炉壁内表涂以高反射率涂料后，可明显缩短工件随炉升温时间，但不能减少空炉升温时间；

If the refractory wall is covered with high reflectivity coating, the heating-up time with workpieces is reduced obviously, whereas the heating-up time at empty cannot be reduced;

youdao

炉壁内表涂以高反射率涂料后，可明显缩短工件随炉升温时间，但不能减少空炉升温时间；

If the refractory wall is covered with high reflectivity coating, the heating-up time with workpieces is reduced obviously, whereas the heating-up time at empty cannot be reduced;

youdao