Stabbing Guide Assembly for Dynamic Lifts with Integrated Hydraulic Lift Cylinders, Latching Mechanism, Lift Mandrel, and Bell Nipple Ports
Publication Date: 2015-Mar-05
The IP.com Prior Art Database
To improve the safety, speed, and security of rigging of well servicing equipment on oil or gas wells, particularly when dynamic lifts are involved. The invention provides a number of features combined into a single unit: a stabbing guide which assist locating the equipment; a spacing length that allows some heave to occur without losing control of the lift; integration with a lift mandrel to simplify rigging and reduce the number of lifts required; short-stroke hydraulic lift cylinders used when rigging up and rigging down to ensure nothing is hung up before attaching the crane; an integrated locking mechanism to eliminate the need align and bolt up flanges; and a fluid port to allow the unit to be used as a bell nipple. In addition the invention is fully rated to handle high imposed loads from equipment such as Hydraulic WorkOver (HWO) units or Coiled Tubing (CT) units. This invention, therefore, provides an integration of features that working together reduce the time, height, and risks of rigging up well servicing equipment, much more so than if the features are applied separately.
The invention consists of three primary components – a housing (1), a stabbing prong (2), and a lift mandrel (3).
The housing (1) provides a receptacle for the stabbing prong (2), and locking bolts (4) to secure the stabbing prong in the housing. Mounted on the housing are a number of hydraulic cylinders (5) that are arranged and situated to allow lifting of service equipment off of the housing without the use of a crane. When the locking bolts (4) are withdrawn, effectively unlatching the stabbing prong, the cylinders (5) are extended by several inches to lift the stabbing prong thereby ensuring that the stabbing prong (2), and anything else that might be attached thereto, will lift freely and is not hung up. The bottom of the housing is provided with a connecting means (6) (typically an API flange, or clamp hub) to provide a secure mechanical and leak sealed (but non-pressurized) connection to what would typically be a stack of pressure control equipment. The top end of the housing (7) provides a cone surface that reduces the accuracy needed to align the stabbing prong with the housing, and also provides landing surface for the flange of the stabbing prong. One or more fluid ports (8) with connection flanges or hubs (9) are provided on the housing so that any fluids rising from below will flow out through the port, behaving functionally like what is commonly referred to as a “bell nipple” which saves space and reduces the total rig-up height. The housing must withstand the loads imposed by the well servicing equipment mounted above, where such loads can typically range from less than 100,000 lbs to over 500,000 lbs in tension or compression, depending on the application. Different size and/or load capacity housings (and associated stabbing prongs) can be designed and made available.
The stabbing prong (2) is attached to the bottom of the well servicing equipment (9), typically via flange, clamp or other means that provides a structurally sound connection that can withstand the applied forces and moments. The prong‘s internal diameter can be designed large enough to allow passage of tubular products or tools as is necessary in general for well servicing type work. The prong’s bottom end is tapered to help align and slide the prong into the housing. The prong’s length is a function of the design maximum heave allowance (roughly 5 feet) and this must match the available length inside the housing to allow the lifted equipment to ride up and down through the heave without impact or otherwise losing control of t...