Mould assemblies

摘要

Mould assemblies which comprise a container 302& 304 and a mould 406 & 408 where at least portions of an outer surface of the mould correspond to an inner surface of the container whereby the container supports the mould. In a first assembly at least one portion of a cavity in which an object can be formed by moulding is defined by the inner surface of the container. This portion of the cavity can be formed between adjacent and separate portions of the mould. In a second mould assembly the mould (Fig. 11) is formed of two or more segments assembled together to circumscribe a cavity in which an object can be formed by moulding and thereafter be inserted into the container. This assembly further includes a blank or displacement about which the mould segments are assembled. The assemblies can be used to make a steel or matrix bit head, a drill bit or a downhole component.