I understand your curiosity, so allow me to explain myself. Many people don't understand the concept of power. Scientifically, this can be measured as work/time.
So for example, if a human moves a 200 pound weight across a certain point in twenty seconds, and a chimpanzee moves the same weight across the same point at four seconds, it would have five times the power of the human in that case.
Now, let me say now that there's just no way to compare any man to an adult chimpanzee, orangutan, or gorilla. An experiment conducted in the Bronx Zoo in 1924 compared the strength of a 165-pound adult man, and a 165-pound male chimp named "Boma", and a 135-pound female chimp named "Suzette".
They compared how much weight the human could pull with one arm to that of the apes, the adult man managed to pull 200 pound before reaching his maximum. The male chimp, on the other hand, pulled 847 pounds of weight with one arm, and the female chimpanzee 1,260 pounds.
So as you can see, are ape relatives simply make the strongest of humans look like wimps. On one occasion, a log fell into the exhibit of an orangutan, one which four or five humans could not even budge after trying to remove it, however when one of the orangutan's was annoyed with its presence, it threw the log out as if it weighed nothing with one arm.
As for the strength of the animals, a chimp in the wild has the strength of 4 to 7 adult men, however generally five adult men..
An orangutan has the strength of 5 to 8 adult men, however generally 7 adult men.
A gorilla has the strength of 9 to 12 adult men, however generally about 11.
These are estimates taken from feats the animals have performed. If you knew the great apes as well as I do, I'm sure you wouldn't doubt it either.
Found this clip on the net! Damn I can only imagine how much force it takes to rip someones hand off. My god!