Preventing Equipment Failures

Preventing Equipment Failures
Boilers Electrical Distribution Systems Air Conditioning Equipment Have this slide up on the screen before attendees arrive. Once all are there, or the published start time has come, open the workshop by introducing yourself and thanking the customer for allowing HSB the opportunity to present this workshop.

Any Questions? Then let’s get started!
Are there any questions before we begin? Take time to answer any that are asked. If not, or after having answered all questions, then let’s get started! The Hartford Steam Boiler Inspection and Insurance Company

Preventing Equipment Failures
Each year many millions of dollars in property are damaged, thousands suffer serious injuries and, worse of all many lives are lost due to the failure of improper operation or maintenance of boilers and electrical and air conditioning equipment. The question you need to ask yourself is simply this, do you want to be part of these statistics? The Hartford Steam Boiler Inspection and Insurance Company

Boiler Maintenance We’ll start off our discussions today by taking a look at the basic maintenance requirements for boilers. Before we begin our discussions on boiler maintenance let’s start off by defining what we mean by the term “boiler”. The Hartford Steam Boiler Inspection and Insurance Company

What is a boiler? A closed vessel in which water is heated, steam is generated, or steam is superheated for use external to itself by the application of heat. Ask attendees, give me some characteristics of a boiler, use their responses to build up to the description in the slide. While this is a good description, it is very general in nature. We could apply this description to either a hot water heater or a nuclear reactor, however we would not refer to either of these as boilers. So, we need a more definitive statement to describe a boiler. The Hartford Steam Boiler Inspection and Insurance Company

Boiler Categories Power Boiler High Temperature Hot Water Boiler
Heating Boiler Here the American Society of Mechanical Engineers Boiler and Pressure Vessel Code helps us out. The ASME Boiler and Pressure Vessel Code defines boilers based on their rated pressure. Boilers are broken down into three basic categories, (click for first bullet) Power Boiler, (click for next bullet) High Temperature Hot Water Boiler,(click for final bullet) and Heating Boiler. We will only be discussing Power Boilers today. The Hartford Steam Boiler Inspection and Insurance Company

Watertube Boilers Components: Steam drum Water (mud) drum Tubes
In this cutaway illustration we can see how a typical water tube boiler is built and some of the major components. Review each term and explain what it is. The Hartford Steam Boiler Inspection and Insurance Company

Watertube Boilers C-B Model 4 Watertube boiler While the majority of Watertube boilers are designed for industrial steam supply, there are some styles that are used for commercial or institutional steam systems. The Hartford Steam Boiler Inspection and Insurance Company

Firetube Boilers The other type of boiler commonly used for both high and low pressure steam is the firetube boiler. Firetube boilers are characterized by the transfer of heat from inside the boiler tubes to water surrounding the tubes. Firetube boilers are most widely used in small to medium industrial settings where there is a moderate steam load demand and load swings occur gradually and infrequently. Firetube boilers are the oldest type of boiler. While there are several variations in design the most common style of this boiler is the Firetube Scotch Marine. Originally designed for use in marine applications for propulsion, they were quickly adapted to stationary use and have become the backbone of industrial steam boilers. Firetube boilers are easy to operate and maintain. Their design allows for easy access to both the water side and fire side areas for cleaning, inspection and repair. Repairs tend to be easy to perform and very cost effective. Relatively inexpensive to construct, they are generally very cost effective to install. Their simple design makes them very fuel efficient as well. Firetube boilers are generally rated in boiler horsepower and range from as small as 25 hp to as high as 1,000 hp. The most common size found is between 150 hp to 500 hp. Proper operation and maintenance are essential to the reliability and efficiency of these boilers. While their simple design makes them very forgiving of poor maintenance, their relatively compact size makes them very susceptible to damage from control and safety device failures. The Hartford Steam Boiler Inspection and Insurance Company

Firetube Boilers Components: Shell (Drum) Tube Sheets, Front & Rear
Tubes (Flues) Furnace Stays (Stay Bolts) This illustration shows a cutaway of a typical firetube scotch marine boiler. Review each major component of the boiler as shown in the illustration. Explain how combustion gases travel through the gas passes of the boiler. Stack in rear, 1 or three passes, stack in front, two or four passes. The Hartford Steam Boiler Inspection and Insurance Company

Firetube Scotch Marine
In this photograph we see a typical Firetube Scotch Marine Boiler. Point out the various controls and safety devices visible on this boiler. Point out the improperly installed LWCO on the side of the boiler. Explain that the boiler was originally installed with only one LWCO while the local jurisdiction requires two. A second, electronic type, LWCO was added at the only convenient location, however, this is well below the lowest permissible water level so it provides no protection. Also note the drain valve for the float type low water fuel cut out device has no piping to direct it to a safe point of discharge. This creates a personnel safety hazard. The Hartford Steam Boiler Inspection and Insurance Company

What could possibly go wrong with my boiler?
Let’s take a look at some typical boiler failures! Now that we have gained a familiarity with some of the boiler types normally found in commercial and industrail use today let’s take a look at what can go wrong with a boiler. Each year, there are several deaths and injuries as well as hundreds of thousands of dollars in property damage and lost productivity resulting from boiler failures. Failures that could have been prevented. The underlying purpose of this workshop is to help you better understand how the basics of proper boiler maintenance can help prevent these costly failures. We only need to look at the National Board of Boiler and Pressure Vessel Inspectors statistics to understand the size of the problem. Although very dependable, boilers still must be operated and maintained properly! So, what can go wrong with my boiler? Let’s take a look at the more typical boiler failures.

Major Causes of Boiler Failures
Low Water Poor Maintenance Failure of Controls and Safety Devices While there are many reasons why boilers fail, the three most common are: Low water – discuss what low water is, how it happens, and why it happens. Emphasize LWCO as major protective device and that we will look at these in greater detail. Poor Maintenance - Discuss what is meant by poor maintenance, fireside, waterside, corrosion, scale, etc… Failure of Controls and Safety Devices – Discuss how the failure, or lack, of necessary controls and safety devices can lead to boiler failure, eg, low water, overpressure, improper fuel combustion. By focusing our maintenance on these three areas, we can significantly reduce the possibility of a boiler failure, as well as improve boiler safety, reliability, and efficiency. The Hartford Steam Boiler Inspection and Insurance Company

Low Water Results in over temperature condition
Can cause extensive damage to boiler Or Catastrophic failure of the boiler Low water is a condition that results when one of two things occur; the boiler requires water but fails to call for it, or the boiler calls for water but fails to receive it. These conditions are usually the result of some malfunction in either a control circuit or a mechanical component. Low water itself is usually not a problem because the boiler is equipped with protective devices designed to detect a low water condition and shut down the boiler before damage can result. However, should these safety devices fail, or are not properly installed, or are non-functioning, the results can be catastrophic. The Hartford Steam Boiler Inspection and Insurance Company

The Hartford Steam Boiler Inspection and Insurance Company
Here we see a Firetube Scotch Marine Boiler that has suffered a low water event. As you can see, the furnace tube has deformed and collapsed onto itself, tearing away from the attachment weld at the tube sheet. There are a couple of clues that tell us that, in all likelihood, most if not all water had boiled away from the boiler before the pressure vessel was breached. The most significant of these is the fact that the boiler is still in the boiler room. If there had been a significant amount of water remaining in the boiler when the pressure vessel was breached we might have seen quite a different result. NEXT SLIDE The Hartford Steam Boiler Inspection and Insurance Company

Low water can be an extremely serious event that can result in extensive damage and quite possibly personal injuries or even loss of life. This photo shows a boiler that has suffered low water. Why do you think the boiler in the previous photo simply tore open and this boiler launched itself through the boiler room wall? The boiler failed while there was still water under pressure inside. Once the boiler failed the pressure inside instantly dropped to atmospheric pressure. The water inside, which remained at the elevated temperature necessary for boiling under pressure, then flashed to steam, increasing its volume 1600 times. The result was launching the boiler through the wall of the boiler room. A recent boiler failure in a commercial laundry facility reveled that when the boiler failed the rear door took off in one direction at 90 mph and landed 300 feet away, while the boiler went in the opposite direction at 30 mph and crashed through a cement block wall. Protecting your boiler from low water is one of the most important aspects of a boiler maintenance program. Protecting against low water involves proper maintenance of boiler water side conditions, fire side conditions, combustion controls, and safety devices. Remember, a boiler is a system and must be maintained as a system. The Hartford Steam Boiler Inspection and Insurance Company

Damage from over temperature can result from causes other then low water. Here we see a Firetube boiler that has suffered damage from overheating caused by the accumulation of scale restricting heat transfer. This causes the metal to overheat and fail. While the damage from such a condition may not be as catastrophic as that resulting from a low water condition, the damage can be extensive and very costly and time consuming to repair. Scale like this can be prevented through a properly developed and implemented boiler water treatment program. The Hartford Steam Boiler Inspection and Insurance Company

Poor Maintenance Now, let’s take a look at some of the poor maintenance practices we see that can lead to boiler failure. The Hartford Steam Boiler Inspection and Insurance Company

External corrosion resulting from a leaking drain plug. This damage can lead to a failure of the boiler when the metal becomes too thin to contain the pressure inside the boiler. This damage will result in an enormous cost to repair, as well as down time during the repairs. First, the boiler insulation jacket will need to be removed. In this case the jacket is made from a material containing asbestos and so will have to be removed by a contractor specializing in asbestos removal. A very costly job. Next, the damaged area will have to cut out to good metal and a new part fabricated. This must be done by an authorized boiler repair firm. After the repair has been made, the boiler will need to be reinsulated. Altogether, a basic maintenance task, fixing the initial leak, has become a major repair job that will easily run over into thousands of dollars. The Hartford Steam Boiler Inspection and Insurance Company

This photo shows the fuel train on a boiler where the boiler room has been flooded, repeatedly. The automatic gas valves are covered with residue, their protective covers are missing, there are several exposed electrical conductors, a transformer is hanging from the electrical conductors, there is evidence of leakage from under the insulating jacket, and the drain from the LWCO opens on top of one of the automatic gas valves. Ask attendees what they see wrong in this photo. Lead them through discovering each of the problems noted above. Ask what is the first thing that needs to be done (identify the source of the flooding and correct). This shows the need to extend the concept of maintenance to the entire system, including the equipment environment. The Hartford Steam Boiler Inspection and Insurance Company

This photo shows a typical steam cooker that has had a hand hole opening replaced improperly. As well as proper preventive maintenance, proper repairs are equally important. Again, emphasize the need to use only authorized repair firms. The Hartford Steam Boiler Inspection and Insurance Company

Failure of Controls and Safety Devices
Finally, let’s see how failures of boiler controls and safety devices lead to boiler failures. The Hartford Steam Boiler Inspection and Insurance Company

Improper maintenance can result in safety devices becoming non-functioning. This relief valve has become blocked with scale accumulations, it will provide no protection against over pressure. Here, again, what began as a small leak in the valve became an inoperative valve. The Hartford Steam Boiler Inspection and Insurance Company

A relief valve that has had the outlet nozzle capped off. The Hartford Steam Boiler Inspection and Insurance Company

A low water fuel cutout device from a hot water heating boiler showing the results of inadequate maintenance. Sludge can form quickly preventing the device from working when needed. The Hartford Steam Boiler Inspection and Insurance Company

In this photo we see inside the electrical connections for a low water fuel cutout device. Heavy corrosion from leakage between the steam/water side and the electrical box results in damage to the device that can leave it inoperable. The Hartford Steam Boiler Inspection and Insurance Company

The controller on this boiler, at right, is in an advanced state of deterioration making it unreliable. Ensuring that controls and safety devices are protected from corrosion or physical damage is an essential part of boiler maintenance. The Hartford Steam Boiler Inspection and Insurance Company

Earlier we noted a boiler where a second low water fuel cut out device had been improperly added to a boiler. Here, again, is another example of this problem. This type of low water fuel cut out works by placing a conductivity probe directly in the boiler so that when the water level drops below the probe, the boiler will shut down. In this case, the first problem we see is that the probe is not installed directly in the boiler but rather through a series of pipe fittings. Second, the device is placed below the lowest permissible water level. The device has been placed at the lower connection of the water level sight glass. The bottom of the sight glass is the lowest permissible water level. The low water cut out should be placed to shut down the boiler before the water level reaches this point. This arrangement also does not permit opening the piping for cleaning. Connecting piping for low water cut outs should have tee fittings installed to allow for cleaning. Finally, the pipe fittings used are galvanized steel, a material not allowed for use on high pressure steam boilers. The Hartford Steam Boiler Inspection and Insurance Company

This pressure limit switch has been disabled by placing a cardboard wedge under the mercury switch. This was probably done as part of a test of other boiler safety devices but was not returned to proper operating condition when done. Whenever a control or safety device has been disabled or by-passed to permit testing extreme care must be exercised to make sure that all controls and safety devices have been returned to operation and will function properly. Whenever controls or safety devices are by-passed for testing it should be done electrically, not mechanically. Mechanically disabling the control or safety device can result in damage to the device. If your maintenance program includes by-passing or disabling controls or safety devices for testing a written procedure should be developed and followed each time it is done. The Hartford Steam Boiler Inspection and Insurance Company

Preventing Boiler Failures
Proper Operation Proper Maintenance It’s all up to you! So, how do we prevent these failures? By paying attention to: The fundamentals of proper boiler operation – Proper maintenance and proper operation go hand in hand. The fundamentals of proper boiler maintenance – Proper maintenance practices must be followed in order to ensure the long term reliable operation of the boiler. It all depends upon you - You are the key to preventing boiler failures. Unless you are willing to follow proper operating and maintenance practices boiler failures are inevitable. Let’s review the basics of boiler operation and maintenance. As you will see, the two are inseparable. You cannot operate a boiler without properly maintaining it, neither can you maintain a boiler without properly operating it. The Hartford Steam Boiler Inspection and Insurance Company

Boiler Operation Prepare the boiler for operation Starting the boiler
Regular operation Controls and safety valves Feedwater treatment Let’s begin with boiler operation. Proper operation of a steam boiler begins by properly preparing the boiler for startup. Once the boiler has been prepared following proper startup procedures will ensure a safe startup without causing damage to the boiler. Emphasize the need for proper warm up and not over firing during startup. Once the boiler has been placed into operation you need to ensure that all controls are operating properly and the boiler is safe to remain in automatic operation. It is during routine operation that many of the required test and maintenance activities take place. An important maintenance item is the proper treatment of boiler feedwater. Scale can result in extreme loss of efficiency and ultimately damage to the boiler from overheating. Discuss proper feedwater treatment, emphasize the need to monitor the amount of makeup water being added to the boiler as this impacts the boiler treatment program. Test safeties with 75% of operating pressure on the boiler. Orient the red stripe on the gage glass so the operator can see it from the “usual” place. Make sure chains on safety valves do not exert pressure on the valve. The Hartford Steam Boiler Inspection and Insurance Company

Boiler Logs Why use them What to include How to use them
A fundamental, and often overlooked, part of an effective boiler maintenance program involves continuous monitoring of the boiler’s operating condition. By paying attention to how the boiler is performing, its operating parameters, you can develop information that will help you improve operational reliability, overall operating efficiency, and increase operational safety. Boiler operating logs are the key component to continuous monitoring of boiler operating conditions. By recording and tracking boiler operating conditions you can develop trends on how the boiler performs during various load situations and during different seasons. Many times, the information gathered will alert you to developing problems that, left unattended, will result in extensive damage, unplanned outages, and costly repairs. What data should you collect, and how is this used? Review sample boiler log forms in Appendix. Pressures Temperatures Operational testing of controls and safety devices Water treatment Boiler monitoring systems and data logging vs. the boiler log requirement Note that some jurisdictions require the use of boiler logs. The Hartford Steam Boiler Inspection and Insurance Company

Boiler Codes ASME Boiler & Pressure Vessel Code
ASME Controls and Safety Devices National Board Inspection Code Jurisdictional Rules Before we take a closer look at boiler maintenance, let’s first take a brief look at the codes that are followed to fabricate boilers and pressure vessels. While it is not necessary for you to know the content of these codes, it is helpful to know about them and how they affect boiler operation and maintenance. TP: Do not spend too much time with this. Emphasis should be on the areas of the jurisdictional rules that impact the trainees are maintenance/operating personnel The first code we’ll look at is the American Society of Mechanical Engineers Boiler and Pressure Vessel Code. This code consists of over 13 sections, covering everything from air tanks to nuclear reactor containment vessels. We are only concerned here with Section I, Rules for the construction of Power Boilers. This section of the code provide the rules that tell a manufacturer how to properly construct a power boiler to ensure that it will be safe to operate at the design temperature and pressure for that boiler. Part of what we do in boiler maintenance is to maintain the code integrity of the boiler, that is, make sure it stays in compliance with the code to which it was constructed. The next code we encounter is another ASME code, CSD-1, Controls and Safety Devices for Automatically Fired Boilers. This code provides the rules that provide for the proper controls and safety devices for a particular boiler. Many jurisdictions require all boilers to be in compliance with this code. This code cover boilers with a burner rating of below 12.5 million Btu/hr. Next, is the National Board of Boiler and Pressure Vessel Inspectors National Board Inspection Code, or NBIC. This code provides rules for the inspection and repair of boilers. This code is used by many jurisdictions as the rules governing the inspection and repair of boilers within their jurisdictional control or serve as a foundation for their specific rules. Finally, and of the most concern ton you as boiler maintenance personnel, are the rules governing boilers and pressure vessels for your particular jurisdiction. The Hartford Steam Boiler Inspection and Insurance Company

Jurisdictional Rules Inspection Frequencies Inspection types
Installation requirements Rules for repair Review the specifics of the local jurisdictional rules for each of the items in this list; Inspection frequencies – how often are inspections required, power boilers, heating boilers. Inspection types – internal or external Installation requirements – do the rules address installation, if so, review these rules Rules for repair – review the rules for the repair of boilers, who can do repairs, who must approve repairs, who must inspect repairs, etc… Add any applicable information from the local rules. The Hartford Steam Boiler Inspection and Insurance Company

Housekeeping Safety Fire Prevention Combustibles
paint, oil, gas and cleaning products Flammables wood, paper and cardboard keep at least 8 to 10 feet from the boiler Emergency Access Often overlooked, housekeeping is as important as any other aspect of boiler maintenance. Proper housekeeping helps improve safety by making the boiler room a safer place to work. Eliminating slip, trip and fall hazards, providing proper lighting and ventilation will all help make it possible for you to work more safely. Proper housekeeping practices may also help in preventing fires that may result from a boiler malfunction. Keeping flammable and combustible materials such as paint, gasoline, oil, and cleaning products out of the boiler room is a must. Often, however, existing conditions will not allow the boiler room to be cleared of all flammable and combustible materials. In such cases these items should be kept at least 10 feet from the boiler. Remember, the boiler room is not to be used for storage. Keeping the boiler room clean and free of clutter will allow full access during emergencies. In addition, local codes may have specific requirements for boiler room access. The Hartford Steam Boiler Inspection and Insurance Company

Controls & Safety Devices
Maintain control over boiler operation Monitor operating conditions Protect boiler from failure Controls and safety devices are installed on boilers to allow operating personnel to monitor and control the operation of the boiler and to provide protection from conditions that could result in failure. In order to make sure these devices are doing their job it is necessary to periodically test, inspect and service them. The Hartford Steam Boiler Inspection and Insurance Company

Controls and Safety Devices
Controls and safety devices are installed on boilers to monitor, indicate, regulate, or control: Pressure Temperature Water Level Combustion Auxiliary Equipment Pressure – Steam boilers are operated to produce steam at desired pressures. Pressure gages are installed to allow operators to monitor the pressure present on the boiler The gage serves as an indicator of that pressure. Maintaining the pressure gage in an operable and accurate condition is essential to safe operation. Temperature – Hot water boilers produce hot water at a desired temperature. As with steam boilers, properly operating and accurate temperature indicators will allow operators to determine if the controls are functioning and the boiler is within desired and safe parameters. Water Level – The single most important function of boiler operation is to maintain proper water level. Water level sight glasses are installed on steam boilers to allow operators to monitor the water level. These indicating devices must be routinely maintained in order to ensure the accuracy of the sight glass. Low Water Cut Off devices are installed on all boilers to protect the boiler from this most dangerous condition. Again, regular testing and maintenance is essential to their reliable operation. Combustion – Controlling the combustion of fuel is at the heart of operating a boiler. Regulating fuel combustion is used to maintain pressure or temperature at desired levels. Interrupting combustion when indicating and monitoring devices detect combustion failure or pressure or water level conditions are outside acceptable parameters is a function of the combustion controls and safety devices. Most of the safety devices installed on boilers are designed to interrupt combustion when adverse conditions are detected. Auxiliary Equipment – Boiler controls are used to operate the various auxiliary equipment used to support boiler operation. Fuel pumps, water pumps, air blowers, all are controlled by the boiler’s operating controls. This equipment will also have various indicating and control devices that must not be overlooked in the overall maintenance of boiler controls and safety devices. The Hartford Steam Boiler Inspection and Insurance Company

Pressure Gages Visual display of operating pressures.
Most accurate in their mid-range. Dial range: Power Boilers: 1.5 – 2 times lowest safety valve setting Pressure gages provide a means to visually monitor the pressure in the boiler. For this reason it is important that these be properly installed. An important part of proper installation is to select a gage with the proper dial range. For High Pressure (Power) Steam Boilers, the dial range should be no less than 1.5 and no greater than 2 time the set pressure of the lowest set safety valve on the boiler. The Hartford Steam Boiler Inspection and Insurance Company

Control Water Seals Most controls are designed to be subjected to water pressure. A “loop” or trap is installed to protect controls from direct contact with steam. Condensate fills the lines during normal operation. Most controls and gages are designed to be subjected to water pressure, not direct contact with steam. When these type of controls are installed it is necessary to protect them from direct contact with live steam. This is done by installing a siphon loop. The siphon loop trap will trap condensate in the loop and provide protection from direct contact with steam. The Hartford Steam Boiler Inspection and Insurance Company

Siphon Loops When installing a siphon loop trap it is important that it be installed properly. If installed incorrectly it can result in certain controls malfunctioning due to their being tilted. The Hartford Steam Boiler Inspection and Insurance Company

Safety Valve Body Seat Disc Stem Spring Blow-Down Ring
Huddling Chamber Safety valves are designed for use with steam or other vapor. Review the various parts of the valve as listed in the slide. Spring tension holds the valve disk in place against the valve seat. Steam pressure pushes up from within the boiler. When steam pressure reaches the valve’s set pressure it begins to open the valve. Steam floods the valve, rapidly overcoming spring tension forcing the valve to a full open position almost instantaneously. As pressure in the boiler drops to a preset pressure below the valve’s lifting pressure spring tension once again overcomes steam pressure and fully closes the valve. When installing a safety valve there are several items to pay attention to. Select valves of the proper size to match the boiler fitting, if the boiler attachment point is 2 inches, install a 2 inch safety valve. Make sure that the safety valve capacity is equal to or exceeds the boiler’s maximum generating capacity as shown on the boiler data stamping. Make sure the set pressure of the safety valve is equal to or less then the boiler’s maximum allowable working pressure as shown on the boiler data stamping. Make sure the safety valve discharge is piped to a safe point of discharge to prevent injuries. Discharge piping should be supported so that it does not place any stress on the safety valve. The Hartford Steam Boiler Inspection and Insurance Company

Low Water Fuel Cutoffs Along with the safety valves, the low water fuel cutoffs may provide protection against catastrophic boiler failure. In this case, the LWCO protects the boiler by preventing operation when the boiler water level drops below a minimum allowable level. As we mentioned before, low water is the most common failure of boilers. Preventing low water involves properly maintaining the boiler controls and feedwater equipment. Protecting against low water damage is the function of the LWCO. The Hartford Steam Boiler Inspection and Insurance Company

Low Water Fuel Cutoffs There are basically two types of low water fuel cutoff devices installed in steam boilers. The most common is the external float type as shown here. The other type is the conductivity probe. While not uncommon, they are not very widely used. Power boilers are required by the CSD-1 Code to have two LWCO devices installed, a primary and a secondary. The secondary must have a manual reset switch. It is not uncommon to find these devices installed in such a manner that the primary LWCO shuts down the boiler at a point above the lowest permissible water level and the secondary at the lowest permissible water level. The important point here is that the LWCO must shut the boiler down before the water level drops below the lowest permissible water level. In the case of a Firetube boiler this is 2” above the top row of tubes, for Watertube boilers it is 3” above the top row of tubes in the steam drum. The CSD-1 states that the boiler will shut down when the water level reaches a point not lower than the lowest visible part of the water level sight glass. Section I of the Boiler and Pressure Vessel Code gives us the requirements for placement of the sight glass. Refer to Section I, PG 60.1. The Hartford Steam Boiler Inspection and Insurance Company

Low Water Fuel Cutoffs Proper testing and maintenance of the boiler low water fuel cutoff (LWCO) is one of the most important pieces of maintenance performed on a steam boiler. The number one cause of boiler failures is low water. Low water occurs for one of two reasons, the boiler called for water and did not get it, the boiler needed water but never called for it. Either way, the LWCO is designed to protect the boiler by interrupting burner operation, thus removing the heat source which causes the damage during low water, should a low water condition develop. In this illustration we see the various components of a LWCO. Review the illustration. The Hartford Steam Boiler Inspection and Insurance Company

Low Water Fuel Cutoffs Many boilers use an electronic low water cut out as a secondary low water cut out. A conductivity probe is inserted in the boiler shell at the low water cut out level. When water in the boiler drops below the probe, the circuit is interrupted and the boiler shuts down. Most are equipped with a test button that will either interrupt the boiler or indicate that the device is functioning. The Hartford Steam Boiler Inspection and Insurance Company

Conclusion Follow proper operating procedures Regular maintenance
Be prepared Above all …Work Safely! As we have seen, much of the fundamental maintenance required is simply a matter of following proper procedures for operating, testing, and maintaining boiler controls and safety devices. Regular attention to these maintenance items will not only result in less boiler down time, but reduced operating costs as well. Don’t neglect housekeeping as an important component to boiler room maintenance. A clean, well maintained environment will help prolong the useful life of your boiler as well as provide a safer and more efficient workplace. Above all else, remember to follow all the necessary safety rules when working around and with the boiler. Pay particular attention to following proper lockout/tagout and confined space entry procedures. Keep tools and other equipment used to work on boilers and related machinery in good working order. Not only do the right tools help get the job done, but tools in proper condition make the job safer. The Hartford Steam Boiler Inspection and Insurance Company

Electrical Maintenance
In this next section we’ll be discussing the basics of maintaining an electrical distribution system. In today’s world reliable and efficient electrical power is essential for continued operations. Loose electric power and you’re out of business. The Hartford Steam Boiler Inspection and Insurance Company

Electrical Distribution System
The Hartford Steam Boiler Inspection and Insurance Company

Common Electrical Failures
When looking at the causes of electrical failure, an inadequately maintained electrical distribution system can spell trouble. Loose connections, dusty/dirty electrical surfaces, corroded connections, insulation systems that degrade over time – these electrical failure causes can all be addressed with an effective preventive maintenance program. An important piece of a maintenance program is an inspection of the electrical equipment. “Figure illustrates specific causes of electrical failures and the individual contribution of each cause. This list is based upon twenty years of HSB claims data.” © 2013 The Hartford Steam Boiler Inspection And Insurance Company

Preventing Electrical Failures
Clean Cool Dry Tight In our discussions on electrical equipment maintenance we’ll look at four basic aspects of maintaining electrical equipment. These four key ints are: Keep it: Clean, Cool, Dry, and Tight Let’s look at each of these points. The Hartford Steam Boiler Inspection and Insurance Company

Did you observe any combustible material in the electrical room? Yes
No Did you observe any combustible material in the electrical room? Yes, or No Electrical equipment rooms should not be used for storage, especially of flammable or combustible materials. Access should be restricted only to authorized operations and maintenance personnel. Should an electrical failure occur, materials, such as cardboard boxes, wooden furniture, cleaning fluids or other flammable liquids, will provide a fuel load that can result in a catastrophic fire. Placing items against electrical panels can obstruct air circulation through vent openings that are critical to the proper cooling of electrical equipment. Electrical equipment is designed for specific maximum heat loads. Enclosures and panels are designed to permit air circulation necessary to keep the equipment cool. Blocking vent openings on enclosures, as well a vent openings to the equipment room, can cause equipment to overheat. When you observe electrical equipment rooms being used for storage or that there are flammable or combustible materials in the room, an LPR is to be issued with the appropriate recommendations. Image Source: HSB Files © 2013 The Hartford Steam Boiler Inspection And Insurance Company

Not only might you find electrical rooms being used for storage, but sometimes for other purposes as well. Here the insured thought it would make a nice office space. The venetian blinds at the top of the photo were usually kept down, so that the people working in the office would not have to look at the panels. In one instance, an HSB inspector found an electrical equipment room where a homeless person had set up housekeeping. Image Source: Photo by Edward Springer, HSB Training Coordinator © 2013 The Hartford Steam Boiler Inspection And Insurance Company

Have there been any changes to the electrical system in the last three (3) years?
Yes No Changes to electrical system Such as loads added or relocated or equipment upgraded or replaced. Have there been any changes to the electrical system in the last three (3) years, such as loads added or relocated or equipment upgraded or replaced? Yes, or No The two main questions here are; why were the upgrades made, and who made them? Were designs and specifications made or approved by a licensed professional engineer? Was all work performed by a licensed electrical contractor and done in accordance with local code requirements? Were applicable changes made to system documentation, such as maintenance requirements for new equipment and single line drawings where changes were made? Knowing if loads have been added or reallocated is important since this can have significant impact on the overall system. Upgrades or changes to the electrical system that have not been properly designed or implemented can result in system overloads, or load imbalances, increasing the potential for failures. As well as impacting safety and reliability, system efficiency can be affected as well. Your comments here should address these concerns, as well as others you may observe. Image Source: HSB Files © 2013 The Hartford Steam Boiler Inspection And Insurance Company

Here we see an e;lectrical enclosure that has been allowed to accumulate dust and dirt from the surrounding environment. Notice that thiss equipment has fans installed to assist in cooling. The Hartford Steam Boiler Inspection and Insurance Company

Cleanliness is not only important internal to the equipment but also outside the equipment enclosures as well. Not only can dust and dirt from the surrounding environment migrate into electrical enclosures, as we saw in the previous picture, accumulations of debris that block access to the equipment creates an severe hazard as well. Should that debris consist of combustible or flammable materials the seriousness of the problem is increased. One of the most common problems found with electrical equipment is the use of equipment rooms for storage. The Hartford Steam Boiler Inspection and Insurance Company

Notice that in this picture there is an accumulation of dust on thee ventilation grill for the enclosure. Note that brackets have been attached to allow common household air conditioing filters to be used to fliter air entering the enclosure. While the intention was good, the execution is terrible. Since these filters were not part of the original fabrication they are ineffective in stopping the dust from entering. Also, since the equipment ventilation was not designed for filters, the flow of air in reduced, adding to the problem. The Hartford Steam Boiler Inspection and Insurance Company

In this picture we see an attempt to keep some electrical panels cool. While the effort is laudable, the underlying problem is not being addressed. Here the problem is that the equipment room itself is not being adequately cooled. Maintaining a proper environment for electrical equipment means keeping temperatures within an acceptable range for proper equipment operation. The Hartford Steam Boiler Inspection and Insurance Company

The conductors shown here display the results of inadequate cooling, the insulation on the upper conductors has begun to deteriorate from overheating. The Hartford Steam Boiler Inspection and Insurance Company

Here we see two electrical distribution centers where water has been allowed to attack the equipment. Not only does the resulting corrosion reduce the equipment’s loifespan, it also creates an extremely hazardous conditions for personnel. The Hartford Steam Boiler Inspection and Insurance Company

Everyone knows that electricity and water don’t mix. When a creative custodian saw water leaking out of this electrical pull box, instead of finding the problem to keep water from leaking in, he drilled holes in the sheet metal to allow the water to leak out and not accumulate! (for the non-electrically inclined, a bus bar is not where you go to get a cocktail on your commute home. Bus bars are the large metal bars that carry large amounts of electricity. Virtually all commercial buildings have them). The cheapest “solution” for the custodian was to drill holes in the duct to let the water drain out. HELLO? A really big loss is about to happen here, really soon. The water will act as a conductor and the entire electrical system may short out. What’s worse, an electrical short can ignite a fire. The wiser option would have been to find and fix the leak. Many commercial buildings electrical systems are below ground level or beneath piping and drains so this problem can occur in many places. The Hartford Steam Boiler Inspection and Insurance Company 11

Here we see more evidence of the harmful effects of moisture. The Hartford Steam Boiler Inspection and Insurance Company

In this photo we see the results of a loose connection. These failures can be extremely dangerous due to the resulting arc flash that can occur when the connection fails. The Hartford Steam Boiler Inspection and Insurance Company

Use photo to reinforce point of previous slide The Hartford Steam Boiler Inspection and Insurance Company

Everything “Looks Okay”
The single most important maintenance tool available is infrared thermography. In this picture we see what appears to be a normal electrical panel with no obvious problems. No let’s take a look at thiss same panel in infrared. Note the area highlighted. Everything “Looks Okay” The Hartford Steam Boiler Inspection and Insurance Company

…However! The Hartford Steam Boiler Inspection and Insurance Company
The infrared image shows us that there is a severe overheating problem with the center connection terminal. Discovering these problems before the result in a failure can save many thousands of dollars as well as preventing a possible shutdown of facility operations. The Hartford Steam Boiler Inspection and Insurance Company

Infrared Thermographic Imaging
Detects Hot Spots Dirty, Loose, Oxidized, or Corroded Connections. Finds Phase Imbalance Problems. Finds Undersized Wiring Problems. The Hartford Steam Boiler Inspection and Insurance Company

Surge Protection Surge Protection Device (SPD)
Transient Voltage Surge Suppressor (TVSS) Diverts surge currents to ground Limits the voltage across the terminals of the equipment being protected Another common problem with electrical equipment is the damage from external and internal transient voltage surges. The most common type of sure is, of course, lightning. Yet the most common type of transient voltage surge occurs from line surges to the incoming feed. By installing surge protection devices, referred to as SPD’s, we can provide a high degree of protection to the equipment from both external and internal surges. The Hartford Steam Boiler Inspection and Insurance Company

SPD - Zones of Protection
Zone 1: Service Entrance Equipment Intercept surges before they enter the building Zone 2: Distribution Panel Second line of defense for each panel supplying critical or sensitive electronic equipment Protects against internally generated surges Zone 3: Locally at Each Piece of Equipment Third line of defense Grounding System is key to protection Protection against surges is accomplished by first dividing the entire system into zones of protection. All parts of the system will fall into one of these three zones. The Hartford Steam Boiler Inspection and Insurance Company

Above all else….. SAFETY FIRST!

Have a Safe Trip Home! The Hartford Steam Boiler Inspection and Insurance Company

Preventing Equipment Failures

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Preventing Equipment Failures

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