The kitchen sink drain pipe is blocked with oil, and what can be used to get through

Find someone who specializes in sewers, you don't have the tools and technology yourself.

After looking at your picture, the problem is very big, friend, the drainage of the kitchen basin needs to be done separately, and it is best to drain it directly independently. In your current situation, you can only change the pipe, change the tee to where the sewer main is connected, and the washing machine is connected to the hose separately. Take the drain pipe of the vegetable washing basin first, be sure to go down diagonally, don't go upside down, cause pressure dropping, and directly buy the sewer pipe connection of the resistance resistance.

It will be fine with a chopstick, and it will be fine with boiling water. (Adopted).

Public plumbing refers to the public use of everyone, your own dedicated part of the house does not belong to the public plumbing, only to the drainage riser belongs to the public part, many people think that they do not see that it does not belong to your home if it is not in your home, that is not right. The sewer pipe is just under the floor slab that you can't see, and all you can see is the downstairs neighbor's sewer pipe.

There is no need to retrofit the main pipe. 1. Leave a section of the branch pipe after the tee connecting the main pipe, and then cut it directly; 2. Insert the basin water hose directly into the inclined tee position; 3. The insertion port is sealed with glass glue. If the branch pipe is higher than the basin trap, you can remove the trap and use the hose below to make the trap function (shape).