PSA sanding disc  stands for prostate specific antigen, which is mainly produced by the epithelial cells of the prostate gland proteolytic enzyme, under normal circumstances, be secreted into the prostatic fluid or semen to the active free form (f-PSA) present in serum the PSA exists mainly in bound form, usually in the f-PSA and complexed PSA and the total PSA (t-PSA) on behalf of serum total PSA levels of serum PSA measurement accuracy is high, stable, reproducible, and is non-invasive helps prostate cancer early diagnosis, monitoring response to treatment and prognosis. Also be used for high-risk groups (men over 50) of prostate cancer screening.
Serum PSA absolutely partly from the prostate, with organ specificity. PSA is a prostate-specific antigen, but not prostate cancer specific antigen, normal and benign prostatic hyperplasia prostate epithelial secretion may PSA, so patients with elevated PSA on the clinical decision-making should be carefully treated differently.

Grinding ring belt  PSA sanding disc  workpiece surface using high-speed operation. Generally on the belt grinder.
Belt around the pressure roller has a certain elasticity and tension wheel by pressing the rotary wheel drive for continuous cutting movement of the workpiece on the conveyor belt or workbench for feed motion when contact with the workpiece under pressure by belt or wheel when the grinding zone, he incurs belt rubbed off the surface layer of material. abrasive belt grinding cutting speed is generally 20 to 30 m / sec, the grinding pressure of 20 to 30 MPa. abrasive belt grinding effectively elimination of the rough surface, but not the grinding grooves and precise corner, suitable for processing flat surfaces and forming surfaces. grinding molding surface (eg turbine blade surface), can be used to match the type of surface of the workpiece molded or shaped contact wheel supporting plate, so that the workpiece between the flexible belt to maintain a uniform contact pressure (Figure 2). dimensional precision grinding belt is generally about 0.02 mm up to 3 m the fine-grained abrasive belt grinding, surface roughness up Ra1.25 ~ 0.16 microns.