Question about force and pulleys

[Fishuhalik]

So I work in the oil & gas field. My job is running a variety of tools in the well on a braided cable with an insulted copper core that can perform a variety of tasks. We've been debating this for a while now and I'm wondering if anyone can give me the scientific theory for why I'm right (or wrong!)

The wireline has a breaking strength of +/- 10,000lbs of pulling force. If (as illustrated in the poorly drawn picture below) one of our tools is stuck in the well, how much force is being applied to the wireline at the top pulley (words circles with arrows pointing to it) and the line going from the top pulley to the stuck tool (words also circled). Any help would be tremendously appreciated!!

 

http://s31.photobucket.com/user/fishuhalik/media/CBD71CD0-962F-4054-B4AC-2780F9D0E9DE_zps9it3ndul.jpg.html

I should add. My coworkers are saying that the force applied to the line where it goes through the top pulley is doubled, effectively 6,000lbs of force being applied to the wireline. I know that the force put on the top pulley shackle is doubled, but they're saying the force being applied to the wireline where it goes through that top pulley is also doubled

Also, all of us but one agree that the force applied to the line going from the top pulley to the stuck tool is 3,000lbs. He's saying the force is doubled on that part of the line also.

Thanks for any help!

[studiot]

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[Acme]

I'd say the force on the tool is only 3,000lbs and that the upper pulley and the low pulley behind the truck only change the direction of the force. If the setup was doubling the force then it would be halving the distance traveled by the tool, i.e. for every 1 foot taken up on the truck reel the tool would move only 6 inches. (Disregarding stretch in the line of course.)

 

Explanation of pulleys: Pulleys