The following planning guidelines shall be adhered to: The casing tally (bottoms up) shall be made listing the pipe as when racked. Casing length shall be casing running length and not total length. The casing tally shall be checked by multiplying the number of joints to be run in the hole by the average length … Casing and Liner Operations Planning
The centralisation of casing and liners as well as the correct positioning of the centralisers are essential parts of any casing or liner job. The main reason for centralisation is to ensure a homogeneous distribution of cement around the casing. No centralisation or poor centralisation will cause channelling of the cement and hence produce a … Casing Centralisation
1. General Running Procedure 1. Visually check each joint of casing/liner to ensure all joints are clear of foreign matter, measured and drifted. Note: To prevent foreign matter entering the string whilst running it is necessary to: use a casing/liner cover where appropriate ensure dope is only applied to the pin end joint prior to … Casing and Liner Running Procedures
Procedures for leak-off and limit tests. Leak-off and Limit tests are carried out during the drilling phase of the well. The BOP is closed around the drillpipe, and the well is slowly pressured up, using mud. At the first sign of fluid leak-off into the formation the pumping is stopped. Leak-off tests are carried out … Procedures for leak-off and limit tests (LOT, LT, FIT)
This article describes the methods to quantify the different casing loads are presented. Internal and external pressure profiles are generally independent and therefore separate design loads will be generated. The comparison of the internal and external pressure loads results in either a collapse load line or in a burst load line. Collapse load The collapse … Pressure (Collapse and Burst) loads on casing
Introduction to Casing Design Loads (Collapse, Burst and tension Load) 1 Collapse Load The design load case for collapse is based on a partial evacuation of the casing string. For partial evacuation during the drilling phase, the internal pressure profile is based on mud losses to pore pressure. Full evacuation after a blow-out is evaluated … Casing Design Loads
The consequences of permafrost thaw resulting from increased surface temperatures during drilling and production, affect casing design in a number of ways. Permafrost is a permanently frozen soil. Soil at temperatures below freezing point may or may not contain ice, depending upon pore fluid salinity, pore pressure, and soil type. Permafrost can be continuous from … Permafrost well
Casing wear is very important as it effects the system integrity. A casing scheme is designed based on the properties of the chosen casing. Casing wear changes the thickness of casing walls and therefore changes its properties related to its capability to withstand the various loads exerted on it. This should be taken into consideration … Casing wear and solutions
The load determination for a stove pipe, foundation pile or marine conductor is a complex issue. This determination is usually followed by specialised stress analysis resulting in the involvement of a Structural Engineering department. The load determination and related stress analysis for a conductor casing is less complex, but still requires a good knowledge of … Stove pipe, foundation pile, marine conductor and conductor string
1 Evacuation during drilling Collapse loads occurring during drilling are usually the result of borehole evacuation due to natural or induced losses. There are however other cases to be considered. 1.1. Internal pressure profile In a losses situation, the mud column will drop until the pore pressure at section TD is just balanced by the … Collapse loads