Hydraulic Fracturing Techbook 2018

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44 | August 2018 | SPONSORED CONTENT hours, respectable fluid-end operating life assuming no irreparable failures. This translates to two fluid ends per pump each year. An hour of a maintenance technician's time is estimated (fully burdened) at $100 per hour, not including truck and tools sunk costs or travel time. The fluid end model for this analysis is a 10-inch between center-bore quintuplex running #4 valves and valve seats. The Legacy flanged-style fluid end costs $62,000 and the Frac 1 CONNECT™ costs $49,995 (table 1). Opportunity cost for a Legacy-style fluid end idled for repairs will be the expense of purchasing a new fluid end as a temporary replacement. Traditional Valves and Valve Seats Valves are the first internal consumables routinely replaced. Industry standard valves on average cost $50 each. Ten valves per quintuplex fluid end are typically swapped out after 25-35 hours of harsh environment pumping and depending on proppant pumped. It is commonly accepted the second valves on a set of valve seats lasts 75-80% as long (because preceding valves slightly deformed each seats' strike-face). Kerr Pumps is field testing a valve design engineered to extend the maintenance interval at a commensu- rate price point that does not affect the valve seat strike-face. On average, traditional valve seats cost $60 each and are swapped on 30-60 hour increments. Super Seats™ Fluid-end technicians dread valve seat replacement. Kerr Pumps' patent-pending Super Seat™ reliably extends maintenance intervals over five times (v. traditional valve seats) in the worst pumping envi- ronments – and measurably longer in more favor- able conditions. The patent-pending "shoulderless" seat with tung- sten carbide ring at the strike-face has consistently performed up to 5X (and sometimes 10X) longer for less than 2X cost ($89 for a #4 valve seat). Kerr Pumps' Super Seats™ consistently ran up to 200 pumping hours in the Haynesville Shale before routine replace- ment as a precaution. Extending Mean Time Before Failure (MTBF) Fluid-end failures are an unfortunate reality with intense duty cycles in harsh environments. Yet seeking incremental increases in operating life within the eco- nomic limits of today's frac patch can be a challenge. Anyone reading this who has ever tackled economic time and cost analysis understands the many unex- pected frac job variables that can make a well-thought, controlled analytical study look absolutely out of con- trol. Anything that can happen, might happen. Should one factor for each "what if " potential failure mode to build a "contingency bank" of time and money? In 2014 Kerr Pumps entered the market with replacement fluid ends for standard frac pumps and began experiencing varied failures at frequencies sim- ilar to other suppliers. Intersecting bore cracks are the kiss of death; that fluid end is destined for the bone- yard. Shifting to stainless steel pushed intersecting bore cracking out to a high-hour, end-of-life failure mode – if it happens at all anymore. Packing-bore Washout Packing-bore washout is today's most prominent failure mode (roughly 40% of all fluid ends). It isn't a widow-maker, but it can sideline Legacy-style fluid ends for a $5,000 per-bore weld repair (including transportation) for up to two months. A $62,000 backup fluid end must be purchased as a replace- ment (table 2). Maintenance usually requires a couple of hours for each fluid end swing with two service technicians. Plus, it is widely acknowledged that most weld repairs may only return a fluid end to operating service for another ~ 150 pumping hours before end-of-life cracking failure. Total cost Super Seat™ Fluid End plus Valve 6 Month Total Seat Maintenance Costs Legacy F1C Savings Fluid End Cost $62,000 $49,995 19% Valve Seats $20,800 $6,540 69% 6 Month Total $82,800 $56,535 32% 12 Months $165,600 $113,070 $52,530 20 Pump Fleet $3,312,000 $2,261,400 $1,050,600 TABLE 1: PURCHASE PRICE AND VALVE SEAT MAINTENANCE COST COMPARISON

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