Quality Blog

Project Blog Introduction

EPR’s project management, restructuring, and consulting experience is highly varied, often very technical, but always deeply immersive.  These formative experiences, on top of our traditional project management expertise, have resulted in a unique industry perspective.  

Poorly managed construction may exhibit problems such as safety, schedule, and escalated cost.  However, plant quality is the most significant determinant of the forward asset (plant) value.

This blog is not intended to be a deep technical reference but rather a discussion-level view.  However, our intention is to bring a real-world perspective of how construction quality impacts an owner, with enough technical content to provide context.  It is assumed the more technical reader will understand the basis for these observations.

Additionally, some posts deal with ‘case studies’ of projects EPR evaluated where poorly conceived execution strategy prior to mobilization created enormous realized construction risk and soured the asset with enduring bad quality.  EPR believes a poor execution strategy places an owner’s team at a severe disadvantage often preventing plant delivery commensurate with the contractor agreement.

All the problems identified in this blog could have easily been avoided with skilled proactive oversight at minimal or no incremental cost.  If your project is near COD or early in construction and exhibiting some of these (or other) concerns, EPR can help.

To discuss your project needs, please contact EPR

Safety Gates
Safety
August 09, 2018

Sometimes good sense isn’t that common.

This is particularly true when it comes to safety gates at the top of access ladders.  Contractors in developing regions often have a view that labor is so inexpensive, that making things is cheaper than buying items, especially if sourcing from outside the country.

Unfortunately, this ‘handmade’ product is just not of a suitable quality and the hardware provided for spring closures is equally bad.  Keep in mind while viewing the photos, that companies make excellent bolt on plastic arms that last a very long time, work without fail, and are easy to install.

The importance of these items cannot be overstated and where they are absent or not working, an operator can be subjected to a nasty fall that could easily be fatal.  OSHA is clear that this is not a small matter, thus the CFR 1910.23 standards that govern installation and use of such devices.

While seemingly minor, for owners that are in the process of developing specifications to attach EPC contracts, it is suggested that you pick a nice quality swing gate and allow the contractor... Read more

Contractor Savings

None.  Probably cost more to fabricate a gate.

Repair Costs

This issue is not about cost but prevention of injury and fatalities.  Both can have a high financial and moral cost.

Pipe Rack Bolting
Safety, Structural Steel
May 21, 2018

The consequence of structural failure in a power plant is operationally serious and can be life threatening.
 
When structures are designed for bolted connections usually "high-strength" fasteners are indicated (ASTM A325/A490).  If these bolts are not installed properly, per the standard (AISC/RCSC, or other), the joint does not support the loads expected by the engineer.  So, when loose bolts are observed in completed facilities, it is alarming because it is an indicator the contractor's bolting program was flawed.  Properly installed bolts are verified to be pre-tensioned, which practically eliminates nuts backing off for any reason.

So what constitutes proper pre-tensioning?  The code guidelines are specific, however, in simple terms bolts must achieve a certain amount of stretch.  The complicating factor is that pre-tensioning varies depending on manufacturing lot, and environmental conditions like moisture because of variable thread friction.  This means that daily testing (for each lot) is required to determine a "torque value" for the assembly.  If this is not... Read more

Contractor Savings

Little or none.

Repair Costs

Contractor: RCSC arbitration is moderately expensive.  Owner: Risks structural failure and personnel injury.

Lightning Protection
Electrical, Safety
May 11, 2018

On many projects, lightning protection is installed by a subcontractor and happens near the end of a project when other activities dominate everyone’s attention.

As a system, lightning protection requires attention to details, so it is not surprising that on projects that generally suffer from workmanship problems, the lightning protection installations also suffer.  This is unfortunate, because the standards are in place to provide guidance for protection from strikes that can have severe consequences to plant equipment and personnel.

For those familiar with Houston, TX, it can be easy to understand the amount of lightning present is significant.  The new plants used in these examples are also in a similar flash density (flashes/mi2/yr).  This is to suggest, this is important.

The EPC contract was clear in these cases regarding the requirements.  The photos show workmanship defects that are representative of systematic failures throughout the systems.  This included grounding conductor connections not being properly crimped and often disconnected, material incompatibility with... Read more

Contractor Savings

None.

Repair Costs

Repairing a bad installation is not largely expensive, however, significant cost can occur for an Owner if a lightning strike occurs without a functional protection system.

Not-so Structural
Safety, Structural Steel
May 09, 2018

Strangely, at several plants we have reviewed there seems to be at least a few occurrences of structural steel near steam turbines being gouged out by flame-cutting to fit piping or other equipment.

The reason is obvious.  It takes no effort to cut a beam compared with the proper approach to ask engineering for a modification.

However, people walk and work on those platforms including often disassembling valves or other items that weigh a bit.  Some of the photos show a platform that is failing (sagging) under its own weight.

Overall, not a great present for a contractor to leave an O&M team.

One high-level observation…  On projects with an involved and demanding owner, the type of behavior it takes to affect these types of actions is usually not found.  Why?  Because it is implicitly understood there is personal risk (being fired) for an individual involved in this type of careless activity.

Contractor Savings

Minimal cost but takes some engineering involvement.

Repair Costs

Can be a minor expense to repair, but more important as a safety issue.

Coatings Delamination
Coatings, Structural Steel
December 19, 2017

EPC Contract indicated “the project site is subjected to moist and heavily polluted salt laden air”…

While the contractor took precautions to properly specify the coating systems, the surface prep and coatings application was flawed anyway. Normally, an effective shop (or field) inspection program will catch the problem early and be resolved in favor an effective coating process. In this facility, there was extensive evidence that either no QC program existed, or the inspector(s) were compromised.

After 18 months in operation, the coatings appear 15 years old. To varying degrees, most of the structural steel coating systems in the subject plant are in a progressive state of failure with the substrates rapidly and increasingly unprotected. 

It was determined much of the steel coatings suffer from varying failure mechanisms.  However, this photo is an example of improper surface prep (NACE/SSPC) and inconsistent dry film thickness, often with a top-coat greatly exceeding manufacturers requirements.

Contractor Savings

Minimal to no cost savings. Some time may have been saved if rework in the shops had been required.

Repair Costs

Owner: Coating system will need an aggressive repair program as opposed to the anticipated touch-ups. Magnitude large but unknown.

General Welding
HRSG, Structural Steel, Welding
December 10, 2017

In a completed facility inspected by EPR, there was a noticeable level of unacceptable general welding.  As a frame of reference, this plant was purchased to be built by an experienced contractor to western standards (AWS) in a location where suitable labor was available.

During the initial stages of the review, it became clear that some workmanship lapses were so pervasive that a plant-wide cataloging of the defects was impractical.  Therefore, a detailed review was conducted on one power train to determine a representative condition of the whole plant related to general welding.  

171 welds on pipe supports, electrical cable tray/conduit supports, and gallery steel were evaluated per the visual acceptance criteria standards of AWS D1.1, Sections 5 and 6.  20 (twenty) were found to meet the most basic “stand-back” visual acceptance criteria of the AWS D1.1.  Effectively, at least 89% of the welds did not meet the AWS visual acceptance criteria, and many (most) failed with multiple defects.  Keep in mind this investigation did not get into real detail with the use of Cambridge or fillet... Read more

Contractor Savings

Clearly some money was saved, but it could not have been significant.

Repair Costs

Owner:  Could be as little as occasional maintenance labor for failed items, or significant when important failures occur costing operating hours/days.

HRSG Bolting
HRSG, Safety, Structural Steel
December 06, 2017

Large (HRSG) equipment erection is about attention to detail, but not overly complex. However, the structural and thermally cyclical nature of these units demands that proper methods and OEM instructions be observed.

In this case, a large new plant with 12 units was inspected one year after COD by EPR. There were so many deficiencies it is clear proper procedures were not followed. For high-strength bolting (ASTM A325/A490) proper pre-tension testing must occur, in addition to proper substrate alignment, thread engagement, and other details. The pertinent requirements, in addition to being code stipulated, were cascaded with clarity in the Contractor’s own specs and procedures, so they should have been followed and QC verified.

For both slip-critical and direct-tension applications bolting was observed to be missing, loose, installed in flame-cut holes, loose plies, and a variety of concerning problems. Over time, this condition will worsen and result in two safety concerns; falling fasteners, and unsafe structures.

Contractor Savings

Minimal.  It takes no more time to pretention bolting by the iron worker.  Further, QC checks should have been performed.

Repair Costs

Owner: Safety and outage concern. Repairs need to be affected.  EPCC: ~$25,000 per unit for equipment, new bolting, and man-lifts.

Not-So-Structural Grating
Safety, Structural Steel
September 20, 2017

After noticing an unusual number of severe workmanship issues with grating penetrations, a study was conducted on one portion of a recently visited facility (one power block).

In the subject area, 231 penetrations through grating or deck plate did not conform to the requirements of contractor’s own Structural Erection Procedure, which states that all cuts of 3 grating bearing-bars shall be banded, and further, that field-cut openings shall clear insulation by 1”.  The contractor’s own structural drawings also indicate a requirement/detail showing the penetrations of grating and checker plate reinforced with toe plate and banding.

Of the 231 inspections, 39 were missing banding, 174 had no toe plate, 10 did not meet the required insulation clearance, and 8 open holes were left in the grating.  In total, roughly 100% of the penetrations were out of compliance with normal practice and the contractor’s criteria indicated above.

More concerning, is that the workmanship is so poor in some instances that almost none of the bearing-bars remain intact leaving the structural integrity of the... Read more

Contractor Savings

Labor/Supervision savings and probably some material.

Repair Costs

Contractor:  Some material expense and labor.  Scaffold in some locations perhaps.  Owner: Risks injuring O&M personnel or worse.

Steam Vents at Platform
Engineering, Piping, Safety
September 19, 2017

EPR observed that steam safety valves had lifted at some period in the past during a load transient. The energy from an un-silenced steam release at 1,000F is violent and typically includes a powerful supersonic noise wave. Debris remains impaled on nearby structural steel and equipment from the force of the previous steam discharge.

A serious safety concern is that a personnel access platform is above and adjacent to the five (5) vent stacks. If any personnel would have been located on the platform during a release, they would have no doubt been seriously injured and burned. The owner's operators are exposed to a serious risk until this condition is resolved.

This safety problem persists because of a failure of engineering, piping construction, and the contractors commissioning team to resolve the issue prior to COD.

This is a very dangerous design and all 5 relief valve vents need to be extended above the structure or vented away from the access area.

Contractor Savings

Minimal cost to extend the vent stacks to a safe elevation.

Repair Costs

Owner: Potential O&M personnel injury or fatality with associated costs. Contractor: Minimal cost to extend the vent stacks to a safe elevation.

Weld Slugs
Structural Steel, Welding
September 07, 2017

Proper power plant construction is typically based on layers of processes and checks.  Often observed quality problems are concerning due to their possible systematic nature and origin as a supervision problem.

In the realm of field welding, few defects speak as clearly about poor contractor quality and a loss of accountability than a slugged weld.  The attached photo reveals that a piece of “all-thread” rod was used to fill several weld passes.  Even worse, the welder didn’t even feel compelled to bury the slug under the cap and so it remained exposed.  This indicates a site ethic existed, where the welder felt there was no consequence to being caught, or perhaps the welder was confident that no one would verify his work.

There may be several codes or standards that cover this type of activity, but it violates the general welding standards of AWS.  The practical reason “slugs” are not acceptable is due to the uncontrolled and usually low-grade nature of the material used as “slugs”.  This implies a possible structural deficiency, which is of course not acceptable.

In this facility,... Read more

Contractor Savings

The joints need welding, to do it wrong saves no time.  Unqualified labor may be marginally cheaper, but not if the work is rejected!

Repair Costs

Contractor: Cost of repair is small; but brand damage is meaningful.  Owner:  Structural failure risk increases, but small. Concerning indicator of plant quality!

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