provides a preparation method for the spring steel and a method for preparing a spring steel wire by using the spring steel. According to the invention, the chemical components of the spring steel are reasonably designed, and the smelting rolling and steel wire preparation method and the auxiliary material adding method and proportion are improved. Compared with the existing 55SiCr steel, the tensile strength of the spring steel disclosed by the invention is improved by 400MPa, the working stress is improved by 200MPa, and the fatigue life is improved by 200 thousand times.