posed   of  rugged  components  which  may  be  facilely    5 The  platform   10  comprises  a  self-propelled   hull or manufactured  and  economically  and  reliably produced deck  12 which  serves  to  transport  a  plurality  of  plat-

to  form  a  highly  reliable  long-term  locking  assembly

suitable for use  in an adverse   environment。

BRIEF SUMMARY OF A PREFERRED EMBODIMENT  OF  THE INVENTION

A preferred embodiment of the invention which is intended to accomplish at least some of the foregoing objects comprises a jack-up platform locking apparatus for securing a vertically adjustable leg of an offshore platform with respect to a deck of the platform。 The locking apparatus includes a frame which is operable to be securely connected to the deck of the offshore plat- form。  The  frame  carries  a  locking  assembly  having at

form legs 14 positioned within wells extending through the deck 12。 On location the legs 14 are jacked down- wardly  into engagement  with  the bed  of a body  of wa-

10   ter。 Further jacking  serves to raise the hull  12 above the

surface of the body of water 16 to an elevation sufficient to minimize the tendency of the platform 12 from being contacted by the crest of a statistical storm  wave。

The deck 12 is fitted with the usual accompaniment of offshore drilling and/or production equipment  includ- ing a derrick 18, drawworks 20, piperacks 22, mud processing units 24, etc。 The deck also is provided with crew  quarters  26 and  a heliport  28 as well  as    general

least one tooth compatibly configured with a reciprocal 20 surface on the leg。 The locking assembly is vertically adjustable with respect to the deck and leg through the provision of a hydraulic  motor  positioned  operably between the deck and the lock mechanism。 Horizontal actuation  and  deactuation  of  the  lock  is  provided  by   25

another hydraulic motor which  is operably  connected

between the deck and a back portion  of the lock。 Once the lock is vertically positioned and horizontally en- gaged  a  mechanical  securing  system  firmly  holds  the

purpose cranes 30 and  32。 Each comer  of the  platform

12 is fitted with a vertical well extending through the hull which serves to guidingly receive one of the plat- form legs 14。 Each of the platform legs comprises a plurality of generally vertically extending chords 34 which are structurally tied together and united  by lat- eral bracing 36 which preferably is of the capital “K” or “X”  configuration。

During transportation the legs 14 are carried substan-

tially  above  the  deck  12。  Upon  location  the  legs  are

locking member in a secure  vertical  position。 Finally, the subject invention preferably includes a  locking wedge operable to engage a sloping surface on the back side of the locking member and retain the member in an engaged  posture。

30 jacked through the wells and  into  supporting  contact with the seabed as previously described。 Leg segments,

not shown, may be optionally carried upon the deck during transportation and are lifted onto and aligned with  the upper  end  of the leg segments  14 through   the