Compressor having a lower frame and a method of manufacturing the same

A compressor, comprising:

• a cylindrical shell;
• a rotational shaft rotatably mounted in the cylindrical shell;
• a rotor and stator configured to rotate the rotational shaft;
• a compression device driven by the rotational shaft;
• a lower bearing rotatably supporting one side of the rotational shaft;
• a lower frame supporting the lower bearing, the lower frame press-fitted into a lower end portion of the cylindrical shell;
• wherein the lower frame includes:
• a main body press-fitted onto an inner circumferential surface of the cylindrical shell;
• and
• a flange that extends from the main body, the flange limiting a press-fit depth by contacting the lower end portion of the cylindrical shell, and a base sealing the lower end portion of the cylindrical shell, wherein a mounting portion is formed on the base to mount the flange, wherein the mounting portion includes a mounting surface that contacts a lower surface of the flange and an annular wall, wherein an entire outer circumferential surface of the flange is spaced apart from an inner circumferential surface of the annular wall, and an outer circumferential surface of the shell, which is placed on the flange, is spaced apart from the inner circumferential surface of the annular wall, and wherein the welding is formed at a portion defined by the outer circumferential surface of the flange, the outer circumferential surface of the shell, and the inner circumferential surface of the annular wall facing the outer circumferential surface of the flange and the outer circumferential surface of the shell.