All castings must undergo a heat treatment to achieve the specified mechanical properties. Unless otherwise stated in the survey and order or agreed upon between the buyer and the manufacturer, all, must be properly “heat treated to make them tough and ductile. This treatment consists of uniformly heat the castings to a suitable temperature, holding them until they are evenly heated throughout, and their temper with a minimum time lag in water for a minimum temperature of 1 040 c. The water must be stirred so as to avoid the formation of a blanket of steam around flows during tempering. In the case of students from 4 castings, alternatively they can be cooled air to the top 1 040 c If the maximum cutting thickness does not exceed 60 mm and if so agreed between the parties. All test bars must be properly marked identify with the castings they represent.
1 all castings, shall be free from defects that harm machining or usefulness of castings.
2 when it is necessary to remove the throws or doors to flame or arc, or a combination thereof, or by any 2
3 castings, must be heat-treated in a well built oven, with adequate means of temperature control, which would enable all castings to be heated uniformly to the necessary temperature.