I would like to share these 3 VDO’s demonstrating how Pipe Rams, Variable Bore Rams and Shear Rams work.
This eliminate confusion when the new people in the oilfield read and try to understand about these rams.
Pipe Rams – You will see that the pipe rams will work only on size of the drill string.
Shear Rams – Both rams will be pushed against each other resulting cutting the string of the pipe.
Variable Bore Rams (VBR) – Most of the rigs prefer to use the VBR instead of the fixed pipe rams because its flexibility to work with various pipe size in the wellbore.
You can read more details about the rams preventer via this article -> Ram Preventers as Well Control Equipment
We wish you would enjoy learning this topic.
Well control quiz ebooks here -> 
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Reference book: 
Well Control Books
