المشاركات

عرض المشاركات من مايو, 2020

The Effect of Weighting Materials on Cement

صورة
Attapulgite Attapulgite  belongs  to  a  quite  different  family  of  the  clay  minerals  Attapulgite-based  muds have excellent viscosity and yield strength and retain these properties when mixed with salt water. However, they have the disadvantage of suffering high water loss thereby giving poor sealing properties across porous and permeable formations. Organophillic Clays  Organophillic clays are made from normal clays (bentonite or attapulgite) and organic cations. The organic cations replace the sodium or calcium cations originally present on the clay plates. Organophillic clays can be dispersed in oil to form a viscous structure similar to that built by bentonite in water. POLYMERS : Polymers   are   used   for   filtration   control,   viscosity   modification,   flocculation   and   shale stabilisation. When added to mud, polymers cause little change in the solid content of the mud. Polymers  are  chemicals  consisting  of 

The Effect of Weighting Materials on mud

صورة
 Barite Barite  (or  barytes)  is  barium  sulphate,  BaSO4  and  it  is  the  most  commonly  used  weighting material in the drilling industry. Barium sulphate has a specific gravity in the range of 4.20 - 4.60. The specific gravity of Most commercial barite contain impurities including quartz, chert, calcite, anhydrite, and various silicates which slower its specific gravity. It is normally supplied to a specification where the specific gravity is about 4.2.  Barite is preferred to other weighting materials because of its low cost and high purity. Barite is normally used when mud weights in excess of 10 ppg are required. Barite can be  used to achieve densities up to 22.0 ppg in both water- based and oil -based muds. However, at very high muds weights (22.0 ppg), the rheological  properties  of  the  fluid  become  extremely  difficult  to  control  due  to  the  increased solids content. 2. Iron Minerals Iron ores have specific gravities in excess of 5

WELL CONTROL SYSTEM

صورة
Blowout preventers (BOPs) Blowout preventers (BOPs), in conjunction with other equipment and techniques, are used to close the well in and allow the crew to control a kick before it becomes a blowout. Blowout preventer equipment should be designed to: 1. Close the top of the hole. 2. Control the release of fluids. 3. Permit pumping into the hole. 4. Allow movement of the inner string of pipe. You may also like this topic Handling Tools for Drilling BOPs  equipment  are  selected  based  on  the  maximum  expected  wellbore  pressures.  The pressure  rating,  size  and  number  of  BOP  components  must  be  determined  by  the  Drilling Engineer prior to drilling the well. Basic  types  of  blowout  preventers  on  drilling  rig  are:  annular  preventers,  ram  preventers, rotational preventers and diverters. BOP s are rated by API as 3M (3000 psi), 5M, 10 M and 15 M. For HPHT, BOPS are either 15 M or 20 M. The recommended component codes for desig

Handling Tools for Drilling

صورة
Spinning Chain A relatively short length of chain attached to the tong pull chain on the manual tongs used to make up drill pipe. The spinning chain is attached to the pull chain so that a crew member can wrap  the  spinning  chain  several  times  around  the  tool  joint  box  of  a  joint  of  drill  pipe suspended in the rotary table. After crew members stab the pin of another tool joint into the box  end,  one  of  them  then  grasps  the  end  of  the  spinning  chain  and  with  a  rapid  upward motion of the wrist "throws the spinning chain"—that is, causes it to unwrap from the box and coil  upward  onto  the  body  of  the  joint  stabbed  into  the  box.  The  driller   then  actuates  the makeup cathead to pull the chain off of the pipe body, which causes the pipe to spin and thus the pin threads to spin into the box. You may also like this topic Drilling Mud Circulation System Tongs The  large  wrenches  used  for  turning  when  ma

Bottom hole assembly

صورة
 Float Collars A float collar is a one way valve placed at one or two joints above the shoe. The float collar provides the same functions as a float shoe by preventing fluid back flow into the casing: mud backflow during running in hole and cement slurry backflow after cement displacement. The distance between the shoe and float collar is called Shoe Track. The float valve can either be a ball type or a flapper, Figure below. Flapper type valves are normally used where a small hydrostatic pressure difference is expected, providing a better seal than a ball type valve . Y ou may also like this topic Drilling Rig Rotary Table Sizes Centralisers A centralizer is a mechanical device attached to the outside of casing. The primary purpose of this equipment is to center the casing in the hole and provide a uniform flow passage with relatively equal frictional pressure losses surrounding the casing. Another major function of centralizers in a deviated hole is t

Introduction to Drilling Bits ROLLER CONE BITS

صورة
DRILLING BITS: ROLLER CONE BITS: As the name implies, roller cone bits are made up of (usually) three equal-sized cones and three identical  legs  which  are  attached  together  with  a  pin  connection.  Each  cone  is  mounted  on bearings which run on a pin that forms an integral part of the bit leg. The three legs are welded together and form the cylindrical section which is threaded to make a pin connection. The pin connection  provides  a  means  of  attachment  to  the  drill  string  Each  leg  is  provided  with  an opening  for  fluid  circulation.  The  size  of  this  opening  can  be  reduced  by  adding  nozzles  of different sizes. Nozzles are used to provide constriction in order to obtain high jetting velocities necessary for efficient bit and hole cleaning. Mud pumped through the drillstring passes through the bit pin bore and through the three nozzles, with each nozzle accommodating one third of the total flow, if all the nozzles were of the

ماهي سوائل الحفر التي يتم استخدامها في عمليات حفر الابار البترولية

صورة
سوائل الحفرهي المادة التي يتم بها رفع فتات الحفر من قاع البئر الي السطح ليتم حفر اجزاء اخري والوصول الي العمق المطلوب حفره وتعرف ب Drilling Mud ويمكن الحفر باستخدام الطفلة ذو الاساس المائيwater base mud او الطفلة ذو الاساس الزيتي oil base mudاو ممكن الحفر بالغازات وهي حاله نادره يمكن استخدامها في عمليات الحفر المختلفة. فوائد سائل الحفر: 1- يقوم سائل الحفر بعمليه التبريد والتزييت المناسب للدقاق اثناء عمليه الحفر وهذا ما يساعد علي العمر الافتراضي لدقاقات الحفر التي تكون في بعض الاحيان مرتفعة الثمن نظرا لصناعتها من اكثر العناصر صلابه وصلاده في الكون وهو عنصر الماس ذو القيمة العالية والثمن الباهظ ويرجع استخدام هذا العنصر في صناعه الدقاق لا نه يقوم بتفتيت وتكسير الخرسانة والصخور النارية بل يودي الي تفتيت الحديد والفولاذ الي قطع صغيره ليسهل عمليه رفعها باستخدام سائل الحفر. 2- يحتوي هذا السائل علي مجموعه من الضغوط التي تعمل علي ضغط عمود الحفر داخل البئر لكي لا يحدث عمليه انفجار للبئر والخروج عن السيطرة. 3- يقوم سائل الحفر ذو الخاصية الرغوية برفع الفتات من الصخور المحفورة وضغطها الي اعلي ليتم

Oil Well Drilling mud pits

صورة
MUD PITS Mud pits are required for holding an excess volume of drilling mud at the surface. This surface volume  allows  time  for  settling  of  the  finer  rock  cuttings  and  for  release  of  entrained  gas bubbles  not  mechanically separated.  Also,  in  case  some  drilling  fluid  is  lost  to  underground formations, this fluid loss is replaced by mud from the surface pits. The settling and suction pits sometimes are dug in the earth with a bulldozer but more commonly are made of steel. Mud pit compartments are also called shaker pits, settling pits, and suction pits, depending on their main purpose.. A large earthen reserve pit is provided for contaminated or discarded drilling fluid and for rock cuttings. This pit also used to contain any formation fluids produced during drilling and well testing operations. mud pit usually lined with a single-ply 20 or 30 milmeter polyethylene .liners that resist punctures and wind damage to prevent any contamination

Drilling Mud Circulation System

صورة
CIRCULATING SYSTEM A major function of fluid-circulating system is to remove the rock cuttings from the hole as the  drilling  progresses.  Drilling  fluid  is  most  commonly  a  suspension  of  clay  and  other materials in water called drilling mud (will be discussed in details). The drilling mud travels (1) from the steel tanks to the mud pump, (2) from the pump to the high -pressure surface connections to the drill string, (3)through the drill string to the bit, (4) through the nozzle s of the  bit  and  up  the  annular  space  between  the  drill string  and  hole  to  the  surface  and  (5) through   the   contaminant-removal    equipment    back   to   the   suction   tank.The   principal components of the rig circulating system include Mud pumps   Mud pits   Mud mixing equipment Contaminat- removal equipment  MUD PUMPS Mud pumps always have used reciprocating positive-displacement piston. Both two-cylinder (duplex)  and  three  cylinder  (t

Drilling Rig Rotary Table Sizes

صورة
Land drilling rigs can be classified according to the drilling depth into different sizes Light duty rigs: drill holes from about (3000-5000 ft) deep or (1000-1500 meters Medium duty rigs: drill to depth ranging from (4000-10000 ft) or (1200-3000 meters Heavy duty rigs: drill holes from about (12000-16000 ft) deep or (3500-5000 meters Ultraheavy duty rigs: drill holes from about (18000-25000 ft) deep or (5500-7500 meters ROTARY DRILLING RIG COMPONENTS The main function of a rotary rig is to drill a hole, or as it is known in the industry, to make hole Making hole with a rotary rig requires not only qualified personnel, but a lot of equipment as well In order to learn about the components that it takes to make hole, it is convenient to divide them into  a  number  of  main  systems:  power,  hoisting,  rotating,  circulating,  well  control,  and  well monitoring  system.  Various  components   comprise  the  systems,  but  all  require  power  to  make them

Machining, Rotary Drilling Methods

صورة
CABLE TOOL METHOD Cable tool method has its beginnings 4000 years ago in China. it was the earliest drilling method and  has  been  in  continuous  use  for  about  4000  years.  The  Chinese  used  tools  constructed of bamboo  and  well  depths  of  3000  ft  are  recorded.  However,  wells  of  these  depth  often  took .generations to complete Cable tool rigs are sometimes called pounders, percussion, spudder or walking beam rigs. They operate repeatedly lifting and dropping a heavy string of drilling tools into the boreholes. The drill bits  breaks  or  crushes  consolidate  rock  into  small  fragments.  When  drilling  in  unconsolidated .formations, the bit primarily loosens material Water, either from the formation or added by the driller, mixes the crushed or loosened into a slurry at the bottom of the borehole. An experienced cable tool driller feels when the accumulated slurry has reached the point where it is reducing bi penetration to a

Drilling problems Lost Circulation

صورة
LOST CIRCULATION Lost circulation is the loss of mud or cement to the formation during drilling operations. Lost :circulation causes . increased well costs, due to lost rig time and loss of expensive drilling fluid -  . loss of accurate hole monitoring -  . well control problems -  Mud losses can be experienced as a result of either natural losses, induced fractures during .drilling operations or due to excessive overbalance NATURAL LOSSES Natural losses occur in rocks containing porosity and permeability or with natural fractures Three types of formations can be recognised  Coarse Sands and Gravel Beds : Usually occur near the surface where the formation is both porous and highly permeable: permeability in excess of 10 to 25 Darcy  Natural Fissures or Fractures Natural fissures and fractures usually occur in limestones and chalks which have been subjected to tectonic activities or to leaching by acids. Losses in the formations is usually