Hydraulic Fracturing Techbook 2018

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46 | August 2018 | SPONSORED CONTENT Bolt-in Sleeve Retainer Packing Retainer Nut Removable Stuffi ng Box Sleeve Packing In 2017 Kerr Pumps created its patent-pending Frac One™ bolt-on cover cap design to combat this problem. By spreading load to 8 studs per front bore, load for each stud was reduced to only 35,934 pounds. Now each nut needs only 700 lb-ft of torque to dis- sipate cyclic stress. Packing Retainer Nut Damage Whether related to maintenance or intense pulsa- tion, a threaded packing retainer nut on the plunger side of a fl uid end will gradually back-out from pul- sation. Once a packing retainer nut enters the stroke of a plunger clamp, the clamp begins smashing into the backed-out nut. In a Legacy fluid-end this hammering effect likely will damage threads cut into the fluid end to hold it –even to irreparable failure. To remove all threaded bore connections, Kerr Pumps utilized a bolt-in sleeve retainer that is ID threaded for the packing retainer nut. If a packing nut backs out and gets hammered in by the plunger clamp, it is a simple fix to replace the sacrificial bolt-in sleeve retainer. Washboarding The next three failure modes are less common, but happen nonetheless. They are: pulsation wear or "washboarding" in the fl uid end at the packing on the packing bore, and at the D-rings around the suc- tion and discharge plugs. Leakage through a wear ring (or series of rings in the case of packing wash- boarding) may occur in the suction or discharge bores. The remedy (again) is costly weld repair and up to two months downtime. Experience shows these welds are further away from the intersecting bore and usually last the remaining expected life of the fl uid end. Kerr Pumps' answer to this failure is to Transfer the Wear™ to a sacrificial suction or discharge cap (or removable stuffing box sleeve), away from the expensive fluid end. Transferring wear is the primary way a Frac 1 CONNECT™ fluid end extends its useful operating life and reduces Total Cost of Ownership. The Economic Differences Solving the fi rst fi ve failure modes incrementally extended fl uid ends' useful operating life. These plus the next weakest links (sixth and seventh failure modes) collectively inspired Kerr Pumps to develop, design and deploy the Frac 1 CONNECT™ fl uid end. The frac industry is still recovering from its worst recorded downturn. Pressure pumpers and their cus- tomers demand more efficient fracs driven by new technologies at a lower price. Kerr Pumps accepted that challenge and delivered its Frac 1 CONNECT™ with greater reliability (longer MTBM and MTBF) to reduce TCO and NPT. n Transfer the Wear™ to a sacrifi cial consumable Transfer the Wear™ Super Seal™ Technology

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