Abstract: An automated system for assessing pumpoff risk can be used to warn operators and/or control machinery in order to avoid pumpoff. Pumpoff risk is assessed through the use and/or comparison of one or more models of pumpoff risk. These models can include a sand build up model (e.g., to determine the threshold buildup size where pumpoff risk is too great), a line speed increase model (e.g., to determine the maximum flow rate allowable given a maximum support line feed rate), a residual error comparison model (e.g., to compare the deviation of predicted tension from actual tension), and a statistical analysis model (e.g., to determine likelihood of pumpoff given statistical probability of each of a multitude of possible scenarios).

Abstract: A pump-down method includes deploying a tool in a well via a wireline and measuring a tension of the wireline. The method also includes determining a difference between the measured tension and a reference tension. The method also includes updating at least one of a pump rate and a wireline speed used for pump-down of the tool based on the difference and at least one control parameter obtained at least in part from prediction model results.

Abstract: Certain aspects and features of the present disclosure relate to an automated system for assessing pumpoff risk, which can be used to warn operators and/or control machinery in order to avoid pumpoff. Pumpoff risk is assessed through the use and/or comparison of one or more models of pumpoff risk. These models can include a sand build up model (e.g., to determine the threshold buildup size where pumpoff risk is too great), a line speed increase model (e.g., to determine the maximum flow rate allowable given a maximum support line feed rate), a residual error comparison model (e.g., to compare the deviation of predicted tension from actual tension), and a statistical analysis model (e.g., to determine likelihood of pumpoff given statistical probability of each of a multitude of possible scenarios).