Rail grinding and its impact on the wear of wheels and rails. rail grinding and its impact on the wear of wheels and rails 3 2 the wheelrail contact as the outer rail in a curve is situated higher in a curve due to canting, it is called the high rail the inner rail is lower than the outer rail and is therefore called the low rail the inside of the rail head facing the other rail The vertical shaft impact crusher is also called sand maker. star trace develop this domestic, international, advanced level efficient crushing equipment combining the actual situation in domestic sand making, and it is based on the stone hit stone principle and technology. it is widely used in all kinds of hard and brittle materials for Rail head profile grinding machine robel a guiding mechanism forces the rail guiding discs to turn with the pivoting grinding unit. this stops the machine from slipping while maintaining a constant grindstone contact pressure and creating a true copy of the rail head and its profile over a pivoting range of 184 .