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EP0032282A1 Expired / Lapsed EP ⏱️ 0.0 years remaining

Process for manufacture of cast iron with vermicular graphite and cast iron so produced

Assignee: Materials and Methods Ltd
•
Filing: 1980-01-15
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Granted: —
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Expires: 2000-01-15
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Abstract

Abstract A process for the production of cast iron with vermicular graphite in which molten grey cast iron is introduced in the mould cavity of a conventional pouring system which pouring system additionally includes one or more intermediate chambers containing a vermicularizing agent in an amount sufficient to convert the graphite at least in part to vermicular graphite. A nodular graphite inhibitor may be added to the molten grey cast iron before it is introduced in the mould cavity. By a particular selection of process parameters the amount of vermicularizing agent in the resulting cast iron may be closely controlled. The pouring system is known for the production of cast iron with nodular graphite but not the the production of iron with vermicular graphite. A pouring system is shown in the drawing and includes a downsprue (1), an intermediate chamber (2) which contains the vermicularizing agent, a gate (3), a runner bar and an ingate (5).

Inventors

  • 👤 Clifford Matthew Dunks
  • 👤 Geoffrey Mannion

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-10-30 12:34
CPC Classifications
C; C21; C21C; C21C1/00; C21C1/10

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 67 words
A process for the production of cast iron with graphite by casting molten grey cast iron into a mould cavity by way of a conventional pouring system which additionally includes one or more intermediate chambers characterized in that the intermediate chamber or chambers contain a vermicularizing agent in an amount sufficient to convert the graphite at least in part, to vermicular graphite under the process conditions employed.
Claim 2
Dependent Claim 67 words
A process for the production of cast iron with graphite by casting molten grey cast iron into a mould cavity by way of a conventional pouring system which additionally includes one or more intermediate chambers characterized in that the intermediate chamber or chambers contain a vermicularizing agent in an amount sufficient to convert the graphite at least in part, to vermicular graphite under the process conditions employed.
Claim 3
Dependent Claim 30 words
A process as claimed in claim 1, characterised in that a nodular graphite inhibitor is added to the molten grey cast iron prior to its introduction into the mould cavity.
Claim 4
Dependent Claim 73 words
A process as claimed in claim 1 or 2, characterised in that the amount of vermicularizing agent in the resulting cast iron is controlled by selection of process parameters according to the relationship:- area of the base or bases of the intermediate chamber or chambers = (factor) x (metal pouring rate) x (total concentration of the vermicularizing agent in the cast metal, expressed as a proportion of the weight of the cast metal).
Claim 5
Dependent Claim 23 words
A process as claimed in any of claims 1 to 3, characterised in that the vermicularizing agent is magnesium or an alloy thereof.
Claim 6
Dependent Claim 43 words
A process as claimed in claim 4, characterised in that the process is carried out such that the total concentration of the magnesium in the cast metal product expressed as a proportion of the weight of the cast metal is 0.01 to 0.02%.
Claim 7
Dependent Claim 22 words
A process as claimed in any of claims 1 to 5, characterised in that the molten grey iron contains titanium and/or zirconium.
Claim 8
Dependent Claim 25 words
A process as claimed in any of claims 1 to 6, characterised in that the cast metal product contains from 80 to 90% vermicular graphite.
Claim 9
Dependent Claim 18 words
Vermicular graphite-containing cast iron when made by a process as claimed in any of claims 1 to 7.

References Cited (Backward Citations)

GB1069058A Cited
GB1278265A Cited
GB1427445A Cited
GB1511246A Cited
DE2705630A1 Cited

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