OPO: one person's opinion

Engineered Systems, March, 2001 by Lawrence Farrelly

Field-erect boilers can solve real problems, but the path to true success involves standards and accountability.

Early designers of buildings left us, generations later, with few choices for upgrading and/or replacing existing internal heating plants. Little thought was put into the challenges designers and installers would face when the original plant became obsolete. Some buildings have their boiler plants buried so deep in the bowels of a sub-basement, one may need to have physical training just to get there!

So what do we do? Being intuitive, problem solvers (and creators) by nature, we figure out a way to conquer this problem. The pencil hits the pad, and a component boiler is born. "Out-shop" or "field-assembled" boilers allow replacement without requiring the often prohibitive expense of structural modification, excavating, extensive rigging and associated state and local permits. With a field-erect boiler, the integrity of the building is not disturbed at all. The field-erect boiler is a positive alternative.

DISJOINTED PROCEDURE

Has this market evolved much? Maybe with different types of available designs, but the core component, the actual field assembly procedure, has little progress to show in the area of advanced accountability and safety.

Accountability, control, and safety have much in common. Accountability adds the solidifying layer of protection for the professional engineer and the ultimate enduser. Traditionally, mass producers of field-erected boilers, and the method of distribution used, provide little control over the total product from manufacturing plant to the boiler room. These boiler sections are mass produced, individually tested, and shipped in quantity to equipment wholesalers. At this point, product control is difficult to achieve at best.

The direct accountability link to the manufacturer is frayed. When a boiler order is placed at a wholesaler by an installer, these sections are pulled, not as complete traceable assemblies, but as individual pieces and shipped, often from different lots. This can lead to mismatching of component parts that are prepared by a warehouse employee who may not have the knowledge of the importance of matching production, serial, or registration numbers.

It is not uncommon for an ordered boiler to arrive at the point of delivery incomplete or missing several key components. It becomes the installer's responsibility to identify the missing parts and request order fulfillment. He must return to the wholesaler (who may or may not keep an entire stock of component pieces in-house), and when an aggravated installer who needs parts immediately is standing at the service counter, he is going to get them. The wholesaler may have to raid another material lot to satisfy his customer.

TIME FOR A CHANGE

Think about this cycle being repeated numerous times, year after year, and it is easy to see how unaccountable the "old" field-erect boiler industry really is. Aside from the obvious frustration to the installer, added time and altered scheduling affect the anticipated continuity of the whole assembly and installation plan. As a result, the end-user may have made a compromise he will never be aware of. Do the engineer and owner also know that as of this writing, many of these boiler assemblies, once completed in the field, are not required (unless by local code) to pass a field hydrostatic test witnessed by an authorized inspector?

A field-erect boiler should have the same quality control, material accountability, and consistency as a factory packaged boiler. For years, the industry accepted the "old" way because little attention was paid to improving the overall quality of this market.

Some field-erect methods do offer accountability by selling boilers as field erected, with the assembly performed only by factory employees. This is a practical method in an area where factory people can be dispatched daily. The method ensures the installer's inherent knowledge of each component piece and its proper place on the assembly.

Some safety standards, such as the Underwriters Laboratories (UL) listing, are usually required at a minimum for (packaged) boilers being installed in schools, public buildings and the like. Why does the specifying community insist on this listing? Because it is a recognized industry safety standard, and it is available. UL always had concern for the field-erect boiler; however, for no discernible reason, no manufacturer stepped up to the plate to help make an important industry change until recently.

ONE SOLUTION

The most current field-erect accountability technology comes from Underwriters Laboratories Safety Standard UL2096, Field Erected Boiler Assemblies. This standard ensures accountability from factory to finished product in the boiler room.

This standard follows the boiler and its respective components from order entry, to the shop floor, to the loading dock, to the final destination. Various tracking numbers and identification codes will differentiate each particular boiler and companion component so that on multiple field-erect boiler projects, it will be easy to properly match each individual component to its factory and code predetermined mate.