A Study Of Abnormal Annulus Pressure And Methods Of Safe Production For Tairm High Pressure Gas Wells

Duirng the peirod of production，abnormal annulus pressure (or sustained casing pressure)will directly affect the safety of gas wells and ifeld operations personnel in high一ultra highpressure gas wells. Study the causes of abnormal annulus pressure, mechanism of changes andthe corresponding test analysis method of high-ultra high pressure gas wells productionsafety has important practical significance.Through extensive literature research, conclude that the thermal casing pressure,sustained casing pressure (SCP)，operator-imposed casing pressure are three types ofannulus pressure; invasive way of the gas in slurry，cementing quality，tubular goods’ integrityfailure, damage to the cement sheath due to temperature and pressure impact annulus pressure;slurry of matirx permeability and interface channeling are two mechanisms leading toincreased conductivity of the annulus. Understanding of the status quo on the the Tairm highpressure gas well, summairze the potential leak path of the annulus and abnormaldiscirmination method. By example and evaluation of test methods analyzes the current Kela2gas ifeld, Dina2gas field put bleed-ofFbuildup test existing two cases; in which the pressurebuildup patterns can be divided into three situations: the pressure stabilizing at a new，low-pressure level; restoring to oirginal pressure within24hours; maintaining a irsing trend.With the typical well annulus pressure by changing the production system determines thereason for the exception. Establishing the thermal annulus pressure mathematical modelcombining with B2well calculates temperature (86°C) and pressure (107,48MPa) leading tothe production casing integrity failure.On the basis of above theoretical analysis and realities, combining the gas well dynamicmonitoirng, annular pressure management and well control safety management establishesappropirate security in the Tairm Kela2gas ifeld, and Dina2gas ifeld production methods.