CN104096818A

CN104096818A - Zinc alloy worm gear squeeze casting technology and die

Info

Publication number: CN104096818A
Application number: CN201410304155.4A
Authority: CN
Inventors: 薛铁山
Original assignee: Individual
Current assignee: Individual
Priority date: 2014-06-30
Filing date: 2014-06-30
Publication date: 2014-10-15

Abstract

The invention discloses a zinc alloy worm gear squeeze casting technology and a die. The technological process is as follows: casting alloy, die assembly, pressurizing, preserving the pressure, releasing the pressure, die splitting, die releasing of workblank and resetting, wherein the heat preservation temperature is 570-630 DEG C; the preheating temperature of the die is 150-250 DEG C; the rate of descent of a punch is 5-10 mm/s; the injection pressure is 30-100 MPa; the pressure maintaining duration is 40-120 s; the die comprises an upper die sleeve (3), a lower die sleeve (9), an upper die (4) and a lower die (8). The zinc alloy worm gear squeeze casting technology and the die have the characteristics of simple technology, strong practicality, and simple structure, convenience in use and simplicity and easiness for maintenance of equipment. A worm gear prepared by means of metal mold gravity casting is changed into squeeze casting, and the tensile strength and elongation of the worm gear are improved.

Description

A kind of Extrution casting technique of kirsite worm gear and mould

Technical field

The present invention relates to extrusion casint field, especially a kind of Extrution casting technique of kirsite worm gear and mould.

Background technology

Kirsite is owing to having the advantages such as good casting character, mechanical property, wear resistance, processing characteristics and cheap cost, be widely used in the more multi-field of modern industry as high-abrasive material, and part replaces the structural materials such as bronze, brass and cast iron.Such as, traditional Worm wheel of tractor generally adopts metal mold gravity casting, in view of kirsite crystallization range is wide and easy generation at the bottom of contracting coagulating property, worm gear coarse grains, the tissue looseness of preparation, easily produce shrinkage cavity and porosity, particularly worm-gear toothing root, plasticity, toughness and anti-wear performance are poor, early produce too fast wear phenomenon in the course of the work, mechanicalness noise is large, and brings potential safety hazard.Meanwhile, the blank of worm gear size that adopts metal mold gravity casting to prepare is larger, needs a large amount of machineds to be shaped, and causes the utilization rate of raw material and the energy low, and production cost increases.In recent years, the shaping preparation that extrusion casint is constantly used to kirsite has improved the performance of cost zinc alloy greatly.

Summary of the invention

The Extrution casting technique and the mould that the object of the invention is to propose a kind of kirsite worm gear, it has simple process, and exploitativeness is strong, equipment simple in structure, easy to use, the feature of easy maintenance.Worm gear prepared by metal mold gravity casting becomes extrusion casint, has improved tensile strength and the percentage elongation of worm gear.

The technical scheme that the present invention solves its technical problem employing is: technological process is for watering the demoulding → reset of alloy → matched moulds → pressurization → pressurize → pressure release → parting → blank; Wherein holding temperature is that the decrease speed that 570 ~ 630 DEG C of mold preheating temperatures are 150 ~ 250 DEG C of drifts is that 5 ~ 10mm/s injection ratio pressure is to be 40 ~ 120s 30 ~ 100MPa dwell time.

This mould is by Upper Die-sleeve, lower die-sleeve, upper die and lower die composition, patrix is embedded in Upper Die-sleeve by nut, counterdie is embedded in lower die-sleeve by nut, patrix and Upper Die-sleeve center are provided with steam vent, in lower die-sleeve, be provided with the heating rod that utilizes Resistant heating, the upper surface of counterdie is provided with overflow launder, counterdie inside has cooling water pipe, be arranged on drift for the push rod that worm gear base is ejected, push rod is through the through hole of Upper Die-sleeve and patrix, die cavity is the annular shape with many steps, interior die wall is provided with the tapering of 3 ° ~ 10 °, each step transition place of die cavity is provided with the fillet of R1 ~ R5.

The invention has the beneficial effects as follows that ZA 27 alloy is after extrusion casint, the obvious refinement of microscopic structure, mechanical property significantly improves.The tensile strength of extrusion casint ZA 27 alloy worm gear has improved 28.6% percentage elongation and has improved 139% compared with metal mold gravity casting.And it has simple in structure, easy to use, easy maintenance.

Brief description of the drawings

The structural representation of Fig. 1 mould of the present invention;

1. drifts in figure, 2. push rod, 3. Upper Die-sleeve, 4. patrix, 5. overflow launder, 6. die cavity, 7. cooling water pipe, 8. counterdie, 9. lower die-sleeve, 10. nut, 11. heating rods, 12. through holes, 13. steam vents, 14. running gate systems.

Detailed description of the invention

Below in conjunction with accompanying drawing, the present invention is further illustrated, as shown in Figure 1, in the extrusion casint of kirsite worm gear, is provided with the running gate system 14 of automatic propelling movement on extrusion casting machine die shoe.Kirsite is melted, when manipulator scoop dips after quantitative aluminium alloy, running gate system is advanced to mold center position automatically, aluminium alloy flows into die cavity through running gate system 14, the drift 1 of following extrusion casting machine declines and steadily advances aluminium alloy to die cavity, Quick-pressurizing makes aluminium alloy, and under High Pressure, crystallization and freezing is through the up die sinking of pressurize back punching head, and when die sinking, worm gear base is stayed patrix 4, and push rod 2 ejects worm gear base.

This mould is by Upper Die-sleeve 3, lower die-sleeve 9, patrix 4 and counterdie 8 form, patrix 4 is embedded in Upper Die-sleeve 3 by nut 10, counterdie 8 is embedded in lower die-sleeve 9 by nut 10, patrix 4 and Upper Die-sleeve 3 centers are provided with steam vent 13, in lower die-sleeve 3, be provided with the heating rod 11 that utilizes Resistant heating, the upper surface of counterdie 8 is provided with overflow launder 5, counterdie 8 inside have cooling water pipe 7, be arranged on drift 1 for the push rod 2 that worm gear base is ejected, push rod 2 is through the through hole 12 of Upper Die-sleeve 3 and patrix, die cavity 6 is the annular shape with many steps, interior die wall is provided with the tapering of 3 ° ~ 10 °, each step transition place of die cavity 6 is provided with the fillet of R1 ~ R5.

ZA 27 alloy worm gear Extrution casting technique flow process is: water the demoulding → reset of alloy → matched moulds → pressurization → pressurize → pressure release → parting → blank; Wherein holding temperature is that the decrease speed that 570 ~ 630 DEG C of mold preheating temperatures are 150 ~ 250 DEG C of drifts is that 5 ~ 10mm/s injection ratio pressure is to be 40 ~ 120s 30 ~ 100MPa dwell time.

Should be understood that, for those of ordinary skills, can be improved according to the above description or convert, and all these improvement and conversion all should belong to the protection domain of claims of the present invention.

Claims

1. the Extrution casting technique of a kirsite worm gear, technological process, for watering the demoulding → reset of alloy → matched moulds → pressurization → pressurize → pressure release → parting → blank, is characterized in that: holding temperature is that the decrease speed that 570 ~ 630 DEG C of mold preheating temperatures are 150 ~ 250 DEG C of drifts is that 5 ~ 10mm/s injection ratio pressure is to be 40 ~ 120s 30 ~ 100MPa dwell time.

2. the squeeze casting mould of a kirsite worm gear comprises: Upper Die-sleeve (3), lower die-sleeve (9), patrix (4) and counterdie (8), patrix (4) is embedded in Upper Die-sleeve (3) by nut (10), counterdie (8) is embedded in lower die-sleeve (9) by nut (10), patrix (4) and Upper Die-sleeve (3) center are provided with steam vent (13), in lower die-sleeve (3), be provided with the heating rod (11) that utilizes Resistant heating, the upper surface of counterdie (8) is provided with overflow launder (5), counterdie (8) inside has cooling water pipe (7), be arranged on drift (1) for the push rod (2) that worm gear base is ejected, push rod (2) is through the through hole (12) of Upper Die-sleeve (3) and patrix, die cavity (6) is the annular shape with many steps, interior die wall is provided with the tapering of 3 ° ~ 10 °, each step transition place of die cavity (6) is provided with the fillet of R1 ~ R5.