necessary to tighten and torque each bolt 50 to the desired tightness or conversely when desired to loosen and disengage the bolts and nuts with respect to the foregoing suitable wires not shown may be inserted through the respective holes 16a 18a in the plate portions 16 18 so as to interconnect the retainer members 10 with each other and or secure the retainer members to the structures or flanges on which they are mounted the foregoing enables a rapid and labor saving procedure by a pipefitter in the assembling and fastening or disassembling of flanges of suitable piping or reactor installations for example such as hydrotreater reactors diverse chemical reactors petrochemical manufacturing facilities and other process installations possessing extensive and numerous nut and bolt fastener arrangements which may advantageously employ the inventive nut retainer members and also including thermal process installations employed for thermal cracking visbraking fluid coking delayed coking catalytic cracking catalytic reforming catalytic hydrocracking catalytic hydrorefining alkylation aromatics isomerization units and hydrogen manufacturing installations among many other installations of all types accordingly the quantitative and physical applications and uses of retainer members 10 of this type are practically unlimited in the most diverse technologies moreover the retainer may be made in various suitable sizes both individually or in complete sets and with commensurate bolt circle radii and spacings between the respective nut receiving apertures the latter of which may be designed to house different nut sizes so as to be adaptable to various.