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| Proforma Safety, LLC Proforma PSI…when performance counts. Vertical Pig Door Fails During Commissioning In Azerbaijan recently a door mechanism failed on a water injection vertical pig launcher while integrity testing was being conducted during commissioning. Twenty minutes into the holding period the closure mechanism failed, releasing a jet of high pressure water vertically. Minutes prior to the failure, the door had been observed with a slight weep through the drain point. The four locating pins in the side of the door were found to be damaged, with a maximum protrusion of approx. 0.5mm versus a specification of 2.5mm. Two of the pins were also sunk into the door, thus allowing the door to be installed hard-up against the hub on one side of the closure. Positioning the door off center created a band segment vertical gap of 5.4mm versus specified tolerance of 2.7-3.2mm on the side diagonally opposite the locking segment and PWS. The door was therefore not fitted properly within the chamber, creating a sealing gap on one side of the unit. Vendor documentation did not highlight -- nor did operations and maintenance staff fully understand -- the purpose of the locating pins, or that it was critical the door should be square. In addition, if the door and pins had been inspected after installation, the risk of failure would have been identified. As it was, no post installation inspection or assurance check was conducted. Lessons learned included the need for
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