I want to ask my coworkers to take my place on the assembly line so I could sit down.
What is your reason for feeling the need to sit down anyway?
I just do not feel like working this entire afternoon. I would rather take it easy instead.
You are at work so that you can work. Asking others to do your work for you is a dereliction of your duties. Do what you have contracted to do and don't lean on others.
It's my job to work, not sit their faking trying to work. I'll just call a manager to complain about this.
I agree. Asking your coworkers to do the work you are suppose to do is not going to go over well with them or the manager. You are better off pushing through until the end of the workday just like your coworkers most likely have to do.