Collapsible Landing Sub Deployed with Mechanical Inflow Test Packer Allows Liner Lap Testing and Shoe Track Drill Out in One Trip, Decreasing Costs and Increasing Reliability

Abstract

Liner lap testing operations in the gas fields have evolved to include shoe track drill out operations in the same trip. Typically, a drilling BHA is run and spaced below an inflow test packer to drill out the shoe track to 20ft above the shoe. A landing sub or no-go lands in the liner top at the predetermined bit depth to activate a test packer mechanically. This order of operation exposes the packer elements to debris circulated from drill out operations resulting in damage to the packer elements or incorrect engagement of the packer elements and casing ID. Deploying a hydraulically activated collapsible land sub in conjunction with the mechanical inflow test packer allows a change in the order of this operation. The collapsible landing sub is run in hole below the test packer and lands in the liner top to facilitate the packer activation. The liner lap test can be conducted with little or no drill-out debris in the well. Once the liner lap test is considered successful, the landing sub is hydraulically collapsed allowing entry into and below the liner top. Drilling operations can then resume without concern to packer element damage. Applications of this system include liner lap testing and any subsequent drilling operation in the same trip. This paper introduces and discusses the step change in operational liner lap testing procedures while incorporate this new approach to market technology of the collapsible landing sub. It describes the lesson learned and the limitations of the previous method of conducting this operation. It analyzes and compares actual job data and success rates between the previous methods and methods incorporating the new technology. This paper shows that using the collapsible landing sub in conjunction with the mechanical in flow test packer cost reduction and increases reliability and profitability in these operations.