Assembly for casting molten metal comprising a sand casting mould, a short-shroud, and a mould / shroud coupling mechanism, casting installation and method for casting a molten metal part

A kit-of-parts for casting molten metals comprising a short shroud, a sand casting mould, and a mould/shroud coupling mechanism,

• wherein the short shroud comprises,
• a shroud base attached to a proximal end of a short-shaft of a shaft length measured along a Z-axis, and having
• a shroud bore extending along the Z-axis from a shroud inlet opening at the shroud base to a shroud outlet opening at a downstream end of the short-shaft,
• wherein the sand casting mould comprises,
• a casting cavity having a cavity inlet,
• a housing selected among a filter housing and a diverter housing, having a housing outlet in fluid communication with the cavity inlet and a housing inlet in fluid communication with,
• a bore extending over a bore length along the Z-axis between a bore inlet opening at an upper surface of the sand casting mould and a bore outlet opening at a downstream end at a level of the housing inlet, the downstream end comprising a bore choke,
• wherein the bore choke forms a bore constriction defining the bore outlet which opens in the housing with a reduction of a bore diameter of at least 10% along the Z-axis in a flow direction,
• wherein the mould/shroud coupling mechanism comprises,
• a seat member configured for receiving the shroud base and holding the short-shroud in a shroud casting position wherein the downstream end of the short-shaft is inserted in the bore,
• wherein the shaft length is shorter than the bore length such that in the shroud casting position, the downstream end of the short-shaft is separated from the housing inlet by a shaft-free distance which is proportional to the bore length by a proportionality factor,
• wherein the proportionality factor is at least 20%,
• wherein a penetration depth (the bore length−the shaft-free distance) of the short-shaft in the bore at the shroud casting position is at least equal to 3 cm,
• wherein the mould/shroud coupling mechanism comprises:
• a base member fixed relative to the upper surface,
• wherein the base member and the seat member each comprise a central hole aligned with one another to define a lead-in towards the bore for the shroud,
• wherein the seat member is coupled to the base member by at least one compliant element such that the seat member is separated from and movable relative to the base member from a seat rest position to a seat casting position upon application of a load parallel to the Z-axis onto the seat member which deforms the at least one compliant element so as to drive a short-shroud sitting in the seat member to reach the shroud casting position, and
• wherein the at least one compliant element comprises one or more resilient elements including a spring, extending between the seat member and the base member.