High nickel austenite spheroidal graphite cast-iron gas exhaust branch pipe casting technique

A technology of ductile cast iron and casting technology, which is applied in the direction of manufacturing tools, exhaust devices, casting equipment, etc., and can solve the problems of large thickness difference, high melting and pouring temperature, small exhaust pipe fittings and thin walls, etc.

Inactive Publication Date: 2007-03-07
西峡县内燃机进排气管有限责任公司
View PDF0 Cites 30 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The Si-Mo alloy ductile iron used in the past can no longer meet the requirements. The high-nickel austenitic ductile iron has been widely used in high-end vehicles because of its better heat resistance and corrosion resistance than Si-Mo alloy ductile iron.
However, because this kind of casting requires the material to be austenitic ductile iron D-5S with the highest nickel and silicon content, high alloy content and low carbon content, it is a complex material, the melting and pouring temperature is high, the casting process is poor, and the surface roughness of the casting is high. , and the exhaust pipe fittings are small and thin, with a large difference in thickness and high dimensional accuracy, especially for the dimensional accuracy of the three-dimensional curved surface of the flow channel. High-nickel austenitic ductile iron cannot use the existing casting process to produce automobile exhaust manifolds

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
  • High nickel austenite spheroidal graphite cast-iron gas exhaust branch pipe casting technique

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0029] The casting process of the high-nickel austenitic nodular cast iron exhaust manifold shown in Figure 1 includes core making, sand mixing, molding, smelting, pouring, cleaning, heat treatment, shot blasting, blank inspection, and blank storage.

[0030] Core making, sand mixing, molding, cleaning, shot blasting, blank inspection, and blank warehousing are manufactured according to the conventional exhaust manifold manufacturing process.

[0031] Wherein the main improvement process steps are:

[0032] 1. Melting:

[0033] Melting of High Nickel Austenitic Ductile Iron

[0034] A. Furnace charge and proportion

[0035] When the content of pig iron is 50% and the content of scrap steel is 50% as the main material, the content of trace harmful elements in the charge is: Pb_≤0.002% As≤0.005% Ti≤0.045%; When the main material is 98%, the fixed carbon content of the recarburizer is ≤98%, S≥0.03%, and the particle size is between 0.15-0.3%. The scrap steel is selected at a f...

Embodiment 2

[0047] Wherein the main improvement process steps are:

[0048] 1. Melting:

[0049] Melting of High Nickel Austenitic Ductile Iron

[0050] A. Furnace charge and proportion

[0051] When the pig iron content is 75% and the steel scrap content is 25% as the main material, the content of trace harmful elements in the charge is: Pb_≤0.002% As≤0.005% Ti≤0.045%; When the main material is 95%, the fixed carbon content of the recarburizer is ≤98%, S≥0.03%, and the particle size is between 0.15-0.3%. The scrap steel is selected at a fixed point, and the composition is uniform, so there is no rust and no impurities; Ni Add in the form of electrolysis, the addition amount is 38%, Cr is added as ferrochromium containing Cr60-65%, the addition amount is 2.2%, Si is added in the form of 75% ferrosilicon, the addition amount is 5.3%;

[0052] B. Melting control

[0053] When using pig iron and scrap steel as the main material, put the pig iron and scrap into the electric furnace crucib...

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 relates to a method for casting high-nickel austenite nodular graphite cast iron discharge branch tube. Wherein, the invention comprises preparing core, mixing sand, shaping, smelting, irrigating, thermally processing, machining, dropping, checking, and packing; the smelting comprises mixing material, controlling smelting, balling, and breeding, and the nickel is added at later period; adding chromium at overheated period of iron water; the balling agent is nickel magnesium silicon iron balling agent; the breeding agent is 75 silicon iron; the iron water is irrigated quickly to charge section; the irrigating temperature is 1460-1530Deg. C; the thermally processing increases the casting to 870-1000Deg. C; keeping temperature for 3-6hours, cooling to 620Deg. C, and discharging. The invention has high impact-resistance and worm-anti property, better corrosion-resistance and oxidization resistance.

Description

technical field [0001] The invention belongs to the technical field of automobile exhaust pipe processing, and in particular relates to a casting process of a high-nickel austenitic nodular cast iron exhaust manifold. Background technique [0002] High-nickel austenitic ductile iron was first successfully developed in the United States in 1925-1930, but until the 1960s, this material was still little known. After 1970, the production and application of this cast iron continued to develop, and it has been included in Western developed countries and the International Organization for Standardization. High-nickel austenitic nodular cast iron is a material with great development prospects. It has good comprehensive mechanical properties and process properties. The material is incomparable. In recent years, with the development of automobile engineering, nuclear power and marine engineering, it has been widely used in the manufacture of heat-resistant and corrosion-resistant pa...

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 Applications(China)
IPC IPC(8): B22D37/00C22C33/08C22C37/10C21D9/08C21D1/26F01N7/08F01N13/08
Inventor 程景胜李立新柴西成赵新武刘文生李长武
Owner 西峡县内燃机进排气管有限责任公司
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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap