Abstract:
An improvement in a side element of a drilling template for wells at sea for extracting hydrocarbons, wherein the side element is connected to a central section of the drilling template and projects horizontally out therefrom. The side element is arranged to carry equipment of various types. According to the invention the side element comprises a coupling section for releasable connection with a coupling section of the equipment.

Description:
BACKGROUND OF THE INVENTION 
     The invention relates to an improvement in a side element of a drilling template for wells at sea. 
     DESCRIPTION OF THE RELATED ART 
     From e.g., GB 2 285 274 (corresponding to Norwegian patent application no. 944545) it is known that a drilling template can be lowered from a platform at sea to a mooring device on the seabed by means of guidelines, which extend from the platform to the mooring device. To the sides of a central section of the drilling template there are hinged via hinge pins which are attached to the central section a number of side or wing elements which can be tilted from a first position, wherein they extend vertically upwards from the hinge axis to a second position or operating position, wherein they extend horizontally outwards from the central section. In the first or upwardly tilted position the drilling template&#39;s diameter measured in a horizontal plane is minimal, thus enabling the drilling template to be lowered through a moon pool of the platform. When the drilling template has been installed on the seabed, the side elements can be tilted down to the operating position. Each side element carries equipment for a specific purpose. If equipment is required for another purpose when using a side element, the side element can be removed by unhooking it from its hinge pin. The side element can then be raised to the platform, by guiding it by the guidelines, whereupon another side element can be lowered to the drilling template and hooked on to the hinge pin. 
     When using a drilling template which is arranged to be lowered to the mooring device without the use of guidelines, as described in applications submitted simultaneously with this application, however, it may be difficult to hook on the side element since there is little room between other pieces of equipment on the drilling template and the hooks which have to be attached to the hinge pin are small. 
     SUMMARY OF THE INVENTION 
     The object of the invention, therefore, is to provide a device of the above-mentioned type which is not encumbered with the above-mentioned disadvantages. 
    
    
     The invention will now be described in more detail with reference to the drawing which schematically illustrates embodiments of the device according to the invention. 
     FIG. 1 is a side view of a first embodiment of a side element of a drilling template. 
     FIG. 2 is a perspective view of a second embodiment of a side element. 
     FIGS. 3-9 are side views on different scales of adapters for various applications of the side element. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     With reference to the drawing, the direction indication “up” should be understood as the direction towards the edge of the drawing facing away from the reader. 
     The side element  1  which is illustrated in FIG. 1 is located in the second, downwardly tilted position and comprises a hinge section  2  which is provided at one end of the side element, and which may comprise flanges  4  with mutually coaxial, through-going holes through which there extends a hinge pin  6 . The side element  1  is linked to the central section of a drilling template (not shown), the central section having a supporting section which is connected with the flanges  4  via the hinge pin  6 , which also extends through holes in this supporting section. 
     At a distance from the hinge pin  6  the hinge section has a contact section  8  with a contact surface  10  which is arranged for abutment against a corresponding contact section (not shown) of the drilling template&#39;s central section, with the result that forces which are exerted against the hinge pin  6  and the contact section  8  create a reactive power moment which counteracts the static moment about the hinge pin axis as a result of the weight of the side element and any equipment carried thereon. 
     At the other end of the side element there is provided a receiving section  14  which comprises, e.g., a truncated cone-shaped funnel or female section  16 , which is diverging upwards when the side element is located in the position which is illustrated in FIG. 1. A section through this receiving section  14  is indicated by broken lines in FIG.  3 . From the narrow, lower end of the funnel  16  there extends downwardly a tubular section or pipe  18  or longitudinal fingers which are arranged along a circle, at the bottom of which are radially inwardly projecting flanges or claws  22 . These claws can be moved radially inwards towards the funnel&#39;s longitudinal axis by means of a spring device or outwards by means of suitable actuators (not shown) of any known type which can be operated by, e.g., a remotely operated subsea vessel or vehicle, hereinafter called a ROV (not shown), and which are mounted on the side element. Alternatively, they may also be moved radially inwards by means of such a vehicle. 
     In the pipe  18  there may be provided engagement elements in the form of ribs, lug or notches  26  which can be brought into engagement with below described complementarily provided notches, ribs or lugs of pin sections of adapters which are arranged to be connected with the side element, thus enabling the adapter to be secured in a fixed angular position about the funnel section&#39;s longitudinal axis, relative to the side element. 
     FIG. 2 illustrates a second embodiment of a side element  31  according to the invention. This has a hinge section  32  with two flange pairs  33 ,  34  comprising flanges  35 , 36  and  37 ,  38  respectively which are arranged spaced apart from each other. Between the flange pairs there may be placed an outwardly projecting section of the drilling template&#39;s central section, and through the flanges and this intermediate section there are provided mutually coaxial holes through which there extends a hinge pin  39 , thus enabling the side element  31  to be tilted in the above-mentioned manner. 
     In order to prevent the side element  31  from rotating further when it is pivoted from the upwardly pivoted to the downwardly pivoted position, between the flanges  35 , 36 , 37 , 38  of each flange pair  33 , 34  there is inserted a substantially disc-shaped accompanying element  41  and  42  respectively which similarly have a through-going hole through which the hinge pin  39  also extends, thus enabling the accompanying elements to rotate relative to the side element. Each accompanying element  41 ,  42  has a shoulder section  43  and a contact surface  44 . 
     It should be understood that the contact surfaces  44  or the accompanying elements  41 ,  42  in the illustrated position abut against contact surfaces (not shown) of the drilling template&#39;s central section. 
     The side element  31  can thereby be freely tilted up, i.e. pivoted anticlockwise about the hinge pin  39  from the position which is illustrated in FIG. 2 an angular distance of at least 90° without bringing along the accompanying elements  41 ,  42 . However, when the side element is pivoted the other way and down from its upwardly tilted position and when it reaches the downwardly tilted position, lateral surfaces of the flanges  33 , 34 , 35 , 36  come into abutment against the shoulders  43 , and because the accompanying elements&#39; contact surfaces  44  abut against the contact surfaces of the drilling template&#39;s central section, the side elements will be stopped in the downwardly tilted position. 
     The distance between the axis of the hinge pin  39  and the contact surfaces  44  of the side element  31  is greater than the distance between the hinge pin  6  and the contact surface  10  of the side element  1 . The forces which constitute a reactive moment which counteracts the above-mentioned static moment of the side element and the equipment carried thereon thereby become less in the case of the side element  31  than for the side element  1 . 
     The accompanying element could have been securely connected to the drilling template&#39;s central section, but the weight of the latter would then have been increased, which is disadvantageous, since the cranes which are employed for moving equipment from supply ships on board the platform have a limited lifting capacity. The drilling template&#39;s components can therefore be lifted on board the platform in smaller groups and mounted on the platform. In addition welding and screwing operations as well as possibly an X-ray control of welds are avoided, thus providing a reduction in the production costs for the drilling template. 
     The accompanying elements could further have been securely connected to the side element, but the elements would then have projected outwards from the drilling template&#39;s central section when the side element is located in its upwardly tilted position, which would have caused the drilling template to have a large transverse dimension, ruling out the possibility of lowering the drilling template through the moon pool. 
     FIG. 3 is a view of an adapter  51  for retracting pipes into the drilling template. The adapter comprises a downwardly facing pin section  52 . At the top the pin  52  has a cylindrical section or cylinder  53  whose diameter is slightly smaller than the inner diameter of the pipe  18  of the side element&#39;s receiving section  14 . At the bottom the pin has a male cone section  54 , whose largest diameter is slightly smaller than the smallest diameter of the side element&#39;s pipe  18 . The male cone section  54  can come into engagement with the claws  22  of a side element  1 ,  31 , in order thereby to secure the pin section  52  in engagement with the receiving section  14 . 
     In order to connect the adapter and a side element  1 ,  31 , the adapter&#39;s pin section  52  is first lowered and passed downwards into the receiving section  14 , whereby the respective conical sections cause a relative alignment and these sections extend coaxially. The pin section  52  is then lowered further, with the result that its barbed section  55  comes into engagement with the claws  22  and the pin section  52  is secured in the receiving section  14 . 
     This engagement can be released by the operation of the claw actuators for coupling the adapter  51  from the side element, e.g. if it is required to insert another adapter in this side element, the actuators, e.g. moving the claws radially outwards. 
     The adapter  51  may have a landing place or device  56  for, e.g., a tool for retracting a pipe. 
     FIG. 4 illustrates this adapter on a reduced scale, some components thereof having been removed. 
     FIG. 5 is a view of an adapter  61  with a pin section  62  which can be brought into engagement with the receiving section  14  of a side element, and an upper, upwardly extended truncated cone-shaped female section or funnel  63  for receiving, e.g., a pin section of a second adapter (not shown). Use of such an adapter  61  may be relevant, e.g., if the side element&#39;s receiving section  14  is not adapted to the pin section of the second adapter. 
     FIGS. 6 and 7 are views of other retraction adapters. 
     FIG. 8 is a view of an adapter with a U-shaped pipe, e.g. for receiving a plug from a pipe and inserting the plug in a second pipe. 
     FIG. 9 is a view of an adapter for inserting a plug. 
     In the adapters according to FIGS. 8 and 9 the male cone sections are short in comparison with the cylinder sections. 
     Even though the device according to the invention is specially suited for use with drilling templates where no guidelines extend therefrom to a platform at the surface of the sea, it will be understood that it may be employed with drilling templates which are connected to the platform via guidelines. Moreover, it will be understood that the side elements may be securely connected to the drilling template in the folded position wherein they extend horizontally.