Downhole screen and method of manufacture

A downhole filter assembly, comprising:

• at least two filtering layers having a tubular shape and mounted one over the other and secured to each other without welding;
• a perforated base pipe extending through said layers, said layers having ends extending beyond the perforations in said base pipe and fixedly secured to said base pipe;
• said layers are joined to each other by deformation resulting from an applied force;
• a third layer mounted over said two layers wherein, going outwardly from said base pipe, said layers comprise a coarse filter, a fine filter and a perforated protective jacket, and wherein all of said layers are secured to each other on their ends without welding;
• said fine filter comprises of a sheet of screen material rolled into a tubular shape with ends overlapping by less than about 10°;
• said protective jacket and said coarse filter comprise end rings with said fine filter extending in between;
• said fine filter being squeezed between said rings on both ends to hold the assembly of said filter and protective jacket together.

A method of running in a screen for downhole use, comprising:

• assembling a screen to tubing for running into a wellbore;
• providing said screen from materials that enhance buoyancy as compared to steel construction;
• using said buoyancy to enhance advancement of said screen downhole;
• advancing the screen downhole.