WIRELINE
General Purpose
Measuring line or wireline as commonly called is probably the most important service tool .This wireline makes possible manipulating of sub-surface controls and other service tools many thousand feet from the surface.
History
The earliest wireline used suffered from many problems like stretching and was required to be calibrated to get accurate depth. So it became necessary to develop high strength materials to get sufficient tensile strength in a small diameter wire as possible to:
• Reduce the load of its own weight to a minimum.
• It can run over smaller diameter sheaves, wound on a smaller diameter spool.
The most improved material for wireline is improved plow-steel .In wells where hydrogen sulfide is encountered ,cold-drawn plow-steal wireline may be affected by hydrogen embrittlement resulting in reducing service life so we use 316 stainless steel although its tensile strength is lower than the plow-steal but it has good resistance to the hydrogen embrittlement.
Operating Procedures
During the wireline operation :
• The maximum permissible pull on the line must never exceed the elastic limit
• Normally 50% of the maximum breaking strength is used as working limit
• After ever four hours of jarring , pull out and cut off 20’ of the wireline
• Braided cables are used when high breaking strength is required
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WIRELINE CREW
A wireline crew consists of two men : the operator and his helper. It is important that each one knows what his job is and his co-works also. in order that no misunderstanding may occur on a customer's location, we will attempt to clarify each one’s job.
Operator
Upon arriving at location , after changing to the proper clothing and safety gear, the operator should first check the location and the position of the unit in accordance with safety regulations. Check and make sure the unit is fastened to the platform or that the truck is properly blocked.
The operator’s job is to run the unit manipulating the line to perform whatever is necessary to accomplish the job. He is to instruct and assist helper in lifting the tools.
Helper
He should remove the equipment necessary to the rig up on the well and place it near the well. Below is a list of the following pieces:
• Gin pole
• Rope blocks
• The lubricator
• Hay pulley
• Hammer
• Tree connection with proper seal rings.
The helper between the trips is to busy himself preparing the tools needed on the next trip and keep the unit clean all times. He is also expected to study the running and pulling tools being used.
Note: the helper should abide the operator choice unless it endangers his or her life.The operator and the helper should work as a team to achieve a job successfully .
Safety Rules
• Never hammer or climb on the lubricator while it is subjected to pressure.
• Never open the master valve or swab valve without being assure that the pressure above and below the valve Is equalized.
• When releasing pressure from the lubricator through the needle valve turn your head away from valve and open your mouth to prevent damage to your ear drums.
• No smoking is allowed within 100 feet of the well head.
• Never wash the tools and equipment with flammable solvent or hydrocarbon mixtures.
• Think the project through before proceeding with any operation around the well site.
• All wireline safety equipment should be inspected on a routine basis and carried in its proper place on the wireline truck.
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WIRELINE SERVICES
What are wireline services?
Running one or several tools on either a single strand wire or braided cable inside the well.
What are the advantages of wireline?
• Simple,
• Quick and
• Economical compared to other means.
What are the disadvantages of wireline?
• The operator is physically very remote.
• The uncertainty of cable stretch (i.e., depth).
• Limitation in means of monitoring and operating the tools.
• Require highly skilled personnel.
Capabilities offered by wireline are numerous, such as :
• Isolation of the formation.
• Operating of sliding side door.
• Installation/retrieval of downhole of SSSV, chokes, regulators.
• Running/retrieval of downhole P & T gauges.
• Removal of wax by scraping.
• Installation/retrieval of valve in side pocket mandrel.
• Removal of sand and produced solids.
• Installation of through tubing bridge plug.
• Using electric conductor cable, packers can be run.
• Checking the available depth and diameter.
• Fishing.
What are required (in addition to tools string and cable)?
• Ability to lower and retrieve the tool string.
• Monitoring tool position and cable tension.
• Handling and alignment pulleys.
• The ability to work with live wells.
• A blow out preventor (BOP).
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WIRELINE SURFACE EQUIPMENT
Generally, surface equipment is anything that has to be attached to the wellhead in order to perform the job.
In order to accomplish wireline work we must have some means of getting the wireline and wireline tool string into the bore of the tubing under pressure. Since all wells that we service will contain or are subject to contain pressure, we must use a safe and sensible means of gaining access to the well bore with our wireline tools.
The figure shows the basic surface equipment which is normally used to perform wireline work in the well.
Load Binder and Chain | • Used to attach the telescoping gin pole to the tree. |
Telescoping Gin Pole | • It can be in two sections or three sections. • The pole is first of all attached to the tree. • Rope blocks are attached to the top section then extended. |
Gin Pole Bins | • Used to keep the section extended. • Some wireline companies employ a saddle attached to the wireline valve with a clamp. • The advantage of this is it speeds up the rigging up operation as a chain and binder is not needed. • A disadvantage is that you are limited to the amount of lubricator you can put up. |
Rope Blocks | • Rope blocks and ropes are used to raise the lubricator. • Care must be taken to keep the rope free of dirt and greese. • Precautions must be taken not to cut the rope and worn out rope should be changed. |
Tree Connections | • the tree connection used depend on what the customer has to rig up on top of his crown valve. • After removing the top, on the inside of most trees, you will find a thread that is used to hang the tubing with. • This can be used if the tubing pressure is not too high. • The tree connection then is adapted to the blowout preventers. |
Blow Out Preventers | • Often refered to as a wireline valve. • A means of isolating the well pressure from the lubricator sections without cutting the wireline. • This is done by closing a set of rubber rams on the wire and bleeding the well pressure from the lubricator. • This is often necessary in fishing operations. |
Lubricator | • It is used to run swabing or perforating tool and It provides method for sealing off pressure (making the lowered tool is the first subjected to the well pressure) |
Quick Unions | • Screwed or welded on the ends of lubricator sections to extend it • The unions slip into each other and a large nut is screwed to the female half to hold them together. • They are considered safe because it would be impossible to unscrew them while there is a presence of pressure. |
Stuffing Box | • Is used as means of running the wireline into the lubricator that is subjected to well pressure. • All sizes of slick wireline can be used with a standard stuffing box. |
Hay Pulley | • It can be defined as a pulley used to change the direction of line pull. • While rigging up the surface equipment, the wireline from the unit is directed parallel to the ground level to the X–mas tree and then changes direction through the hay pulley up to the top of the lubricator. |
Wireline Clamp | • Its function is to clamp the wireline without damaging the wire. • Used to keep the tools from falling out of the lubricator while raising it up. • Used in fishing operations to pull on the wireline. |
to be Continued
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