IPE-EP-5-5-4

IPE Engineering Practice IPE-EP-5-5-4

Document number: IPE-EP-5-5-4 · Section: 5 — Piping

CoInafsletcatilo nA Prouinbta E nEgningeeirninege Prriancgtic Pesractices Bolting Procedures for Flanged Connections 12.4 A log of the measurements taken for the initial lengths and any subsequent elongations shall be recorded and provided to the Owner’s Engineer. The installation record given in EP 5–5–4R shall be used to record ultrasonic measurements. 12.5 For the second to last torquing/tensioning setting, the elongation shall be checked to determine if the final torque or tension setting is appropriate. Adjustments to the final setting may be required depending on the elongations measured. 12.6 A minimum of 25% of the bolts shall be checked after final loading for each joint that is to be ultrasonically controlled. When only a sampling (25%) of the bolts are measured, they shall be chosen from the same quadrant on the flange (eg. bolts #1,13, 5,17, 9 from Figure 4). 12.7 (*)The acceptance criteria for final elongation measurements shall be ” 15% of the targeted elongation, unless otherwise specified by the Owner’s Engineer. If the average measured value is close to the targeted value but the scatter is not within the ” 15% limit, additional passes are required at the same load setting. 12.8 (*)The Owner’s Engineer or Inspector shall sign off on the Data Sheet to show acceptance of the joint. 12.9 (*)When many flanged joints are being bolted up as is the case during turnarounds, ultrasonic measurement can be eliminated on some joints provided previous joints of similar bolt diameter and design have been accepted using ultrasonic control and established bolting procedures, and approval is given by the Owner’s Engineer. 12.10 All measurements from the bolt gauge shall be repeatable. A number of readings shall be taken showing consistent values before entering them on to the Data Sheet. 12.11 Bolt gauges shall be calibrated before each new application by an experienced operator. 13.0 USE OF CONTRACTORS TO PROVIDE BOLTING SERVICES 13.1 The use of contractors that specialize in providing bolting services is strongly recommended during shutdowns when a large number of joints are being assembled. 13.2 (*)Contractors providing bolting services should be hired directly through the Owner. Subcontracting these services through other maintenance contractors is not recommended. If bolting contractors are not hired by the Owner, the Owner’s approval of the sub–contractor is required. 13.3 Contractors providing bolting services should be given authority to monitor all aspects of the joint assembly. Their functions can include but are not limited to the following: 1) Monitor and advise on bolt and flange preparation. 2) Coordination with Owner’s Inspector for approval. 3) Provision of hydraulic torquing and tensioning equipment. 4) Provide maintenance people to perform final assembly of the flanged joints. 5) Monitor and advise the Owner’s maintenance forces during joint assembly. 6) Provide ultrasonic elongation measurement and control. 13.4 Supervisors provided by bolt contractors shall be limited to supervising a maximum of three bolting crews. If equipment probes, or any other problems, require a majority of a supervisor’s time, additional supervision shall be provided by the contractor.

CoInafsletcatilo nA Prouinbta E nEgningeeirninege Prriancgtic Pesractices Bolting Procedures for Flanged Connections 14.4.7 (*)Cold cutting of seized fasteners is permissible. No burning shall be allowed on hydrocarbon lines during Hot Bolting procedures. Burning shall not be allowed during Half Bolting procedures unless approved by the Owner’s Engineer.

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