Patent GB-773684-A (GB)
Title: Improvements in or relating to lubricants for use in making shell moulds and cores
Inventor: WOODS ARTHUR
IPC: B22C1/22
Filed: 1953-01-30
Abstract: A lubricant, suitable for use in the manufacture of shell moulds and cores, comprises a mixture of unbleached montan wax and hydrocarbon oil having a viscosity at 140 DEG F. of 800-1200 secs.  Redwood I, a viscosity at 200 DEG F. of 230-330 secs. Redwood I, a viscosity at 300 DEG F. of 60-90 secs.  Redwood I and a Conradson carbon residue not exceeding 4 per cent.  A suitable hydrocarbon oil is that known under the Registered Trade Mark "Cresta."  In the preparation of the lubricant, 3-6 ozs. of unbleached montan wax may be mixed with 1 pint of the hydrocarobn oil, this mixture being diluted if necessary with up to 3/4 pint of kerosene, and only such heat being used as is necessary to effect adequate mixing.  The lubricant, which is in the form of a paste and is termed the conditioning agent, is applied to a heated metal pattern plate or core box which is to be used in making shell moulds or cores from a moulding mixture comprising sand and a thermosetting binder composition (including a synthetic resin and a hardening agent) in powder form.  The heated pattern plate or core box, coated with the conditioning agent, is given a coating of a lubricant termed a stripper before use.  The stripper may comprise a mixture of kerosene with a solution of unbleached montan wax in a hydrocarbon oil as defined above, the hydrocarbon oil solution forming not more than 40 per cent by weight of the mixture.  Such a stripper may be prepared by adding 3 ozs. of unbleached montan wax to 2 pints of the hydrocarbon oil, heating the mixture for half an hour to a temperature above the melting point of the wax but below the boiling point of the oil, cooling to atmospheric temperature, filtering and mixing with kerosene in the stated proportions.  The application of the coating of stripper may be repeated before each subsequent use of the heated pattern plate or core box, or at frequent intervals, for example at every third or fourth operation. Instead of the stripper mentioned above, there may be employed the solution of unbleached montan wax in kerosene referred to in Specification 677,434. Specifications 674,421, 674,422 and 754,112 [all in Group XXII] also are referred to.ALSO:Metal pattern plates or core boxes, which are to be used in making shell moulds or cores from a moulding mixture comprising sand and a thermosetting binder composition (including a synthetic resin and a hardening agent) in powder form, are coated with a lubricant which comprises a mixture of unbleached montan wax and a hydrocarbon oil having a viscosity at 140 DEG F. of 800-1200 secs. Redwood I, a viscosity at 200 DEG F. of 230-330 secs.  Redwood I, a viscosity at 300 DEG F. of 60-90 secs. Redwood I and a Conradson carbon residue not exceeding 4 per cent.  A suitable hydrocarbon oil is that known under the Registered Trade Mark "Cresta," In the preparation of the lubricant, 3-6 ozs. of unbleached montan wax may be mixed with 1 pint of the hydrocarbon oil, this mixture being diluted if necessary with up to 3/4 pint of kerosene, and only such heat being used as is necessary to effect adequate mixing.  The lubricant, which is in the form of a paste and is termed the conditioning agent, is applied to the heated pattern plate or core box, and the coated pattern plate or core box is then given a coating of a lubricant termed a stripper before use. The stripper may comprise a mixture of kerosene with a solution of unbleached montan wax in a hydrocarbon oil as defined above, the hydrocarbon oil solution forming not more than 40 per cent by weight of the mixture.  Such a stripper may be prepared by adding 3 ozs. of unbleached montan wax to 2 pints of the hydrocarbon oil, heating the mixture for half an hour to a temperature above the melting point of the wax but below the boiling point of the oil, cooling to atmospheric temperature, filtering and mixing with kerosene in the stated proportions.  The application of the coating of stripper may be repeated before each subsequent use of the heated pattern plate or core box, or at frequent intervals, for example at every third or fourth operation.  Instead of the stripper mentioned above, there may be employed the solution of unbleached montan wax in kerosene referred to in Specification 677,434 [Group III].  Specifications 674,421, 674,422 and 754,112 [all in Group XXII] also are referred to.