A casting method for super duplex stainless steel 5A impeller

A technology of duplex stainless steel and impeller, which is applied in the direction of casting molding equipment, casting mold, casting mold composition, etc., can solve the problems of sand slag hole and air hole defects, unfavorable feeding, high temperature of molten metal, etc., to solve crack defects, casting Reduce production cost and ensure the effect of casting structure

Active Publication Date: 2018-12-21
LUOYANG SUNRUI SPECIAL EQUIP
View PDF7 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The disadvantage is that the temperature of the molten metal at the bottom is high after filling the mold, which is not conducive to shrinkage; the gating system consumes a lot of molten metal, and the process yield is low; the slag and gas gathering effect of the gating system is poor, and the castings are prone to sand, slag and pores Defects; when the pouring temperature is low, it is easy to form cold shut defects

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 casting method for super duplex stainless steel 5A impeller
  • A casting method for super duplex stainless steel 5A impeller
  • A casting method for super duplex stainless steel 5A impeller

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0029] A casting method for an impeller made of super duplex stainless steel 5A, including internal control composition design, casting process, casting mold and sand core manufacturing process, smelting, pouring process, and heat treatment process for sand falling heat charging furnace.

[0030] (1) Design of internal control components: In order to improve the corrosion resistance of super duplex stainless steel castings, the content of ferrite phase and austenite phase should each account for about half (ferrite content is 40-60%). Control and design the content of austenite forming elements. The designed internal control composition range is: C≤0.025%, Si: 0.30~0.8%, Mn: 0.50~1.0%, P≤0.035%, S≤0.025%, Cr : 24.0~25.0%, Ni: 7.0~8.0%, Mo: 4.3~4.8%, N: 0.15~0.25%, PREN value: %Cr+3.3%Mo+16%N≥40.

[0031] (2) Manufacturing process of molds and sand cores: the molding materials of molds and sand cores are made of alkaline phenolic resin sand, and the molds and sand cores are mad...

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

PropertyMeasurementUnit
thicknessaaaaaaaaaa
diameteraaaaaaaaaa
heightaaaaaaaaaa
Login to view more

Abstract

A casting method for a super duplex stainless steel 5A impeller. The casting mold and sand core are made by adding alkaline phenolic resin to raw sand. The casting mold is made into an impeller cavity with a sand core. A foam ceramic filter is placed in the riser, and the finished impeller is obtained by casting and pouring, sand shakeout and hot charging furnace heat treatment. This can avoid the temperature range where brittle phases (eta, χ and σ phases) precipitate, and avoid the precipitation of brittle phases in the impeller casting structure. Fundamentally solving the crack defects of impeller castings can also ensure the dense structure of castings, and the casting yield can be increased to more than 96%. At the same time, with the improvement of process yield and the implementation of hot charging furnace technology, casting production costs have been significantly reduced.

Description

Technical field [0001] The invention belongs to the application field of casting technology, and particularly relates to a casting method of an impeller made of super duplex stainless steel 5A. Background technique [0002] As a key component of the pump, the impeller is directly related to the working efficiency of the pump. Its spatial surface is complex, and its size and blade shape require high accuracy. It requires double-sided dynamic and static balance testing. At the same time, as the power component of the pump, the impeller also bears Fluid corrosion, erosion corrosion, cavitation corrosion, etc. require the material to have a certain degree of corrosion resistance, a dense structure, and no casting defects. [0003] ASTM A890 5A material is the third generation duplex stainless steel. Its composition range is C≤0.030%, Si≤1.0%, Mn≤1.5%, P≤0.040%, S≤0.040%, Cr: 24.0~26.0%, Ni: 6.0~8.0%, Mo: 4.0~5.0%, N: 0.10-0.30%. Compared with ordinary duplex stainless steel, i...

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): B22C9/28B22C9/02C22C38/44C22C38/04C22C38/02C21D9/34
CPCB22C9/02B22C9/28C21D9/34C21D2211/001C21D2211/005C22C38/001C22C38/02C22C38/04C22C38/44
Inventor 邵世单陈亚涛关军胜靳新锋王灵水赵贵林
Owner LUOYANG SUNRUI SPECIAL EQUIP
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
Try Eureka
PatSnap group products