在许多情况下，如果在事件发生之前采取主动的方法，对油井的干预将会变得简单得多。

管状故障

当油井处于不受控的流动状态时，油管故障是最复杂且最具挑战性的问题之一。这种不受控状态通常是由于井筒屏障（套管或油管）失效，失效后暴露的地层无法控制储层压力而发生的。如果发生这种情况，则称为地下井喷 (UGBO)，或通常称为窜流。静水压力是有效压井的关键，这一点众所周知。根据故障发生的位置，在 UGBO 情况下，压井会变得越来越困难。

一般来说，浅层油套管故障有可能导致油管拉裂。拉裂是指油从井中流出，流到井筒套管外的地面。根据油流的严重程度，所有通往井口的通道都可能被破坏，因此减压井 (RW) 是唯一可行的修井方案。如果仍然有通道，浅层油套管故障可能提供形成液柱的机会，但通常需要某种形式的带油井修井措施才能进入出口点以下的油井（例如通过连续油管 [CT] 或压井作业）。

较深的油套管故障通常会限制可形成的液柱，从而限制井筒系统内产生压井所需的静水压力。很多时候，这些情况只能通过机械屏障结合液柱来解决。井眼结构和流道最终将决定合适的解决方案。

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In many cases, an intervention on the well would have been substantially less complex if a proactive approach had been taken before the event occurred.

Tubular failures

Tubular failures are among the most complex and challenging issues to address when a well is flowing in an uncontrolled state. This uncontrolled state typically occurs because the wellbore barrier (casing or tubing) has failed, and the reservoir pressure cannot be contained by an exposed formation post-failure. If this has occurred, this is referred to as an underground blowout (UGBO) or oftentimes termed as cross-flow. Hydrostatic pressure is the key to an effective kill as most are readily aware of. Depending on the location of the failure, establishing a kill can become increasingly more difficult in these UGBO cases.

In general terms, tubing and casing failures that are shallow have the potential to lead to broaching. Broaching is the term used when flow from the well exits to the surface outside of the wellbore casings. Depending on the severity of the flow, all access can be lost to the wellhead making a relief well (RW) the only viable option for intervention. If access is still feasible, shallow failures may offer the chance to establish a fluid column but typically require some manner of live well intervention to access the well below the exit point (via coiled tubing [CT] or snubbing).

Tubing and casing failures that are deeper generally limit the fluid column that can be established and thus limit the hydrostatic pressure available to generate a kill within the wellbore system. Many times, these situations have only been solved by mechanical barriers in combination with a fluid column. The configuration of the well and the flowpath will ultimately dictate the proper solution.

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