A measuring head is the primary piece of equipment the wireline comes into contact with off the drum. The measuring head is composed of a number of wheels which assist the wireline on its way to the winch they usually additionally measure essential wireline information.
While a liner string is very similar to casing string in that it is made up of separate joints of tubing, the liner string is not run the complete size of the well. A liner string is hung within the well by a liner hanger, after which cemented into place. In some wells, protection or intermediate casing is run to separate difficult areas or problem zones, including areas of excessive strain or lost circulation. The widest type of casing is called conductor pipe, and it normally is about 30 to forty two inches in diameter for offshore wells and 16 inches in diameter for onshore wells.
A line wiper operates in a lot the same method as a pack-off sub, besides that the rubber factor is much softer. Hydraulic pumps exert force on the rubber factor until a light-weight stress is exerted on the wireline, cleansing grease and well fluid off the line within the course of. Pack-off subs make the most of hydraulic strain on a two brass fittings which compress a rubber sealing component to create a seal across the wireline.
Pack-offs can be hand pumped or compressed through a motorized pumping unit. The grease injector head is the primary apparatus for controlling properly strain while operating into the outlet.
The grease head makes use of a collection of very small pipes, known as circulate tubes, to decrease the pressure head of the well. Grease is injected at excessive pressure into the bottom portion of the grease head to counteract the remaining well strain. Pump-in subs (also referred to as a circulate T) permit for the injection of fluid into the stress control string.
The next dimension in casing string is the floor casing, which can run a number of thousand feet in size. Here, a well is drilled to a sure depth, cased and cemented, after which the properly is drilled to a deeper depth, cased and cemented again, and so on. A rounded part of pipe with an open hole on the top, a information shoe is related to the first casing string to guide the casing crew in operating the casing into the nicely. Additionally, the surface of the casing has spring-like centralizers attached to them to help place in casing string within the middle of the nicely.
Normally these are used for wellsite strain testing, which is typically carried out between every run into the well. They can also be used to bleed off pressure from the string after a run in the nicely, or to pump in kill fluids to manage a wild nicely.
Channeling is the place massive, contiguous voids in the cement sheath form, sometimes attributable to poor centralization of the casing. Both of these conditions can, if necessary, be fastened by remedial electrical line work. Our wireline products are designed to securely function in excessive RF areas. Our solutions supply high reliability and enhanced job site security to help your group achieve mission success. In an effort to economize, sometimes a liner string is run into the properly instead of a casing string.
If the software is to turn into caught within the well, the weak point is where the device would first separate from the wireline. If the wireline were severed anyplace else along the road, the software turns into much more troublesome to fish. Two of the biggest issues found in cement by CBT's are channeling and micro-annulus. A micro annulus is the formation of microscopic cracks within the cement sheath.