Build to Test — The New Standard in Industrial Piping Construction
By: Gary Orton
Tags: Piping, Piping Engineering, Construction Management, Construction Industry, Construction

There is an old, and commonly iterated tale, about a scorpion crossing the river on the back of the frog. The frog is reluctant at first, knowing the nature of the scorpion; but, he’s eventually convinced by the argument from the scorpion that its deadly sting would bring about their mutual end by drowning. Long story short, the scorpion stings the frog during the crossing at mid-point. The frog utters his last words, “seriously, now we’ll both die”; the scorpion replies “I know, but it’s my nature”.

Nature Versus Nurture

One puzzling example of the ingrained nature of industrial construction project delivery is how we pressure test our piping systems. We invest significant effort during construction in connecting spools, installing studs, nuts and gaskets, and torqueing flanges. We then return, often shortly after, to crack those same flanges, remove the studs, nuts and gaskets, and install test blinds. After testing, we then return to crack those same flanges again, remove the test blinds, install new studs, nuts and gaskets, and retorque the flanges. See the problem? When you actually walk through the sequence of steps, it seems ridiculous to construct that system twice. Yet, we do it on almost every industrial project.

This approach, which was once acceptable, is nothing short of out-of-sequence planning or planned rework. In lean terms, it’s over-handling. There’s no value in doing the same work twice. So, innovative teams are working to eliminate redundant steps through investment in early system test planning. Early planning efforts yield clear advantage to contractors willing to challenge the status quo. By eliminating unnecessary tasks, improvements in safety, schedule, budget and quality performance may be realized. This approach can also have significant influence on project bid outcomes.

In the past, this early planning would have appeared overwhelming. It’s far more difficult to plan test limits with stacks of early design drawings. But we are no longer constrained by that challenge. By leveraging digital tools, teams can invest more significantly in front-end planning than they have in the past. Teams that are doing so are surpassing their competitors who are content with the nature of traditional project delivery methods. The digitally-powered teams are nurturing new ways of doing business, challenging nature at its most primal elements. They’re nurturing new ways of planning and executing construction projects.

Not that long ago, quality control teams didn’t have the strict controls they have today. Not every connection required a visual inspection for interior foreign material, flange faces for damage, bolt-up alignment, gasket spec conformance, etc. Safety, as with quality control, was in its infancy decades ago; scaffolding was built to different standards and inspected less often. Construction workers walked steel beams without the safety of fall protection equipment. Confined space work was conducted without the sophistication of advanced atmospheric monitoring equipment. The skill qualifications, permitting, and complex workflows practiced by construction teams today have advanced by leaps and bounds compared to past times. Yet, some dated practices still remain. One of those practices is the way we build and test piping systems.

So, What’s the Problem?

Modern flange bolting processes follow exact torque and tension criteria with precise sequencing. Every step in the exercise is measured and checked for accuracy and quality. Specifications are dictated with the highest degree of diligence, and qualified professionals with college and university diplomas and degrees determine the ways and means of product delivery. Information is now received, recorded, and reported by technicians at every step.

The result of these flange management workflow improvements is enhanced quality and safety performance. Our products are safer, last longer and perform better than they have in decades past. Instead of using phrases like ‘hammer it until it rings and sings’, we use terms that include flawless, best-in-class, and zero tolerance. We have invested heavily in improving the quality and safety processes that resulted in past losses; however, we haven’t kept pace with planning and sequencing methods of flange management.

Testing is often an afterthought in the planning process; installation sequences are always at the forefront of planning activity. By the time we begin to demarcate test boundaries and compile test packages, we are well into construction. This approach yields reactive testing approaches, often generating exponentially more tests than are actually required. This approach forces re-work, increases schedule durations, inflates costs, and increases loss management risks.

It’s a problem with an absolutely straightforward solution. Addressing the issue doesn’t require heavy technology investment, more personnel, or higher equipment expenditures. Reducing construction and testing costs can be achieved by simply building to test. A Build-to-Test planning program eliminates the double execution of flange activities. On large projects, this program can generate millions of dollars in savings when you consider the reduction in labor and material costs. The question is, why aren’t you building to test?

The Standard Practice

Figure 1 — Heat Exchanger Configuration

Figure one illustrates a 2-exchanger configuration with product and cooling water supply and return connections. The piping installation requires large bore torque flange management activities, multiple sets of studs, nuts and gaskets (sometimes double, depending on the specification). Installation is performed at 2 different elevations; some of these bolt-ups will be completed on scaffolding.

The typical bulk construction planning installation activity sequence would be to set the exchangers, then install all the piping either with figure 8 blinds or with spacers. All this work is normally completed during the same time period with the same personnel and equipment. Large bore connections on most projects are torqued with hydraulic wrenches, often operated by contract personnel and overseen by quality control. This is considered the normal or typical procedure for construction. Teams simply look to complete the installation of all available piping, nothing more.

During the completions phase of the project, we return to the same location with the same or a new group of personnel. The flanges are undone. The figure 8 blinds, which cannot be used for testing, are removed. The original gaskets are discarded and new gaskets are installed with test blinds during a second round of torqueing. Testing studs are required for use. With some specifications, the studs are one use only and must be discarded after the original torque or tension. In this instance, those previously installed would be discarded with the gaskets.

Keep in mind, we require heavy machinery to lift the hydraulic machines. Contractors are required to complete specialized torqueing activities; therefore, this process has us calling those same personnel back again to undo work we paid them to complete. Also, quality personnel are double inspecting these flange activities, performing an inspection at the time of initial torque, then again during testing.

Worse yet, after we complete our testing, we enter a third round of torqueing. We once again return to the same location with our personnel and equipment, discard the second set of gaskets, and in some cases the studs and nuts, and replace them with new, completing a third torque of the flange. Three times we torque the same flange with this standard process; it’s one time too many.

In this example we’ve added a round of large-bore torques for no purpose. We’ve destroyed many gaskets and at best case scenario triple-handled all the bolting; worse case we’ve wasted the initial bolts and are forced to replace them.

A major difference between bulk construction and completions/testing is the scope and schedule consideration. During the bulk phase, all work in the immediate area is captured. It makes the most sense to install test binds and materials at the time the piping components are originally installed. This is the most effective and efficient way to execute the work.

During completions and testing, the system/sub-system test is in focus. This difference in thinking forces us to revisit the same location time and again to work on individual components. As these tests are completed, they are often smaller than should be, and the work requires a higher resource draw due to the systems priority over bulk completion. This is the worst stage in the project to be planning test activities. By nature, the way they are executed will be more costly than they need be.

To overcome this challenge, we must change the way we approach test planning. We must recognize that tasks we complete during construction, if not aligned with test requirements, will require rework. Delineating test limits earlier in the project lifecycle, and building to test, reduces costs, reduces schedule durations, prevents material loss, and lowers project risks.

What is Build to Test?

Build-to-Test is the methodology of integrating system test planning into the detailed engineering phase of the project, and building test activities into bulk construction workflows. It’s a shift from standard, requiring design and construction teams to work collaboratively to define early test limits in effort to minimize the cost of test programs. Early implementation is key to program success; implemented too late, it becomes difficult to change existing work package sequences and content.

All test limits can be preliminarily defined when P&IDs are finalized. If advanced enough, design teams can actually include test blinds on isometric drawings as temporary materials, making it easy for construction teams to include Build-to-Test methodologies into their workflows. To do so requires the early involvement and support of engineering teams.

Test zones must be identified with blind locations and the test packages must be populated in virtual format, prior to the first piece of above ground pipe being installed. Every bolted connection completed during bulk construction must either be a final bolt-up or a test blind bolt-up. To do otherwise is to execute unnecessary work, extend schedule duration, increase cost by destroying material without cause, and add high risk man hours to the project.

What’s Needed to Implement This Program?

Management buy-in and support is key to the success of this program. Without it, teams often revert back to standard workflows. To implement a Build-to-Test program, the leadership team must mandate and support the program throughout the project lifecycle.

Regardless of when or how testing is planned, the project must onboard personnel to manage the process. Many project teams don’t consider this a priority or see the benefit of doing so until they’re well into the bulk construction phase. The fact is, to truly begin with the end in mind, the testing coordinator should be involved in the project as early as the 30% model review; this individual should have early engagement with quality control/inspection, turnover personnel, and facility owner operations personnel. They must also fully understand the system completion priorities and overall strategy.

Test limits should be defined in the virtual construction model. By visually identifying test limits in the model, teams can identify opportunities to join tests, maximize personnel and equipment usage, and eliminate redundant work. Digital planning tools provide teams with the opportunity to collaborate to improve construction planning and execution outcomes.

Teams must build test setup activities into the construction execution plan. Work packages should include test materials; construction teams must follow the test plan to the letter. Gone are the days of testing 1 or 2 spools to gain minute amounts of progress. Tests are optimized in all circumstances, thereby taking the guesswork and ad hoc approach out of the equation.

The Reality of It All

When industrial construction teams begin to reach the end of bulk construction activities and begin testing, they find themselves in a very different set of circumstances. It has often been said that anyone can build 90% of a project but have pity on the poor souls who must finish it. A Stanford professor summed it up best by saying the first 80% of industrial projects consume 80% of the budget, while the last 20% consumes the other 50%. The end of the project, when we should be coasting to the finish line, is typically when we realize that the misdemeanors we committed early on come with penalties fit for high-crimes.

By employing a Build-to-Test philosophy, we eliminate rework at a critical time in the project when resources are at a premium. Work crews and support staff, along with the equipment, shouldn’t be drawn away from the Path of Construction to handle ad hoc test requirements. This seemingly small innovation minimizes back and forth crew movements and area congestion that’s common at a time when projects are transitioning from greenfield to brownfield activities during start-up.

Summary

Digital solutions are empowering teams to constantly push the boundaries of traditional project delivery methods. Successful organizations are searching out and discovering new innovations and automations every day. Processes are becoming leaner and the bidding process is becoming more competitive. Maintaining a competitive edge in the digital age requires teams to rethink the processes that are assumed to be standard.

This article describes just one way that construction project teams can leverage 3D design and construction models to improve the way they build. Build-to-Test programs provide opportunities to drastically reduce the cost of testing, while shortening schedule durations and reducing high-risk labor hour activities. The cost of implementation is negligible; the savings are substantial, and quantifiable.

The fact is, we all like to use the catch phrases such as ‘begin with the end in mind’. But, too often teams don’t actually practice them. For construction project teams to bridge the gaps that continue to yield poor project outcomes, or for the scorpion to cross the river, we must change. Building-to-Test is a great place to start.