Question About Snatch Block

[2BLUE]

I currently have 3 1/2 inch snatch block.

I also own a 6 inch snatch block

Now using a snatch block doubles your pulling power....of your winch.

How do I figure out the mathematics on the difference between snatch blocks?

[AndyL]

No diffence - rated to wll on tag. But the 3" would be for a small winch - like 2000lbs - there's a math formula, based on rope diameter to shiv diameter - 3½" would be for ¼" cable or thereabouts, 5/16" like most 8000lb+ would need a 5"+ shiv.

But there is no way to calculate - its on the tag or stamped in. If its not its trash.

[CelicaST-162]

I'm not sure about the particulars number wise. However, a heads up. A pulley, or commonly referred "Snatch block" doesn't actually double the winches pulling power. A pulley (Snatch Block) reduces the load the winch thus giving it the mechanical advantage.

[Black Gts]

It doubles the capacity of your line, or 3x etc. Also reduces stress greatly on winch.

[BerserkerCatSplat]

Originally posted by CelicaST-162
I'm not sure about the particulars number wise. However, a heads up. A pulley, or commonly referred "Snatch block" doesn't actually double the winches pulling power. A pulley (Snatch Block) reduces the load the winch thus giving it the mechanical advantage.

How does a snatch block not double the force applied to the pulled object for a given force exerted by the winch? That's usually referred to as "pulling power".

[2BLUE]

Well my RZR pulled out a 5 ton on the weekend stuck in waprious using 2 snatch blocks the rzr tied to a tree. It was crazy to see!!

[Thales of Miletus]

Originally posted by BerserkerCatSplat


How does a snatch block not double the force applied to the pulled object for a given force exerted by the winch? That's usually referred to as "pulling power".

Friction of the block. Usually times 4% per sheave.

You should always use the desirable minimum diameter and not the critical minimum when making a pull.

The formula I use for wire rope strength is diameter squared times 40T divided by a safe working factor of 5. Add 10% for wire core.

1/2 x 1/2 x 40 = 10 tons / 5 = 2 tons