strength of weld usually refers to tensil strenth of the weld. e.g- a 60 series rod will have 60,000 lbs tensil strength per cubic inch. a 70 series rod, 70.000 lbs. there is also the type of metal , and dozens of other factors that has to be considered along and many other factors. thats why they make hundreds of types of rods.
__________________
"Did you get my e-mail?" - "The biggest problem in communication is the illusion that it has taken place" - George Bernard Shaw, 1856