Gated pattern is used to produce good casting. It is essential to make sure that full supply of molten metal flow into every part of the mould. Provision for easy passage of the following molten metal into the mould is called "gatting". For improving the productivity of a moulder, the hand cutting of the gates must be eliminated.

In mass production a number of castings are produced in a single mould having multi cavity, by joining a group of patterns. For this purpose the gate or runners, for the flowing of the molten meta, are formed between the individual patterns. The time spent by the moulder in cutting gates, runners and withdrawal of individual patterns is eliminated by this arrangement. Such groups of patterns with gatting system are called "Gated Patterns".