Improved Cement Placement on North Sea Wells Using a Cement Placement Simulator

Abstract

A new computer based cementing simulator is described that quantifies the effect of key displacement variables such a s geometry, standoff, fluid rheology and density, and flow rate. The paper shows how to optimise cement placement within the fracture and pore pressure constraints of the well and demonstrates its use through case studies from the North Sea. The technique assesses the quality of mud removal and cement placement as well a s estimating the circulating pressures throughout the job. The examples illustrate how existing rules of thumb can be confusing and how reliable cement jobs can be achieved through quantitative design procedures.

Visco-plastic fluid displacements in near-vertical narrow eccentric annuli: prediction of travelling-wave solutions and interfacial instability

“…Ravi, Beirute & Covington 1992). These criteria have been examined further in Ryan, Kellingray & Lockyear (1992), where a cementing placement simulator that assesses the quality of mud displacement is also described. In particular, the yield stress criterion has been refined to distinguish between two cases.…”

Simple Approach to the Cleanup of Horizontal Wells With Prepacked Screen Completions

“…In addition, the time taken to deal with losses and with flowback-lost liquid would add significantly to well cost. 4. We expected the reservoir to be extremely homogeneous, which reduced concern over selective cleanup of high-permeability bands.…”

“…For certain oil-based muds (OBM's), displacement to completion brines can result in the fonnation of thick damaging sludges owing to poor displacement and fluid incompatibilities. 4. Despite use of corrosion inhibitors, acid breakers can cause corrosion problems for metals commonly used in screen design, such as 316L stainless steel.…”