METHOD FOR OPENING AND CLOSING UPPER CAP OF REACTOR PRESSURE VESSEL AND SAID REACTOR PRESSURE VESSEL

摘要

PURPOSE:To shorten stages and to prevent sticking by rust by holding a cylindrical body to an upper cap when bolts fixing the upper cap and the cylindrical body are detached from the cylindrical body side and carrying the upper cap to a prescribed position by a hoisting means. CONSTITUTION:The stud bolts 1 are held together with nuts 2 and washers 3 to the upper cap 7 as shown in the figure and this upper cap 7 is carried to the cylindrical body 9 in the case of mounting the upper cap 7 to the cylindrical body 8. Since the upper cap 7 is carried integrally with the stud bolts 1 without particularly removing the individual nuts 2 and the washers 3 and, therefore, the operation for opening and closing the upper cap 7 is extremely facilitated. Since the total number of the stud bolts 1 are removed from the flange 6a of the cylindrical body, the sticking of the bolts 1 and the thickness decrease by the corrosion thereof are averted at the time of water flooding.