COFLEXIP & Services Inc. In    the    case    of    replacing    a damaged    riser    with    a    Coflexip riser,  a  new  flange,  if  not  already existing.          is     installed     on     the pipeline to terminate it.  The flange can     be     installed     on-bottom,     if there's     no     need     to     raise     the pipeline.      Any   type   of   approved underwater connector or underwater welding can be used to install the flange. The topside end of the flexible riser is transferred from the workboat to the platform using the platform   crane   or   an   air   tugger. Subsequently,  the  flexible  riser  is paid  off  the  back  of  the  boat  into the water. On   the   seabed,   the   flanged end  of  the  Coflexip  riser  is  mated to the pipeline.  The connection is easy  because  the  riser  is  flexible. In  addition,  maneuvering  the  riser into the clamps is simplified by the pipe's flexibility. These two Coflexip  advantages  decrease  the potential diver time, thus expense. J-tube risers, flexible versus rigid Replacing a J-tube riser with a new one of rigid pipe presents a costly and large-scale operation because of the A    Coflexip    riser    can    be    pulled through   a   J-rube   or   1-tube   with only  the  platform  crane  or  an  air tugger.      It   is   nor   necessary   to mobilize an expensive barge. normal   need   for   a   barge.      With Coflexip   you   can   avoid   both   the water-depth    difficulties    and    the barge. If the jacket has an available i- tube, the new Coflexip riser can be pulled  through  it  using  a  workboat and  a  platform-mounted  crane  or small tugger. If there is no available J-tube, you   can   install   a   clamp-on   riser even in depths where J-tube risers are  usually  required.    It's  easy  to install a Coflexip clamp-on riser in great water depths because there's no need for the precise alignments that   have   to   be   made   with   rigid clamp-ons. The    Coflexip    clamp-on    riser retains  another  advantage  of  the original   J-tube   riser.      It   can   be clamped to the inside of the jacket where   the   jacket   protects   it,   and there's no need for a riser guard. A reliable riser for less The technical and financial advantages   of   using   Coflexip   for risers and flowlines can be summarized as: • no   need   for   a   large   support vessel • no  need  for  heavy  underwater handling devices • no stalking-on •    no precise underwater measurements or alignments to be made • no clamping problems •    no    need    for    a    long    weather window • no special provisions for thermal expansion and contraction,    other    than    some slack at either end. Major oil companies are now using Coflexip flexible risers all over the world  in  working  pressures  up  to 10,000 psi. Mudslide protection For    protecting    a    pipeline    from underwater soil movement, Coflexip    offers    a    much    greater degree   of   safety   than   rigid   pipe solutions. Sediment creep and mudslides are a constant threat to offshore flowlines at the mouths of rivers, In a mudslide, the built in flexibility and    the    slack    of    the    Coflexip preventer riser damage due to the relative pipeline movement. and where there are severe bottom  currents,  earth  tremors,  or bottom    faults.        The    Mississippi Delta  and  Southern  California  are prime examples. Rigid    pipe,    even    with    ball joints. cannot  long  withstand  severe  soil movements.  Coflexip can. In  areas  of  unstable  soil,  you can ward off a break by incorporating    into    a    pipeline    a section  of  Coflexip  laid  out  in  an "S"    or    "U"    configuration.        The Coflexip   can   be   bent   to   a   very small   radius   of   curvature;   a   10- inch I.D.  line will bend to an eight- foot radius before damage. "Slack"  in  this  section  allows  the soil    movement    to    displace    the pipeline instead of damaging it. When the slack is taken up by a movement of the soil, a new "S" or "U " section can be inserted.  Of course  a  Coflexip  riser  or  flowline can  be  laid  out  with  enough  slack to act as its own mudslide protector.