Gyratory crushers and cone crushers, while looking the same and performing similar duties, are two different machines. A quick look at a machine will allow you to determine if it is a gyratory or a cone In simple terms, if you look at the top of the crusher and it has supporting arms (“spider arms”) going out to the centre of the machine (normally 2 or 3) it’s a gyratory. The presence of the spider arms is generally said to indicate that the crusher has a “restricted” feed opening (i.e. the arms may get in the way of the feed), whereas the cone crusher, without the spider arms, has an “unrestricted” feed opening This is a little misleading, however, as the gyratory’ crusher nearly always has a larger feed opening than an equivalent-sized cone crusher This is due to the shape of the crushing head, which in a gyratory, is a very steep cone where the head on a cone crusher is quite flat