As you know, bends - the most loaded sections of pipelines, which because of an area of turbulence occurs accelerated wear of the walls, because here is concentrated to abrasion and chemically active substances contained in the working environment. To minimize this phenomenon is widespread use of stone casting all along the pipeline, but in order to reduce capital costs sometimes straight sections still make out of the ordinary steel or cast iron pipes and curved portions are collected from lined taps.
Lining are mainly used basalt or diabase. Bends of stone casting characterized by high wear resistance and high chemical resistance and hence durability. Only through the use of inserts of stone casting fails to increase the life of taps in five to ten times (depending on the composition of the working environment of the pipeline). However, it should be remembered that if the liner is used only in outlets, it should be put radial lining tiles and on the straights, directly adjacent to the taps to completely block the turbulence, which usually extends over a distance of not less than two feet from the end of the bend.