1050. 3(c) 1050. 3(c) holes of the connection and bring them to a snug tight condition. Snug tight is defined as the tightness that exists when the plies of the joint are in firm contact. Use a few impacts of an impact wrench or the full effort of a worker using an ordinary spud wrench to attain the snug tight condition (use the same method that was used for pre- installation verification) . Snug tighten the bolts of the connection by progressing systematically from the most rigid part of the connection to the free edges, and then retighten the bolts in a similar systematic manner as necessary until all bolts are simultaneously snug tight and the connection is fully compacted. Following this initial operation further tighten all bolts in the connection by the applicable amount of rotation specified in Table
tighten the bolts progressing from the most rigid part of the joint to its free edges. 7.e Calibrated -Wrench Tightening. Before the start of bolting operations, perform pre- installation torque calibration as stipulated in PTM No. 429 and as follows : Use calibrated wrench tightening only if installation procedures are calibrated on a daily basis and if a hardened washer is used under the element turned in tightening. Standard torques determined from tables or from formulas, which are assumed to relate torque to tension, are not acceptable. When calibrated wrenches are used for installation, set them to deliver a torque which has been calibrated to produce a tension not less than 5% in excess of the minimum tension specified in Table A. Calibrate the installation procedures at least once each working day for each fastener assembl y rotational - capacity lot combination that is being installed in the work that day . Perform calibration in a device capable of indicating actual bolt tension by tightening three typical fastener assemblies from each rotational -capacity lot, bolts of each diameter, length, and grade, from the bolts being installed and with a hardened washer, from the washers being used in the work, under the element turned in tightening. Recalibrate wrenches if significant difference is noted in the surface co ndition of the bolts, threads, nuts, and washers. Verify during actual installation in the assembled steel work that the wrench adjustment selected by the calibration does not produce a nut or bolt head rotation from snug tight greater than that specified in Table B. If manual torque wrenches are used, turn nuts in the tightening direction while torque is measured. When calibrated wrenches are used to install and tension bolts in a connection, install bolts and nuts, with washers in all