Which country? In the US, you need a Class A CDL without a "no tractor-trailer" restriction, and without an air brake restriction. In Canada, it's a Class 1 licence. In the United Kingdom, it's an E+C licence. In South Africa, it's an EC licence. In all instances, you're better off to just attend a truck driving school.
For a regular five axle unit without oversize/overweight permits, 23 to 25 tons.
The tractor weighs 20,000 pounds, the trailer weighs whatever it weighs, and the maximum weight of a loaded tractor trailer with one trailer is 80,000 pounds.
tractor trailer
I would have to say no. I have a tractor that is insured the only thing that is insured is just that the tractor (fire theft etc). Although You can get your trailer insured just as you can an ATV horse trailer car truck if you had a policy for it. your tractor insurance will not help with the trailer.
semi truck, or semi tractor trailer, and 18 wheeler.
Depends on what type of tractor and trailer you had in mind. For a farm tractor pulling a trailer, it's usually a pintle on the tractor which is run through a clevice on the trailer. For road going vehicles, the fifth wheel trailers are often used, where a trailer kingpin will be inserted and locked into a fifth wheel on the vehicle. In the case of an 18 wheeler, air lines will connect from the tractor to the trailer to operate the trailer's air brake system.
Semi or Tractor Trailer-semi.
The weight that can be carried in a semi trailer legally varies. It depends on how much the tractor pulling the trailer weighs. The maximum weight of the total unit, truck and trailer is limited at 80,000 lbs without getting special permits. For a heavy tractor, the trailer would have to be loaded with less weight than a trailer pulled with a light tractor. It's not uncommon for a trailer to comfortably carry 45,000 with most over the road tractors. Some trailers can be loaded heavier as long as the don't exceed the maximum. Also, I should mention, axle weight will affect how much can be loaded also. only 34,000 can be loaded on the trailer and tractor rear axles. This means that the weight on the trailers must be properly distributed.
An 18 wheeler consists of a tractor (meaning something that pulls) and a trailer (meaning something that follows.) A semi tractor-trailer rig has a trailer that sits on top of the frame of the tractor on a coupling device called a "fifth wheel." The tractor has ten wheels with two on the front axle and four on each drive axle in the rear. The trailer has two axles with 4 wheels each. The tractor and trailer together are informally called a rig. Is that what you were after?
this is a standard trailer pulled behind a tractor truck wiyj8 wheels at the back of the unit
The most common brakes on a tractor trailer are the s-cam brakes
That would be a tractor and trailer that has a total of 18 wheels, 10 on the tractor and 8 on the trailer.