Eureka AIR delivers breakthrough ideas for toughest innovation challenges, trusted by R&D personnel around the world.

A Method for Reducing Internal Cracks in Temperature Sensitive Large Length-to-Diameter Ratio PBX Forming

A temperature-sensitive, large aspect ratio technology, applied in non-explosive/non-thermal agent components, explosives, non-explosive fillers/gelling agents/thickeners, etc., can solve penetrating cracks, grain heat, force Problems such as uneven distribution, weapon detonation performance, mechanical performance and safety performance, etc., achieve the effect of reducing cooling temperature and reducing thermal stress

Active Publication Date: 2020-04-28
INST OF CHEM MATERIAL CHINA ACADEMY OF ENG PHYSICS
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] However, as the length-to-diameter ratio continues to increase, the heat and force distribution inside the grain becomes more uneven. When the length-to-diameter ratio exceeds 1, the grain will form internal longitudinal and horizontal stresses due to excessive elastic rebound and rapid internal stress release. Interlaced cracks, some even appear penetrating cracks, which have a negative impact on the detonation performance, mechanical properties and safety performance of weapons

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • A Method for Reducing Internal Cracks in Temperature Sensitive Large Length-to-Diameter Ratio PBX Forming
  • A Method for Reducing Internal Cracks in Temperature Sensitive Large Length-to-Diameter Ratio PBX Forming
  • A Method for Reducing Internal Cracks in Temperature Sensitive Large Length-to-Diameter Ratio PBX Forming

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0023] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0024] as attached figure 1 As shown, it is a schematic diagram of a conventional device for the compression molding process. The top is the upper punch, the middle is the mold sleeve, and the bottom is the base. figure 1 The left side shows the temperature characteristics of the existing conventional compression molding process. It can be seen that the temperature gradually increases from the base to the upper punch. figure 1 As shown on the right, the temperature of the base is higher than the temperature of the die sleeve, the temperature of the die sleeve is higher than the temperature of the upper punch, the temperature difference between the adjacent base temperature and the temperature of the die sleeve, the temperature of the die sleeve and the temperature of the upper punch, that is, the temperature gradient Greater than 5°C, not high...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses a method for reducing molded inner cracks of temperature-sensitive type PBX with a large length-diameter ratio. Based on the technological base of a developed die pressing molding technology, a temperature inverse compensation method is introduced; the temperature of a base is higher than that of a mold sleeve; the temperature of the mold sleeve is higher than that of an upper punch; the temperature difference value between the temperature of the base and the temperature of the mold sleeve, and between the temperature of the mold sleeve and the temperature of the upperpunch, i.e., a temperature gradient, is greater than 5 DEG C and not higher than 15 DEG C. The method disclosed by the invention mainly adopts a combined temperature inverse compensation method; the temperature of the base is improved so that the temperature of the base is higher than the temperature of the mold sleeve and the temperature of the mold sleeve is higher than the temperature of the punch. By adopting the temperature compensation method, thermal stress caused by temperature difference between upper and lower end faces in a propellant grain molding process is reduced; furthermore, effective pressure, which is reduced due to friction, on a propellant grain with the large length-diameter ratio is further properly compensated. The method can be used for reducing the inner cracks ofthe propellant grain, and also can be used for effectively improving the uniformity in the propellant grain.

Description

technical field [0001] The invention relates to a method for reducing internal cracks in explosive moldings, in particular to a method for reducing internal cracks in temperature-sensitive large-length-to-diameter ratio PBX molding, and belongs to the technical field of explosive molding. Background technique [0002] Large length-to-diameter ratio temperature-sensitive press-fit polymer bonded explosives (PBX), such as RDX-based PBX, are used in weapons due to their high mechanical strength, strong detonation ability, and good reliability. system. [0003] However, as the length-to-diameter ratio continues to increase, the heat and force distribution inside the grain becomes more uneven. When the length-to-diameter ratio exceeds 1, the grain will form internal longitudinal and horizontal stresses due to excessive elastic rebound and rapid internal stress release. Interlaced cracks, some of which even appear penetrating cracks, have adverse effects on the detonation perform...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): C06B21/00C06B25/34C06B23/00
CPCC06B21/0025C06B21/0041C06B23/001C06B25/34
Inventor 吕珂臻董向阳韩超杨坤徐程洪张锋冯立羊
Owner INST OF CHEM MATERIAL CHINA ACADEMY OF ENG PHYSICS
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Eureka Blog
Learn More
PatSnap group products