34results about How to "Low roundness" patented technology

The invention discloses a polylactic acid toughened material for 3D printing, which comprises polylactic acid and the following components in percentage by mass (on the basis of polylactic acid): 5-25% of toughener, 0.5-2.0% of lubricant, 0.5-2.0% of oxidized polyethylene wax, 0.3-1.0% of white oil, 5-25% of low-melting-point resin-coated inorganic powder and 0.3-0.9% of antioxidant. The material prepared by the technical scheme has the advantages of favorable toughness, high extrusion forming regularity and favorable line roundness. The printing proves that the product has the advantages of low shrinkage, no edge lifting, no cracking, high cooling speed and favorable appearance and has wide printing application range.

An outer blade cutting wheel comprising an annular thin disc base of cemented carbide and a blade section of metal or alloy-bonded abrasive grains on the outer periphery of the base is provided. The abrasive grains are diamond and / or cBN grains having an average grain size of 45-310 μm and a TI of at least 150. The blade section includes overlays having a thickness tolerance (T3max−T3min) of 0.001 mm to 0.1×T2 mm. The blade section has a roundness (ODmax / 2−ODmin / 2) of 0.001 mm to 0.01×ODmax mm.

The invention provides a double-layer composite pipe and a forming method thereof in order to solve the problem that in the prior art, as the contraction ratios of double-layer metal pipes are different and the machining process is complex, a complex-structure component can not be formed. The preparation method of the double-layer composite pipe includes the following steps that assembling is conducted, specifically, a hollow aluminum alloy pipe blank is arranged inside a hollow carbon steel pipe blank to form a double-layer composite pipe blank; forming is conducted, specifically, the double-layer composite pipe blank is arranged in an extrusion space, the extrusion space can be matched with the double-layer composite pipe blank, and a cavity in a target shape is formed; the hollow aluminum alloy pipe blank of the double-layer composite pipe blank is filled with medium particles; pressure is applied to the medium particles in the axial direction of the two ends of the double-layer composite pipe blank; and the double-layer composite pipe blank deforms to fill the cavity, and the double-layer composite pipe is formed. The double-layer composite pipe is easy to prepare, good in performance and capable of being used for manufacturing complex-structure pipe fittings.

A rotating portion of a motor includes a magnet, a yoke, and a hub. An upper portion of the yoke is fixed to the hub. The yoke includes a first inner circumferential surface radially opposite to an outer circumferential surface of the magnet with a first gap intervening therebetween, and a second inner circumferential surface radially opposite to the outer circumferential surface of the magnet with a second gap intervening therebetween below the first inner circumferential surface. The second inner circumferential surface is parallel or substantially parallel to the outer circumferential surface of the magnet, and is located radially outward of the first inner circumferential surface. An adhesive is provided in at least a portion of the first gap. No adhesive is provided in at least a lower axial end portion of the second gap.

The invention discloses a grinding and removing device for a spigot of an adjustable galvanized plate end cover. The grinding and removing device comprises a base, clamping devices, an inner gear disc, a rotating motor and a grinding device, wherein the clamping devices are arranged on the left side and the right side of the inside of a lifting table, the inner gear disc is fixedly welded to the lower side of a sliding strip through a connecting rod, a connecting shaft is arranged at the center wheel core of a second gear in an interference fit mode, and a grinding device is arranged at the lower end of the connecting shaft. According to the grinding device, the end covers with different diameters can be clamped, so that the universality of the device is greatly improved, and the purchasing cost of equipment is saved; a grinding head on the grinding device is driven to carry out planetary rotation, and the spigot in the end cover is ground, so that compared with manual grinding, the grinding speed of the grinding and removing device is higher; the intensity of grinding each spigot can be the same, the degree of roundness of the end cover caused by different grinding strength is avoided, and the single-machine noise of a motor during final assembly is guaranteed.

Provided is a large-diameter tube assembling and lifting tool. The large-diameter tube assembling and lifting tool comprises two arc-shaped inclasping pieces and two lifting pieces used for connecting the at least two arc-shaped inclasping pieces. The arc radiuses of the arc-shaped inclasping pieces are equal to the radius of a tube. The two lifting pieces are arranged on the extension line of the diameter of the tube, and a lifting hole is formed in each lifting piece. The lifting holes are used for connecting a lifting rope in a penetrating mode. Due to the fact that a circular ring is used to lift the large-diameter tube, gravity stressed by the large-diameter tube assembling and lifting tool can be evenly distributed on the circular ring, and therefore pressure on each portion of the tube is roughly equal. Thus, the phenomenon that circular degrees of the tube are reduced caused by uneven stress in the process of lifting can be avoided.

The invention discloses a casting system and casting method of a cylinder barrel. The casting system comprise a casting mold cavity and a pouring system, wherein the casting cavity comprises a cylinder barrel cavity body, a through hole is axially formed in the cylinder barrel cavity body, the cylinder barrel cavity body is composed of a cylinder barrel head part and a middle body part, the diameter of the cylinder barrel head part is larger than that of the middle body part, a radial protruding block is arranged on the cylinder barrel head part, and a supporting fixing hole and an oil passagehole are formed in the protruding block; the pouring system comprises a sprue, a transverse runner and an inner sprue, the sprue vertically communicates with the transverse runner, the two ends of the transverse runner communicate with the inner sprue through risers, and the inner sprue communicates with a convex block of the casting cavity; and the supporting fixing hole is filled with a first sand core, and an axial through hole of the cylinder barrel cavity body is filled with a second sand core. The casting system has the advantages that parts with the wall thickness of a casting are notprone to shrinkage and loosening defect generating, particularly, the casting defect is not easy to occur among the supporting fixing hole, the oil passage hole and the inner surface of the cylinder barrel, and a chill structure cannot be easily generated in parts with the thin wall thickness.

The invention discloses a method for planning a hole-making process trajectory of a laminated material, which comprises the following steps: 1) dividing the processing process of the laminated material into processing stages such as entry, stabilization, interface, and exit along the axial direction; 2) measuring and sorting out the hole-making accuracy 3) Analyze the variation law of the hole making precision at each stage, and establish the fitting relationship between the hole diameter deviation, roundness and the characteristic parameters of the spiral trajectory; 4) The average value of the axial cutting force is the smallest, and the peak value of the circumferential cutting force is the smallest As the goal, the optimal value of the characteristic parameters of the spiral trajectory is obtained. The invention provides a way to solve the problem of "inverted cone" in the through-hole processing of laminated materials. By analyzing the variation law of the hole-making precision in the key stage of the single-hole processing process, the core goal is to meet the precision level requirements of the export stage, and the spiral movement is carried out. Trajectory planning, and finally realize the optimization of process parameters, which can not only improve the overall hole-making accuracy of the single-hole machining process, but also help reduce the overall cutting force level to prolong the tool life.

The invention discloses an extensible and retractable inner supporting tool. One end of a left-handed screw is installed in a screw installation hole in the plane geometric center of a supporting plate, and the left-handed screw is in rotating fit with the screw installation hole. A left-hand thread at the other end of the left-handed screw is installed in a threaded hole in the center at one endof a sleeve. One end of a right-handed screw is installed in a screw installation hole in the plane geometric center of the other supporting plate, and the right-handed screw is in rotating fit with the screw installation hole. A right-hand thread at the other end of the right-handed screw is loaded in a threaded hole in the center at the other end of the sleeve. The extensible and retractable inner supporting tool has extending and retracting functions; in a shortened state, the extensible and retractable inner supporting tool can be put into a shell and then extends to support a cylinder, rigid restraining to the cylinder is achieved, and the welding deformation is reduced; and by means of stress relief annealing heat treatment through the belt tool, deformation stress is eliminated, andtherefore the cylinder circular degree after welding is guaranteed, and the circular degree of the shell is reduced to 2.5 mm from 10 mm.

The present invention provides a tyre element assembly drum capable of holding roundness even zooming radii of a segment mold. The drum forms the circular tyre element by winding tyre material on periphery surface of the drum. The drum comprises: a center shaft capable of being rotatably supported; a plurality of segment mold arranged surrounding the center shaft to form the periphery surface of the drum; a segment mold moving unit for moving the segment mold at drum neck in zoom manner. Each segment mold comprises a main segment mold slice moving in drum neck direction by using the segment mold moving unit; a bending segment mold slide capable of being fixed on a side edge on a side of main segment mold slide in circumferential direction in manner of cantilever and surrounding the axial line in the axial line of the drum. End of free end side of each bending segment mold slide is carried on outer surface of the main segment mold slide at other segment mold slide adjacent to the free end side, and is provided with a force applying unit for applying force on the bending segment mold slide to radial inner side of the drum.

The invention relates to a tool and method for correcting the shape of a composite cabin section and belongs to the technical field of composite component curing deformation. In the method, the shape of the composite cabin section is corrected by using the tool at set temperature so as to reduce the problems that the deformation of a composite component causes product scrap, or too-concentrated stress on the following processing and assembly and the like.

The invention discloses a processing method and tooling for a tube clamp part. The processing method and the tooling are used for processing a circular tube clamp part of which both ends are provided with small lugs. The circular tube clamp part also comprises a clamp ring and a tongue sheet. When the circular tube clamp part is formed by the processing method and the tooling, a closed die processing method is adopted. When the circular tube clamp part is bent, the die converges to the middle, and the circular tube clamp part is formed in a die cavity, so the outer circular size and the appearance quality of the circular tube clamp part are ensured, and the rebound is reduced. The tooling has the advantages that a half type upper and lower symmetrical structure is adopted, the structure is simple, the manufacture is easy, the shape is small, the manufacture cost is low, the shape of the die cavity of the tooling is the same as the shape of the circular tube clamp part, the circularity of the bent circular tube clamp part is good, the shape precision is high, and the production efficiency is high. The requirements on operation skills of operators are low, the assembly and disassembly are convenient, the production cost is low, and the circular tube clamp part has good size uniformity and stable quality.