Boiler Blog | Nationwide Boiler Inc.

Nationwide Boiler is known as being an innovative leader in the rental boiler industry. Over fifty years ago we pioneered the mounting of a 24,000 lb/hr package watertube boiler to a highway-legal trailer, and followed with many other firsts including the world’s largest trailer-mounted saturated and superheated steam boilers (125,000 lb/hr and 110,000 lb/hr, respectively).

In this age of digital technology and pandemic isolation requirements, Nationwide Boiler’s control division, Pacific Combustion Engineering, realized the need for virtual factory acceptance testing (FAT). An FAT is an essential element of the testing and acceptance of new critical control systems. The main goal of this test is to prove and certify performance built for a specific application and ensure all design requirements are attained.

Pacific Combustion’s new test gear consists of a 19” HMI that replaces toggle switches, indicating lights, potentiometers, and analog gauges. A PLC drives relays and consists of contacts that can be configured for the voltage that is required for input simulation. Outputs are displayed via selectable 120vac and 24vdc terminals. Analog 4-20ma inputs are selectable as either loop or self-powered.

During the virtual FAT, a web portal is accessible by the client through an audio/video link to the testing, and the client can actually operate the test rig HMI screen from their location. Links are also furnished to the burner management / combustion control system PLC and HMI.

This is a truly unique innovation at a time where travel can be difficult, providing an alternative to the traditional FAT and allowing business to continue even in heightened times like a global pandemic.

For more details on our virtual FATs, be sure to check out our upcoming feature in Process Heating Magazine. We will post the direct link as soon as it's available. And be sure to give Pacific Combustion Engineering a call to assist with your next control system upgrade. 360-335-1443

It's that time of year again for our annual freeze protection reminders. As you know, winter can bring extremely cold weather conditions, especially in Canada, the Northeast, Midwest, and Upper Midwest. To reiterate what we have been saying for years, here are a few things to consider to protect your rental boiler and auxiliary equipment (deaerators, water softeners, etc.) from damage due to freezing temperatures this winter.

1. If you are renting a trailer or skid-mounted firetube or watertube boiler and installing the unit outdoors, these systems are completely exposed to the environment. User's should consider enclosing the front and/or the rear end of the boiler, or build a temporary enclosure around the entire system. An external heating source should also be used. 

2. Install the proper heat tracing (steam or electric) and insulation on all main lines and piping components, regardless of whether the boiler (or auxiliary equipment) is in operation or sitting as stand-by. This should include the following lines: 
      - Sensing lines for all transmitters
      - Primary and auxiliary low-water cut-offs
      - Water column and connected piping
      - Bottom blowdown and surface blow-off piping, depending on the length of the piping runs. These valves should also be left open. 

With over 30 years of experience, our General Manager at Pacific Combustion Engineering, Jack Valentine, is an expert when it comes to the design of combustion control systems. In the Winter 2021 edition of Today’s Boiler, Jack discusses the features and options typical of Combustion Control Systems today. Let’s take a peek at what he had to say.

Combustion equipment safety is essential for the daily operation of facilities and safety of plant personnel. Safety protocols and mechanisms in industrial plants have improved drastically in the last century, but incidents still occur far too frequently. Because boiler systems are inherently dangerous, safety must be factored into the design of not just the boiler, but also the burner, combustion control, and the overall operation of the system.  

The Combustion Control System (CCS) on a boiler, also known as the Boiler Control System (BCS), refers to the set of instrumentation and controls that modulates the firing rate of the burner in response to load demand while maintaining the proper air/fuel ratio (AFR). It works in conjunction with the Burner Management System (BMS) that provides safeguards before, during the initial light-off of the burner, and at shutdown. The BMS also provides the flame safeties and interlocks required to keep the boiler safe during continuous operation. Depending upon the complexity of the boiler, the CCS can also provide other functions such as drum level control and draft control.  With Low NOx burners, it also controls the proper amount of flue gas recirculation (FGR) to the burner.

For the sake of simplicity, the various types of CCS described below will be for boilers firing a single fuel gas only; fuel oil and solid fuel systems add an entirely new level of complexity.

Tomato season is here, and we already have a 70,000 lb/hr, 400 psi design trailer-mounted rental boiler on location at one of our customer sites to support peak season steam demand. This boiler is rented annually in the Central Valley of California for three to four months during the tomato processor’s short but critical production season. To meet the requirement of 5 ppm NOx, the boiler is supplied with an ultra-low NOx CataStak SCR System. This solution allows the facility to operate their own boilers without overworking them, while complying with local air regulations and satisfying seasonal demand.

Some years ago, the company identified a bottleneck in its evaporation system that hindered peak production capacities. The bottleneck was easily resolved; however, it would take more steam to fully realize the increase in production. Although the existing boilers were capable of running the newly found evaporation capacity, the increased production required the existing boilers to operate at 100% output continuously, leaving no room for margin and no buffer against any process anomalies. After evaluating the cost of investing in a new boiler, the detrimental effects of operating the existing boilers at 100 percent output, and the process vulnerabilities of having no excess steam capacity, the decision was made to rent a supplementary steam boiler on an annual basis.  

Many industries face periods of increased process steam requirements and to satisfy demand, steam can be supplemented with a temporary rental boiler. This practical solution allows facilities to maximize the resources needed to meet current, short-term and long-term steam needs. A short-term or long-term rental solution can save time, conserve capital, minimize risk and maximize available resources.

Check out our past article from Today’s Boiler Magazine to learn more about how temporary boilers can support seasonal steam demand, and contact us today if a rental boiler may be the solution to your peak season needs!