Advances in understanding perforator penetration and flow performance

Conference · Sat Dec 31 04:00:00 EST 1994

OSTI ID:372457

Halleck, P M ^[1]

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1. Pennsylvania State Univ., University Park, PA (United States)

Planning of optimum completion procedures and interpretation of well test results require accurate estimates of perforation penetration and flow performance. New test procedures and results promise improved estimates of in situ penetration depths. The nature of perforation damage and underbalance surge mechanism are being studied using new flow tests supplemented by X-ray CT and pressure transient analysis. Some recent observations are: (1) permeability and mechanical damage may extend several inches from the perforation and is not limited to the visible crushed zone; (2) permeability damage is less severe near the tip of the perforation; (3) for low viscosity fluid and high permeability rock, the majority of surge cleanup occurs in less than 1 second. Surge flow volume is not an important factor, as long as sufficient underbalance is used. New models of perforation cleanup assume cleanup of debris and/or formation permeability damage depends on Darcy flow velocity exceeding a critical value. The critical velocity depends on rock and fluid properties and may be related to Reynold`s number. Such models illustrate the dynamics of cleanup and confirm that most of the cleanup occurs at early times and after small surge volumes.

• OSTI ID: 372457
• Report Number(s): CONF-940879--
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
03 NATURAL GAS
CALCULATION METHODS
FLOW MODELS
FORMATION DAMAGE
NATURAL GAS WELLS
OIL WELLS
PERFORATION
WELL COMPLETION