Power at Work: So there is such a thing as a Grade 12 bolt

An update on bolt grades, prompted by an observant reader


After my first article on bolt grading appeared in the December 2008 issue of Better Farming, the phone rang. An observant and knowledgeable reader assured me – very politely, I might add – that I had shortchanged you.

I had said that Grade 8 was the highest grade of bolt available in the imperial system. He assured me that, indeed, a Grade 12 is also available. When I inquired about the use and source, he told me that he regularly uses Grade 12 bolts to attach the bars to the feeder house chains in his combine.

The use of bolts allows him to change damaged bars without removing the feeder house chain.

Better Farming - JuneJuly 2009