Perforating for Fracturing—Best Practices and Case Histories

Abstract

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractIn 2004, SPE 90238, "Perforating and Hydraulic Proppant Fracturing in Western Siberia, Russia," provided recommendations for perforating in Western Siberia, 1 an area where hydraulic fracturing is booming and considered second only to the North America region, with over 5,000 fracturing treatments performed each year. One of the issues that has become obvious over the past two years is the limited understanding of the importance of using well and reservoir data as major factors in the selection of perforating programs to prevent premature screenouts.In recent years, several operators have concluded that maximizing production from most wells in western Siberia fields requires the placement of large quantities of coarsesized proppant using the least damaging fluid systems possible in the fracturing applications. For production optimization, the proven trend is "larger (proppant sizes) and bigger (jobs)" using the lowest acceptable polymer loading in the frac fluids to minimize gel damage.To achieve successful placement of the designed optimized fracturing treatment, all factors that could lead to a premature screenout should be eliminated. Improper perforating practices have proven to be one of the primary limitations and are often proven as the number one reason for past screenouts. Using the preferred perforating guns and charges for a specific application reduced the total screen-out percentage to less than 5%. The key to proper selection of perforating methods included using API RP 19B data and simulation software that calculates downhole conditions. This paper describes several case histories in moderately hard and moderately soft rock reservoirs, using both big hole and deep penetrating guns, showing results that proved using proper perforating practices could eliminate screenouts. Furthermore, the authors describe how a different approach (hydrajet perforating) was used to provide entry from the wellbore to the formation. Hydrajetting will be compared with conventional (shape-charge) perforating techniques prior to hydraulic fracturing. Case histories for multi-zone pin-point stimulation will be provided.

Pinpoint Fracturing Technologies: A Review of Successful Evolution of Multistage Fracturing in the Last Decade

“…This process effectively stimulates horizontal openhole wells where using conventional methods to create distinct individual fractures has not been possible. • Initially developed in 2003, the hydrajet perforating annular path pumping (HPAP) with packer diversion method was proven as a viable way of stimulating multiple pay intervals in cased, cemented, imperforated, vertical well completions using CT (McDaniel et al 2007). It uses readily available 1.75-in.…”

“…The HPAP with PPD method also has been used successfully in Russia (Pongratz et al 2007). Conventional completions involving stage fracturing can take weeks to perform.…”