Understanding Plow Bolts

Differentiating Between Plow Bolts

This week in First Year In Fasteners is all about Plow Bolts! I know some readers might think, it’s almost spring…shouldn’t we have covered this back in the fall? Well, we in the fastener industry know there’s more to plow bolts than just snow (or at least now I do).

“Plow Bolts” is actually a pretty generic term and their use depends on the industry. When someone says “I need a plow bolt,” they could be referring to the bolt that holds a blade onto a snow plow. But if someone with a pickup truck with a plow attached asked for one, more often than not they mean “carriage bolt” which is more common for smaller equipment. The most common applications for plow bolts we see for our customers at Earnest are winter equipment, construction, and agriculture.

There are different styles of Plow Bolts and because of that, they’re numbered from 1-11 (insert Spinal Tap reference here), but the numbers actually don’t mean much. For example, #1 doesn’t mean that bolt is the #1 best Plow Bolt ever. They’re just there to differentiate between styles.

#3 Plow Bolts are the most popular likely because Caterpillar designated them to be their standard, and when a powerhouse like CAT says that, others are likely to follow. It’s deeper than that though; #3 Plow Bolts also have a domed head, which is ideal for snow plows. If you have a bolt with a domed head, it can handle more wear. Because the blade is the more expensive part, you want the bolt to take more of the wear and tear.

#7 Plow Bolts are our second most popular Plow Bolt. You’ll see these more on bucket tooth excavators to scoop dirt. Those excavators have teeth on the bucket to break through dirt, and they’re fastened to the bucket using #7 Plow Bolts. The scooping functionality on dirt rather than pushing on concrete means a domed head plow bolt isn’t necessary.

At Earnest, we stock #3, #7, and Clipped Head Plow Bolts in a plain finish (there’s usually no need to plate something that’s going to get a lot of wear and tear!) So what about Plow Bolts 1, 2, 4, 5, 6, 8, 9, 10, and 11? Well, #1 and #2 were used by companies that no longer exist. #4 and #6 are still in the IFI specification book, but Earnest doesn’t stock them. Do you know of any applications for the other Plow Bolts? Sign into your web account and comment below!

Did you know not all plow bolts (and fasteners in general) are created equally? You can learn how to spot quality differences with our Spotting Quality white paper.