Background:
Are you facing with the following issue?
- Presumed to exist of Free Water on Terminal (FSO) may leading to un-monetized quantity although Water Cut Data from Production Well Test of each well and BS&W Analysis were reported within the Company specification/requirements.
- Doubt with activity and accuracy of data well test
- When you find out that wells are producing severely lower than previous tests or maybe the rate is higher than what was the forecasts says.
- Others issue related with well test
First thing before any judgments about well or reservoir behavior, you should suspect measurement instruments and control system. You need to communicate with instrument and system technicians to find the likely source of error and rectify it. Most of the time you cannot just say the transmitter is wrongly calibrated and all of sudden they find the problem and everything get back on track.
As production engineer, you need to be familiar with production well test management, some standards, and apparatus to be able to check the calibration and communicate with oepartor and/or technicians to find and solve the problem.
Although preferred, continuous direct measurement of well production for use in upstream measurement and allocation is usually not a practical option for most operators. Periodic direct measurement is achievable, however, and can be used for determining applicable well rates. Thus, the periodic direct measurement, or well test, becomes an integral activity in upstream measurement and allocation.
Well testing provides a means of determining the production characteristics of a well. A well test can be conducted for a variety of reasons, including an evaluation of the productive potential of a well (incorporating wellbore flow capacity and reservoir limits), a measurement of the gas–oil ratio (GOR), a means to sample reservoir fluids, or some other specific item (refer to Annex A for a more detailed description of the various well tests for oil and gas wells).
For use in upstream measurement and allocation, a well test is referred to as a production well test and is defined as the fluid measurement of gas, oil, and water from a single well during a specified length of time under controlled operational conditions.
Scope:
This document is to provide an introduction on the application of production well testing for well rate determination in production measurement and allocation.
Production well testing addressed in this document refers to measurement of gas, oil, and water quantities from a single well during a specified length of time under controlled operational conditions.
Objectives:
- To carry out assessment of production well testing;
- To understand current state and gaps of Well Test Management before designing future state;
- To provide recommendations based on identified gaps for future state on Well Test Management (Data-People-Process-Asset) in the aims to Realize the Company on Upstream Operation Excellent in Safe, Reliable and Sustain by apply the continuous improvement;
Purposes:
- For developing the Production Well Test Management – gap analysis protocol/checklist;
- To study the Uncertainty of Data Well Test;
- To evaluate Maintenance of measuring equipments (MPFM & Separator Test);
- To review People and organization including Competency, Schedule, RACI;
- Review and improve Well Test Process/activity – including business process work flow, written policy, procedures, and standard forms/template;
- Recommendations for improvement (current state to future state);
Well Testing Methods
In this document, well testing is a well production testing job to find out production data from each well (oil, water and gas) per day. This data is important for Petroleum Engineers to analyze well and formation as a whole, whether the well is still producing good or requires a well service or workover job to maintain / increase the rate of production.
Well testing is carried out with 2 (two) methods, namely:
1) Manual Well Testing (MWT)
2) Automatic Well Testing (AWT)
Typical Assessment Activity Chart of Well Test
The typical activity flow chart for conducting assessment of well test is given in following figure:
Typical Procedure for Conducting Assessment on Well Test Management
Typical procedure/steps and/or report outline of Assessment on well test is given ass below:
- Background
- Purpose
- Scope
- Definitions
- Procedures and Responsibilities
5.1. Declaring Management Commitment
5.2. Defining Scope of Assessment
5.3. Organizing Assessment Team Member
5.4. Planning and Scheduling Assessment
5.5. Establishing Agenda of Assessment
5.6. Establishing Assessment Protocol and Tool
5.7. Preparing Documentations for Effective Assessment
5.8. Recording Assessment Observation and Findings
5.9. Analyzing Data, Concluding Result, Recommending Improvement
5.10. Developing, Issuing, and Socializing Assessment Report
5.11. Management of Assessment Recommendations
- Verification
- References
- Document Control and Revision Log
- Appendices
Typical Flowchart for Consultant to conduct assessment of Well Test is given below:
References:
Standard Best Practise:
Applicable Standards/Code/Regulationa/Best Practices in upstream oil & gas industry should be referenced for and will be used as the main basis for developing and implementing the Well Test Management, as below:
American Petroleum Institute (API) – Manual of Petroleum Measurement Standards (MPMS):
- Chapter 20.1—Allocation Measurement;
- Chapter 20.2—Production Allocation Measurement Using Single-phase Devices;
- Chapter 20.3—Measurement of Multiphase Flow;
- Chapter 5—Recommended Practice for Application of Production Well Testing in Measurement and Allocation;
- Chapter 8.1, Standard Practice for Manual Sampling of Petroleum and Petroleum Products
- Chapter 11.1, Temperature and Pressure Volume Correction Factors
- API MPMS 5.3 : Metering Measurement of Liquid Hydrocarbon by Turbine Meters, Includes Addendum 1
- API MPMS 14.3.1 : Manual of Petroleum Measurement Standards Chapter 14 Concentric, Square-Edged Orifice Meters Parts 1 – General Equations and Uncertainty Guidelines
American Petroleum Institute (API)
- API 6D :Specification for Pipeline Valves
- API RP 14C : Analysis, design, installation, and testing of basic surface Safety systems for offshore production platforms
- API RP 551 : Process measurement instrumentation
American Gas Association (AGA)
- AGA Report 3 : Orifice metering of natural gas
- AGA Report 5 : Natural gas energy measurement
- AGA Report 8 : Compressibility factor of Natural Gas & Related Hydrocarbon Gases
- AGA Report 9 : Measurement of gas by multipath ultrasonic meters
American Society for Testing and Material (ASTM)
- ASTM D 1085 : Standards method of gauging petroleum and petroleum Products
- ASTM D1796— Standard Test Method for Water and Sediment in Fuel Oils by the Centrifuge Method;
ISO/IEC:
- ISO/IEC 17025 —General requirements for the competence of testing and calibration laboratories;
- ISO/IEC GUIDE 98-3:2008 (EN) —Uncertainty of Measurement;
- ISO 5167-1 : Measurement of fluid flow
- ISO 9001:2015 Quality Management System – Requirements
- Clause 7.2 Competence
- Clause 7.5 Documented information
- Clause 8.1 Operational planning and control
- Clause 7.1.5 : Monitoring and measuring resources
Directive 017 Measurement Requirement for OG, Release date: November 21, 2018 : Directive 017 consolidates, clarifies, and updates Alberta Energy Regulator (AER) requirements for measurement points used for AER accounting and reporting purposes, as well as those measurement points required for upstream petroleum facilities and some downstream pipeline operations under existing regulations.
Measurement Guideline for Upstream Oil and Gas Operations, Version 2.0 : November 2018
Local Regulations:
- Keputusan Menteri Tenaga Kerja Dan Transmigrasi Nomor : KEP. 250/MEN/V/2007 Tentang penetapan standar kompetensi kerja nasional indonesia sektor industri minyak dan gas bumi serta panas bumi sub sektor industri minyak dan gas bumi hulu bidang produksi sub bidang operasi produksi
- PP no 2 th 1989 : standar nasional untuk satuan ukuran
- PTK-062 Manajemen Operasi Produksi Minyak Dan Gas Bumi;
- Pedoman Pelaksanaan Operasi Produksi dan Pelaporan Arus Minyak Dan Gas Bumi (PUPO-PPAM);
- Other relevant documents;
Additional Reading :
- Oil Well Testing Handbook
- Buku PK. TEKNIK PRODUKSI MIGAS Semester 3, terbitan Kementerian Pendidikan dan Kebudayaan Republik Indonesia, th 2013
- Buku PK. PROSES PRODUKSI MIGAS Semester 4, terbitan Kementerian Pendidikan dan Kebudayaan Republik Indonesia, th 2013
- Buku PK. TEKNIK RESERVOIR DAN CADANGAN Semester 3, terbitan Kementerian Pendidikan dan Kebudayaan Republik Indonesia, th 2013
Link/URL – Read More :
- Surface Well Testing: Guidelines for Data verification and Dealing with
Main Issues about Measurement Devices, https://www.linkedin.com/pulse/surface-well-testing-guidelines-data-verification-dealing-sabzi/ , read on 4 Dec 2018. - https://id.wikipedia.org/wiki/Akurasi_dan_presisi
- https://www.astm.org/Standards/D1250.htm
- https://upmforum.com/upm-forum-2018/presentation-lectures/Presentation%20Matt%20Zimmerman.pdf
- https://petrowiki.org/Well_test
- https://www.bcogc.ca/node/8283/download
- https://home.czu.cz/storage/52485_introductory-well-testing.pdf
- https://id.wikipedia.org/wiki/Pencatatan_Sumur
- https://www.coursehero.com/file/24971764/BAB-4-JENIS-JENIS-WELL-TEST-SUMUR-MINYAKdocx/
- https://id.scribd.com/doc/81961868/ANALISIS-UJI-SUMUR
- http://teknik-perminyakan-indonesia.blogspot.com/2015/03/pengujian-bs-w-penting-untuk-crude-oil.html