PCS Ferguson 8000 Series Manual

The 8000 Series® brand is trademarked by PCS Ferguson®.
These documents and materials are copyrighted by PCS Ferguson.
Single Well Plunger Lift Controller Manual
For information contact:
PCS Ferguson 3771 Eureka Way Frederick, CO 80516
Phone: 720-407-3550
Fax: 720-407-3540
Email: information@pcsferguson.com
Website: www.doverals.com/pcsferguson
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Single Well Plunger Lift Controller Manual
1 Contents
1 Understanding Plunger Lift
Operations .......................................................8
1.1 Components ..........................................................8
1.2 Plunger Lift Cycle .....................................................10
1.2.1 Basic Modes of the Plunger Cycle ................................................10
1.2.2 Conditional Modes of the Plunger Cycle ...........................................10
1.3 Optimization Programs, Production Methods, and Set
Points ..............................................................11
1.4 Time Method ........................................................12
1.4.1 Time Set Points and the Basic Plunger Cycle ........................................12
1.4.2 Pressure Set Points and the Time Method ..........................................13
1.4.3 Other Conditional Modes and Set Points ...........................................13
1.5 Pressure Methods ....................................................14
1.6 Automatic Adjustment for Plunger Arrival ...................................15
1.6.1 AutoCycle Program ...........................................................15
1.6.2 Plunger Arrival Windows .......................................................16
1.6.3 Plunger Arrival Counts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
1.6.4 Automatic Time Adjustments ....................................................22
1.6.5 AutoCycle Pressure Set Points ...................................................23
1.6.6 Automatic Adjustment of Pressure Set Points .......................................24
2 Set Points for Plunger Lift
Operations ......................................................26
2.1 Control Production Modes ..............................................26
2.1.1 Fall Time (All Production Methods) ...............................................27
2.1.2 Close Time (All Production Methods) ..............................................27
2.1.3 A Open Time (All Production Methods) .............................................28
2.1.4 Sales Time (All Production Methods) ..............................................28
2.1.5 Delay Close Time (Pressure methods) .............................................28
2.1.6 Mandatory Shut-In Time (All Production Methods) ....................................29
2.1.7 Casing Peak Pressure Time (Pressure methods) .....................................29
2.1.8 High Line Pressure Shut-In Delay (All Production Methods) .............................30
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2.1.9 B Open Time (All Production Methods) ............................................30
2.1.10 B Delay Time (All Production Methods) ...........................................31
2.1.11 Differential Open Pressure (Pressure methods) .....................................31
2.1.12 Load Factor (Fluid Slug) (Pressure methods) .......................................31
2.1.13 Casing Drop Pressure (Pressure Methods). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
2.2 Control Exit of SALES Mode (Pressure Methods Only) ..........................34
2.2.1 D.I.P. Close Pressure (Pressure Methods) ..........................................35
2.2.2 Gas Low Flow Close Rate (Pressure Methods) .......................................35
2.2.3 Critical Flow Constant (Pressure Methods) .........................................35
2.3 Control Shut-In .......................................................36
2.3.1 Low Line Pressure (All Production Methods) ........................................36
2.3.2 High Line Pressure (All Production Methods) ........................................36
3 Set Points for the AutoCycle™
Program ........................................................37
3.1 Overview of Arrival Windows ............................................37
3.1.1 Reset Defaults Button .........................................................38
3.2 Early Window Area ....................................................38
3.2.1 Enable Early Arrival Option .....................................................38
3.2.2 Hr Min Sec in the Early Window area. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
3.2.3 Initial Count in the Early Window area .............................................38
3.2.4 Current Count in the Early Window area ...........................................39
3.3 Fast Window Area .....................................................39
3.3.1 (Fast Plunger Time) (Hr Min Sec) .................................................39
3.3.2 Initial in the Fast Window area ..................................................39
3.3.3 Current in the Fast Window area .................................................40
3.3.4 History (Read Only) ...........................................................40
3.3.5 Deduct from Off-Time in Fast Window .............................................40
3.3.6 Add to Afterflow in Fast Window area .............................................40
3.4 Good Window Area ....................................................41
3.4.1 No Label (Hr Min Sec) .........................................................41
3.4.2 Initial in the Good Window area ..................................................41
3.4.3 Current in the Good Window area ................................................41
3.4.4 (History Read Only) ..........................................................42
3.4.5 Current Afterflow in the Good Window area .........................................42
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Single Well Plunger Lift Controller Manual
3.4.6 Current Off-Time .............................................................42
3.4.7 Min Off-Time ...............................................................43
3.4.8 Min Afterflow ...............................................................43
3.4.9 Max Afterflow ...............................................................43
3.5 Slow Window Area ....................................................44
3.5.1 Current On-Time .............................................................44
3.5.2 Initial in the Slow Window area ..................................................44
3.5.3 Current in the Slow Window area ................................................44
3.5.4 (History Read-Only) ..........................................................45
3.5.5 Deduct from Afterflow in Slow Window ............................................45
3.5.6 Add to Off-Time .............................................................45
3.6 No Plunger Area ......................................................46
3.6.1 Initial in the No Plunger area ....................................................46
3.6.2 Current in the No Plunger area ..................................................46
3.6.3 (History Read-Only) ...........................................................46
3.6.4 Add to Off-Time in the No Plunger area ............................................46
3.6.5 Max Off-Time in the No Plunger Area .............................................46
3.7 Pressure Overrides ....................................................47
3.7.1 Open Tubing Valve (Production Valve) If Area ........................................47
3.7.2 Close Tubing Valve (A Valve) If Area ...............................................47
3.7.3 Plunger Open Adjustments .....................................................48
3.7.4 Plunger Close Adjustments Area .................................................48
3.7.5 Safety Shut-Down (PSIG) Area. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49
3.8 Controls for Operations .................................................49
3.8.1 Options for controlling adjustments ...............................................49
3.9 Activity History (Read-only) ..............................................49
4 8000 Series Walkup Display and Keypad Commands ...................50
4.1 Basic Key Sequences ..................................................50
4.2 The Single-Well™ Application Keypad Commands .............................52
4.3 The AutoCycle™ Program Keypad Commands
(Single-Well only) ........................................................53
5 Understanding Well Site
Communications .................................................56
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5.1 On Site Communication with an 8000 Series Controller ........................56
5.2 Off Site Communication with an 8000 Series Controller ........................57
5.3 Well Networks .......................................................58
5.3.1 Well System Components ......................................................58
5.3.2 The 8000 Series Controllers on a Well Network ......................................58
5.3.3 Wireless Communications ......................................................59
5.3.4 Wired Communications ........................................................60
5.4 Security Access Codes .................................................60
6 Monitoring Tank Levels ..........................................62
6.1 Understanding the Tank Management System ...............................62
6.1.1 System Settings .............................................................62
6.1.2 Tank Settings ...............................................................63
6.1.3 Alarms and Shut-Ins ..........................................................64
6.1.4 Polling Interval ..............................................................65
6.1.5 The Tank Configuration File .....................................................65
6.2 Preparation .........................................................66
6.3 Task List for Tank Management ..........................................66
6.4 Configure Tanks ......................................................66
6.4.1 Importing an OleumTech or iLevel Tank configuration file ..............................67
6.4.2 Configuring Tanks in the WellVision Application ......................................67
6.5 Tank System Configuration ..............................................69
6.6 Monitoring Levels in the Tanks ...........................................70
6.6.1 Review Current Status ........................................................70
6.6.2 Review Tank Trends ..........................................................71
6.6.3 Respond to Tank Level Alarms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74
7 Viewing Graphs of Well
Performance ....................................................76
7.1 Preparation .........................................................76
7.2 General Task List .....................................................76
7.3 View a Basic Well Trending Graph .........................................77
7.4 View a Summary of Data within a Timeframe ................................79
7.5 View Details and Calculations within a Timeframe ............................80
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Single Well Plunger Lift Controller Manual
Appendix A: Single Well I/O Worksheet ................................83
Appendix B: 8000 Series® Agency Approval ............................84
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Single Well Plunger Lift Controller Manual
Revision History
Date Description Version
6/1/2017 Initial Release 1.0
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Single Well Plunger Lift Controller Manual
1 Understanding Plunger Lift
Operations
Over time, a well’s gas production declines but a plunger lift system can increase a well’s productivity and life span. The natural pressure that lifts the gas from the well to the surface declines. Liquids collect in the wellbore or tubing and reduce the gas ow. If the liquids remain in the well, they eventually stop the gas ow. A plunger system lifts the liquids out of the well. Deliquication optimizes gas production and increases the life span of the well.
This chapter describes basic components of a plunger lift system, plunger lift functions, and your role in the operations. For more information about conguring a well program.
1.1 Components
The well system components of plunger lift operations are:
Plunger Components
Plunger that acts as a well-bore swab
Lubricator that catches the plunger when it surfaces and provides access for maintenance
Arrival sensor that indicates when the plunger has surfaced
Bottom hole bumper spring that cushions the plunger’s fall
Plunger Cycle Control
• Motor valve, a pneumatic valve, that controls gas ow
• Production valve , a solenoid valve, that controls the motor valve
• Controller that uses a Well Program to control the production valve
• User interface such as the WellVision™ application, the WellTrekker™ application, or the Walk Up Display to direct the controller
Analog and digital devices that provide data inputs the controller monitors
Sales line pressure sensor
Tubing pressure sensor
Casing pressure sensor
Other devices
• [Optional] Tank valve a solenoid valve for a vent that can relieve backpressure on the Sales Line and assist the plunger cycle
Production on Site (provided by the site owner)
• Sales line
• Separator that separates gas, oil, and water
• Tank that stores the liquids removed by the plunger
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Understanding Plunger Lift Operations
Single Well Plunger Lift Controller Manual
Figure 1.1 The basic components of the Plunger Lift System in place
Understanding Plunger Lift Operations
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Single Well Plunger Lift Controller Manual
1.2 Plunger Lift Cycle
The plunger system lifts the liquids using pressure from the gas ow. The plunger moves between the bottom hole bumper spring and the lubricator at the top of the well. The Motor Valve controls physical ow of the gas. The production valve controls when the Motor Valve is open and closed. When the production valve is closed, the gas ow is off. The plunger falls down the well, through the liquid, and to the bottom hole bumper spring. When the production valve is open, the gas ow is on. The natural pressure from the gas ow lifts the plunger. The liquids move ahead of the plunger, out of the well, and into a separator or directly into the tanks. The separator directs gas into the Sales line, oil to an oil tank, and water to a water tank.
The controller uses a Well Program to direct the components through the plunger cycle. The plunger cycle has modes. The Well Program species the modes used during the cycle. Using the Well Program, the controller optimizes production in response to the well conditions. The Well Program has production methods to simplify conguration of optimization. The user chooses a production method and enters set points to create a Well Program.
The following paragraphs describe the modes and production methods that the Well Program uses to optimize production.
1.2.1 Basic Modes of the Plunger Cycle
The plunger cycle has basic modes: FALL, CLOSE, A OPEN, and SALES. During FALL mode, the plunger returns to the bottom of the well. During CLOSE mode, the pressures build in the well. The well is not producing gas. During A OPEN mode, the plunger rises to the top with the liquids. After the plunger arrives, the Well Program uses SALES mode to produce gas.
The modes that the Well Program uses depend on the arrival of the plunger, on the production method, and set points. An arrival sensor detects the surfacing of the plunger. The controller monitors this sensor and other input devices. The controller compares the data inputs with the set points specied by the user in the Well Program. In the basic scenario for the Time method, after the plunger arrives, the controller directs the Well Program into SALES mode.
Each mode has primary set points and a group of secondary set points. The basic set points are periods of time or pressure values. Additional set points are values used in a calculation. The production method determines which set points the Well Program uses to exit and enter modes. For a basic example, the primary set points for the Time Method are Fall Time, Close Time, A Open Time, and Sales Time.
1.2.2 Conditional Modes of the Plunger Cycle
The controller and Well Program can respond automatically to well conditions. The well conditions affect the arrival of the plunger. A Well Program has a group of secondary set points that specify conditional modes: Line Delay, Mandatory Shut-In, B Open, and B Delay. These set points allow the plunger lift system to respond to the conditions of the well. The production method species which set points the controller uses to respond to well conditions.
To optimize production in response to well conditions, the Well Program has modes for using delay, shut-in, and the Tank Valve. Not all well systems have a Tank Valve, but a Well Program can use it to optimize production.
For an example of a delay, the basic mode, A OPEN, is a xed time, A Open Time. However, well conditions can slow the arrival of the plunger. If the Well Program species the set point, Delay Close, the controller can allow production beyond the time set for A OPEN mode. The plunger does not arrive but gas continues to ow and the plunger continues to rise.
To close production in response to conditions, the system has a MANDATORY SHUT-IN mode.
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Understanding Plunger Lift Operations
Single Well Plunger Lift Controller Manual
The primary set point for this mode is a time setting. However, the controller can use a pressure setting on the Casing to enter this mode. For example, if the plunger does not arrive during the time specied for the set point, A Open, the controller counts down the time interval specied by the set point and detects that the pressure on the casing is lower. After that time, the Well Program enters Mandatory Shut-in mode and production stops so that pressure can build to raise the plunger on the next plunger cycle.
1.3 Optimization Programs, Production Methods, and Set Points
The user can specify a Well Program in the WellVision application. Using the information unique to the well, the user chooses a production method and species the set points. The controller uses this Well Program to evaluate the data inputs and direct operations.
The Well Program can include the following factors to adjust production. These factors apply to every production method.
Constant factors
• Tubing depth
• Tubing diameter
• Plunger type or style
Variable factors
• Sales line pressure
• Production ratio of gas-to-liquid
Some set points are common to all of the methods. These set points close the well to protect the gas lines from damage or can respond to possible damage.
For example, to monitor backpressure and protect the sales line, each method includes the following set points for that line:
High Line Shut-in Pressure: The maximum pressure that the program allows on the line before
automatically closing. To prevent shut-in due to momentary spikes in pressure, the user can specify a delay time.
High Line Pressure Shut-in Delay time: A period of time the controller samples the pressure.
The controller uses the samples to decide if a high reading is temporary or steady. If temporary, production can continue. If steady, the program closes the well.
Low Line Shut-in Pressure: The minimum pressure the program allows on the line before
automatically closing the well.
NOTE Best Practice Always enter values for these set points to protect the
Sales Line. These settings can prevent ruptures or close the well in the case of a rupture. Also, set the Notifications tool to send a text or an email in response to alarms. For more information about the Notifications
tool.
Understanding Plunger Lift Operations
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Single Well Plunger Lift Controller Manual
The
user can choose from several production methods. Each method employs specic primary set points and a group of associated set points. These set points allow the user to customize movement between the modes in response to well conditions.
The user can disable any set point by entering zero or a value too high to occur. (Zero time is 00:00:00: zero pressure is 0: high time is 99:59:59: and high pressure depends on the gauge).
The WellVision and WellTrekker applications offer the following production methods to optimize a well with the Plunger Lift System:
• Time method
• AutoCycle
• Casing pressure minus Tubing pressure
• Casing pressure minus Line pressure
• Tubing pressure minus Line pressure
The following paragraphs describe the methods and their set points.
1.4 Time Method
Using the Time method, the controller manages the well using set points of time. The times for FALL, A OPEN, CLOSE, and SALES modes repeat for every plunger cycle. The Well Program offers additional set points to respond to well conditions. The following sections describe how the controller and the Well Program work together through the basic and conditional modes of the plunger cycle.
1.4.1 Time Set Points and the Basic Plunger Cycle
A basic Well Program, that uses the time method, moves through the following modes using plunger arrival and time countdowns.
The controller closes the production valve and the Well Program enters the FALL mode. During FALL mode, the plunger drops. The controller counts down the time specied for Fall Time. The Well Program enters CLOSE mode. The controller counts down the time specied for Close Time. During the CLOSE mode, pressure builds in the well. The Controller monitors the data coming from the pressure sensors. However, the Well Program using a Time method does not use pressure readings to change modes. The controller continues to monitor pressures and the Well Program can use pressure settings to override the time settings.
After the Close Time expires, the Well Program enters A OPEN mode and opens the production valve. The controller counts down the time set in A Open Time. This setting should match the time the plunger usually takes to come up the wellbore and remove the liquids. The arrival sensor detects the surfacing of the plunger. The controller directs the Well Program to enter SALES mode. The controller counts down the time set in Sales Time. After the Sales Time expires, the controller directs the Well Program to enter FALL mode and closes the production valve. The process repeats. If the Sales Time is zero (00:00:00), the Well Program enters FALL mode. The user can turn off any set point for time with a value of zero (00:00:00).
1.4.2 Pressure Set Points and the Time Method
If the user species the set points for high and low line pressure, the Well Program responds to the pressure settings by entering DELAY CLOSE mode. The sequence of the modes depends on when
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Understanding Plunger Lift Operations
the controller detected the High Line Shut-In pressure and the results of the sampling during the time set in High Line Pressure Shut-in Delay.
If the pressure sampling reveals the pressure temporarily spiked and then fell, the Well Program returns to the previous mode. The controller continues to count down the time set for that mode
during the delay. The delay does not change the duration of A OPEN mode or SALES mode. If the sampling reveals a possible problem, the Well Program closes the well and enters FALL mode. Well conditions change and the changes affect the plunger arrival. To respond to variations in the plunger’s arrival, the user can specify additional set points in the Well Program.
1.4.3 Other Conditional Modes and Set Points
The plunger might not surface as expected during A OPEN mode. The ow might be too low to raise the plunger or excessive backpressure might be the issue. To raise the plunger, the program must close the production valve for a time to build pressure or the system must relieve excessive backpressure through a Tank valve.
Respond to no plunger by closing Production Valve
To close the production valve, the Well Program offers a set point, Mandatory Shut-in Time. After the A Open time expires, the controller checks for data from the arrival sensor. If the controller cannot verify arrival and the program provides a Mandatory Shut-In time, the controller directs the program into MANDATORY mode and counts down the time. After the time expires, the Well
Program enters FALL mode.
Single Well Plunger Lift Controller Manual
Respond to no plunger by opening Tank Valve
If the system has a Tank valve, the controller can direct the valve to open and vent the backpressure. With the backpressure relieved, the ow might raise the plunger and the sensor can
detect the arrival.
NOTE To add this response to the program, the user specifies a B Open Time.
After the plunger arrives and the time expires, the Well Program enters B DELAY mode. The program uses the B Delay Time before entering SALES mode. The controller counts down the Sales Time. The program enters FALL mode. The cycle repeats.
If the ow cannot raise the plunger with the backpressure released, then the program enters MANDATORY SHUT-IN mode. The controller counts down the Mandatory Shut-In time. When the
controller detects the required pressure, the program enters OPEN mode. The cycle repeats.
1.5 Pressure Methods
A well analysis might indicate that pressures instead of time would optimize production more effectively. The user can choose a production method that uses pressure differentials. The WellVision and WellTrekker applications offer the following calculations as methods.
Casing pressure minus Tubing pressure
Casing pressure minus Line pressure
Tubing pressure minus Line pressure
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Single Well Plunger Lift Controller Manual
For each of these methods, the user species a differential in pressure based on the well’s conditions. The primary set point is Differential Open Pressure. The set point answers the question: “At what pressure difference, does the user want the Well Program to enter A OPEN mode?” Time still plays a role as the controller counts down Fall Time before evaluating the pressure differential. After the Fall Time expires, the controller evaluates the pressures. If the difference meets pressure criteria specied by the set points shown as a delta p (∆p), then the Well Program enters A OPEN mode.
Basis for differential Well opens if: Well example
Casing pressure–Line pressure
Tubing pressure–Line pressure
Casing Pressure–Tubing pressure
Table 1.1 Production Methods and Pressure Differential
Difference in pressure is greater than (>) the setting
Difference in pressure is greater than (>) the setting
Difference in pressure is less than (<) the setting
Most well configurations
Well with a packer and no annular pressure
Well with slow building casing pressures
NOTE For more information about the pressure methods, see “Configuring a
Single Well” section.
1.6 Automatic Adjustment for Plunger Arrival
The AutoCycle program provides automatic adjustments using the plunger arrival and number of arrivals. Using the AutoCycle program, a Well Program uses initial settings, monitors the arrival of the plunger, and adjusts time or pressure settings. These adjustments ne-tune the production cycle for optimum plunger speed, liquid removal, and well performance.
For this method, the controller monitors and records data about the arrival of the plunger. The Well Program uses the AutoCycle program to respond with adjustments immediately.
1.6.1 AutoCycle Program
The AutoCycle program uses the plunger speed to optimize production. The user provides values for a set of arrival times. These values depend on the specic well. The arrival times indicate to the AutoCycle program the speed of the plunger. Given the depth of the well and the arrival time, the AutoCycle program calculates the speed by dividing the depth by the arrival time.
Maintaining an appropriate speed is critical to the production and safety of the well. Plungers that arrive too fast can damage wellhead components at the surface. This damage might lead to failure. Plungers that arrive too slowly might indicate that pressures are falling. The pressure might be too low to raise the plunger. To optimize production, the AutoCycle program uses a set of arrival windows. Each window type has a set of counters and a set of adjustments.
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Understanding Plunger Lift Operations
The following gure shows the basic plunger cycle and where the AutoCycle program windows affect production.
The following paragraphs provide more detail about the windows and their associated parameters.
1.6.2 Plunger Arrival Windows
The AutoCycle program makes the same adjustments to the Afterow Time and Off Time that an on-site operator would make while tending the well. The AutoCycle program compares the actual time of arrival with the values of the set points for the windows.
Single Well Plunger Lift Controller Manual
Figure 1.2 Arrival Windows of the AutoCycle program
This comparison identies the speed of the plunger and the category of arrival. Using this comparison, the AutoCycle program makes adjustments as described in the table below:
Plunger arrival Adjustments applied
Good None, within this window of time, the AutoCycle program does not make adjustments. However,
the program does identify minimum and maximum and maximum times. This arrival indicates best production of the well with an ideal arrival time. The depth of well divided by 800 equals the low limit of Good window. The depth of well divided by 600 equals the upper limit of Good window.
Fast Decrease down hole pressure: within this window of time, the plunger arrives too quickly. The
AutoCycle program deducts from the Fall Time/Close Time (Off Time) and/or adds to the Sales Time (Afterflow time).
Slow Increase down hole pressure: within this window of time, the plunger has arrived too slowly. This
indicates that the down hole pressure was too low. The AutoCycle program deducts from the Sales Time (Afterflow time) and/or adds to the Fall Time/Close Time (Off Time). The user can set options for No Afterflow on Slow Arrivals. The depth of well divided by 270 equals the upper limit of slow window.
No Increase down hole pressure if the plunger fails to arrive at the surface. The AutoCycle program
deducts from the Sales Time (Afterflow time) and adds to the Fall Time/Close Time (Off Time).
No arrival might indicate well problems. If the plunger fails to arrive multiple times, The AutoCycle program informs the controller: the Well Program enters FALL mode and the well is shut-in. The controller raises a Plunger Error. The user needs to clear the error before production can resume.
Table 1.2 AutoCycle Plunger Arrival Window Definitions
Understanding Plunger Lift Operations
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Single Well Plunger Lift Controller Manual
The user provides set points for times typical to the well. These set points dene the windows of time so that the AutoCycle program can adjust the settings correctly. The arrival windows are dependent on the amount of time it takes for the plunger to reach the surface after the production valve (Tubing Valve) is open.
The gure below shows the area of the AutoCycle tab that species the values for evaluating plunger speed.
Figure 1.3 The set points in the Arrival Windows area on the AutoCycle program tab
The user provides the values for the plunger arrival times. The arrival time indicates the rate of speed. If the user knows the depth of the well, the user can specify the well information for the AutoCycle program. Given the depth of the well and the arrival time, the AutoCycle program calculates the speed by dividing the depth by the arrival time. (Distance/Time = Speed) Maintaining an appropriate speed is critical to the production and safety of the well.
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Single Well Plunger Lift Controller Manual
The gure below shows the AutoCycle tab. The user can accept default values that are based on a depth of 8000 feet. The program can meet any level of control the user might want to apply. The user can supply an initial set of times specic to the well and allow the AutoCycle program to adjust automatically. Or the user can enter adjustments.
Figure 1.4 The AutoCycle Tab
To tailor the program to the well, the program has counters the user can change to match the characteristics of the well. The following section describes the counters and the section after that describes the adjustments.
1.6.3 Plunger Arrival Counts
The user can adjust the AutoCycle program by providing arrival counts that are associated with each window. Each window has an initial and a current counter.
The Initial species the number of arrivals to match before the program responds. This count
remains at the default value until the user changes it. The program does not adjust this number.
The Current counter displays the number of remaining arrivals required to trigger a mode
change. This counter reduces the value by one for each arrival in the window. When this counter equals zero (0), the program changes to the mode appropriate for the type of arrival.
The counts that close the well require the arrivals to be consecutive such as Early, Slow, or No Plunger. Requiring consecutive arrivals keeps the well open despite occasional plunger errors but triggers a shut-in for a pattern of errors. The counts that move the well program from A OPEN to SALES (AFTERFLOW) are nonconsecutive such as Fast and Good. The nonconsecutive counts allow the well to produce for Fast or Good arrivals without interruption.
Understanding Plunger Lift Operations
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Single Well Plunger Lift Controller Manual
The counters for Slow and No Plunger reset to the initial value immediately upon a Fast or Good arrival. The Early counter resets upon a Slow or No Plunger arrival. The counters for Fast and Good arrivals reset upon a Slow or No Plunger arrival.
The user needs to know the characteristics and pressures of the well to set the counts appropriately. No single set of values works for all scenarios. The default values are a basic set to begin operations.
Figure 1.5 The Default Values for Counts
Notice that the counts for the Fast Window are both zero (0). With these values, a Slow or No Plunger resets the Current to the Initial. Zero (0) triggers the SALES (AFTERFLOW) mode with the time adjustments for the Fast window. Therefore, a Fast Plunger always moves the program into SALES (AFTERFLOW) mode.
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Single Well Plunger Lift Controller Manual
The same is true for the Good window default values. Notice that good arrivals have associated set points and not adjustments.
Current Afterow (Sales Time)
Current Off-Time (Close Time)
Min Off-Time (Fall Time)
Max and Min limits on Afterow
Notice that the counts for the Slow window are equal at ve (5). After ve (5) consecutive Slow arrivals, the Current count is zero (0) and the program enters CLOSE mode. The program applies the time adjustments to inuence the next cycle toward a Good arrival.
As long as the arrivals are in the Slow window, the program adds to the Off-Time (Close Time) and deducts from the Afterow time (Sales Time) of the next cycle. The program continues to adjust the times until the plunger arrives in either a Good or Fast window. This change resets the Slow Count from zero (0) to the Initial count of ve (5). The program continues to evaluate the arrivals and apply adjustments based on the arrival type and the counts.
The following table summarizes the description of the counts:
For the
window…
Early Consecutive Any other arrival type CLOSE
Fast Nonconsecutive Any Slow or No arrival SALES
Good Nonconsecutive Any Slow or No arrival SALES
Slow Consecutive Nonconsecutive and Fast or Good
No Plunger Consecutive Any Fast or Good arrival CLOSE * Unless the Enable Afterflow on Slow is selected on the AutoCycle tab
Table 1.3 Plunger Counts and Arrival Windows
Current shows # that
are… Current Resets to Initial on…
Mode triggered
when Current = 0
CLOSE*
arrival
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Single Well Plunger Lift Controller Manual
The following section describes the adjustments for the arrival windows and the set points of the Good Window.
1.6.4 Automatic Time Adjustments
The AutoCycle program compares the actual time of arrival with the values of the window set points. This comparison identies the speed of the plunger and the category of arrival. The program applies the adjustments to the Afterow (Sales) time or the Off-Time (Close) if the plunger arrival is outside the Good Arrival window and the count for the window is zero (0). The adjustments can increase or decrease pressure to control the plunger speed. The Fast, Slow, and No Plunger windows have adjustment set points the user can specify.
Afterow (Sales) Afterow (Sales) relieves pressure after the plunger arrives. Shorter
Afterow (Sales) relieves less pressure for the next Tubing On (Open) mode while longer Afterow cycles relieve more pressure. Less pressure slows speed and increases time it takes for the plunger to arrive.
Current Off-Time Adjustments Tubing Off cycles allow pressure to build in order to lift the
plunger and liquids to the surface. Longer Tubing Off (Close) modes result in more pressure buildup: shorter Tubing Off (Close) modes result in less pressure buildup. More pressure increase speed of the plunger and decreases the time it takes for the plunger to arrive.
Figure 1.6 Section of the AutoCycle tab for reading or specifying adjustments
Smaller Time Adjustments
The user can set the AutoCycle program to make proportional adjustments. Proportional adjustments are partial adjustments based on how far the plunger arrival is from the Good Arrival time.
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Understanding Plunger Lift Operations
NOTE Best Practice If the arrival time is very close to the Good Arrival
window use the option for proportional adjustment.
1.6.5 AutoCycle Pressure Set Points
The user can set the program to respond to pressure readings by using the Pressure Overrides feature. The user can specify pressure set points or differentials that move the program from A OPEN mode to AFTERFLOW (SALES) mode or to CLOSE mode.
The adjustments for the Casing Pressure, Tubing Pressure, and Differential Pressure Overrides on Fast, Slow, and No Arrivals are available.
The user can specify pressure set points that change the mode of the AutoCycle program under certain conditions. The following lists summarize the pressure conditions that trigger the production value (Tubing Valve) to open or close.
Open Production Valve (Tubing Valve) Overrides
If Casing pressure is greater than or equal to the set point
Casing Pressure >=
Single Well Plunger Lift Controller Manual
If Tubing pressure is greater than or equal to the set point
Tubing Pressure >=
If the differential of Tubing pressure and Line pressure is greater than or equal to the set point
Tubing Pressure – Line Pressure >=
Casing Pressure – Line Pressure >=
Casing Pressure – Tubing Pressure <=
Fluid Slug <= Casing Pressure – Tubing Pressure / Casing Pressure – Line Pressure
Close Production Valve (Tubing Valve) Overrides
If Casing pressure is less than or equal to the set point
Casing Pressure <=
If Tubing pressure is less than or equal to the set point
Tubing Pressure <=
If Line pressure is greater than or equal to the set point
Line Pressure >=
A delay time is optional
Shuts in the well until the condition is no longer met
High Line Delay Clear <Casing - Tubing <= (during afterflow)
Flow Rate <= (during afterflow)
Safety Shut-Down
Casing Pressure >=
Tubing Pressure >=
Tubing Pressure >=
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Single Well Plunger Lift Controller Manual
The gure below shows the AutoCycle Pressure Overrides dialog box.
Figure 1.7 The dialog box for pressure set points
By using the pressure overrides, the user sets the program to respond to the current pressure readings in addition to the passing of time.
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Understanding Plunger Lift Operations
1.6.6 Automatic Adjustment of Pressure Set Points
The user can set the program to adjust the pressure set points for the next cycle based on the plunger arrival.
Single Well Plunger Lift Controller Manual
Figure 1.8 Adjustments to Pressures for the Arrival Windows
After the user has enabled the program, the user can analyze the results of the optimization program.
NOTE For more information, see “Well Program Set Points for AutoCycle” in the
Reference section of the Help Documents.
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Single Well Plunger Lift Controller Manual
2 Set Points for Plunger Lift
Operations
The user can analyze the well’s performance over time and ne-tune the production method based on trending data. A user examines a current analysis of a well’s performance to set and adjust the frequency of the plunger cycles based on conditions of the well. The rate of liquid accumulation is unique to each well. Changes to the production valve state control the plunger cycle. An electronic controller at the surface automates the state of the production valve.
NOTE For more information about plunger cycles, see “Understanding Plunger
Lift Operations” in this manual.
NOTE For information about specifying a Well Program, see “Configuring Single
Well Production” in the Guides section of the Help Documents.
This document organizes the set points into control and adjustment categories:
Control Production Modes
Adjustments to Open Pressure Values
Adjustments for Plunger Misses
Control Exit of SALES Mode
Control Shut-in
Control Alarms
The user can specify the following set points to adjust when and how the controller directs the Well Program to respond to well conditions.
2.1 Control Production Modes
The user chooses the set points depending on the well conditions and the production method. For the Time method, if Well Program’s value for sales time is 00:00:00, the controller closes the production valve when the plunger arrives. For a pressure method, the controller opens the production valve in response to wellhead pressures. On the Well Program tab, the WellVision application offers only the set points appropriate for the method. The other set points are visible but gray.
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Set Points for Plunger Lift Operations
Single Well Plunger Lift Controller Manual
Figure 2.1 Program Values area shows the set points available based on the production method
2.1.1 Fall Time (All Production Methods)
Format: HH:MM:SS Typical Value: 1:00:00 Disable Value: 00:00:00
Specify a minimum shut-in time to allow the plunger to fall to the bottom of the well. During Fall Time, the user must use the Go to A open mode on the Status tab of the well or use the ON button on the Walk Up Display to open the well. The controller does not use other set points to direct the well to open during this time.
2.1.2 Close Time (All Production Methods)
Format: HH:MM:SS Typical Value: Time method: 2:00:00: Pressure methods: 00:00:00 Legacy Label: TUBING OFF
Specify a shut-in time that ensures pressure build up in the well to surface the plunger with a liquid load before the controller opens the production valve for the next production cycle.
Usage: For pressure methods, this set point is typically set to 00:00:00 because the controller opens the production valve in response to changes in pressure. If the user wants the production valve to open after time regardless of pressure changes, the user can set the Close Time. If a Close Time is set, the value must be greater or equal (>=) the Fall Time.
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Single Well Plunger Lift Controller Manual
2.1.3 A Open Time (All Production Methods)
Format: HH:MM:SS Typical Value: Time method: 1:00:00 Legacy Label: Open Time, TUBING ON for the Sales valve
Specify the time that the well is open and gas is owing through the production valve. During Open Time, the plunger starts to surface and the well produces its initial head gas. Allow enough timing for the plunger to surface with the liquid load. A zero time setting (00:00:00) leaves the well open indenitely or until a plunger arrival triggers Sales Mode.
2.1.4 Sales Time (All Production Methods)
Format: HH:MM:SS Disable Value: 00:00:00 to close the A Valve on plunger arrival Legacy Label: DELAY TIME, Afterow Time
Specify additional time the controller allows gas ow after the plunger arrival. The countdown starts after the plunger sensor detects the plunger at the wellhead surface.
Usage: Typically, the user sets this value as a backup to close the well if the well conditions do not meet other set points within an appropriate time.
For example, the well’s production might be highest when based on meeting a certain pressure, rate, or other value. Typical set points might be one of the following:
D.I.P Close Pressure
Low Gas Flow Rate
Critical Flow K Factor
NOTE Set the Sales Time higher than the normal time the well is able to sell gas.
2.1.5 Delay Close Time (Pressure methods)
Format: HH:MM:SS Disable Value: Use 00:00:00
Specify the time to wait and evaluate whether an increase in the casing pressure is a brief spike or an actual, sustained increase. This set point is evaluated and effective during SALES MODE only. The user can set this to work with Low Gas Flow Rate also.
NOTE For more information about this set point and the modes, see “Pressure
Set Points and the Time Method” in the “Understanding Plunger Lift
Operations” document of the Concepts section.
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Set Points for Plunger Lift Operations
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