SSM0019 G. D Aerator SS6000 Liquid Settlement System Flushing Tool User s Manual

Transcription

1 SSM0019 G D Aerator SS6000 Liquid Settlement System Flushing Tool

2 Although all efforts have been made to ensure the accuracy and completeness of the information contained in this document, RST Instruments Ltd., reserves the right to change the information at any time and assumes no liability for its accuracy. Copyright RST Instruments Ltd. All rights reserved. Product: Document title: User s Manual Document number: SSM0019 Revision: G Date: July 02, 2015 Contact Us: Sales information: sales@rstinstruments.com Technical support: rst_support@rstinstruments.com Head Office: Office hours: Kingston St Maple Ridge, BC Canada V2X 0Z5 8:30 am to 5:00 pm Pacific, Monday to Friday (excluding holidays) Telephone: Facsimile: Toll Free: Website: SSM0019 G RST Instruments Ltd. Page ii

3 TABLE OF CONTENTS 1 INTRODUCTION SAFETY PRINCIPLE OF OPERATION Water and Glycol Mixture Liquid Settlement System Arrangement HARDWARE INTERFACE PREPARATION General Preparation Water and Glycol Mixture Female Quick-Connect Jumper Line Preparation Site Preparations for Circulation or Flushing Operations Determination of the Maximum Flushing or Circulating Pressure OPERATION Reservoir Purge Reservoir Refill Circulation and Flushing Procedures MAINTENANCE Standard Maintenance Inspections of Liquid Settlement Systems TROUBLESHOOTING No Flow During Flushing Air Bubbles in the Reservoir Manifold or Twin Tube Lines Leakage in the Twin Tube Lines Blockage in the Twin Tube Lines SERVICE AND REPAIR APPENDIX A VARIOUS COMPONENTS OF LIQUID SETTLEMENT SYSTEMS... A 1 APPENDIX B TIMER CONTROLLER... B 1 APPENDIX C FIELD DATA RECORD SHEET EXAMPLE... C 3 SSM0019 G RST Instruments Ltd. Page iii

4 LIST OF FIGURES Figure 3-1 Typical VW Liquid Settlement System Arrangement... 8 Figure 3-2 Settlement Plate with VW Pressure Transducer... 8 Figure 3-3 Typical Arrangement of Collar Reservoir and Manifold... 9 Figure 4-1 D Aerator Flushing Tool Instrument Panel Figure 4-2 Settlement Cell Flushing Configuration Figure 4-3 D Aerator SS6000 Accessory Items Figure 5-1 Female Quick-Connect Couplings Figure 8-1 B-4TF4-LE Inline Filter & 40micron Element Figure A-1 Various Components of Liquid Settlement Systems... A 1 Figure C-1 Data Record Sheet Example... C 3 LIST OF TABLES Table 4-1 Instrument Panel Description Table 4-2 Settlement Cell Accessory Description SSM0019 G RST Instruments Ltd. Page iv

5 1 INTRODUCTION This manual covers the design, installation, operation, and maintenance of the RST. Liquid settlement systems monitor relative settlement or heave by measuring any changes in elevation between a surface mounted reservoir and a buried settlement plate. The liquid settlement systems contain a de-aired water and glycol mixture that will spoil over time by absorbing atmospheric gases and requires periodic replacement. Previous methods of flushing liquid settlement systems involved transporting large volumes of de-aired water/glycol mixture and introducing the replacement fluid using positive pressure pumping equipment or vacuum pumps. This method was difficult to do correctly, was time consuming, and often did not completely eliminate all dissolved gases within the system. The RST will allow users to complete a full circulation and de-airing of the water and glycol mixture within an entire liquid settlement system in a few hours. The water and glycol mixture is contained within a liquid settlement system and is circulated through a De-Gassing Module which will remove 100% of the dissolved gases contained within the fluid. The tool may also be used to perform a full flush and fluid replacement. The D Aerator SS6000 Flushing Tool is completely portable and selfcontained and only requires minimal field maintenance. This tool must be operated in an extremely specific and precise manner to achieve the required technical results. Failure to do so could easily result in damage to both the flushing tool and the installed settlement system cells and pressure transducers. The instrument operator must be well trained in the correct operation of the tool. Liquid settlement systems are used in many geotechnical and construction applications, such as: Pre-load consolidation monitoring; Construction control of embankments and fills; Subsidence or settlement monitoring; Long-term foundation performance monitoring. 2 SAFETY Avoid damaging the settlement sensor by ensuring that the maximum pressure range for all buried pressure transducers is known and pumping SSM0019 G RST Instruments Ltd. Page 5

6 pressure are set below the maximum allowable value. Establish a maximum circulation pressure prior to starting the flushing tool. The maximum circulation pressure should be a safe range which will not damage the installed pressure transducers. 3 PRINCIPLE OF OPERATION NOTE: THE OPERATOR MUST HAVE A CLEAR UNDERSTANDING OF THE PHYSICAL CONFIGURATION, OPERATION, AND HYDRAULICS OF THE INSTALLED LIQUID SETTLEMENT SYSTEM TO ENSURE CORRECT AND EFFECTIVE CIRCULATION IN A FLUSHING OPERATION. TIME MUST BE SPEND FAMILIARIZING WITH THE FLUSHING TOOL CONFIGURATION AND OPERATION BEFORE PROCEEDING INTO THE FIELD. SHOP TESTING AND TRIALS ARE HIGHLY RECOMMENDED. 3.1 WATER AND GLYCOL MIXTURE The RST liquid settlement systems are filled with a 50/50 mixture of distilled water and 100% industrial grade glycol. Automotive-grade antifreeze is not 100% glycol and contains many chemical additives and should not be used in the liquid settlement system. Glycol is a toxic substance and must be disposed of in an environmentally acceptable manner. The mixture has been de-aired to remove any dissolved gases must be filtered through a 70 micron filter to remove any minute debris. The settlement system is filled under vacuum at the manufacturing facility to ensure the deaired mixture remains gas-free until installation. The mixture also prevents freezing of the lines and microbial or algae growth. The settlement system reservoir is exposed to the atmosphere and will begin to absorb gases upon installation. The gases will slowly permeate downward into the reservoir manifold and into the tops of the individual hydraulic lines. The dissolved gas may reach a saturation point and develop gas bubbles within the hydraulic lines. The gas bubbles will influence the transmission of line pressures resulting in inaccurate readings. The longer that the liquid settlement system is in service without flushing, the more likely gas bubbles will collect in the hydraulic lines and cause potential reading inaccuracies. It is recommended to periodically flush the entire settlement system hydraulic lines with fresh de-aired 50/50 water and glycol mixture in the field with the RST. SSM0019 G RST Instruments Ltd. Page 6

7 NOTE: THE ¼" TWIN PLASTIC TUBING USED FOR LIQUID SETTLEMENT SYSTEMS HAS AN I.D. OF 3 /16" (OR MM). THE FILL VOLUME REQUIRED FOR 10 METERS OF THE TWIN TUBE LINE (20 METERS TOTAL TUBING LENGTH FOR SUPPLY AND RETURN) IS APPROXIMATELY LITRES. 3.2 LIQUID SETTLEMENT SYSTEM ARRANGEMENT A typical liquid settlement system consists of several settlement plates that are connected to a surface-mounted liquid reservoir by twin plastic tube hydraulic lines. A small manifold block is located on the settlement plate which connects the bottom ends of the twin plastic tube hydraulic lines to the pressure transducer. The manifold block allows connection through the twin tube hydraulic lines for full fluid circulation from the collar reservoir and manifold. Each vibrating wire (VW) pressure transducer includes a thermistor for accurate temperature measurement. Refer to Figure 3-1 for a typical liquid settlement system arrangement. Refer to Figure 3-2 for the settlement plate and hydraulic connection configuration. The hydraulic connection to the settlement cell pressure transducer provides detailed pressure information on the vertical depth of the settlement cell below the current reservoir fluid level. The hydraulic pressure exerted by the surface reservoir on the buried pressure transducer is measured as the settlement plate settles or heaves. Strain gauge and vibrating wire transducers are typically used to measure these movements. Settlement is measured relative to the initial readings taken immediately following the installation. Changes in atmospheric conditions and fluid level evaporation can be compensated for by an additional pressure sensor located at or near the surface manifold. Settlement of the reservoir can be easily calibrated based on regular manual survey results. SSM0019 G RST Instruments Ltd. Page 7

8 FIGURE 3-1 TYPICAL VW LIQUID SETTLEMENT SYSTEM ARRANGEMENT FIGURE 3-2 SETTLEMENT PLATE WITH VW PRESSURE TRANSDUCER SSM0019 G RST Instruments Ltd. Page 8

9 FIGURE 3-3 TYPICAL ARRANGEMENT OF COLLAR RESERVOIR AND MANIFOLD A common fluid reservoir and manifold arrangement is located above the buried settlement plates at a stable location above ground. The reservoir and manifold arrangement supply a constant static hydraulic pressure to the multiple settlement cells connected to the manifold. Readings and maintenance work to the liquid settlement system is performed at the fluid reservoir and manifold for each installed system. Refer to Figure 3-3 for the collar reservoir and manifold configuration. Refer to Appendix A for a diagram of a liquid settlement system with different system components to illustrate the variety of equipment options that could be configured for a field application. All variations of liquid settlement systems function according to the same general principles of applied hydraulic pressure from a known reservoir level. SSM0019 G RST Instruments Ltd. Page 9

10 4 HARDWARE INTERFACE The RST is selfcontained within a waterproof molded plastic hard case and is ready for use in the field. Refer to Figure 4-1 for the configuration and description of the instrument panel. FIGURE V DC Charging Port 2 On/Off Switch 3 Timer Controller 4 Low Battery Light 5 Pressure Relief Valve D AERATOR FLUSHING TOOL INSTRUMENT PANEL 6 Pump Pressure Gauge 7 Outlet Quick-Connect 8 Vacuum Gauge 9 Inlet Quick-Connect 10 Fill Quick-Connect The function and operation of the control panel is described in Table 4-1. SSM0019 G RST Instruments Ltd. Page 10

11 TABLE 4-1 INSTRUMENT PANEL DESCRIPTION Component Function Description On/Off Switch Timer Controller Low Battery Light Vacuum Gauge Pressure Gauge Pressure Relief Valve Outlet Quick- Connect Inlet Quick- Connect Used to turn the D Aerator Flushing Tool on and off. Used to set the run time duration for the low volume/low pressure pump and the vacuum pump. Indicates when the available onboard power for full operation has reached its end. Indicates the negative pressure created by the vacuum pump. Indicates the pump pressure being applied to the outlet line. Used to regulate pressure applied to the twin tube plastic lines during the flushing procedure. Connects to one of the ¼ plastic twin tubes attached to the buried settlement plate. Connects to the other ¼ plastic twin tube attached to the buried settlement cell. Turn the switch to the ON position for any function to occur with the flushing tool. Turn the switch to the OFF position to immediately shut down the flushing tool and any systems in operation. Refer to Appendix B for detailed instructions on programming the timer. Re-charge the flushing tool immediately. The 12V DC battery may be damaged should operation of the flushing tool continue past the warning light activation. Normal range during operation is between 24 and 29 inches Hg. Should the vacuum level drop below 20 inches Hg, stop and investigate the vacuum system immediately for problems. Normal circulation pressure is between 3 and 25 psi (21 and 172 kpa) depending on the maximum range of the pressure transducer installed at the settlement cell. Safe operation of the flushing tool is dependent on the correct operation of the pressure relief valve to provide a safe pressure level. All operators must fully understand the flushing procedure and the proper use of the pressure relief valve to control the maximum output pressure. Caution must be exercised to ensure that the maximum pressure range for all buried pressure transducers is known and that a maximum circulation pressure, which will not damage the installed pressure transducer, is established before circulation is started. This connection allows the water and glycol mixture within the ¼ plastic twin tubes to be circulated. This connection allows the circulated water and glycol mixture to enter the flushing tool at atmospheric pressure. Fill Quick- Connect Used to provide a direct atmospheric pressure connection to the inlet quick-connect. Hydraulically attached to the inlet quickconnect. Connected to a 0.1L make-up reservoir which will provide additional water and glycol mix to the system, as required due to the removal of air from the system. Refer to Figure 4-2 for settlement cell flushing configurations. SSM0019 G RST Instruments Ltd. Page 11

12 FIGURE 4-2 SETTLEMENT CELL FLUSHING CONFIGURATION 1 RST D Aerator SS6000 Flushing Tool 2 RST VW2106 Vibrating Wire Readout Unit 3 RST Vibrating Wire 4 Conductor Signal Cable 4 Twin Tube ¼ Plastic Hydraulic Lines with Plastic Jacket 5 ¼ Plastic Hydraulic Jumper Lines with Fittings (2) 6 Settlement Plate with Attached Settlement Cell 7 Manifold Block Attached to Settlement Plate 8 RST VW2100 Vibrating Wire Pressure Transducer 9 Make-Up Reservoir Connected at the Fill Quick-Connect 10 In-Line Filter Connected at the Inlet Quick-Connect 11 Bottle of New 50/50 Water and Glycol Mixture mL Graduated Cylinder 13 Quick Connect Coupling SSM0019 G RST Instruments Ltd. Page 12

13 Refer to Figure 4-3 for flushing tool accessory components. FIGURE 4-3 D AERATOR SS6000 ACCESSORY ITEMS 1 Make-Up Reservoir 2 ¼ Plastic Hydraulic Jumper Lines (2) 3 In-Line Filter Connected to ¼ Plastic Hydraulic Jumper Lines 4 Battery Charger for D Aerator with Plug Connector 5 Power Supply Cord for Battery Charger 6 Quick Connect Coupling 7 500mL Graduated Cylinder Refer to Table 4-2 for settlement cell accessory descriptions. TABLE 4-2 SETTLEMENT CELL ACCESSORY DESCRIPTION Component Function Description Inlet Quick-Connect In-Line Filter (External) Make-Up Reservoir Provides 100% filtering of the fluid returning from the settlement system hydraulic lines. Used during settlement system flushing to vent any excess system pressure and to ensure that the settlement It is recommended that the Hydraulic Jumper Line with the In-Line Filter be installed at the In-Line and used whenever the flushing tool is in operation. This will remove any dirt and/or debris present in the settlement system water and glycol mixture before entering the D Aerator flushing tool. The make-up reservoir will require monitoring during the flushing procedure and may need to be refilled between ½ and ¾ full with new water and glycol mixture, as SSM0019 G RST Instruments Ltd. Page 13

14 V AC to 12V DC Charging System cell pressure transducer will be kept at the lowest possible system pressure during flushing operation. 7.2 Amp-hr 12V DC storage battery may be recharged using the external V AC (50-60Hz) to 12V DC charging system. required. The fully charged 12V DC battery is capable of powering the flushing tool for 4 hours of continuous pumping. Recharging from near empty requires approximately 3 hours. Plug the flushing tool into the charger via the charging system should the tool be in operation in excess of 4 hours. 5 PREPARATION There are several preparations which are required in the shop before deployment to the field. These preparations will depend on which type of operation is being planned. 5.1 GENERAL PREPARATION It is recommended to perform the following list prior to using the flushing tool: 1 Check the in-line filter element for debris which may prevent the system from working properly. Clean the in-line filter with distilled water. 2 Function check the flushing tool to ensure all systems are operational and functioning. 3 Charge the on-board 12V DC battery for a minimum of 3 hours. 4 Include the external battery charger and any other extension cords required to reach V AC line outlets at the site. 5 Include an inverter should the only power source for field recharging be 12V DC from a nearby vehicle. 6 Include a tool box with an array of appropriate tools, spare lengths of ¼ plastic tubing, quick-connect coupling hardware, and other coupling connections. 7 Include sufficient volume of the 50/50 water and glycol mix for make-up volume or full system volume replacement, as required. 5.2 WATER AND GLYCOL MIXTURE A minimum of 4 litres of prepared 50/50 water and glycol mix should be taken to the field should it be required to top up or flush a system. The operator SSM0019 G RST Instruments Ltd. Page 14

15 should also prepare a container for any spoiled water and glycol mix. Glycol is a toxic substance and must be disposed of in an environmentally acceptable manner. 5.3 FEMALE QUICK-CONNECT The RST Liquid Settlement Systems and the D Aerator SS6000 Liquid Settlement System Flushing Tool were designed to have upward facing female Quick-Connects. Vertically oriented and upward facing female quick-connects must be filled with deaired 50/50 water and glycol mix from a laboratory squeeze bottle to eliminate the potential for air entry into the system prior to making a connection with a male quick-connect. Refer to Figure 5-1 to view correct female quick-connect coupling configuration. FIGURE 5-1 FEMALE QUICK-CONNECT COUPLINGS 5.4 JUMPER LINE PREPARATION 1 Ensure that the two jumper lines are completely filled with de-aired 50/50 water and glycol mixture. Connect the jumper lines to the outlet quick connect and pump the water and glycol mixture from the make-up reservoir using the flushing tool. Confirm that the inlet quick-connect is closed during this operation to ensure all of the water and glycol mixture will come from the make-up reservoir. 2 Facilitate the filling of the jumper lines by elevating and opening the male quick-connects at the far ends to allow the de-aired water and glycol mixture to enter the jumper line. The male quick-connects may be opened by either pressing the spring loaded shut-off valve or by temporarily installing a spare female quick-connect fitting at the end. SSM0019 G RST Instruments Ltd. Page 15

16 5.5 SITE PREPARATIONS FOR CIRCULATION OR FLUSHING OPERATIONS The following list of items must be addressed at the collar housing of each liquid settlement system prior to commencing a flushing operation. 1 Open the collar housing to gain access to the instruments. Identification the instrument tubing and carry out an inspection for any damage, irregular conditions, or evidence of leakage. 2 Check all the twin tube leads to establish their identity via their serial numbers. Re-mark any faded leads. Any new required identification labelling should be done prior to any line disconnections to avoid losing track of which hydraulic lead belongs to which instruments. 3 Disconnect any data loggers or automatic data acquisition systems to ensure the flushing operation will not trigger any alarm or cause unwanted record anomalies. 4 Check the fluid level in the Reservoir and tap the manifolds to observe if any gas bubbles are dislodged into the reservoir. Inspect the reservoir for debris or foreign materials. 5 Carefully measure and record the reservoir fluid level in relation to the level of the reservoir side vent tube. Any volume missing from the reservoir will represent potential leakage in the system and must be recorded for reference. 6 Individually flush the twin tubing pairs for each settlement cell. It is recommended that the shortest cell is flushed first to confirm the flushing equipment is in working condition. 7 Prepare a Field Data Record Sheet for field use. The sheet should include space for all pertinent information regarding the installed settlement cells to be flushed, including: Settlement Cell Designation; Sensor Manufacture; Sensor Type (RST Vibrating Wire); Sensor ID and/or Serial Number; Sensor Normal Maximum Pressure Range; Sensor Maximum Pressure Range; SSM0019 G RST Instruments Ltd. Page 16

17 This range is 2 times the normal maximum pressure range for a VW sensor. Current Settlement Cell Pressure; Maximum Allowable Sensor Pressure (equals 75% of the [sensor maximum pressure range minus the current settlement cell pressure]); Maximum Allowable Outlet Pumping Pressure at the Flushing Tool Outlet (equals 2 times the maximum allowable sensor pressure); Estimated Circulation Time for 120% return at the determined pumping rate for that settlement cell twin tubing installed; Flushing Data and Results; Any observations from the flushing procedure. Refer to Appendix C for an example field data record sheet. 5.6 DETERMINATION OF THE MAXIMUM FLUSHING OR CIRCULATING PRESSURE Some liquid settlement systems may be equipped with low range pressure transducers as low as psi or 70kPa which will be able to tolerate very low circulation pressures. The user must establish the range of the settlement cell transducer before attempting to do any flushing or circulation work to ensure that the transducer range will not be exceeded. The pressure applied to the outlet line drops to atmospheric pressure at the inlet line return to the flushing tool. In theory, the pressure being experienced at the settlement cell pressure transducer will be half of the applied outlet line pressure. This theoretical pressure is to be used when setting the maximum pumping pressure for circulation though the settlement cell. Damage to the pressure transducer may occur should the outlet line pressure under flowing conditions exceed twice the maximum rated pressure for the installed pressure transducer at the settlement cell. The pressure relief valve should be used to adjust and control the outlet pressure so as to not exceed the maximum pressure rating of the settlement cell transducers. Special steps need to be taken if the flushing work is to be carried out on a settlement system using strain gauge pressure transducers. Pressure ranges of strain gauge transducers need to be identified prior to the start of any flushing work to determine the maximum allowable outlet pressure. Strain gauge type transducers cannot be pressurized beyond the manufacturer stated maximum range. It is recommended that the maximum outlet pressure for strain gauge transducer settlement cells be set at less than 150% (2 x 75%) of the stated pressure range. In theory, this will provide a 25% safety factor at the transducer. SSM0019 G RST Instruments Ltd. Page 17

18 RST vibrating wire transducers can have their rated pressure range safely exceed by 100%. It is recommended that the maximum outlet pressure for vibrating wire transducer settlement cells be set at less than 300% (2 x 2 x 75%) of the state pressure range. In theory, this will provide a 25% safety factor at the transducer. Consult the manufacturer when determining the maximum pressure range for non-rst vibrating wire transducers. The twin tube plastic lines filled with the water and glycol mixture from the reservoir will also exert additional pressure on the settlement cell pressure transducer. This amount needs to be taken into account when determining the pressure transducer maximum exerted pressure. Refer to Appendix C for the Field Data Record Sheet which is used to document the settlement cells and calculate the maximum pressure that can be applied to each settlement cell. NOTE: IT IS HIGHLY RECOMMENDED THAT THE TRANSDUCER BE CONNECTED TO A DATA LOGGER OR READOUT UNIT DURING THE FLUSHING PROCEDURE TO ENSURE THE PRESSURE TRANSDUCER LOCATED AT A SETTLEMENT CELL IS NOT ACCIDENTALLY OVERPRESSURIZED AND DAMAGED. 6 OPERATION Two general operational modes are available for use with the flushing tool: Circulation Operation: The settlement system will be circulated in a closed loop utilizing an in-line filter installed at the inlet quick-connect and the makeup reservoir installed at the fill quick-connect to replace and to remove any air in the system. Flushing Operation: The settlement system will be circulated in an open loop with the old water and glycol mixture being wasted from an open line connected to the outlet quick-connect and new water and glycol fluid being added from the make-up reservoir installed on the fill quick-connect. The correct configuration of the equipment is required to be able to carry out either the circulation operation or the flushing operation. 6.1 RESERVOIR PURGE The fill quick-connect and attached make-up reservoir can be used to do a total flush and re-fill of the entire settlement system with new 50/50 de-aired water and glycol mix if required. A total flush and replacement operation may be required periodically if breakdown and/or contamination of the existing water/glycol mixture is noted. SSM0019 G RST Instruments Ltd. Page 18

19 The procedure is to pump new 50/50 de-aired mix into the settlement system from the make-up reservoir through one of the plastic twin tubes. The old mixture will be displaced from the settlement cell and system through the second plastic twin tube and then collected into a spoil bucket for disposal as the new 50/50 mix is pumped in. It is extremely important to ensure that the old fluid in the reservoir is completely replaced with new de-aired fluid. It is recommended that the reservoir be completely drained prior to the start of the flushing work and refilled with new de-aired 50/50 water/glycol mixture. The following procedure is recommended when purging the reservoir: 1 Detach all of the twin tube plastic lines from the manifold at the quickconnect fittings. The removed ends of the twin tube plastic lines will be the female ends and will need to be protected from dirt or debris. They may be hung out of the way or placed in a plastic bag. 2 Remove the reservoir and attached manifold from the mounting board in the instrument housing, usually attached by 4 bolts or screws into plywood. 3 Drain all of the water and glycol mixture from the reservoir and manifold into the waste container. Hold the reservoir and manifold in the inverted position while pressing open each of the male quick-fittings on the manifold body. This will allow air entry into the quick-connect fittings and the trapped water and glycol mixture to flow out through the manifold and reservoir. 4 Clean out the reservoir with a clean cloth and ensure no debris is left behind. 5 Re-mount the reservoir and attached manifold on the mounting board in the instrument housing. 6.2 RESERVOIR REFILL The following procedure is recommended when refilling the reservoir: 1 Connect the 0.5L make-up reservoir to the female quick-connect on the flushing tool. 2 Fill the make-up reservoir with approximately 0.5L of new 50/50 water and glycol mix. 3 Attach a length of ¼" plastic tubing at the outlet quick connect. Ensure the tubing will reach between the flushing tool and the reservoir and attached SSM0019 G RST Instruments Ltd. Page 19

20 manifold. The plastic tubing jumper will require a male quick-connect at the flushing tool end and a female quick-connect at the manifold end. 4 The ¼" plastic tubing jumper line must be purged with de-aired water and glycol mix before being refilled. This is accomplished by temporarily installing a male quick-connect into a female quick-connect at the far end of the jumper line and then circulating de-aired fluid while holding the line up in the air. When the return occurs, the temporary male quick-connect can be removed and the line will be full of de-aired water and glycol mix. 5 The jumper line is then installed on the manifold at the male quick-connect furthest from the reservoir. Eliminate the potential introduction of air bubbles into the system by using a laboratory squeeze bottle to place a small volume of the water and glycol mix inside an upward facing female quick-connect prior to connecting it with a downward facing male quickconnect. 6 The flushing tool is then used to fill the manifold and reservoir with new de-aired water and glycol mix. 7 Fill the reservoir to the vent tube level and reinstall the reservoir cover. Note the details of the purge and refill in the flushing records. 6.3 CIRCULATION AND FLUSHING PROCEDURES Prior to proceeding with a settlement cell circulation or flushing, the fluid volume of the system and pumping rate need to be determined so that the required pumping time can be set in the D Aerator tool. This is determined as follows: 1 The maximum pumping pressure for the settlement cell transducer is determined as explained in Section The D Aerator is then used to start the circulation and the output pressure is turned up to the maximum allowed pumping pressure as determined from the Field Data Record Sheet found in Appendix C. 3 The D Aerator is then turned off once the pressure is set and the flow is stable. The circulation system is altered to draw from the make-up reservoir and the return line is opened with a blank quick-connect fitting and placed into the top of a 500ml graduated cylinder. 4 The D Aerator is run using the make-up reservoir to supply the water and glycol mixture. The graduated cylinder is used to collect the output. The time to fill the 500ml cylinder is recorded and used to calculate the flow rate (millilitres per minute). SSM0019 G RST Instruments Ltd. Page 20

21 5 The ¼" twin tube plastic tubing used for liquid settlement systems has an I.D. of 4.76mm ( 3 /16"). The fill volume required per metre of the twin tube line (2 metres total length for supply and return) is approximately Litres x 2 = Litres. 6 This known twin tube volume and the measured flow rate is used to calculate the amount of time required to get a 100% flush of the hydraulic line. 7 An additional 20% volume needs to be circulated to ensure a 100% flush of the system. The settlement cell circulation or flushing procedure is ready to proceed when the following preparations are completed: The make-up reservoir is installed on the fill quick-connect and is ½ to ¾ full of fresh 50/50 water and glycol mixture. The two settlement cell twin tubes plastic lines are connected to the inlet quick-connect and the outlet quick-connect using the two jumper lines. The in-line filter has been installed on the flushing tool inlet line to filter all of the 50/50 water and glycol mixture re-entering the D Aerator Tool and the settlement system. NOTE: CIRCULATION PROCEDURES INVOLVE THE RE-USE OF THE EXISTING 50/50 WATER AND GLYCOL MIXTURE HELD WITHIN THE SETTLEMENT SYSTEM. THIS PROCEDURE UTILIZES AN EXTERNAL IN-LINE FILTER CONNECTED TO THE INLET QUICK-CONNECT, TO REMOVE ANY MINOR DIRT OR DEBRIS FROM THE CIRCULATED WATER/GLYCOL. THE D AERATOR TOOL WILL REMOVE ALL DISSOLVED GASES FROM THE SYSTEM. Flushing procedures involve the total replacement of all the existing 50/50 water/glycol mixture with new clean mixture. This involves the spoiling and disposal of the old water/glycol mixture. This procedure should be carried out when the water/ glycol mixture is known to be several years old and/or when the presence of dirt or debris has been noted. 1 Calculate the pumping time for full return circulation plus 20% using the required guidelines listed above. Note that the higher maximum pumping pressure, the faster the mixture will travel in the lines. Also noted that the cells with the longer hydraulic lines will develop higher friction line losses, which will slow the actual pumping rate. 2 Ensure that the Pressure Relief Valve is completely open (counter clockwise direction) so that over-pressurization cannot occur at start-up. SSM0019 G RST Instruments Ltd. Page 21

22 Adjustment of the Pressure Relief Valve to the maximum allowed level will require the use of a 5 /32" or 4mm hex key. 3 Turn the Power Switch ON. Adjust the timer controller to the required number of circulation minutes using the up/down arrow buttons and press SET to turn the pump on. The maximum is 60 minutes, so if more time is required, the D Aerator can be reset for the additional time. 4 Immediately adjust the pressure relief valve (clockwise direction) to provide the maximum allowable outlet pumping pressure for the settlement cell being circulated or flushed. NOTE: MONITOR AND ADJUST THE PRESSURE RELIEF VALVE AS NEEDED SHOULD THE BACK PRESSURE CHANGE. THE OUTLET PUMPING PRESSURE MUST BE CONTINUALLY MONITORED AND ADJUSTED AS REQUIRED TO AVOID ANY POTENTIAL DAMAGE TO THE SETTLEMENT CELL PRESSURE TRANSDUCER DUE TO OVER-PRESSURIZATION. 5 Remove the jumper lines once the flushing is complete. Reconnect the female ends of the hydraulic leads to the settlement system manifold. Eliminate the potential introduction of air bubbles into the system by using a laboratory squeeze bottle to place a small volume of the water and glycol mix inside an upward facing female quick-connect prior to connecting it with a downward facing male quick-connect. 6 Repeat steps 1 5 for the next settlement cell. 7 Compare pre- and post- pressure readings to see if there has been any affect from the circulation or flushing procedure. Maintain notes during the circulation or flushing procedure. 7 MAINTENANCE 7.1 STANDARD MAINTENANCE The relies on several key components in order to function properly. The tool will likely have to be returned to RST for testing, troubleshooting, and potential repairs should major operation problems occur. At the end of each daily use, it is highly recommended that the operator carry out a 1 litre clean water flush of the system using the two jumper lines to remove all of the water and glycol mix in the system and any debris or dirt. This system flush should be carried out with 1 litre of clean water. An open quick connect coupling will be required for the flushing operation. SSM0019 G RST Instruments Ltd. Page 22

23 Contact RST to discuss any function or performance issues. Field notes, recent flushing data, and photos will greatly assist any remote troubleshooting efforts prior to shipment of the flushing tool to RST for service if required. The in-line filter body can be opened for easy cleaning as required only when the flushing tool is powered off. Contact RST for replacement parts. There is a second in-line filter inside the D Aerator case. The internal inline filter should be checked for debris should any problems be experienced with the operation of the D Aerator. 7.2 INSPECTIONS OF LIQUID SETTLEMENT SYSTEMS Perform systematic site inspections of the installed instruments and surrounding area where the settlement cells and twin tube plastic lines are buried to confirm no unexpected disturbances or changes in elevation. Perform regular control surveys on the surface reference points to provide a back-up reference for the installed liquid settlement systems. 8 TROUBLESHOOTING 8.1 NO FLOW DURING FLUSHING No flow during a flushing procedure may be the result of a clogged filter element in the external in-line filter. Remove the filter by gently loosening the filter cavity nut and removing the strainer element. Clean the element by washing out any debris accumulated on the outside with clean water. Reinstall the strained element and cavity nut as seen in Figure 8-1. FIGURE 8-1 B-4TF4-LE INLINE FILTER & 40MICRON ELEMENT SSM0019 G RST Instruments Ltd. Page 23

24 8.2 AIR BUBBLES IN THE RESERVOIR MANIFOLD OR TWIN TUBE LINES Liquid settlement systems depend on the free and even distribution of hydraulic pressures throughout the entire connected system. The formation of gas bubbles within the reservoir manifold or the twin tube plastic lines will disrupt the hydraulic balance. Local changes to the specific gravity of the liquid within the settlement system will also cause offsets to occur. Surface tension occurring due to gas bubbles trapped in the tubing or manifold will act to restrict the free movement of water and glycol mixture within the system which will result in hydraulic imbalances. An annual flushing with de-aired 50/50 water and glycol mixture is highly recommended as preventative maintenance and to ensure the function of the system is stable and all gas has been removed. If unexplained changes or movements are noted within a system, it could be due to real changes in the relative elevations or it could be due to gas accumulation within the system. Flushing of the system should be carried out to provide an answer to these questions. 8.3 LEAKAGE IN THE TWIN TUBE LINES Leaks are relatively rare, but can occur. It is important to ensure that all connections are properly tightened during installation work, all installed materials are checked for flaws or damage, and no damage has occurred during the placement and backfill work. Above ground leaks in the manifold or collar connections are much easier to repair than buried leaks. A careful inspection should be carried out of all of the above ground tubing and connections to see if any problems are obvious. Any leaks found should be repaired immediately and the effected settlement cells flushed. Analyze the data to determine how much fluid is leaking on a daily basis. Refrain from topping the reservoir every few days. Let the liquid level track downward and provide an accurate record of the leakage rate. The system level data will be able to adjust to the slow leak rate should the daily leakage volume be concluded to be minute. Output data will be valid in relation to the reservoir level at the time of reading. The data analysis will involve more effort due to the requirement to correct for the slowing falling reservoir level but good data results should still be possible. Major fluid loss at a settlement cell may disrupt the ability to accurately monitor the other settlement cells. Determine which settlement cell is experiencing the leak and remove it from service. This will allow the SSM0019 G RST Instruments Ltd. Page 24

25 remaining cells in the liquid settlement system to return to stable and static operation. 8.4 BLOCKAGE IN THE TWIN TUBE LINES A blockage or pinch could occur in one or both of the twin tube lines to one of the settlement cells which would severely restrict flushing circulation. This occurrence could be due to poor installation procedures or materials or extreme settlement movements. Other settlement cells that pass through the same buried location may also be at risk of future blockages or pinching. The surface area should be inspected for evidence of ground movement. Excavation may be necessary to restore the twin tubing to service although it may risk damaging other settlement cells installed in the same trench. It is advisable instead to install a new settlement cell at an offset distance. 9 SERVICE AND REPAIR Contact RST for product service or repair not covered in this manual. Refer to the inside title page of this manual for RST s contact information. SSM0019 G RST Instruments Ltd. Page 25

26 Appendix A VARIOUS COMPONENTS OF LIQUID SETTLEMENT SYSTEMS FIGURE A-1 VARIOUS COMPONENTS OF LIQUID SETTLEMENT SYSTEMS SSM0019 G RST Instruments Ltd. Page A 1

27 Appendix B TIMER CONTROLLER The D Aerator Flushing Tool is controlled by a digital timer which may be programmed to any desired run time up to 60 minutes. The user may set and activate the digital timer by using the face keys as follows: 1 Press SET and 0 will appear on the display. 2 Use the up/down arrow buttons to increase or decrease the required pump run minutes. The timer cannot exceed the pre-programmed time parameter which is 60 minutes. If more time is required, the timer can be reset for the additional time once the 60 minutes has run out. 3 Press the SET button to confirm the number of minutes and start the timer. This will close the relay output and start the machine. 4 Deactivate the timer by holding the SET button down for 1 second. 5 Listen for an internal buzzer that will beep twice when the timer interval has expired. 6 Turn the main power switch to OFF to turn the pump off any time before the timer has finished counting down. Any problems experienced with the digital timer operation can be reset and reprogrammed as follows: 1 Turn the D Aerator unit ON at the main switch. 2 After the normal wake-up sequence, the timer control screen should read OFF. 3 To enter the programming mode, press the SET button and hold down for 8 seconds until Ut appears on the screen. Ut is for programming in Units of Time. 4 If Ut is not seen on the screen, hit one of the Arrow buttons to cycle through the 4 options until Ut is found and displayed. 5 Press the SET button once to select the time unit. 6 Use the Arrow buttons to select min for minutes. SEC is for seconds. SSM0019 G RST Instruments Ltd. Page B 1

28 7 Press SET which will return the timer controller to the Ut screen. 8 The timer controller is now re-programmed. 9 Press the SET and down Arrow buttons at the same time to exit the programming mode. 10 The D Aerator unit will remain on. SSM0019 G RST Instruments Ltd. Page B 2

29 Appendix C FIELD DATA RECORD SHEET EXAMPLE FIGURE C-1 DATA RECORD SHEET EXAMPLE SSM0019 G RST Instruments Ltd. Page C 3