LORD Corporation Downhole Test Simulator Feasbility Study

Matthew Biron1, Daniel Bowers1, Nicholas Fewell1, Hyungsuk Kang1, Abigail Tremont1, Jason Whyte1, Sam Zimmerman1

1Rochester Institute of Technology

Proper testing of vibration isolators and shock dampers used in the downhole drillling industry before the product is placed into production is scarse. Creation of an in-house testing facility for downhole drilling vibration isolators that would resemble the environment downhole would give any company a competitive advantage in the field. This project focuses on the research, analyses, simulations, and small-scale prototypes that were completed to determine the feasibility of a testing facility for downhole vibration isolators and shock dampers. To achieve the project deliverables a complete feasibility study was completed along with 3D models of the system. The results of the designed tests concluded that the creation of a in-house testing facility could be feasible with several considerations for improvements.

I. BACKGROUND

In the Oil and Gas industry, it is vital to ensure that the tooling used downhole can withstand the environment deep beneath the Earth. The Axial Isolators that LORD Corporation designs and manufactures are crucial to protecting downhole tooling from axial and lateral shock and vibration. Currently, LORD has no standard practice to test their vibration isolators before they enter the field. Data collection and failure modes are determined after their product has been used in real-time production.

The intention of this project is to determine if LORD has the capabilities to create an in-house testing facility for their vibration isolators. Particularly, in determining the feasibility of this facility the focus on the design will be on the pressure vessel in which the testing will occur along with the axial and lateral shock and vibration application, and mud flow process throughout the vessel. By doing this, LORD will have an advantage in the Oil and Gas Industry by providing their customers with a better guarantee that their part will survive in its environment.

Specifically, the approach taken to prove the feasibility of the test simulator was to conduct several mathematical analyses, simulations, and small-scale prototype tests. These tests were designed and completed to prove that each subsystem can function as a part of the entire system. The physical prototypes were scaled down to ensure that they could be properly tested.

Along with technically validating each subsystem, research was conducted to determine a bill of materials for the testing vessel. From this research, a thorough cost analysis was created. Future risks and recommendations were considered as well.

II. SYSTEM OVERVIEW

For design purposes, this complex system was broken into four subsections which include the mud flow, axial and lateral forces, the torsional force, and the structural systems. Since these have been designed separately they can each function

independently from each other as well as be combined to fulfil the specified requirements. Each subsystem is tied together using a centralized control system.

A. Overall System OverviewThe system imparts static and dynamic forces to a test

article located inside a pressure vessel. Through the pressure vessel flows drilling mud at pressures up to 20ksi and temperatures up to 350ºF. The forces can be applied in the torsional, lateral, and axial direction or in any combination of these. A cutaway of the pressure vessel design is shown below, in Figure 1.

FIGURE 1. PRESSURE VESSEL DESIGN

An overall system design can be seen below in Figure 2. In general, these processes are controlled through feedback loops to ensure appropriate forces and conditions are being generated. Furthermore, it is designed such that any non-linear forces are translated to the pressure vessel before they arrive at the axial/lateral seals. In the same way the torsional side is braced against axial and lateral motion so as to minimize the undesirable forces seen at the rotary seal. It should also be noted that, as designed, the system is sufficient to flow mud around and through a test article.

FIGURE 2. OVERALL SYSTEM DESIGN

While designing the pressure vessel and overall system, the team had several engineering and customer requirements to consider. These considerations are outlined below in Table 1.

TABLE 1. SYSTEM CAPABILITES

Engineering Requirement CR Value

Adjustable Temperature (F) 0-350

Adjustable Pressure (ksi) 0-20

Mud Flow Rate (GPM) 350-800

Mud Temperature (F) 125-250

Static Axial Load (lbf) 4-1000

Static Lateral Load (lbf) 4-1000

Static Torsional Load (kip-ft) 0-50

Dynamic Vibration Load (g) 0-50

Vibration Frequency (Hz) 1-350

Dynamic Shock (g) 200-1000

Dynamic Shock Duration (ms) .5-20

B. Axial-Lateral Force Subsystem 1) Axial-Lateral Force ApplicationThe axial and lateral dynamic forces are being applied to

our system via two 55,000 pound shakers. These shakers were quoted from the Unholtz Dickie Corporation (UDC), and can apply up to 55,000 pounds in both shock and sinusoidal vibration, along with the capability to handle high static-load situations. Much of the setup, mounting, and power usage design are handled by UDC, and they have offered to help design system mounts for this application. Each shaker has a footprint of 13’8”x7’7” and weighs 50,000 pounds.

Mounted to each of the shakers will be a Moog ball-screw actuator. These ball screw actuators will handle the static forces as well as any ultra-low frequency vibrations specified (vibrations on the order of 1 Hz or lower). It was confirmed by Moog that these actuators can handle the vibration loads transmitted through them, which is the primary reason these actuators were chosen over a hydraulic actuator. Each actuator has a continuous stall force of 1,971 pounds (peak stall force of 4,985 pounds) and a maximum shaft speed of 8.1 inches per

second. These actuators will be mounted to the slip tables of the UDC shakers using mounts designed by UDC.

2) Axial-Lateral Transfer LinkageIn order to meet Engineering Requirement which requires

both a static axial and lateral load, we designed a system to transfer two axial forces into an axial force and a lateral force. This was done to prevent excessive shear forces on the pressure vessel that would have resulted from directly applying a lateral force to the system. The linkage is designed with a 3:4 axial/lateral force ratio, so that the amplitude of the lateral displacement is amplified. This also means that the force applied is attenuated by the same ratio, which must be taken into account. Based on a pair of input forces F1 and F2, the forces transmitted through our designed linkage are as follows:

FA = F1 + F2

(a )

FL = 34 ( F1 - F2 )(b )

where A is the force applied in the axial direction and L is the force applied in the lateral direction. Using these two equations, it is possible to generate any axial and lateral force through a well-designed combination of input forces.

C. Torsional Force SubsystemThe torsional subsystem exists to fulfil the requirement of

applying dynamic torsional load at up to 50g and a static torsional load of up to 50 kip-ft. In addition, the torsional side must be robust to the linear and axial forces which are transmitted through the test article. The design of the torsional system must also take into account the damping created by the mud flow.

1) Torsional Force Transfer PieceThe torsional transfer piece is used to reduce the number of

holes and subsequent seals needed for the design. The transfer piece is a steel rod which is attached to a casted junction piece. The transfer rod simply allows for the application of the static and dynamic forces external to the pressure vessel and inner pipe. This transfer piece is 6” in diameter is made from ASTM A108 low carbon steel.

2) Torsional Force ApplicationThe torsional force is applied by two MOOG electric linear

actuators with a stroke length of 12in. These two actuators are attached to a CAM transfer piece which is permanently fixed to a steel transfer piece. The test article is to be threaded into a casted junction piece which is threaded onto the transfer bar. The junction is designed to allow mud flow passing through the test article to exit and flow out of the tank. The linear actuators in this design have been specified by MOOG to be able to handle the dynamic loads passing through the system.

3) Dynamic Load ApplicationThe dynamic load is applied by high force shaker supplied

by Unholtz Dickie Corporation which is capable of generating 55,000lbs of vibration. The dynamic load is applied independent from the static load through the use of a high

force hydraulic clamp supplied by Planet Products. This clamp is located outside of the pressure vessel and thus, in a region where the axial and lateral vibrations are negligible. Thus, the only vibration is orthogonal to the hydraulic clamping force and will not propagate through the hydraulic system. The control of this system is such that the static force is realized before the clamp is closed. In this manner any deflection caused by the torsional static force will not distort the application of the dynamic load. This design is further analyzed in following sections.

4) Torsional Force ConsiderationsFirstly, the torsional system must be robust to the axial and

lateral loads being transmitted through the test article. To accomplish this the transfer piece is braced internally to the wall of the pressure vessel. This will prevent any axial distortion from being transmitted to the seals or to the CAM system. Next, the transfer piece is externally braced at the end against lateral forces. This will prevent any lateral motion from wearing on the rotary bearings or from bending the actuators.

5) Torsional Control SchemeThe torsional system uses a feedback system to achieve the

forces specified. There are accelerometers to measure the input dynamic forces. The tri-axial data is fed back to the controller supplied with the high force shaker. In this way the shaker can increase inputs to meet the specified conditions. The static forces work in a very similar manner using a load cell. In the case of the static forces the data from the load cell is fed back to the MOOG controller. There is an overall control system which keeps the correct order of operation. First, the static force must be realized so any distortion of the UUT will occur. After this the hydraulic clamp is closed and the dynamic force can be applied. At the end of the test this must be repeated in the opposite order to ensure no stresses are transferred to the dynamic system. For safety all forces are monitored to ensure the magnitude does not change by more than 15%. If any force changes by more than 15% it is assumed that a failure has occurred somewhere in the system and it automatically goes into emergency shutoff.

D. Mud Flow Subsystem1) Mud Flow ApplicationThe mud flow system is a closed flow loop design utilizing

diesel powered hydraulic fracking pumps as the power source to move the flow. The mud begins in a 2100-gallon storage tank where it is heated to the desired operating temperature, as specified in the engineering requirements, using a Chromalox Large Tank Immersion Heater. Whilst in the tank the mud is kept in motion using a GN Solid Controls Agitator to prevent clumping or settling. A boost pump is used to pressurize and move fluid such that the main pumping system can draw fluid. The main pumping system includes 7 total fracking pumps, with 6 pumps being in use and one pump used for backup. Each pump is capable of meeting the 20,000 psi pressure requirement as stated in the engineering requirements. The 6-pump configuration will allow for the volumetric flow rate requirement of 350-800 GPM to be met as well. Each pump in the system will have its own cooling tower to maintain proper

performance. At the maximum operating condition the pumping system will be utilizing 12,500 BHP and 714 gal/hr of diesel fuel. The overall footprint for the pumping system is 70’ x 60’.

The pumping system would be purchased as a complete package from National Oilwell Varco’s Pressure Pumping Equipment group.

2) Mud Purging ProcessAfter running tests it will be imperative that the flow loop

is flushed clean of any residual mud. This residual mud if not cleared from the system could eventually cause problems with clogging flow paths as well as unwanted debris in crucial test areas. To combat this problem a mud “purging” process was developed. This process adds an additional storage tank for water that is integrated into the main pumping system by way of two switching valves, for outlet and return flow lines. This clean water will then be pumped through the system to cleanse it of any remaining mud. The water tank will then have to be periodically emptied and cleaned in order to maintain the water cleanliness.

3) Mud Flow Control System In order to control the mud requirements, pressure sensors,

heat sensors, and flow sensors were required to be included in the design. The heating has the simplest form of control. The design uses at minimum two thermocouples to measure the heat of the mud. More may be needed in the tank to ensure that the heat is even while the mud is inside of the tank. The specific thermocouple utilized is called RT02 from pyromation. It has a sheath to protect from external wear such as mud. The sensor is able to withstand up to 200°C. One thermocouple would be located right before the pipes enter the pressure vessel and the rest would be located in the tank. If the pipe thermocouple temperature was too low then the tank can be heated up further to increase the output temperature. The tank thermocouples would then be there to ensure that the tanks temperature don’t reach unwanted values and that the heat is distributed evenly throughout the mud.

The flow and pressure control of the mud is slightly more complicated due to their dependency on each other. Both sensors are located next to each other right before the pipes enter the pressure vessel. The pressure sensor is a Hammer Union Pressure Sensor 434 which is already used in the oil and gas industry and supports up to 20k psi. The flow sensor is Turbine Flow Meter – FT Series from Flow Technology. The sensor is able support the pressure, flow, and temperature of the mud. A more specific control scheme will need to be devised for precise control. The basis would be that the pressure sensor helps determine how much power is supplied to each mud motor and the flow sensor helps determine how many motors should be on. Because of the dependency between the pressure and flow rate with the more, the control scheme may be more complicated for correct outputs. This control scheme was not specified as it was beyond the scope of this project and of what would be useful in proving the feasibility of the design.

E. Pressure Vessel Subsystem1) Pressure Vessel Overview

In order to contain the 20,000-psi pressure acting on the unit under test, we designed a pressure vessel capable of containing this load. The cylindrical pressure vessel will have a 28-inch inner diameter and be 12 feet long internally. In order to withstand the pressure, the entire pressure vessel needs to be made from 8-inch thick alloy steel. Each end will consist of a gasketed hatch in order to access the interior of the container. These gaskets will have holes for the load application shafts (2 on one side, 1 on the other side) with the appropriate bearings and seals. Each end will also have a drip collector, which have been designed to collect any mud that leaks through the seals during operation. These collectors will need to be routinely checked and emptied, and can be used as early indicators of seal failure (assuming the failure is not catastrophic).

Inside the pressure vessel, there is an inner sacrificial low carbon steel pipe designed to prevent wear and tear on the external pressure vessel. The interior pipe is 18 inches in diameter on the axial/lateral load side, and steps down to 10 inches in diameter before reaching the unit under test. The ten inch section is completely removeable and is made to be cycled often due to wear and tear.

The pressure vessel has five permanent holes: two mud inlets, the mud outlet, the heated air inlet, and the pressurized air inlet/outlet. The mud inlets enter the pressure vessel at a 30 degree angle to improve flow and prevent excess turbulence within the system. They pass through the outer wall of the pressure vessel and connect with the inner steel pipe. The mud outlet is perpendicular to the pressure vessel, and must be located at the lowest point in the system for drainage purposes. The mud outlet connects with the inner pipe and passes through the pressure vessel near the torsional side. The heated air inlet connects to the air circulator and heat exchanger, and passes through the pressure vessel to connect with the interior pipe near where the unit under test sits. This is to ensure that as much heat gets to the test article as possible before the air cools. This air is unpressurized and simply generates an initial temperature condition for the test. The air will leave the pressure vessel through the mud outlet, which vents into an open container which is capable of handling extra air. The pressurized air inlet/outlet is a valve that connects the air compressor to the pressure vessel. This valve allows air in and out, and is used to pressurize the system to 20,000 psi and to release the air before opening the pressure vessel.

The interior of the pressure vessel will have steel support structures to hold up the interior pipe. The interior pipe will also be bolted into place with gaskets on either end, ensuring that no mud leaks from the interior pipe into the main portion of the pressure vessel.

2) Pressure Vessel Control System In order to control the pressure correctly to create a zero

pressure gradient across the inner pipe the design uses information from the mud system and pressure sensors within the pressure vessel itself. The pressure vessel sensors are Series GT16XX Industrial Pressure Transducers and Pressure Transmitters which are supplied by LORD. The sensors will be able to withstand up to 40k PSI. The control scheme itself would be rather simple. Based on the mud system pressure

information, the air pump will be brought up to that pressure and the GT16xx will be used for direct feedback of the pressure seen. The current design has at minimum two of sensors on both sides of the vessel but more can be added to ensure uniform pressurization. HVAC Subsystem

3) HVAC System Overview The Heating, Ventilation, and Air Conditioning (HVAC)

system was designed solely to support the first engineering requirement. The temperature required for the system had to range from 0°F to 350°F. To simplify this the temperature ranges were separated to be from 0°F to 70°F and 70°F to 350°F where 70°F is the standard room temperature. This was done in order to incorporate current heating and cooling units easier into the design. The HVAC is then split into two different sections in order to achieve the requirement. The heating unit was benchmarked and the one chosen for the design was the CAB-611 from Chromolox. The CAB-611 supports up to 440°F and includes a blower and duct to create air currents. The heater is then connected to a valve through simple ducting. The valve is a hydraulic controlled drilling type choke valve from Cameron. The valve is connected to the pressure vessel and has a channel directly to the testing tube in order to reach the part. The drilling choke is necessary because once the test runs there will be marginal pressure on one side and the pressurized mud on the other so a more complex valve is needed in order to contain the pressures correctly. With this connection, the air around the unit under test can then be heated up to necessary conditions.

The cooling was unit was researched and, in order to cool a larger amount of air, a custom model was needed. A custom cooler was quoted by Xchanger Inc. The custom cooler uses liquid nitrogen and includes a blower. The custom unit is specified to reach the required 0°F from normal room temperatures. The cooler is connected similarly to the heating system through its own choke valve. With this, there is then a path of the cooler to the unit under test.

The control unit is fairly simple due to the focus being on heating or cooling the unit to a set point. Once that point is reached the test will run and the requirement will be fulfilled. The connections leading to the valve will have a temperature sensor and there will be a temperature sensor inside the testing tube on the torsional side. Because the unit under test will be similar to the metal attachments for the torsional end, the temperature of the unit under test would be approximately the same. Direct tests could be done in order to better approximate a model for the temperature control based on the sensors feedback. This specific design with the temperature sensor was done in order to avoid problems with a varying unit under test and from the mud flow affecting the sensors or wires. This concludes how the HVAC system is set up for the design.

III. SYSTEM VALIDATION

In order to prove the validity of the designed system to the engineering requirements, several different kinds of tests were run. These tests are broken down into three different categories. Analysis tests were based on hand calculated formulas and values. Simulation tests were done for better approximations to the real world. Prototype tests were completed as small scale

tests of major components. The tests also reflect how much risk there was in each section. For example the heating was straightforward so only analysis tests were done but the axial and lateral had all three forms of tests done in order to prove its design throughout the project.

Formal test plans were created to test each of the engineering requirements. All results from the test plans were then examined by a subject matter expert to verify the outcomes. Once the subject matter expert is okay with the process and results, the final report for the test could then be written up. The report for the tests include the specific actions that were taken, the raw data of the results, who the subject matter expert was that reviewed the test, and a final summary of how the results pertain to the requirements. With this setup, the tests were then completed. Below, Table 2 shows how each engineering and customer requirement was validated.

TABLE 2. VALIDATION TYPES

Engineering Requirement CR Value Test Type

Adjustable Temperature (F) 0-350 Analysis

Adjustable Pressure (ksi) 0-20 Analysis, Simulation

Mud Flow Rate (GPM) 350-800 Analysis, Simulation

Mud Temperature (F) 125-250 Analysis, Simulation

Static Axial Load (lbf) 4-1000 Analysis, Simulation, Prototype

Static Lateral Load (lbf) 4-1000 Analysis, Simulation, Prototype

Static Torsional Load (kip-ft) 0-50 Analysis, Simulation, Prototype

Dynamic Vibration Load (g) 0-50 Analysis, Simulation, Prototype

Vibration Frequency (Hz) 1-350 Analysis, Simulation, Prototype

Dynamic Shock (g) 200-1000 Analysis, Simulation, Prototype

Dynamic Shock Duration (ms) .5-20 Analysis, Simulation, Prototype

There were two major prototype tests that were designed and conducted to prove the feasibility of the axial and lateral forces and the torsional forces. They are described below:

A. Axial-Lateral Linkage Small Scale PrototypeIn order to test the effects of water on our vibration

transfer system, we designed and ran a small scale prototype test of the proposed linkage. The prototype system maintained the same aspect ratio as the proposed final design, and had significantly reduced loads to prevent mechanical failure during the test. The goals of the prototype were to determine if our system was capable of generating axial motion and lateral motion independently and to determine the damping effect of the water on the system as a whole. We were able to produce pure axial motion, and we were able to produce significant lateral motion with only a small amount of axial vibration. This is likely due to the geometry of the system and may not be avoidable. Through the test we discovered that the water had a different damping effect on each direction of motion

depending on which direction had the larger cross-sectional area. Since the lateral direction was more aerodynamic, it had a significantly lower damping factor than the axial direction. This will change significantly in the final product, so additional tests will need to be run on the full test rig to determine the effects of the mud on the vibration. The following prototype setup is shown below in Figure 3.

FIGURE 3. AXIAL-LATERAL PROTOTYPE SETUP

B. Torsional Load and Vibration Scaled PrototypeIn order to test transmission of vibration and load, we

designed and ran a small scale prototype test of the torsional load and vibration. The prototype system maintained the same aspect ratio as the proposed final design, and had significantly reduced loads to prevent mechanical failure and reduce the cost of required equipment and structure. The goal of the prototype were to determine if our system was capable of generating torsional load and vibration independently to the unit under test. We were able to produce torsional load from an air spring, and we were able to produce torsional vibration from an electromagnetic shaker. Through the test we determined that the natural frequency of the system was consistent with various torsional load and vibration conditions, which means the stiffness of the system was consistent during the test. The prototype setup is shown below in Figures 4 and 5.

. FIGURE 4. TORSIONAL PROTOTYPE SETUP

FIGURE 5. TORSIONAL PROTOTYPE SETUP

IV. RESULTS

At the conclusion of the analyses, simulations and prototypes it was determined that a majority of the engineering and customer requirements could be met. The following table shows what values that the team was able to determine that the system could meet.

TABLE 2. ACTUAL VALUES

Engineering Requirement CR Value Actual Value

Adjustable Temperature (F) 0-350 0-275

Adjustable Pressure (ksi) 0-20 0-22

Mud Flow Rate (GPM) 350-800 350-800

Mud Temperature (F) 125-250 90-275

Static Axial Load (lbf) 4-1000 4-1000

Static Lateral Load (lbf) 4-1000 4-1250

Static Torsional Load (kip-ft) 0-50 0-60

Dynamic Vibration Load (g) 0-50 0-70

Vibration Frequency (Hz) 1-350 25-300

Dynamic Shock (g) 200-1000 0-140

Dynamic Shock Duration (ms) .5-20 .1-80

Along with validating the engineering and customer requirements for the feasibility study, the team created final 3D models of the pressure vessel and the overall system which were turned over to the customer, LORD.

V. COST ANALYSIS

A. Cost OverviewA bill of materials (BOM) containing the pieces of the

simulator which were deemed to be most expensive can be found on EDGE under the “Full System BOM” link in the work breakdown structure. These components come to a total of $6,000,000 which is estimated through both quotes and rough order of magnitude (ROM) requests made to viable

manufacturers. Also included in this report is an estimate of operational costs purely for the running of the test simulator. It should be noted that no amounts provided here include building costs, or the cost associated with housing this test apparatus.

B. BOM ReviewThe BOM is broken into four sections including the mud,

loads and vibration, structural, and controls subsystems. For the mud subsystem the largest contributor to the cost are the mud pumps. Here it may be possible to incrementally purchase the expensive pumps. Before taking this approach one must thoroughly study the relationship between the number of pumps present and the pressure and flow attainable. Also, included in the mud section are the holding tanks for the mud and flush water as well as the immersion heater necessary to bring the mud up to temperature.

Subsystem Total CostLoads/Vibrations 3,097,799.70Mud 9,180,575.00Structural 2,224,209.02Controls 35,950.08Acquisition Cost 1,453,853.38Total 15,992,387.18

Under the loads and vibrations category the largest contributors are the shakers necessary to reach the acceleration requirement while the system is under the maximum static load. Following this, the next largest cost at $40,000 a piece are the linear actuators needed to create the lateral and axial loads. These actuators were directly quoted from MOOG with the understanding that they would probably be customized when actually purchased. There aren’t any components here that present a large risk of hidden cost increases.

The most difficult category to handle is the structural category. With this system design the largest number of custom components fall into this category. The pressure vessel is the most important piece as far as safety is concerned and it is also the part that requires the most customization. With a ROM price of $1,300,000 the pressure vessel represents a large risk of cost volatility as it is difficult to predict the cost of customization. The next largest cost contributor is the inner pipe. This is the combination of the “inner pipe” and “inner pipe junction.” Again this piece will require a one off custom casting to produce the junction piece. At $600,000 the inner pipe is the piece that is meant to take the brunt of the wear and will need to be replaced. It may be desirable to acquire multiple diameter inner pipes and junction pieces in order to test multiple parts. Only the cost of purchasing a single inner pipe and junction piece is considered in the BOM. Included in the BOM is an estimate for the cost of pipe necessary to get the mud from the pumps to the pressure vessel. Clearly this is very dependent on the layout of the facility and how close the pumps can be located with respect to the pressure vessel. With this in mind the rough layout we came up with used less than the 500ft quoted in the BOM. Another noticeable cost comes from the air compressor used to achieve the 20ksi air pressure. This should not present much risk for increase as it was a quote from Hydropac. It is important to point out that the cost of a lubrication system for the seals is not included in the BOM and

will be critical to the life and proper operation of the seals. The final part that may be difficult to source are the bearings required to prevent force from being transferred to the seals. Included in the BOM is a ROM cost for these, but it is likely that these will be custom bearings due to the size and force they will experience. The last thing not included in this BOM is any structural supports for the pressure vessel itself. Since all forces generated are transferred to the pressure vessel before getting to the seals it may be necessary to brace the pressure vessel to transfer forces to an external support system. With all of this in mind the structural category poses the most risk for budget increases.

The final category contains the costs for controls. This cost is closely tied to the cost of controlling the MOOG actuators and the shakers. All of the sensors are on the order of $1,000 and were specifically designed to be robust to vibration and the abrasive mud. None of the sensors require customization which makes them simple to acquire and replace. There are no surprises in this category and very little risk for cost increases.

The cost of housing the testing rig along with the infrastructure for supplying electricity to the system are not estimated in this study. It should be expected that the infrastructure necessary to support the entire system will be extensive. This stems partially from the space necessary for the mud and water tanks along with the large space taken by the pumps. For the electricity it is probable that the system will require infrastructure on the order of dedicated transformers and should not require anything as extreme as a dedicated substation.

C. Operational Cost Review Two estimates are provided for operational cost which

includes running the simulator for half of the year and an estimate for running the simulator for half the business hours in a year. The cost associated with operators was estimated based on the need for 4 operators for setting up the system and 1 operator while the system is running. Furthermore, it was estimated that setting up the system would take 20% of the time and it would run with a single operator for the remainder. It can be seen that the estimated cost per hour of an operator is $100. The largest contributor to operational cost is the price of diesel for the pumps. This estimation is based on running at full capacity the entire which would require the use of 6 pumps. These 6 pumps would go through 714 gallons per hour which at the current diesel wholesale price would end up costing around $1,100 per hour. Both the cost of water and electricity are relatively cheap when compared to the other operational costs and will only change incrementally depending on usage.

It is prudent now to address the cost associated with the maintenance of the simulator. At this point in time it would be an ambitious task to attempt the estimation of the lifetime with regard to almost all components. It can be said that the parts most probable to need frequent replacing are the seals. Each time the seals are replaced it will cost $7,135 in parts alone. It is also foreseeable that the pipes will need biannual cleaning which is in addition to the flushing which is to be performed

after every test. The pumps will need maintenance on par with usual diesel engine care which is specified by the manufacturer and is dependent on the exact model purchased. It is known that the design sacrifices the inner pipe to preserve the more costly pressure vessel. It is unknown how fast this inner pipe will deteriorate.

D. Budget AlterationsIt is possible to make incremental alterations to the design

and reduce the overall cost. In doing this, one must first attain an end goal and keep this in focus. For example, the pressure requirement drives a major portion of the cost in both the structural and mud subsystems. One might correctly observe that reducing this requirement in the short term would reduce the cost associated with the pumps and the cost associated with the pressure vessel. The pumps could then be scaled up over time making the cost incremental and built into the budget over several years. This is not the case with the pressure vessel though. Every time the pressure capability is increased the pressure vessel would have to be entirely rebuilt. In this way, the end goal must be the beginning of any discussion on cost reduction. With this being said, the two largest contributors to the overall cost are the pressure and dynamic load requirements. To this point it may be possible to decouple the static and dynamic loads which may results in a size reduction for the shakers. It is also safe to say that the flow and pressure requirements are driving the operational cost through the consumption of diesel. In conclusion, there are extensive possibilities for system redesign driven by the desire for cost reduction.

VI. POTENTIAL RISKS

Several risks were identified throughout the system design and validation processes. By conducting the analyses, simulations, and prototype tests possible risks were mitigated based on the results from each test. The following section will describe in detail the risks that were still prominent even after thorough testing and research.

A. Sealing Risks Major risks with the system design pertain to the sealing

that will be used in the pressure vessel design. It is possible that the sealing will break down to due actuation, fatigue, abrasion, or excess applied loads. These risks were unable to be mitigated through proper validation testing since the proper resources were not available to team. Also, the team’s budget does not allow for testing of the seals at an off-site testing facility. It is the team’s suggestion for LORD to follow through with the testing of the sealing options at an off-site testing facility.

B. Subsystem Integration Risks The team designed all of the analyses, simulations, and

prototypes with the intention for each subsystem to properly function with each other. Although proper testing was conducted, the team did not have the opportunity to run an overall small scaled test of the entire system. It is still a

potential risk that the subsystems will not properly function with each other but it is not likely.

C. Heating Stress RisksThermal shock on the seals has the potential for premature

failure. This should be properly tested before creating a final design.

VII. FUTURE RECOMMENDATIONS This project is not finalized by any means, and we recommend these follow-up projects before the system is built and finished:

1. Validation and Life Span Testing for Seals – The seals have been quoted to be potentially feasible, but they should definitely be fully tested before installation.

2. Torsional Load Simulation – This simulation was not reasonable for undergraduate students, but it may be feasible to hire a team of graduate students to run this simulation.

3. System Maintenance Testing – Testing should be done on individual parts to determine a full maintenance plan.

4. Reduced Cost Design – Our design is specified to meet as many of the original engineering requirements as possible. It may be possible to significantly reduce cost by relaxing some of the engineering requirements.

5. Improved Functionality Design – Lord initially requested multiple pieces of functionality that did not make the final design, including hypotrochoidal vibration, rotating the entire system to simulate vertical and horizontal drilling, and a mud motor. Now that there is a base design to work off of, it may be reasonable to modify our design to achieve these new functionality.

6. In-Depth Projects – Each individual subsystem is reasonable to be an whole project on its own. Each project should be tasked with fully testing the system, improving and optimizing the design, and validating all of the individual components.

7. Building Design – In the original PRP we were tasked with designing the facility to house this system. Since RIT does not currently have a civil engineering program, this was not feasible for our group. A full project to design the building for this will be necessary before final build.

VIII. CONCULSIONS After final consideration, it was determined that the creation

of a testing facility was indeed feasible. Through the use of thorough research, analyses, simulations, and prototypes the designs for the facility were determined. Several recommendations were made regarding risks for the implementation of the designs as well as future projects.