高中压外缸是600MW汽轮机组的重要铸钢件之一,属于压力容器部件,技术要求很高。除需具有良好的综合机械性能(包括常温及高温状态下的性能)外,还要对其全部表面进行磁粉探伤和内部的超声波探伤。对外缸的尺寸公差要求严格,必须符合JB-2580-79二级精度铸件的规定。为达到上述要求,确保试制成功,外缸的热处理是关键环节之一。 High pressure cylinder is one of the important steel castings of 600MW steam turbine unit, belonging to the pressure vessel components, high technical requirements. In addition to having a good overall mechanical properties (including room temperature and high temperature performance), but also its entire surface of the magnetic particle testing and internal ultrasonic flaw detection. External cylinder size tolerances demanding, must comply with JB-2580-79 two precision casting requirements. In order to achieve the above requirements, to ensure trial success, the outer cylinder heat treatment is one of the key areas.