Copyright 2005, Offshore Technology Conference This paper was prepared for presentation at the 2005 Offshore Technology Conference held in Houston, TX, U.S.A., 25 May 2005. This paper was selected for presentation by an OTC Program Committee following review of information contained in a proposal submitted by the author(s). Contents of the paper, as presented, have not been reviewed by the Offshore Technology Conference and are subject to correction by the author(s). The material, as presented, does not necessarily reflect any position of the Offshore Technology Conference, its officers, or members. Papers presented at OTC are subject to publication review by Sponsor Society Committees of the Offshore Technology Conference. Electronic reproduction, distribution, or storage of any part of this paper for commercial purposes without the written consent of the Offshore Technology Conference is prohibited. Permission to reproduce in print is restricted to a proposal of not more than 300 words; illustrations may not be copied. The proposal must contain conspicuous acknowledgment of where and by whom the paper was presented. Write Librarian, OTC, P.O. Box 833836, Richardson, TX 75083-3836, U.S.A., fax 01-972-952-9435. Abstract Thunder Horses high pressure and temperature environment, added to equipment size and enclosed volume, made pressure testing potentially hazardous and failure consequences far-reaching. The industry does have a fairly good safety record; however, near misses are still prevalent. Though few and far between, when incidents happen, they tend to be spectacular. Evaluating ballistic potential of objects flying off the equipment demonstrated how exposed we would be, given a sudden catastrophic failure. This led to a major re-assessment both in mitigation methods and test facilities.

Introduction Pressure testing from a design engineers perspective is a validation of his or her analyses work. The design meets requirements and after assembly, a pressure test confirms that everything was built properly. When looking at Safety, a different set of criteria must be considered and many what if questions must be answered to satisfy requirements. These must seriously consider a 'train wreck scenario', for whatever multitude of cumulative errors, and review the risk of exposure to people and to assets. This paper focuses on problems associated with high pressure products with an emphasis on highlighting that design cannot end with product manufacture, but must continue beyond, to the physical testing. The Thunder Horse project requirements of high pressure and temperature with large bore piping made it imperative to check the ballistic potential of pressure caps and anything else that could possibly be unintentionally released, in a failure situation. The ballistics analyses demonstrated a number of interesting points. Firstly that existing facilities may need to be upgraded, not only for Thunder Horse, but also for less onerous work, for which we thought we were already qualified. The distances that objects could reach was surprising and in many cases would exceed the boundaries of the building or outside test site. Testing would be impractical

unless mitigation methods could be employed to reduce these projectile distances. Obviously with high pressure, a large volume will tend to increase ballistic potential and could be mitigated by using volume reducers. This is true up to a point after which the energy transfer to the 'projectile' remains constant. This phenomenon is referred to as the small plug case, where the plug is ejected before the system stored energy can be fully converted to kinetic energy in the plug. The plug outlet effectively acts to choke the flow from the vessel. The mass of the projectile will also determine distance of flight; the heavier it is, the more energy is required to move it. This presents further methods of mitigation; by adding weight, using a mass in the way of the object or using an independent locking mechanism as an extra retention device. These would be used in conjunction with an exclusion zone where all personnel would be kept far enough back, to avoid any missiles, should the unthinkable happen.

All of the above mitigation tools were strategically employed based on the ballistic results. This was done singularly or in combination as circumstance dictated. So essentially the use of ballistic calculations, not only exposed the potential dangers but also help to tailor-fit adequate counter-measures.

Ballistic Definitions & Theory Projectile Calculation.Ballistics analyses demonstrated a number of interesting points. With high pressure and large volumes there is an increased ballistic potential, and this varies exponentially from water to gas, or mixtures of water and gas. There are two issues that need to be addressed by the different media used for testing: if gas is used as the pressuring medium and a failure occurs then there will be both a projectile release and a loud sound/shock wave. If a compressed liquid at ambient temperature is being used, sound/shock waves can largely be ignored, but there still will be a projectile release. Reduction of the volume under pressure could be mitigated by using volume reducers, or by reducing the volume by selectively pressuring sections of the assembly (where possible). This is true up to a point after which the energy transfer to the 'projectile' remains constant. The mass of the projectile will determine distance of flight; the heavier it is the more energy is required to move it. Smaller objects being projected by large volumes tend to be expelled further. This then presents further opportunities to utilize other methods of mitigation, which could be achieved by adding weight, using an immovable mass or ballistic retainer matting to block travel of the object, or by using an independent locking mechanism to retain a pressure cap or

OTC-17691

Thunder Horse Ballistic Mitigation Robert McInnes - FMCTI, Robert Scott Arnold - Proforma PSI LLC, David R Wieczorek - FMCTI, Bob Brooks - FMCTI

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plug. The simplest method of all is to create an exclusion zone, around the test area, where all personnel would be kept back far enough to avoid any projectiles or fragments, should the unthinkable happen. When calculating distances projectiles would be thrown, a conservative approach is used: This assumes 100% of potential energy is transferred as kinetic energy when dealing with fluids. It also assumes 35% of available energy is transferred as kinetic energy when dealing with gases, and 65% of energy goes into the shock wave or blast associated with the failure. Pressurizing Fluid.During pressure testing the most used fluid is water, hydraulic oil or a gas such as nitrogen or compressed air. In special circumstances other fluids might be used, but results obtained using the above fluids and the following formulae, will cover most other media. The uppermost bound for fragment speed is found by applying the total kinetic energy of the vessel as the total available energy.

Total Stored Potential Energy (1)Ep = Ex + Es

Vessel Strain Energy

(2)

112213

E2VPEs 2

22

)()(

Fluid Expansion Energy

(3) 2PV2Ex

Vessel Strain Energy Compared to Fluid Expansion Energy.Vessel strain energy, as a percentage of fluid expansion energy, is higher in thin-walled vessels: Example: Subsea Flowloop Vessel strain energy is ~7% of the fluid expansion energy This is less than 5% of the fluid expansion energy for most wellhead products tested. Energy Release during Isentropic expansion of Gas

(4). WEE kp

(5).

kk

PinitPfinal*Vinit*Pinit*

kW

1

11

1

Loss of a Major Section of a Pressure Vessel.Total stored potential energy is converted into the kinetic energy of the projectile:

(6)..Ep = Ek

Where,

(7).2

**

21 V

gmEkc

Loss of Small Diameter Plugs

Limiting flow area at the hole in the vessel chokes the flow out of the vessel: (8)....Work Done =P*A*d (9). See sketch of the small plug arrangement, with Apllied Load Distance d, in Figure 1.

Figure 1: Sketch of Plug Arrangement

Where, d = (2 x B) + C m = mass of component

C = plug engagement This is sometimes referred to as the SMALL PLUG CASE

Loss of a Flange/Closure.Initial Closure acceleration away from the vessel is maintained until the fragment is clear of the vessel by an amount equal to the diameter of the hole left in the vessel. Refer to the Applied Load Distance, per Figure 1. (See REFERENCES 1 & 2) Projectile Motion

Relevant Physics.The Independence of the Vertical and Horizontal directions means that a projectile motion problem consists of two independent parts:

Vertical motion at a constant downward acceleration, which is equal to

(10)a = -g = -32.2 ft/s2 (9.80 m/s2).

C

2 x B

B

d

pc

2E

gVm

21dAP ****

OTC OTC-17691-pp 3

Horizontal motion at a constant horizontal speed, vx = constant. The object's vertical motion is the same as that of an object undergoing only vertical free-fall.

Gravitational Free Fall Generic Equation of Motion.

(11), (12)

The upward direction is taken as the positive direction. If the origin is taken at ground level, then: yo is the initial height of the object at time zero.

vy,o is the initial velocity of the object in the y-direction. An object can be given an initial vertical velocity (either positive or negative) and an initial height above the ground. Information Implied.When an object is propelled into the air, it is assumed that all other forces acting on the object except gravity are negligible. This means that: We neglect any effects due to drag resistance on the object. We neglect any effects due to the Earth's rotation. We assume that the object does not rise high enough for the acceleration of gravity to change. With these assumptions the body's acceleration is both constant and downward regardless of its direction of motion or its height above the ground. This means that object's acceleration is downwards regardless of whether the object is moving upwards or downwards;

a = -g = -32.2 ft/s2 (9.80 m/s2) Gravity only affects the object's vertical motion. Gravity cannot change the object's horizontal speed, and the component of the object's horizontal velocity remains constant throughout its motion.

Generic Equation of Frictionless Projectiles.

Vertical Motion: Constant Downward Acceleration

(13), (14), (15)

Horizontal Motion: Constant Horizontal Speed

Total Space Motion:

(16), (17)..

Figure 2: Sketch of Object Trajectory

The components of the velocity vector are shown for an object released into the air at a fixed angle.

Frames of Reference.Projectile motion problems need a two dimensional coordinate system to describe the projectile's motion. The y-direction is usually associated with the vertical motion and location of the projectile, while the x-direction is usually associated with the horizontal motion and location of the projectile.

The generic equations for projectile motion assume the origin is at ground level, up is positive, right is positive, and that the clock starts the moment the projectile leaves the ground.

Analyzing a Projectile Motion Problem.Break the problem into two independent problems by resolving the velocity vector into vertical and horizontal components Solve the two problems independently. Recombine the resulting components, if needed, to determine the object's total space motion.

Drag Force in a Medium.The force exerted on a

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body moving in a medium like air or water depends in a complex way upon the velocity of the body relative to the medium, the viscosity and density of the medium, the shape of the body, and the roughness of its surface. The most common method of mathematically modeling the drag force is the equation, (17).

The direction of the drag force is always opposite the direction of the body's velocity.

The drag coefficient CD is not constant. The CD depends upon the velocity of the body, viscosity of the medium, the shape of the body, and the roughness of the body's surface.

The Reynolds number has been found to be a useful dimensionless number that can characterize the drag coefficient's dependence upon the velocity. The Reynolds number is basically the ratio of the inertial force of the medium over its viscous force.

(18)

For small values of the Reynolds number, called laminar flow, since the flow is non-turbulent, the drag coefficient is inversely proportional to the velocity. This means that the drag force is only proportional to the body's velocity.

(19).

When the flow is turbulent the Reynolds number is large, and the drag coefficient CD is approximately constant. This is the quadratic model of fluid resistance, in that the drag force is dependent on the square of the velocity. See REFERENCE 3.

(20)

Note that the frictional force between two surfaces is an example of a situation in which the drag force is constant and does not depend upon the body's velocity or contact surface area. See Table 1 for examples of typical drag coefficients.

Table 1: Typical Values of the Drag Coefficient

OBJECT CD

Streamlined body 0.1

Sports Car 0.2 - 0.3

Sphere 0.47

Typical Car 0.5

Station Wagon 0.6

Cylinder 0.7-1.3

Racing Cyclist 0.9

Truck 0.8 - 1.0

Motorcyclist 1.8

Pressure Test Management The following section reviews the practices in place at what was considered a safety-focused organization, through the improvements and upgrades, to the actual applications of pressure test management. These were all as a result of our experience and lessons learned on the Thunder Horse project. Normal Industry Practice.Typically ballistic calculations were not carried out and although higher pressure testing was done for 15,000psi and above on a Research and Development basis, the normal manufacturing mainly covered 5,000 and 10,000psi equipment. The industry has a fairly good record on safety, however, failure events did happen and when they did they were pretty spectacular. The energy capacity related to gas testing was widely recognized and such testing was consigned to be done in a water-filled test pit. The added advantage was that leakage bubbles would be prominent. This became so blas a function that people regularly would lean over the safety railing looking for bubbles, without thought for the consequences of failure. A common practice was to hydrostatically test large assemblies in the shop area, and although cordoned off, no fore-sight on the ballistic potential, given catastrophic failure, was ever determined. Facility and Process Upgrades.Initial ballistic results highlighted the high energy potential of the 15,000psi equipment. The results were so surprising that it led to a series of upgrades within the facility. These included procedural and process checks which prohibited testing without a ballistics check sheet from engineering. During the project these ballistics results become integral to pre-test planning and HAZID studies. Guidelines were produced for calculation work with ongoing enhancements to cover sensitivities for entrapped air and dampening effects of water in the test pit. The gas test pit was fully enclosed by a wall with visual access through a reinforced window and blast curtains (see Figure 3). The gauges and plumbing were enclosed in high-impact Perspex and the use of inspection cameras became common. Now based on ballistic results, a taped off exclusion zone is defined and highlighted using a cordon of flashing lights (see Figure 4). Additionally, a strict preventive maintenance regime has been set up to encompass all test equipment. As safety awareness of the pressure testing intensified, it became obvious that we couldnt just stop on our own doorstep. Our approved vendors were selected based on audits which included safety and as our safety awareness profile increased, so we increased the audit requirements. This included the need for subcontractors to perform ballistic

OTC OTC-17691-pp 5

calculations and based on results, implement similar safety related upgrades.

Figure 1: Upgraded Gas Pit

Figure 2: Safety Cordon (flashing lights) Future Test Cell Upgrades.In the last two decades pressures have increased from 5,000psi equipment till today we are approaching 30K product lines. Typically test cells included 1/2 steel plate and cinder block walls filled with concrete and in other areas 20 of un-reinforced concrete. This is no longer enough to stop large projectiles while proof testing to 15,000psi.

The way forward is to use current High Strength Concrete Designs developed at Sandia National Laboratories in New Mexico, for Air Craft and Personnel Bunkers. A Third Party Structural Engineering Analysis was used, leading to the design of a test cell bunker system, that will be sufficient for testing large forging composite block valve assemblies up to 20,000psi . The test cell criterion was to have the walls and superstructure withstand the impact of a small high speed projectiles, without complete penetration and large high speed projectiles without collapse. Test Pressure for this design was based on 30,000psi on both large and small projectiles. In the Large Projectile event occurred there would be a minimal cost to repair the test cell; due to a multiple component design affecting only a small part of the complete test cell. It was determined that a wall thickness would be

about 10 due the space constraints and that wide access into the cell would be at least 6feet 10inches.

Using proven technology in strengthening concrete, based on Sandia Labs studies, and working with a local Concrete mixing plant it was possible to engineer a high strength composite mix. This used Bekaert Steel Metal Fiber (Trade name Dramix). For Aggregate; Davis Mountain Lime Stone from Okalahoma was used. This was both rough and hard, adding strength to the composite mix. Additionally, the steel rebar sizes were increased by 25%, and all through openings were narrowed by overlapping the rebar mats producing a 1.5inch opening.

It was estimated that the finished compressive strength of the high strength composite mix, after curing 29 days, would be 6,000psi. However, with the Davis rock and the Dramix, the overall strength of the Mix could easily double. Project-related Lessons & Improvements (Customers Perspective).As the envelope of technology and water depth continues to be pushed, so does the need to engineer larger equipment that operates at greater pressures. Therefore, testing of this equipment will continue to pose a greater safety threat to personnel conducting pressure tests. Looking at past incidents occurring within this industry, reveals a certain amount of complacency when it comes to hydrostatic testing and hazards associated with it. This complacency stems from the belief that water is incompressible and therefore its stored energy is somehow less significant than gas testing. This is why in many cases you will see the operator standing in close proximity to equipment being tested with water. As an industry we have to rapidly change this culture by utilizing science and calculations in order to quantify the hazards to personnel. The leaders in the upstream oil and gas business have gone to great lengths and expense to change the safety culture within their organizations and the contractors that work for them. However, when it comes to pressure testing equipment, they have fallen short. By conducting ballistics calculations a better understanding can be gained on how much energy is generated when liquid mediums are compressed. From these calculations one can determine stand-off distances that will take personnel out of harms way. However, in some cases when these distances are so great, shielding may have to be incorporated. Ballistic calculations help to determine what type and thickness is required to contain projectiles that have failed. From the knowledge gained from ballistics, one understands that in certain cases merely reducing volume will drastically reduce the amount of energy stored within a system, therefore reducing the distance a projectile will travel.

Of course ballistics have been utilized by militaries for centuries to design more efficient weapons as well as aid in the design of shielding to protect its personnel. In industry these calculations are an invaluable tool, which allows testing to be conducted while minimizing the impact to personnel in the event a failure occurs. There are companies that have already adopted the use of these calculations as company policy. In an industry where companies are leading the way in safety and technology, this is yet another tool that demonstrates best in class performance. To better serve the communication of safety related issues, cross-communication of lessons learned and ballistics

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methodology has been encouraged between partners in the project and often with other projects. Acceptance of the Safety Moment philosophy as a way of working, rather than simply lip-service has developed into the modulus operandi of the associated project companies. Manifold Testing Experience.The large bore manifolds (@ 500,000lbs) presented the biggest challenge for ballistic mitigation, due to their large volumes and bores and a pressures to 15,108psi. The pressure caps were all situated vertically, and a maximum offset angle of 3 was considered as being worst possible case. This enabled the horizontal component displacement to be plotted for the projectile. Volume reduction was the first mitigation challenge. This could be accommodated by stringing together a series of high density plastic reducers inside the main piping headers (see Figure 5). This helped reduce volumes between 40 and 50% only but had the disadvantage of adding time for handling, installation and retrieval to the test duration. There was also the associated risk of jamming or reducer breakage within the piping. In the Test Header, ballistic distance was unaffected, indicating the small plug case had been achieved. In the branch hubs, volume reducers could not be used because of piping configuration and because removal after testing would disturb a metal seal and render the test invalid. The branch hub pressure cap, being the smallest mass, became the pacing item with respect to potential distance that could be traveled. To reduce this to within a practical range, the branch hub volume was minimized by closing the hub isolation valves.

Figure 5: Volume Reducers

Further efforts to reduce the ballistic distance considered adding mass suspended over the caps. While being effective, it was impractical from the viewpoint of changing pressure lines and moving between hubs. A neater solution was to add a cage around the pressure cap and hub. This served as an independent locking mechanism (ILM) to that of the cap and effectively reduced the risk of sudden failure (see Figure 6). The problem here was that making the assumption of zero failure, gave no indication of ballistic distance and therefore no guidance for setting an exclusion zone. However, if we assumed that both the cap and the ILM failed, we could take advantage of half the ILM weight added to the cap. This had the advantage of severely reducing risk of failure and

allowed a workable exclusion zone to be determined.

Figure 6: ILM Capturing Pressure Cap

The same criteria could be used for the header piping and the larger pressure caps. Consequently the use of the ILMs were sufficient on their own, to allow an acceptable exclusion zone. This ensured for this particular application, the use of volume reducers was discarded. See Figure 7 for manifold ILM application.

In assessing other aspects of the testing, the small bore plumbing, and the issue of shrapnel or fragments of pipe were considered. It was concluded that the manifold structural fabrication served as an adequate shield, to potential projectiles coming from the inside. At the plumbing connection/termination points, which were at the corners, concrete ballistic blocks were strategically placed.

Figure 7: Manifold with ILMs installed

PLET Testing Experience.The Pipe-line End Termination (PLET) consisted of a mud-mat with horizontal piping ending in a bend with a vertical hub. A pressure cap would be fitted on the hub and a welded cap would seal the pipe end. Using the same methodology as the manifolds, volume reduction was first reviewed. In the case of the welded caps, the configuration meant that volume reduction would have no affect for all sizes. However it did have an effect for all sizes pressure caps, except the Test line PLET, where the small plug case was again confirmed. Similar to the manifold scenario; volume reducer installation, retrieval and risk of jamming were looked at. Additionally, the manufacturing process of welding and inspection of a tail-pipe onto the end of the PLET pipe would be complicated by the use of reducers. In the end, a decision was made to use the ILMs

OTC OTC-17691-pp 7

without volume reducers, on the PLETs. Based on the successful manifold experience, confidence was raised sufficiently to take account of 75% of the ILM weight in the ballistics calculations. The horizontal end of the pipe was protected by placing a large concrete ballast block in front of it. The overall test layout allowed several PLETs to be tested simultaneously and the concrete blocks were pre-placed to minimize test disruption. Ballistics Results The results for the Manifold Ballistics are tabulated in Table 2. This shows the results of distance traveled against mitigation efforts. The pressure caps are orientaed vertically.

The results for the PLET calculations are shown in Table 3. These show the both the vertical pressure caps and the horizontal welded test caps.

Conclusions The normal method of testing based on previous experience is no longer adequate. Ballistic analysis is now an essential tool for all pressure testing activities and must be factored into the overall design of components. This must become a fundamental in the process as testing represents the highest risk to personnel. To improve the overall safety philosophy, this methodology must be encouraged throughout the supply chain. Design of equipment should review testing implications to maximize mitigation and minimize effects of possible projectiles. This may involve structural modifications for shielding or access. Mitigation methods need to be tailored to suit each particular application and can only be properly assessed following ballistic calculation. A continuing process of improvement and vigilance is now not only a preferred option but a necessary one, based on the realization of actual ballistic potentials and consequences of failure. This includes the development of ballistics analysis to further refine the sensitivity regarding test mediums (water and gas), air in test water and damping effects of water in the test pit. Consequentially facility requirements may require upgrading, to accommodate present as well as, upcoming developments. Safety culture in an already safety-conscious environment has been raised further. This includes looking at the significance of the human factor in terms of what can possibly go wrong due to errors, lack of training or experience levels. At the end of the day four large manifolds and multiple PLETs were successfully pressure tested outside with exclusion zones. Testing was completed on schedule with no incidents. Nomenclature A = Cross-sectional Area perpendicular to the flow. ft2 a = acceleration B = bore of plug hole C = plug engagement CD = Drag Coefficient. SI: Dimensionless (See Table 1) d = applied load distance E = Youngs Modulus of Vessel Material Ek = kinetic energy immediately after launch Ep = Total Stored Potential energy

Ex = Fluid Expansion Energy Es = Vessel Strain Energy FD = Drag Force lbf K = Cp / Cv, ratio of Specific Heats L = Characteristic length of the body along the direction of flow. ft m = mass of component P = Final Pressure Pinit = initial pressure Pfinal = final pressure Re = Reynolds Number (dimensionless) V = Internal Volume of the Vessel v = velocity of body relative to the medium ft/s Vinit = initial volume of system W = work done during expansion = Ratio of outside to inside diameter of the vessel = Compressibility of Water = Poissons Ratio = Density of the medium. lb/ft3 References

(1) Saville G., Richardson S.M. & Skillerne de Bristowe B.J. Pressure Test Safety UK Health & Safety Executive, 1999 CRR 168/1998 HSE Books, Sudbury, Suffolk. Prepared by the Department of Chemical Engineering Technology, Imperial College, London and BJS Research, Reading. Health and Safety Executive (HSE) is responsible for the regulation of almost all the risks to health and safety arising fromwork activity in the United Kingdom (Great Britain).

(2) FMC Design Guidelines G03.04 and G03.05 (3) Projectile Motion with Air Resistance,

Department of Physics, Indiana University, Bloomington, IN.

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Table 2: Manifold Ballistic Data

Manifold Component

MITIGATION CONDITIONS Test Pressure

psig

Cap Weight

lbs. Volume in3 X-Axis Travel ft.

Y-Axis Travel ft. 50% ILM

Weight Volume Reducer

Pigging Loop

12 W.I. Header

No No N/A 12,500 1,324 92,900 398 82

Yes No N/A 12,500 3,074 92,900 177 36

No No N/A 12,500 1,422 92,900 1666 348

Yes No N/A 12,500 3,172 92,900 753 156

No Yes N/A 12,500 1,422 58,162 688 143

8 Test Header

No No No 15,108 1,372 34,206 653 135

Yes No No 15,108 3,072 34,206 293 60

No Yes No 15,108 1,372 24,230 653 135

No No Yes 15,108 3,072 41,534 653 135

No Yes Yes 15,108 3,072 41,534 293 60

12 Production Header #1

No No No 12,563 1,422 92,043 1675 350

Yes No No 12,563 3,172 92,043 756 157

No Yes No 12,563 1,422 45,354 544 112

No No Yes 12,563 1,422 119,485 1675 350

Yes No Yes 12,563 3,172 119,485 756 157

12 Production Header #2

No No No 12,563 1,372 86343 1735 362

Yes No No 12,563 3,122 86,343 768 159

No Yes No 12,563 1,372 47,672 591 122

No No Yes 12,563 1,372 106,460 1735 362

Yes No Yes 12,563 3,122 106,460 768 159

5 Valve Cluster

No No N/A 15,108 155 13,451 3357 702

Yes No N/A 15,108 1,905 13,451 282 58

12 Pigging Loop

N/A No Pig Loop Test 12,563 13,659 40,234 59 11

N/A No Manifold +AIR 12,563 13,659 119,485 183 37

8 Pigging Loop

N/A No Pig Loop Test 15,108 10,489 14,650 33 5

N/A No Manifold +AIR 15,108 10,489 106,460 281 57

Pig Loop Test Stand N/A No Stand Test 12,563 5,869 40,234 126 25

Valve Cluster & Test Header

FULL VOLUME - Ductile/Brittle Failure @weld 1% to 20% fragment 15,108 N/A 7,010 4459 931

W.I. & Production Headers

FULL VOLUME - Ductile/Brittle Failure @weld 1% to 20% fragment 12,563 N/A 47,672 3698 774

Table 3: PLET Ballistics Data PLET

Component

MITIGATION CONDITIONS Test Pressure

psig

Cap Weight

lbs. Volume in3 X-Axis Travel ft.

Y-Axis Travel ft. 75% ILM

Weight Volume Reducer

Hub or Pipe

12 Pressure Cap

No No Hub 12563 1422 109967 1429 298 No Yes Hub 12563 1422 43730 525 108 Yes No Hub 12563 4047 109967 497 96

12 Test Cap No No Pipe 12563 257 109967 N/A 213 No Yes Pipe 12563 257 43730 N/A 213

10 Pressure Cap

No No No 12500 1738 78267 711 147 No Yes No 12500 1738 28165 279 57 Yes No No 12500 4363 78267 384 75

10 Test Cap

No No Pipe 12500 200 78267 N/A 187 No Yes Pipe 12500 200 28165 N/A 187

8 Pressure Cap

No No Hub 15108 1701 41388 413 85 No Yes Hub 15108 1701 21010 413 85 Yes No Hub 15108 4326 41388 413 85

Test Cap No No Pipe 15108 146 41338 N/A 347

No Yes Pipe 15108 146 21010 N/A 233