Common defects of drum brake pads are: missing corners, side cracks, lining ends Broken hole at the end, bored edge on the inner arc surface, drilled edge on the outer arc surface, source Radial cracks in the rivet holes, paint on the surface (riveted and bonded lining), Surface cracks, markings, molded skin on the inner arc surface (bonding and riveting lining), outside
Molded skin on the surface of the arc (riveted or bonded lining), surface blistering, surface wear scar, Surface pits (surface burrs), surface spots, loose materials, internal surface pits, outer Surface pits, non-special formula self-component spots, high porosity area, inner arc table Automotive brake pad knowledge. The surface of the arc is not flat, the friction table and foreign matter. Figure 6 shows the block at the edge of the hole.