yes you can do this on a runing trap but make sure that the pipe bore is wide enough!!
Kitchen sink and washer use same drain line. Drain line clogged causing backup of drainage from washer into kitchen sink. Have drain line unclogged to take care of problem. If drain line not clogged, check for proper venting of drain lines.
The drain from the washer to the main line is getting plugged and the floor drain is easier. Drain cleaner in the floor drain should take care of it.
Somewhere down the pipe from where the washer and kitchen drain combine, there is a blockage. You will have to find where these join and look further outward for a 'cleanout' plug, then fit a snake down this plughole.
The drains can get clogged and back up into each other. You can try plunging the drain to clear it, use drain cleaner or call a plumber.
You have a plugged drain on the outside end of the kitchen drain system. -A smart handyman could clear this very quickly.
You can run your discharge pipe from the washer into a laundry tub with the drain put in. After the wash cycle, the water will discharge from the washer into the laundry tub. Keep the water in there and replace the washer discharge pipe back into the usual drain. Let the washer run it's normal cycle. Take the clothes out and put them in the dryer or on the clothes line. The next step is the tricky part. You have to get a pump of some sort to put the discharged soapy water from the laundry tub back into the washer. This water will still be okay to wash the next set of clothes. I would wash the whites first, though. lol
YUP Just make sure there is an air gap in the washing machine
Yes. Unless it is going to a laundry sink (like in a basement) That is how they did it back in the twentys,thirtys and fourtys in oklahoma. There are still alot like that today.
A drain plug washer is not necessary unless you have oil leaking from the drain plug.
Connection of the washer drain hose to the tub drain is very important. This will help prevent leaks for example.
Yes, this is alright as long as the hose from the washer doesn't fit tightly into the pipe. There has to be a little room for air to get in so that the drain will vent.
I am assuming that the question means the water backs up when the washer is used. When the washer drains, it forces a significant amount of water into your pipes in a fairly short period of time. If your pipes are even partially blocked, this large quantity of water can overload the system. However, if this problem occurs at times other than when you do laundry, and there are no other indications of slow or blocked drain lines, I am stumped.