After selecting material and valves (discussed previously), the next step is to ensure proper piping layout and design[1]. This process will be iterative, even requiring a return to material selection in some cases, as the physical design can uncover issues not foreseen when looking simply at a schedule or process diagram. The following are a number of important considerations in designing process piping systems:

Piping Layout & Design Considerations for Installation

1. Plan a degree of freedom. When fitting skids, tanks, pumps, and other equipment together in the field, it’s inconvenient to find centerlines off by an inch. Plan a pipe route that does not rely on unrealistically precise placement of large equipment with no plan for what happens if the concrete or other mounting surface isn’t perfect.
2. When designing and planning pipe routes that may be difficult or impractical to install, consider the contractor who must build the pipe system.
3. Plan clean routes. Not only do mechanical contractors need to connect the pipe system, they also need to provide adequate support. A straight and organized piping system is easier, faster, and cheaper to build and support.  Straight runs are cheaper than elbows. Joints are time consuming no matter what the material.
4. Measure twice, cut once. Appearance should matter to all involved.

Maintenance/Serviceability

1. Place valves where they can be easily reached to avoid situations in which operations staff are inconvenienced by pipe location or other equipment.
2. Once assembled, can the system be disassembled or removed for servicing? For example, if a valve were threaded between two parallel pipes, and then long runs of pipe on either side were installed, all the pipe would have to be taken apart just to unthread that valve. Unions or flanges should be used whenever possible.
3. Consider how piping will drain when opened for servicing.
4. Build manageable pipe sections. The cost of two extra flanges or a union may be well worth it considering the difficulty of assembly of complicated systems. Also, consider maintenance requirements for that pipe; removable sections facilitate any required changes and save time and money.

Functionality/Performance/Flexibility

1. Consider what happens if a valve fails, a tank overflows, or a syphon starts.
2. Consider the suction requirements of pumps and design suction lines appropriately. All pumps are susceptible to cavitation, which has important consequences.
3. Pipe friction matters. Need a drain to keep up with the inflow? Consider the head required to drive the required flow.
4. Keep a certain distance between a pump discharge and check valve. A pump discharge may be much smaller than the pipe it is connected to. This leads to high velocity, which can be fatal for a check valve. For a typical centrifugal pump, it is best to use an expander to go up to the right pipe size and then install a check valve. This protects the check valve internals from high velocity flow. If the check valve is installed too close to the discharge, the internals may be damaged or missing entirely after they’ve been in service.
5. If there are plans for future equipment additions or piping system expansion, consider ending headers with a flange instead of a cap.
6. Pipes may need to be insulated to prevent heat transfer or formation of condensation. However, remember that insulation does not equate to freeze proofing. What happens when a process is left inactive during freezing temperatures? Heat tracing outdoor lines can be an important safety measure.

There are numerous types of pipe joints — selecting the best one for each application requires careful consideration. The following are some tips to help avoid costly mistakes on three of the most commonly used joint types:

1. Threaded joints, such as NPT, are widely used and can be a great long-term reliable solution if applied correctly. Since they do not use elastomers to seal, they are more likely to develop leaks for a variety of reasons, from improper cutting of threads; lack of or incompatible sealant; or deformation of threads due to stress, expansion, and contraction or even material failure from overtightening, as is common when threading metals into plastics. Consider the media being utilized. When working with NaOH or NaOCl, it is common practice to never use a threaded fitting. Many chemicals have a tendency to weep through threads and form scale that never stops growing.
2. Flanges are typically very reliable and easy to seal with the appropriate gasket yet, if used improperly, can cause numerous problems. Flanges require the pipe and bolt holes to align properly. When possible, at least one rotating flange ring on a joint should be used to allow a degree of adjustability to the joint for installation. This is especially true if a valve or other device is to be bolted in between the flanges. Most pumps will have a fixed flange ring cast as part of the volute or housing, so it is very helpful to have a rotating flange ring, such as a slip-on or van-stone style, to allow for rotational adjustments.
3. Grooved pipe fittings can be very useful, but like any other joint, they need to be properly installed. Grooved couplings to pull pipes together or into alignment should always be avoided. Like all joints, when the coupling or bolts are removed, the pipe should remain in alignment on its own.

All piping must be held in place, whether on the floor or hanging from the trusses. Planning piping support is equally as important as piping routing. The following are some items to consider for planning supports:

1. Structural steel (or other support material) should support the piping, not the other way around.
2. Pipe hangers may hold the static weight of the flooded piping, but fluids flowing and stopping inside the pipe will impose dynamic loads and can cause it to move laterally if not properly restrained. This puts stress on the pipe and joints which in extreme cases can cause failures.
3. Appropriate supports must be used. Never assume that a two-piece strap on a vertical pipe is supporting the weight of that pipe. It may keep the pipe against the wall and support the weight short-term, but it may also slide down over time, particularly where there are vibrations. Plan proper load-supporting clamps, especially in cases where non-metallic pipe straps are used for vertical support.
4. In many cases, it is unrealistic to expect that equipment and piping will be held perfectly still. In these cases, having joint flexibility built into the piping (by using bellows, for example) can allow some movement without compromising rigid joints or welds.
5. Proper pipe restraints are critical when using a pulsating pump, such as a piston or diaphragm type. Connecting the pump to piping by a hose and installing a pulsation damper will reduce surge and pipe movement but won’t stop it entirely.
6. Consider thermal expansion impacts.
7. When properly built, piping should not need the flange bolts to hold the right alignment. Avoid clamps and bolts to pull pipes into alignment, as this can cause cracks and failures.
8. Drains need supports too. Since they are typically empty, drains may be lightweight and hold straight. This will not, however, be the case if a clog forms and the pipe fills with liquid.
9. Avoid using flanges as a support point, even though they are convenient bolt holes with heavy-duty bolts. Mixing a mechanical support with a pressure rated joint could have serious consequences when maintenance on the support or tampering with the joint is required.

[1] Fluid mechanics and piping systems pressure drop calculations are core to piping sizing and design. Friction loss in piping systems is dependent on pipe diameter and material, and fluid density, viscosity, and velocity. This aspect of piping systems design is not addressed in this article.

__________________________________________________

Integrated Technologies, Inc. is an industry-leading engineering, design, and consulting solutions firm based in Burlington, VT. We offer project planning and development, full-service engineering and design, project and construction management, and services during construction to the surfacing finishing and industrial manufacturing industries. 

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Once material selection of the process piping systems has been considered (discussed previously), valves, fittings, and other components need to be selected for the process. The following explores the subtle details of valve selection that can make a difference in the long-term success of the process piping systems and hence the overall process line itself.

The most important step is to understand the purpose of the valve. Once that is established, the material, internal function, and cost of each potential option should be evaluated. There are valves for specific functions, such as shutoff, throttling, redirecting, backflow prevention, retaining pressure, reducing pressure, releasing air, and preventing syphoning. On the surface, the purpose of a valve may seem simple and many valves may appear adequate; however, selecting the best option takes experience. The following scenario illustrates the importance of reviewing all options:

Two parallel pumps draw water from an elevated tank and pump the water to a number of process machines or systems at low pressure. To prevent water from backflowing through a pump when one is running and not the other, a check valve must be installed on the discharge of each.

There are many types of check valves, including swing, folding disc, ball, lift, y-pattern, and cone check valves. Each has strengths and weaknesses and can serve specific purposes. In addition, there are many options for modifications and enhancements, such as spring-assisted closure, external movement dampers, and adjustable cracking pressure. In the above parallel pumping scenario, as only backflow must be prevented, it would be easy to assume that any check valve would do; therefore, the tendency might be to pick the cheapest option. Other factors, however, must be considered. For example, given the fact that the tank is elevated, were a leak to develop downstream or if a valve were left open by mistake, it could flow by gravity while the pumps are not running, resulting in a flooded room. This risk could be avoided by installing a check valve with a heavy spring to set the cracking pressure at or above the head produced by the full tank of water. As long as the pump is running, the cracking pressure would be overcome and the water could flow. However, as soon as the pump turns off, the spring would force the valve closed, preventing both back flow and leakage or syphoning.

Thorough consideration of the function of the valve and all of the possible scenarios is always appropriate, even for shutoff and throttling. Valves with open/close functionality seem simple, yet the application should be considered. For example, the valve may need to open and close very quickly, or it may be critical that the valve open and close slowly to avoid shocking the piping system or to precisely control flow.

With higher velocity flow, the risk of water hammer becomes real. Despite the name, water hammer is not exclusive to water; it is caused by sudden changes in fluid flow, usually due to rapidly accelerating pumps or fast-acting valves. Water hammer can cause pipes to move violently, often leading to failures at joints. For example, it would be risky to put a manual, lever-actuated butterfly valve in a pipe with high velocity flow, as it would enable an operator to quickly shut the valve, causing water hammer and potentially damaging the valve or the piping. In this case, a valve with a multi-turn actuator, such as a gear reducer, would ensure that the valve actuation is slow and gradual.

When throttling valves, it is common to see ball or butterfly valves used, due to their relatively low cost. Unfortunately, these types of valves do not typically provide fine control of flow. The use of a valve, such as a globe, diaphragm, or gate valve, with multi-turn adjustment and a linear relationship between percent open and flow is more appropriate. These types of valves will typically have a wheel-shaped handle that allows several full turns, from fully open to fully closed. Although these valves will tend to be more expensive, the importance of flow control must be weighed against the cost.

Most types of valves can also be fitted with pneumatic or electric actuators to allow the valves to be controlled remotely or by an automation system for flow regulation or on/off service. Actuators can be outfitted with a variety of features, such as open/closed position feedback switches, analog positioners and position feedback outputs, visual position indicators, travel time adjustments, battery backups for power failure response, and more.  Wiring of these types of actuators can be done by hard wiring each input and output to the process automation system or by network or bus systems, such as Modbus, PROFIBUS, DeviceNet, or Ethernet. Using network solutions can be highly advantageous, especially with large numbers of valves and multiple control inputs and outputs per valve.

The function of the actuator is also important. Engineers must consider the torque required, rated duty cycle, movement rate, inputs and outputs available for control, materials, IP or NEMA rating, and cost. If a problem is encountered that can only be solved by replacing or upgrading the valve or actuator, the replacement may mean much more than the cost of the parts, including labor, down time, lost production, and potential fitment issues after an installation is complete and running. In many cases, replacing a valve can necessitate fully draining a process system if isolation is not possible or practical. For these reasons, proper advance consideration of all factors to correctly select application-specific valve and actuator types is essential.

__________________________________________________

Integrated Technologies, Inc. is an industry-leading engineering, design, and consulting solutions firm based in Burlington, VT. We offer project planning and development, full-service engineering and design, project and construction management, and services during construction to the surfacing finishing and industrial manufacturing industries. 

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If you’ve received this email, you opted in to receive the Integrated Technologies, Inc. email newsletter at some point in the past.  We only store your email address and name with the sole purpose of sending you our email newsletter on a quarterly basis.

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In addition to reviewing specifications, codes, and standards, engineers and design technicians must also apply practical knowledge and experience to develop process piping designs that are cost effective, reliable, serviceable, and easy to build. Codes are simply a minimum requirement, and compliance doesn’t guarantee optimal design.  Following codes will usually result in safe solutions – that is the point of the codes – but process piping design expertise is important to achieve good constructability, process operability and maintainability, and to avoid conditions that may be detrimental to a specific process. As new materials, devices, and processes are developed, so too should work methods and design principles. This three-part series will present some practical ideas for new piping installations that will aid in building a cost-effective and well-thought-out facility.

When deciding which pipe system is best for an application, the material is usually the main focus. A range of piping materials, including metallic piping (e.g., carbon steels, stainless steels, nickel alloys, titanium and zirconium), plastic piping (e.g., PVC, CPVC, PP, and PVDF), composite piping (e.g., FRP and advanced composites), and lined piping (e.g., plastic or glass-lined metal or plastic-lined FRP), are used to meet specific process piping application requirements. Industrial and chemical process plastic piping is typically Schedule 80 (SCH 80) with greater wall thickness and pressure/temperature operating range than SCH 40 piping (commonly used for domestic applications).

First, evaluate the chemical compatibility with the material choice, taking into consideration the expected fluid properties and system design life. The selection of piping system materials requires careful evaluation of all possible internal fluid scenarios (including range of typical operations, operating extremes, and start-up, shutdown, and upset conditions) and external exposure and environmental factors.  It is not uncommon to have widely varying conditions inside a process piping system. There may be large swings in pressure, flow, temperature, pH, chemical concentrations, or other factors that may affect the piping and other wetted components. Therefore, it is important to evaluate the potential minimum and maximum extremes and compare them with the pipe and component ratings. Reviewing these potential conditions may well avoid a costly accident in the future.

For example, the introduction of unexpected conditions as a chemical dosing pump is injecting a small amount of acid into a pipe flowing water at 40 psi could result in widely varying scenarios:

Scenario 1: An operator closes the valves on either side of the injection location while the pump is operating. The dosing pump is capable of delivering at up to 250 psi, so line pressure quickly jumps from the usual 40 psi to 250 psi, causing a joint to crack and leak. With minimal flow in the dosing pump, the crack can go unnoticed until the valves are opened again and water begins to flow causing a spraying leak. Practically speaking, this could be avoided by implementing a pressure relief valve; however, it is always best to design a system to be inherently safe, using mechanical devices for supplemental protection or for convenience.

Scenario 2: The water flow stops and the dosing pump continues to pump acid, dropping the pH in the area of the injector to levels low enough to damage the material of the pipe or elastomers. This is an instance where the design fluid properties after mixing would suggest the materials were suitable, but the unexpected extreme drop in pH caused the piping to degrade and fail.

In this example of chemical dosing, the heat of the reaction at the dosing point must also be taken into account. Introducing acid into PVC pipe full of water can yield a sharp temperature increase and, if the water is not flowing, the heat build-up could have important consequences.

Secondly, when evaluating material suitability for the maximum design temperature and pressure, it is critical to review both together rather than independently. Pressure ratings on piping are temperature-dependent, as the material strength (most importantly, tensile) drops with temperature increases, reducing the total pressure the material can withstand before failure. Often, pipe manufacturers will publish a table with a maximum working pressure for each size pipe at 70 to 80°F. For temperatures higher than this, a table is usually provided with derating factors which must always be used to check the pipe selection for an application. It is important to remember that the average conditions are not sufficient to verify correct material selection; maximums must be considered, even if they are rare. In some cases (e.g., for some plastics), minimum temperatures and durations are important, as some materials can embrittle at low end temperatures at or below freezing and become more susceptible to damage/failure.

A common material selection mistake is the use of PVC instead of CPVC for elevated temperatures. The pressure rating of most PVC and CPVC is the same at room temperature and PVC is less expensive, making it an attractive choice. For this reason, erroneous premature decisions to use PVC are sometimes made before evaluating the pressure rating of the PVC pipe at maximum expected temperature. PVC has a steeper derating curve, causing it to have lower pressure ratings at elevated temperatures than CPVC. For example, 2” SCH 80 PVC and CPVC pipe is rated at 400 psi at 73°F, but at 120°F, the derating factor is 0.4 for PVC, but only 0.65 for CPVC. This means that at 120°F, SCH 80 PVC is rated at 160 psi, while SCH 80 CPVC is rated at 260 psi.

The environment outside of the pipe is another design criterion that is often overlooked. In most cases, there are no adverse effects from the ambient conditions outside the pipe, but it must always be reviewed. A potentially serious environmental influence on plastic pipe systems is UV light. If a pipe is run outside with exposure to the sun, over time the UV light can degrade certain materials, particularly plastics or non-metal coatings. This can lead to discoloration, chalking, or even embrittlement. If it is impractical to provide protection from the sun, then the best option is to select a material that is UV stable.

Piping in industrial settings may also be regularly exposed to chemicals, such as fuming acids or oxidizers. This can lead to corrosion on the outside of piping systems, particularly metals, though many plastics can be susceptible to degradation from fuming chemicals as well.

Many systems will require pipe materials to change in certain sections depending on the environment they are to be used. For piping transitions between dissimilar metals, galvanic corrosion may result due to the electromotive force generated by the galvanic cell from the dissimilar metals. This can be minimized by using a nonconductive barrier such as a dielectric union.

By taking a more thorough look at the environment, and possible conditions a specific pipe system will be subject to, some unexpected and potentially expensive short-term or future issues can be avoided.

__________________________________________________

Integrated Technologies, Inc. is an industry-leading engineering, design, and consulting solutions firm based in Burlington, VT. We offer project planning and development, full-service engineering and design, project and construction management, and services during construction to the surfacing finishing and industrial manufacturing industries. 

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ITI’s GDPR Privacy Policy

If you’ve received this email, you opted in to receive the Integrated Technologies, Inc. email newsletter at some point in the past.  We only store your email address and name with the sole purpose of sending you our email newsletter on a quarterly basis.

You can change your mind at any time by clicking the unsubscribe link in the footer of this or any email you receive from us, or by contacting us at  [email protected].

We will treat your information with respect. For more information about our privacy policy and practices please visit our website http://www.processengineer.com/privacy-policy/

Capital and operating and maintenance (O&M) cost estimates are important for project planning, development, and implementation for building new process lines or for renovating/replacing existing process lines. With an overview of AACE International capital cost estimate classifications and considerations for cost estimates over the life cycle of a project now established, we can focus on critical scoping and cost estimating considerations in the early planning and development for surface finishing process projects.

Understanding key considerations for surface finishing process projects can help guide implementation towards desirable life cycle cost optimization and avoid the following:

• Inadequate early budgets (a frequent problem that results in project constraints and increased life cycle costs).
• Insufficient allocation of time and resources essential for optimization planning and design.
• Lack of scope definition that can result in costly higher construction change orders and project implementation impacts and/or reductions in overall project delivery.

Surface finishing project optimization involves much more than simple line-by-line equipment replacement, particularly for renovation projects. For optimum project outcomes, initial project cost estimates and budgets should account for important process considerations that should be evaluated early in project development, including the following:

• Schedule: Unrealistic project schedules can significantly drive up project costs considerably and limit the pool of resources available to support the project.
• Project Phasing: Phasing logistics must be effectively planned for all affected surface finishing process lines and ancillary systems areas. Phasing plans should minimize any production downtime and avoid the need for temporary production outsourcing, if possible.  Early cost allowances should consider project phasing logistics and schedules.
• Master planning: Master planning of the scope and schedule of related plant-wide projects is critical to avoid unnecessary costs and interruptions caused by lack of planning between different project managers.
• Accommodations for future flexibility: Considerations for future process flexibility may result in modifications to surface finishing designs, such as leaving space(s) for future process expansion or changes or designing selected process configurations and materials of construction to meet future process expansion/modification needs. Accommodations for future process flexibility can increase current project capital costs but may yield substantial savings while reducing production disruptions caused by future process changes.
• Effective layout and configuration of surface finishing lines and processes for optimum operability and maintainability: This requires a thorough understanding of flows of work, material, and people with consideration of current and future production sequences. Process mapping can facilitate right-sizing and arrangement of process lines for flexible production of different processes, substrates, and load sizes with variable production rates, load configurations, and handling requirements. Ideally, plant design follows process design and arrangement of process lines; however, designers normally must develop plant layouts under constrained conditions. Perceived and real constraints must be identified early to optimize projects based on realistic cost estimates.
• Process and equipment redundancy: Redundancy, including multiple processing tanks and duplex pumps and other critical equipment, systems, and spare parts can significantly increase project costs. Certain levels of redundancy may be needed to achieve desired process reliability and minimize the potential for process downtime.
• Materials of Construction, Component Selection & Quality of Equipment: Incremental upgrades, and overall quality of equipment and robustness of materials of construction selected, can increase capital costs, but may provide significant increases in equipment longevity and performance that provides strong cost payback. Getting this right in the design phase can dramatically reduce overall life cycle costs by minimizing unplanned process disruptions and replacement of lower cost equipment or materials that can’t provide longer term performance in the specific application.
• Level of Automation: Incorporating load handling and processing automation and integration of process monitoring and notification systems will increase capital costs but can provide significant enhancements to production capacity and capability and yield significant life cycle benefits.
• Utilities and Ancillary Systems: Current and future utilities and ancillary systems requirements, including process water and wastewater treatment, air pollution control, makeup air, and process heating and cooling, must be sized appropriately. Considerations include whether utilities and ancillary systems should be updated, replaced, or relocated to meet production needs, energy efficiency goals, or to improve workflow. Replacement with right-sized systems, and improved integration with new surface finishing systems, can provide strong cost paybacks and also systems performance benefits.

The above and additional key process scoping issues, as applicable to a specific project, should be considered in early surface finishing project planning, with appropriate subject matter experts and diverse project stakeholders, and then analyzed in more depth and optimized after developing a more comprehensive project vision. Early insights to optimize project scope and recognize important constraints, such as business interruptions and schedule issues, provide a better foundation for establishing an early Basis of Estimate (BOE) for a surface finishing project and a more informed understanding of project cost estimate ranges, risks, and cost optimization opportunities.

Consider the AACE cost estimate classes for early project development for Class 5 and Class 4 estimates and that the expected range of accuracy for each estimate is based on the maturity and accuracy of scope definition at the time of the estimate. The surface finishing process considerations above show why a combination of multiple project scope options and costs, cost allowances for scope variables, and appropriately broad cost accuracy ranges should be evaluated for early surface finishing process project cost estimates. Improved early understanding of potential project scope variables, and associated costs and benefits often leads to improved overall project implementation and life cycle cost-effectiveness.

The following are examples of enhanced surface finishing project outcomes resulting from improved early project scoping considerations:

• A decades old large US DOD plating shop with over 100 process tanks was completely renovated with a strong cost payback, after identifying that exhaust ventilation and makeup air systems could be downsized by more than 90% by replacing old manual surface finishing process lines with new reconfigured automated lines, including right-sized process tanks with automated covers and sophisticated controls with energy savings from control of production operating
• A project for adding a new wastewater treatment system for an automotive parts manufacturer with four aging process lines was transformed, after an initial project scoping workshop, into a project that included the replacement of the four process lines with new, high-efficiency automated lines. The new, efficient surface finishing process lines resulted in more than 85% reduction in wastewater generation. The production capacity was also tripled with process automation and by improving layout and workflow. The savings in downsizing the wastewater treatment system funded almost 40% of the new process lines, and the overall production capacity and quality enhancements resulted in rapid payback for the incremental project investment.

Relatively minor investments in up-front surface finishing project scoping and cost estimating can lead to significantly enhanced project delivery with strong life cycle benefits.

__________________________________________________

Integrated Technologies, Inc. is an industry-leading engineering, design, and consulting solutions firm based in Burlington, VT. We offer project planning and development, full-service engineering and design, project and construction management, and services during construction to the surfacing finishing and industrial manufacturing industries. 

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ITI’s GDPR Privacy Policy

If you’ve received this email, you opted in to receive the Integrated Technologies, Inc. email newsletter at some point in the past.  We only store your email address and name with the sole purpose of sending you our email newsletter on a quarterly basis.

You can change your mind at any time by clicking the unsubscribe link in the footer of this or any email you receive from us, or by contacting us at  [email protected].

We will treat your information with respect. For more information about our privacy policy and practices please visit our website http://www.processengineer.com/privacy-policy/

Capital and operating and maintenance (O&M) cost estimates are important for project planning, development, and implementation when building new process lines or for renovating/replacing existing process lines. With an overview of AACE International capital cost estimate classifications now established, we can discuss considerations for cost estimates over the life cycle of a surface finishing project.

Table 2 below shows capital cost accuracy ranges at the lowest and highest expected certainties for each of the five (5) AACE cost estimate classes for an example aerospace surface finishing project with a capital cost expected value, assumed to be constant for each estimate class, of ten million dollars ($10.0M).

TABLE 2: AACE Low and High Expected Ranges for Surface Finishing Project
Expected Value Capital Cost Estimate of $10.0M

NOTE: In millions of dollars (including contingency). See Table 1, Part 1 for AACE range percentages.

Table 2 shows large differences in accuracy ranges for each AACE Estimate Class from, lowest to highest certainty levels.  Note that the cost ranges are the same (around the $10.0M estimated expected cost) comparing a Class 5 estimate with high certainty and a Class 3 estimate with low certainty and also comparing a Class 4 estimate with high certainty and a Class 2 estimate with low certainty. As discussed in the March 2019 AACE 18R-97 reference for process industries:

• For complex or risky projects, the cost uncertainty ranges can increase by 2x to 3x.
• Estimate accuracy ranges can be impacted by systematic project risks, including: level of familiarity with technology, unique/remote project locations and conditions and availability of relevant cost data, project complexity, quality of reference cost data, quality of cost estimate assumptions, estimator experience and skill, estimating techniques and budgeted time and effort, market and pricing conditions, currency exchange, and accuracy of process definition.

The following lists, for each AACE cost estimate class, typical percentage completion of surface finishing project engineering deliverables (in parenthesis – see Part 1 for full ranges), key project engineering definition at the time of the estimate, typical cost estimate methodology and typical estimate uses:

• Class 5 (2%): Initial project high-level scoping walk-through and owner discussions are complete and preliminary surface finishing project location, automated processes and process lines (anodizing line, nickel plating line, and specialty electroless and electroplating line), and ancillary systems to be included in the project identified. A Class 5 capital cost estimate is prepared based on extrapolation/interpolation from completed costs from similar projects, with adjustments for comparative scope differences and cost factors, such as project location, complexity, and inflation, over time. Class 5 capital cost estimates are used to identify potential alternate project scenarios and for some initial project screening and strategic business planning.
• Class 4 (15%): Process sequence diagrams are complete for surface finishing processes, and preliminary process flow diagrams are complete for surface finishing and major ancillary processes. Preliminary layouts and elevations are developed to assess space requirements and clearances. The Class 4 capital cost estimate is used to confirm project feasibility, to select or narrow major process/configuration options, and for preliminary budgeting.
• Class 3 (30%): Process deliverables, including piping and instrumentation diagrams (P&IDs), major equipment lists, functional description, preliminary 3D model, and energy and material balances are developed to a point where the process design basis is “frozen”, allowing subsequent release to multi-discipline engineering design team to develop design details. The Class 3 estimate is prepared using line item costs for major equipment and systems, plus percentage or lump sum line items and allowances for balance of systems (e.g. miscellaneous mechanical, electrical, and I&C), installation, freight, taxes, engineering and professional services, and markups that are based on similar project/location experience. The Class 3 capital cost estimates are often used to support full project funding requests and for initial project budget and schedule controls (until replaced with more detailed estimates). From the March 2019 AACE International 18R-97 reference for Process Industries, “In many owner organizations, a Class 3 estimate is often the last estimate required and could very well form the only basis for cost/schedule control”.
• Class 2 (60%): An intermediate level 3D model and intermediate design deliverables for all engineering disciplines are complete, including plans, schedules, and lists, with the final level of details to be added following Intermediate Design review. The Class 2 estimate is prepared using detailed cost line items from vendor quotes and relevant cost references. For scope areas still remaining to be detailed, assumed levels of line item breakout and detail takeoff (forced detail) are used. The Class 2 capital cost estimate is used as the detailed contractor control baseline.
• Class 1 (95%): All Pre-Final engineering design documentation is complete, including detailed 3D model and process, structural, mechanical, electrical, and instrumentation and control (I&C) drawings, specifications, schedules, diagrams, and lists. The Class 1 estimate is prepared using detailed line item breakouts for all relevant project scope areas and using quantities measured or calculated in the design documentation. The Class 1 capital cost estimate is used by owners and contractors to support the change management process and for vendor/contractor negotiations. The Class 1 capital cost estimate is used by construction contractors to support their bids and for final control baseline and change management support.

Setting surface finishing project scope early is important to establish sufficient budgets and to avoid project disruption in detailed design phases. Early consideration of process equipment quality and durability, robust materials of construction, critical equipment and systems redundancy, project phasing and delivery logistics, and flexibility for future production and process changes are important to avoid oversights and shortfalls on project budget planning.  Potential project scope variances for surface finishing projects should be identified based on a depth of industry process experience and alternatives with separate cost estimates should be developed where applicable. Project life cycle costs can be minimized by cost-effectively adding capital costs for systems and quality that minimize future process/production disruption and maintenance/repair costs, as well as reducing costs for anticipated future process modifications. Expert cost estimating and process engineering support, through the development and delivery of surface finishing projects are valuable for defining and expediting quality projects with strong life cycle benefits.

__________________________________________________

Integrated Technologies, Inc. is an industry-leading engineering, design, and consulting solutions firm based in Burlington, VT. We offer project planning and development, full-service engineering and design, project and construction management, and services during construction to the surfacing finishing and industrial manufacturing industries. 

__________________________________________________

ITI’s GDPR Privacy Policy

If you’ve received this email, you opted in to receive the Integrated Technologies, Inc. email newsletter at some point in the past.  We only store your email address and name with the sole purpose of sending you our email newsletter on a quarterly basis.

You can change your mind at any time by clicking the unsubscribe link in the footer of this or any email you receive from us, or by contacting us at  [email protected].

We will treat your information with respect. For more information about our privacy policy and practices please visit our website http://www.processengineer.com/privacy-policy/