342 results about "% diameter reduction" patented technology

A method of assembling of a stent graft (20) including temporarily diameter reduction arrangements to enable partial release of a stent graft to assist with positioning before complete release. The diameter reduction arrangement includes a release wire (72) and flexible threads (74, 80) extending to struts (76) of a self expanding stent (70) either side of the release wire and being pulled tight. Removal of the release wire enables full expansion of the self expanding stent.

A valve assembly and diameter reduction structure for trocar employing a movable diameter reduction structure. The diameter reduction structure is positioned in proximity to a first seal and includes a plurality of stand off members movable between a first position, a second position, and a third position. The diameter reduction structure in the first position reduces the likelihood of the first seal losing its integrity by limiting excessive off-axis and angular movements of small diameter surgical instruments. When large diameter surgical instruments are positioned through the trocar, the diameter reduction structure pivots to accommodate the passage of larger diameter surgical instruments without any operational adjustments.

A system for reducing the diameter of a stent comprises a stent contracting assembly and a fluid source. The assembly comprises a plurality of contracting members that define a diameter reduction chamber for receiving a stent. When the chamber is in a pre-reduction configuration the stent has a first diameter and when the chamber is in a reduced configuration the stent has a second diameter. The second diameter is less than the first diameter. The fluid source is in fluid communication with the chamber and is constructed and arranged to inject a fluid therein. The fluid forms a fluid bearing between the contracting members and the stent which prevents the contracting members from contacting the stent in the reduced diameter configuration.

An emergency redundant mounting flange is provided for incorporation into an oil-well blow-out-preventer (BOP), enabling rapid, tight-fitting attachment of an oil containment cap over a BOP outflow port in an emergency. This flange extends radially outward from the protected port, and includes an annular region with a connection feature, such as a ring of bolt-holes, permitting cap attachment. The cap, also provided, is a barrel-shaped diameter-reduction pipe which can be connected onto the emergency mounting flange at its bottom end, and onto a standard riser pipe at its top end, thus containing or stopping the flow of oil. After installation, the cap fully encloses the protected port, while creating a tight seal with the emergency mounting flange. Extension of these methods to bell-and-spigot plumbing fixtures, including reinforced concrete pipe, is also provided.

The invention provides a TC4 titanium alloy seamless tube and a production method thereof. The method comprises the steps of heating a round billet of a TC4 titanium alloy to 920-980 DEG C; conducting on-line hot centering on the round billet; conducting cross piercing, wherein controlling the total diameter reduction rate to be 9-16%, controlling the before-head reduction rate to be 2.5-11%, controlling the ovality coefficient to be 1.13-1.20, and controlling the punching rate to be 0.2-0.5m/s; conducting precise skew rolling to form a pierced billet, enabling the total diameter reduction rate to be 12-18%, enabling the ovality coefficient to be 1.08-1.15, enabling the tube rolling rate to be 0.3-0.4m/s; controlling the temperature of the pierced billet to be 860-940 DEG C, sizing and conducting air cooling to obtain the TC4 titanium alloy seamless tube. By means of the production method, the TC4 titanium alloy seamless tube with the excellent mechanical property can be obtained, production efficiency is high, mass production can be achieved, and the yield can reach 90% and more.

The invention discloses an overlaying welding agent core welding wire with abrasive wear resistance. A steel strip is wrapped with alloy powder and is subjected to drawing path by path and diameter reduction through a wire-drawing die to form the overlaying welding agent core welding wire, wherein the diameter of the overlaying welding agent core welding wire is between 2.4 and 3.2 mm; the length of the overlaying welding agent core welding wire is freely set; the steel strip is one of an SPCC steel strip, a 08A steel strip and a 08Al steel strip with width of between 18 and 22 mm and thickness of 0.45 and 0.6 mm; and the aluminum alloy powder is manufactured from waste steel and an alloying agent. The overlaying welding agent core welding wire is designed according to the composition requirement of overlaying welding metal; and compositions are fully homogenized in the smelting process of pulverization, thereby overcoming the disadvantages that the prior medicine powder for producing the overlaying welding agent core welding wire adopts a mechanical mixing process to easily cause unevenness of the compositions. The overlaying welding agent core welding wire uses the waste steel as one of raw materials of the overlaying welding agent core welding wire with abrasive wear resistance, fully utilizes contained alloy elements, improves the utilization rate of the alloy elements, reduces the cost for the overlaying welding agent core welding wire and achieves the aims of energy conversation and emission reduction.

An ultrafine fluid jet apparatus comprising a substrate arranged near a distal end of an ultrafine-diameter nozzle to which a solution is supplied, and an optional-waveform voltage is applied to the solution in the nozzle to eject an ultrafine-diameter fluid droplet onto a surface of the substrate; wherein an electric field intensity near the distal end of the nozzle according to a diameter reduction of the nozzle is sufficiently larger than an electric field acting between the nozzle and the substrate; and wherein Maxwell stress and an electro-wetting effect being utilized, a conductance is decreased by a reduction in the nozzle diameter or the like, and controllability of an ejection rate by a voltage is improved; and wherein landing accuracy is exponentially improved by moderation of evaporation by a charged droplet and acceleration of the droplet by an electric field.

A system for reducing the diameter of a stent comprises a stent contracting assembly. The assembly comprises a plurality of blades, which define a diameter reduction chamber. The chamber has an open diameter configuration and a closed diameter configuration. The plurality of blades comprises active blades and floating blades, wherein each active blade is engaged to an actuation mechanism. The actuation mechanism is constructed and arranged to move each active blade from the open diameter configuration to the closed diameter configuration. Each floating blade is moved from the open diameter configuration to the closed diameter configuration only as a result of the movement of the active blades.

The invention discloses the rolling technology of a fewer stander longitudinal hot rolling small diameter thin wall seamless steel tube which uses a heating furnace to heat a pierced billet to 950 DEG C to 1150 DEG C, a mandrel trolley pushes a mandrel into the heating pierced billet and is pushed to move forward, and the pierced billet is pushed into a wall reduction rolling unit that is formed by a plurality of wall reduction rolling mills to lead the pierced billet to be carried out longitudinal wall reduction rolling; the pierced billet that breaks away from the mandrel continues to be pushed into a stretch reducing rolling unit that is formed by a plurality of stretch reducing rolling mills to lead the pierced billet to be carried out longitudinal stretch reducing rolling until the rolling is finished; the pierced billet is put into a cold bed to cool; a straightening machine is used for straightening; a finished product is used for delivering and cutting; a flat head machine is used and a detecting machine is used for inspecting; a hydrostatic testing machine is used for detecting; the finished product is bundled and is put in storage. The invention uses the combination of the three-roll longitudinal rolling technology and a retained mandrel to adjust the straight roller longitudinal rolling with umbrella-shaped gears hydraulically and preciously to carries out diameter reduction and wall reduction rolling, and a rolled tube pipeline main control cabinet is used for operating stepless speed regulation of various stands so as to guarantee implementation of the technology, thus rolling the small diameter thin wall seamless steel tube with the diameter of Phi 12mm to Phi 76mm and wall thickness of 1mm to 6mm.

The invention discloses a new production process of a large seamless steel pipe. The process comprises the following steps: pipe billets are preheated to the temperature of 1050-1290 DEG C by a heating furnace, and delivered to a three-roll skew rolling piercing mill for piercing by a skew roll table conveying mechanism to finish diameter expansion and wall reduction rolling, the maximal ratio of diameter to wall D/S is over 32, and hollow billets are produced; the hollow billets are delivered to a three-roll skew rolling elongating finishing mill by a shift oblique orbit conveying mechanism to finish diameter expansion and wall reduction rolling or diameter reduction and wall reduction rolling, and the pierced billets are rolled, straightened, cropped end, cut to length, defect are detected, and the finished products are obtained after passing inspections. The new production process also perfects and improves the conventional three-roll skew rolling seamless steel pipe process, solves the problems of not rolling thin walls and great extension in the three-roll skew rolling process, the diameter expansion and wall reduction rolling can be carried out, and the diameter reduction and wall reduction rolling can be carried out. The new production process is especially suitable for rolling large and oversized seamless steel pipes (Phi is 500-2000mm), the ratio of single reduced diameter and expanded diameter is more than 30%, the reduced wall diameter is more than 70%, and the reduced wall thickness is 5-7 times of that of a longitudinal pipe rolling mill.

The invention relates to the technical field of metal plastic forming processes and equipment, and provides a shaft part two-roller flexible oblique rolling forming device and method. The device comprises two oblique rollers, a guide plate, two guiding cylinders and an axial pushing device; the oblique rollers can do motions including same direction rotation, radial feeding and oblique angle adjustment; the guide plate is arranged between the two oblique rollers and is used for limiting radial movement of a blank; the two guiding cylinders are arranged on the two sides of the two oblique rollers to limit swing of the blank; and the axial pushing device is arranged at one end of the blank and applies axial thrust to the blank, the blank is rolled into a shaft part in a space formed by the oblique rollers and the guide plate. The method includes radial compression, roller tilting, oblique rolling diameter reduction and roller leveling forming processes. The shaft part two-roller flexibleoblique rolling forming device and method have the advantages that forming equipment is simple, the tonnage is small, flexible production can be achieved, and core loose defects can be reduced even avoided.

A method of manufacturing a catalytic converter includes the steps of: a detecting step for detecting a pressing force at a time when a catalyst (11) is press-fitted into an outer cylindrical housing (13); a calculating step for calculating a diameter reduction, by which a clearance value between the outer cylindrical housing (13) and the catalyst (11) is set to a desired target value, based on the pressing force detected by the detecting step; and a swaging step for reducing a diameter of the outer cylindrical housing (13) based on the diameter reduction calculated by the calculating step.

The invention relates to a process of rolling a three-roll continuous rolling pipe, and belongs to the technical field of the production process of a hot rolled seamless steel pipe. The invention adopts a pipe rolling process by using a three-roll full-floating mandrel continuous rolling pipe; a diameter continuous casting round billet is used as a raw material; the heated raw material is pierced by a cone-shaped roll piercer, enters a continuous pipe rolling mill, and is rolled into an outside pierced billet; through the operation procedures of reheating, diameter reduction, etc., the high-quality small-caliber hot rolled seamless steel pipe is produced. By adopting the process of the three-roll full-floating mandrel continuous rolling pipe, the three-roll continuous rolling pipe achieves high production capacity (is twice as much as the production capacity by the traditional process), high metal yield (can be improved by 1.5 percent) and low consumption (energy resources can be saved by over 15 percent).

The invention relates to a flux-cored wire for welding low-temperature steel. The flux-cored wire comprises a cylindrical skin, wherein a through hole penetrating through the skin along the axis line is formed in the skin, and the through hole is filled with flux core powder composed of mineral powder, metal simple-substance powder (except rare earth elements), alloyed powder, metal oxide powder and rare earth. According to a preparation method of the flux-cored wire, the flux core powder is prepared first and then added into a U-shaped groove which is formed by drawing a steel belt; next, after an opening of the U-shaped groove is closed, the through hole penetrating through the steel belt is formed in the axial direction of the steel belt, and the flux core powder is arranged in the through hole; lastly, the flux-cored wire is obtained by means of step-by-step drawing and diameter reduction. The flux-cored wire can be welded in all directions, the welding efficiency is high, and weld joints are stable in metal performance and more attractive in appearance; besides, the average impact work of deposited metal at the low temperature of minus 60 DEG C can reach 65 J, so that the properties such as low-temperature impact toughness and low-temperature anti-cracking performance are improved to a higher grade.

A preparatory working device by which a work piece to be fed to a rack bar forging device is obtained. The device is provided with a die sets for obtaining a diameter reduction at a location of a blank pipe, which becomes a toothed part of a rack bar, while the wall thickness being substantially unchanged or slightly increased. The device is further provided with a die set for reducing a wall thickness at a location of the blank pipe, which becomes a connection part of the rack bar. The wall thickness reduction is one half of the initial thickness, which causes the length of the work piece to be elongated. Then a rack bar forging by a die set is done.