A Data-Gathering System To Optimize Production Operations: A 14-Year Overview
Authors: Bucaram S.M. , Yeary B.J. 
Published: December 2007

This paper gives an overview of failure rates, failure costs, failure-control costs, and methods used to reduce in-hole equipment failure.

Introduction

To optimize operations by a failure-control program, basic information is required to define the nature and magnitude of problems and to estimate the economic stakes. Systems for obtaining this information 1–5 have the following goals in common:to determine the cause of equipment failure,to help set specifications for equipment,to predict the future performance of equipment, andto follow the economic impact of remedial actions.

We have had such a system in operation since 1969.6 The Equipment Performance Systems data bank has more than 181,000 records, 115,000 of which are downhole failures of some type. This paper's purpose is to summarize findings derived from the analysis of these failure records. During the 14-year period since implementation of our program, downhole performance has improved program, downhole performance has improved significantly. Average time between rod failures increased from 19 to 43 months-, time between any downhole failure in active wells increased from 12 to 21 months. Performance did not increase just because better records were Performance did not increase just because better records were kept, but because problems were identified and action was taken.

Equipment Performance System-Downhole

Report Form. Our Equipment Performance System uses a multiple-choice form to collect data on failures. These data are computer-Processed to create well histories that are reported in a format designed for easy review. Fig. 1 shows the form that has evolved over the 14 years. This is a three-copy form-one is used for processing, the others for field files. The form has four parts. The top section describes the property, well, and date of the event. The subdistrict code property, well, and date of the event. The subdistrict code specifies a group of properties that are assigned to a specific foreman or production supervisor. The next section describes the event, the cause of the event, and the outcome. The choices available are heavily slanted toward subsurface equipment. The bottom section is concerned with costs. This system is not intended as an accounting tool, and costs are expected to be in approximate whole dollars. The accuracy of the cost information is improved by use of cost data obtained from our purchasing and accounting departments. A distinction is made between subsurface-pump repair costs and all other costs, because pump repairs are performed when the pump is out of the well at any time, not performed when the pump is out of the well at any time, not just for pump failures. Separate pump-repair costs indicate that maintenance was performed on the pump.

Data Reporting.

The data bank is updated with incoming information once a month. and at that time a report is printed and sent to field production and engineering printed and sent to field production and engineering personnel. A sample report page is shown in Fig. 2. personnel. A sample report page is shown in Fig. 2. Problem-well lists are generated once a month-, these are reviewed Problem-well lists are generated once a month-, these are reviewed by field production and engineering personnel, staff production engineers, and personnel associated with chemical production engineers, and personnel associated with chemical treating. Fig. 3 describes problem wells that have had the following problems in the previous 12 months: two or more rod-pump failures, three or more piston-type hydraulic-pump failures, a submersible-pumped well with pump runs of less than I year, two rod-body breaks, two pump runs of less than I year, two rod-body breaks, two rod-pin and/or coupling failures, two tubing failures, or any combination of three failures in I year.

Failure-Control Approaches.

By 1971, it had been determined that at least 66% of all the in-hole failures were caused by corrosion or by equipment mishandling. Efforts were begun to remedy these problems. Seminars addressing mishandling were conducted for our field personnel and for pulling-unit contractors. These seminars dealt with proper selection and handling of inhole equipment, corrosion-inhibition methods, and the economics of equipment-failure control. To design corrosion-control programs, it was necessary to analyze failure data of wells that, because of number and pattern of failures, were probable candidates. Production and engineering personnel revised the lists Production and engineering personnel revised the lists according to their knowledge and experience. To decide whether to include a particular well in the program, we determined whether the cost of failure justified the cost of treatment. Generally, if a producing well was corrosive, it was chemically treated for corrosion.

JPT

p. 457