API RP 7HU1-2009 pdf free download

API RP 7HU1-2009 pdf free download.Safe Use of 2-inch Hammer Unions for Oilfield Applications.
1 Scope 1.1 General This recommended practice (RP) sets forth procedural recommendations as well as an engineering solution to the mismatching of a female 2-inch Figure 402, a female 2-inch Figure 602, or a female 2-inch Figure 1002 hammer union component (sub) with a male 2-inch Figure 1502 hammer union component (wing nut) as described in 3.2. The procedural recommendations described in this RP should be implemented to reduce further incidents. The engineering solution, which prevents the mating of female 2-inch Figure 402, 2-inch Figure 602 and/or 2-inch Figure 1002 subs with the wing nut of the 2-inch Figure 1502 hammer union, applies to the manufacture of new hammer union components and should not be applied in the modification of existing hammer union components due to unknown factors caused by field wear. 1.2 Objective The objectives of this RP are as follows. a) Raise awareness of the incompatibility of these hammer union components, whereby these components will mate improperly when threaded together; and are likely to fail explosively below the rated working pressure of the hammer union parts (male or female). b) Describe a recommended procedural solution to the industry that will reduce the likelihood of a 2-inch Figure 402, 2-inch Figure 602 and/or 2-inch Figure 1002 hammer union component being made-up inadvertently to a 2-inch Figure 1502 hammer union component. This procedural solution is critical because, depending on industry acceptance and implementation, the engineering solution might take years to effectively eliminate industry equipment manufactured to the original design of 2-inch Figure 402, Figure 602, and Figure 1002 hammer union components. c) Advise users and suppliers of hammer unions to adopt those procedural recommendations that are reasonably practicable to implement. NOTE The recommendations in this document build on advice and advisories previously communicated to the industry.2.1.1 failure Mechanical separation of the female/male union components, especially under pressure, such that the equipment no longer is able to perform in the manner intended. 2.1.2 figure number A designation used by manufacturers of hammer union components to indicate the general design characteristics. NOTE Depending on the manufacturer and specific design, figure number may represent pressure rating, specific geometric configuration of a union (e.g. flat-faced, misaligning, etc.), electrical insulating capability, etc. of the union type and its components. 2.1.3 incompatible Hammer union components that have the same nominal size, but different pressure ratings, materials and/or geometry. 2.1.4 inspection Comparison of equipment conformity to predetermined standards, followed by a determination of action required, if any. 2.1.5 maintenance Actions to include adjustments, cleaning, lubrication, and replacement of consumable components, as necessary to maintain the serviceability of the equipment. 2.1.6 manufacturer Individuals or companies manufacturing (or who have manufactured) equipment or materials covered by this RP. 2.1.7 mismatch Connecting hammer union components that have the same nominal size, but different pressure ratings, material and/ or incompatible geometry. 2.1.8 testing Actions that are carried out on a piece of equipment to determine if that equipment can perform its intended function. 2.1.9 users Individuals or companies responsible for the use of equipment or material, or implementing recommended practices. 2.1.10 walk-the-lines The activity of checking the equipment directing the flow of fluid (from high pressure to low pressure) along each branch of the process ensuring that each item of equipment is suitably rated and matched to the physical and environmental conditions to which it is exposed by the operations.
3.2 Example of the Hazard The mismatching of either the female 2-inch Figure 402, female 2-inch Figure 602 or the female 2-inch Figure 1002 hammer union component (sub) with a male 2-inch Figure 1502 hammer union component (wing nut) is a worldwide issue in the industry and can cause serious incidents, including fatalities. Complete and proper make-up of hammer union components is required to attain the rated working pressure of the equipment. The root cause of the mismatch is that the 2-inch Figure 402, 2-inch Figure 602 and 2-inch Figure 1002 unions were designed with the same thread pitch as the 2-inch Figure 1502 and the female subs have a major (external) thread diameter that is just large enough to engage the minor (internal) diameter of the 2-inch Figure 1502 wing nut internal acme thread. Consequently, although these mismatched hammer union components (2-inch Figure 1502 wing nut with a 2-inch Figure 402, Figure 602 or Figure 1002 female sub) may fully make-up and hold some level of pressure, an explosive failure of the mismatched unions will occur well below the rated working pressure of any of the components, putting people and property at risk.