机电技术专业英语 教学课件 作者 徐起贺 张庆良pata a lesson Twenty.pptVIP

* 机电技术专业英语 Lesson Twenty Text Safety Notes for CNC Machine Operations Safety is always a major concern in a metalcutting Operation. CNC equipment is automated and very fast, and consequently it is a source of hazards. The hazards have to be located and the personnel must be aware of them in order to prevent injuries and damage to the equipment. Main potential hazards include: rotating parts, such as the spindle, the tool in the spindle, chuck, part in the chuck, and the turret with the tools and rotating clamping devices; movable parts, such as the machining center table, lathe slides, tailstock center, and tool carousel; errors in the program such as improper use of the G00 code in conjunction with the wrong coordinate value, which can generate an unexpected rapid motion; an error in setting or changing the offset value, which can result in a collision of the tool with the part or the machine; and a hazardous action of the machine caused by unqualified changes in a proven program. Safety and Maintenance for CNC Machine Lesson Twenty Daily Maintenance 1. Checking the External View （1）Machine oil (cutting oil, lubrication oil) has been scattered onto the servomotor detector or main unit of the NC, or is leaking; （2）Damage is found on the cables of the movable blocks, or the cables are twisted; （3）Filter clogging; （4）A door of the control panel is not open; （5）Ambient vibration. 2. Checking the Inside of the Control Unit Check that the following troubles have been eliminated: （1） Cable connectors are loosened; （2） Installing screws are loosened; （3） Attachment amplifier screws are loosened; （4） The cooling fan operates abnormally; （5） Cable damage. Lesson Twenty Fault Diagnosis and Action When a running fault occurs, examine the correct cause to take proper action. To do this, execute the checks below: Checking the Fault Occurrence Status 1. Check the following: （1） When did the fault oc