BACKGROUND OF THE INVENTION This invention relates to a jack-up platform locking 5 apparatus。 More specifically this invention relates to an apparatus for locking an offshore platform deck with respect to a vertically adjustable leg ot the platforiri independently of a platform jack-up drive assembly。82310
In the past, offshore platforms or towers have been extensively utilized around and upon the continental shelf regions of the world。 Examples of offshore plat- form installations include supports for radar stations, light beacons, scientific and exploration laboratories,
chemical plants, power generating plants, etc。 Princi- 15
pally, however, offshore platforms have been utilized by the oil and gas industry in connection with oil and gas drilling, production and/or distribution operations。
In conducting such offshore activity several platform designs have been utilized in the industry。 In deep water 20 applications, semi-submersible or floating drill ships
which are dynamically positioned and/or turret moored over a well site have been effectively utilized。 In shal- lower water applications fixed length towers have been fabricated on shore and either transported in a horizon- 25 tal posture to an offshore site by barge or towed upon bouyancy chambers within the tower legs。 On site the tower is pivoted into an upright posture and the base of
the tower legs are positioned into firm engagement with
gree of undesireable slack or vertical mobility between
the legs and platform。 Such mobility may prove to be disadvantageous when the platform encounters envi- ronmental hydrodynamic and aerodynamic loading。 More specifically platform legs typically comprise a set of three or more vertical chords which are intercon- nected and strengthened with “K” or “X” type bracing。 As previously mentioned the legs extend through wells fashioned within the platform deck and peripherally pass adjacent bearing surfaces at the upper and lower surface of the deck。 Tolerance within some jack-up mechanisms, combined with bending moments encoun- tered from environmental loading, tends to displace the legs into abutting lateral contact with the upper and lower surfaces of the deck。 Accordingly typical plat- form legs must be overdesigned to carry lateral reaction forces at locations intermediate the junctions of the “K” or “X” type bracing。
In a similar vein present jack-up systems are fabri- cated with large structural members in order to with- stand and react against environmentally imposed mo- ments。 The structural size of these members needed to safely react peak statistical moments adds a consider- able degree of dead weight and cost to the overall plat- form design。
The difficulties suggested in the preceding are not intended to be exhaustive, but rather among many which may tend to reduce the effectiveness and owner satisfaction of prior jack-up offshore platform systems。
the seabed。 A platform deck is then fabricated upon the 30 Other noteworthy problems may also exist; however,
erected tower for conducting offshore operations。 Such
fixed platforms require considerable time to assemble and once in position are difficult to relocate。
One platform design which combines many of the advantages of floating and fixed equipment is known as a “jack-up platform”。 In this connection a barge or self-propelled deck, operable to function in a conven- tional flotation capacity during transportation, is fitted with extendable legs which are deployable on site。 More specifically, the hull/deck carrying one or more jack-up legs is either towed or navigated to a desired offshore site and the legs are jacked through wells in the deck into firm supporting engagement with the water bed。 Further jacking serves to raise the deck with re- 自升式平台锁定装置英文文献和中文翻译:http://www.youerw.com/fanyi/lunwen_96548.html