33results about How to "Uniform inner diameter" patented technology

Provided is a method of manufacturing a hollow microneedle structure. The method includes coating a hollow core having a predetermined section and being long in a lengthwise direction with a coating solution, and solidifying the coating solution to form a coating layer, depositing a metal seed layer on the coating layer, plating the seed metal layer with a metal to form a plated layer, cutting the hollow core having the plated layer at an inclination angle with respect to the lengthwise direction for form a surface inclination, and removing the hollow core and the coating layer to form a hollow microneedle structure. Thus, the hollow microneedle structure can be manufactured to have such diameter, length, hardness, and inclination angle as to minimize pain. By use of the hollow core, the microneedle structure can have vertical microneedles with a uniform inner diameter.

A rotary drill bit having blades with gage pads disposed on exterior portions thereof to improve steerability of the rotary drill bit during formation of a directional wellbore without sacrifice of lateral stability. One or more of the gage pads may include radially tapered exterior portions and / or cut out portions to assist with reducing wear of the associated gage pad. For some applications, a rotary drill bit may be formed having blades with gage pads having a relatively uniform exterior surface. Hard facing material and / or buttons may be disposed on exterior portions of the gage pad to form a radially tapered portion to improve steerability, reduce wear of the gage pad and / or improve ability of the rotary drill to form a wellbore having a generally uniform inside diameter, particularly during directional drilling of the wellbore.

A valve for controlling a fluid, in particular for controlling a gas. The valve includes a valve housing having a housing sleeve and an electromagnetic actuator for an armature which is guided in an axially displaceable manner and which cooperates with a valve seat situated on a seating plate so that a fluid flow through outflow orifices in the seating plate is controllable. The armature is guided along an armature sleeve which is situated in the housing sleeve.

A rotary drill bit having blades with gage pads disposed on exterior portions thereof to improve steerability of the rotary drill bit during formation of a directional wellbore without sacrifice of lateral stability. One or more of the gage pads may include radially tapered exterior portions and / or cut out portions to assist with reducing wear of the associated gage pad. For some applications, a rotary drill bit may be formed having blades with gage pads having a relatively uniform exterior surface. Hard facing material and / or buttons may be disposed on exterior portions of the gage pad to form a radially tapered portion to improve steerability, reduce wear of the gage pad and / or improve ability of the rotary drill to form a wellbore having a generally uniform inside diameter, particularly during directional drilling of the wellbore.

A hollow body molding device having molten resin injected into a main cavity, fluid is pressure-injected through a pressure port after the injection of molten resin, a floating core moves to the outlet side, the molten resin is extruded from the outlet simultaneously with the movement of the floating core, and a hollow molded body is molded, the hollow body molding device having a floating core storage portion connected to the main cavity and stores the floating core moved by the pressurized fluid, an auxiliary cavity stores molten resin discharged from the main cavity and the floating core storage portion, communication passages and which communicate the floating core storage portion and the auxiliary cavity with each other; and an opening and closing means that opens and closes the communication passages by sliding movement. In the hollow body molding device, each inlet cross-sectional area B of the communication passages is specified.

The invention relates to the technical field of a glass optical fiber material and a preparation method thereof, and especially relates to a single-mode chalcogenide infrared glass optical fiber and preparation method thereof. The optical fiber has the characteristics that: an As-S-Se infrared glass system is adopted as a coating layer, and an As-Se infrared glass system is adopted as a core layer. During a process for preparing an optical fiber preform rod, a coating sleeve pipe is prepared with a vacuum sealed rotary method; core-layer glass is prepared through vacuum sealed annealing; the core-rod glass rod is inserted into the coating sleeve pipe, and a core rod with a coating is prepared by using a wire-drawing machine; the core rod is inserted into the coating sleeve pipe again, and the single-mode optical fiber is prepared with a repeated drawing method. Through the regulation upon the composition of the coating glass, multi-coating chalcogenide glass optical fiber can be conveniently prepared. With the method, the prepared optical fiber has the advantages of controllable core-coating ratio; no defect such as impurity, bubble, or line on core-coating layer interface; high core-coating layer concentricity; and low optical loss.

The invention relates to a novel method for preparing a quartz needle by etching a capillary with hydrofluoric acid. Specifically, the polymer coating on the capillary tube to be etched is removed, then the capillary tube is fixed in the designed device (Figure 1), and a certain volume of hydrofluoric acid is added to etch the capillary tube until the capillary tube is etched and broken. The volatilization of hydrofluoric acid and the affinity with the quartz surface make the etched part of the quartz capillary form a conical surface. The method can be widely used in the preparation of quartz materials such as mass spectrometry electrospray needles and genetic engineering microinjection needles that need to control the outer diameter and the cone surface.

The present invention provides a method for preparing a hollow fiber catheter for nerve repair and a bundled structure thereof, which includes: preparing a mixed material containing at least one biodegradable polymer with an elongation at break of 30-1000% into an inner diameter of ≥0.3 mm tube; insert the rigid fiber into the tube and apply traction on both ends of the tube at normal temperature and pressure until the tube tightly covers the rigid fiber; remove the rigid fiber to obtain a hollow fiber catheter; use ammonia plasma to treat the hollow fiber The catheter is surface-treated; and then at least two surface-treated hollow fiber catheters are bonded into a bundle using biodegradable hydrogel to obtain a bundled structure for nerve repair. The method of the present invention can quickly and accurately prepare hollow fibers of different specifications, avoid the use of solvents, and produce bundled structures with a more microscopic orientation structure.

The invention discloses to a manufacturing method for a high-precision composite cloth guide roller body which relates to the technological field of textile, plastic, paper making and leather making,and the like, and more particularly relates to the technological field of textile printing and dyeing equipment. The invention comprises the following steps: a stainless steel external roller body anda cold rolled sheet roller body are rolled and welded respectively to form a stainless steel external roll blank and a cold rolled sheet roll blank; the cold rolled sheet roll blank is sheathed in the stainless steel external roll blank to make a double layer roll blank, and the spin-drawn forming is carried out at last. The method is the manufacturing method for the composite cloth guide rollerbody with good quality, reliable performance, low energy storage and high precision.

The invention relates to a prestressed thermal insulation oil casing. The prestressed thermal insulation oil casing is characterized by comprising an outer tube, a middle tube and an inner tube which are sleeved at intervals, wherein an internal thread is processed on one end of the middle tube, an external thread is processed on the other end of the middle tube, one end, which is provided with the internal thread, of the middle tube is welded with the outer tube at a tube end, and is welded with the inner tube at a reserved internal thread length position, one end, which is provided with the external thread, of the middle tube is welded with the outer tube at a reserved external thread length position, and is welded with the inner tube at a tube end; an annulus, which is formed by the outer tube and the middle tube, is filled with a thermal insulation material, and is vacuumized so as to form a first thermal insulation layer, after an annulus, which is formed by the middle tube and the inner tube, is vacuumized, inert gas is filled so as to form a second thermal insulation layer; the prestressed thermal insulation oil casing comprises the following production steps of pretreating three tubes, sleeving and welding the inner tube and the middle tube, treating the annulus of the inner tube and the middle tube, sleeving and welding the outer tube and the middle tube, treating the annulus of the outer tube and the middle tube, testing a visible heat conductivity coefficient and processing screw threads on two ends of the middle tube in sequence. The prestressed thermal insulation oil casing is provided with three layers of steel pipes and two layers of thermal insulation structures, so that the prestressed thermal insulation oil casing has good thermal insulation performance and excellent working performance.