Question about screw compressors

The screw has mechanisms for injecting oil and water; what you’re referring to is probably a mixture of oil and gas

In a screw compressor that requires oiling, where is the location for adding oil?

The oil-injected compressors I’m referring to are those in which oil enters together with the material and mixes inside the male and female rotors; however, such compressors also have their issues, for example at the slide valve area

1. There is an oil-gas separator at the outlet of the screw compressor; where does the oil come from? Has the isolation nitrogen for the dry gas seal failed? Answer: Screw compressors are generally divided into dry-type and wet-type. Wet-type compressors are further divided into oil-injected screw compressors and liquid-injected (usually water) screw compressors. Based on the description provided by the forum owner, it should be an oil-injected screw compressor. Oil is sprayed into the compressor chamber for sealing, lubrication, and cooling; it is discharged along with the gas compressed by the compressor and has no direct relation to the dry gas seal. 2. Where are the lubrication oil injection points for screw compressors? Answer: Lubricant is generally applied at bearings, and in screw compressors with liquid injection, it is also added to the sealing chamber to protect the seals. 3. What type of dry gas seal is generally used in screw compressors? Is it also of the series or double-face type? Answer: This should be determined based on the process parameters, characteristics of the medium, and on-site utility conditions.

Thank you; mainly, I haven’t seen the specific structure inside, so I can’t quite figure it out. Isn’t the bearing area separated from the compressor’s working chamber by nitrogen to isolate it? Is the lubricating oil then injected directly into the working chamber? And that slide valve is usually its outlet valve, right?

I’ve figured out what I was wondering about just now. There’s another question: the documentation states that wet screw compressors use synchronization without gears. What does that mean? How can the rotor move without gears? Also, can I understand the slide valve as a valve whose outlet allows for adjusting the air flow rate?

First question: Dry and wet screw compressors differ in the way in which the male and female rotors transmit power. In wet screw compressors, the gap between the male and female rotors is very small; the male rotor drives the female rotor to rotate through the medium present in the chamber, such as lubricating oil or water ； In dry screw compressors, the male rotor drives the female rotor to rotate through synchronous gears. Second question: The slide valve is primarily used to adjust the effective working length of the rotor in a screw compressor, and it allows for control over the air volume delivered by the screw compressor.

Simply put, it’s compression with oil involved; of course, there is oil present