Fire and a fatality following the ejection of a gland nut and lockscrew assembly from a wellhead while under pressure shortly before starting tubing installation has highlighted the need to ensure manufacturers procedures are always followed suggests a safety alert from the International Association of Oil and Gas Producers.
Lockscrews are commonly used in surface wellhead equipment to mechanically energize or retain internal wellhead components. Lockscrews are not standardized across the industry, so manufacturers’ procedures should always be used for operations that may require manipulation of lockscrews. Work involving gland nut and lockscrew assemblies should be done under the supervision of qualified service personnel from the wellhead equipment provider who have access to the operational procedures, key dimensions, and torque ratings necessary for correct use.
Operators should consider working with their wellhead equipment and service providers to validate the integrity of gland nut and lockscrew assemblies that are exposed to wellbore pressure in the field by taking the following steps: