公交车挺进朋友人妻的身体里,在车后座肉同事人妻,粗大挺进朋友的未婚妻

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    7 selection techniques of wheel hardness

    2014-06-28 295

    Abrasive hardness refers to the degree of difficulty of grinding wheel in the grinding force was dropping on the surface, how to select the grinding wheel hardness, small make up here to tell you.
    1 grinding soft materials to choose grinding hard, grinding hard materials should choose soft grinding wheel;
    2 cooling liquid grinding dry grinding wheel hardness and high 1~2 level;
    3 grinding soft and toughness of non-ferrous metal, hardness should be too soft;
    4 the end mill grinding wheel hardness than the circumference, should choose soft;
    5 in the grinding under the same conditions, to a high of 1~2 small grade resin bond wheel than vitrified bond grinding wheel hardness;
    6 grinding poor thermal conductivity material should be soft grinding wheel;
    7 wheel rotation speed is high, the grinding wheel hardness optional soft 1~2 level.

    公交车挺进朋友人妻的身体里,在车后座肉同事人妻,粗大挺进朋友的未婚妻