有关SPC控制图常数和GRR的K值系数控制图常数GRRK值系数nX界限系数A2R下限系数D3D2R上限系数D4测量次数n测量次数K1测量人数K2产品数K321.88003.26724.563.653.6531.02302.57533.042.702.7040.72902.82842.502.302.3050.57702.11552.212.082.0860.48302.0046001.9370.4190.0761.9247001.8280.3730.3161.8648001.7490.3370.1841.8169001.67100.3080223177110001.621