Every utility maintenance program has the same goal. To ensure all service interruptions are limited as much as possible, and only when scheduled maintenance is being performed. There are a lot of industries that do not understand the importance of a preventative maintenance program. This includes scheduling regular cleanings and inspections. Power transmission, distribution, and transmission tower resurfacing must be included, or the result is expensive outages, repairs, and overtime for unscheduled labor. This is in direct opposition to proactive maintenance practices.
Unfortunately, the majority of programs being implemented by the industries of distribution and electrical generation have become ineffective as time has passed. This has resulted in numerous deficiencies. Contamination issues resulting in failure can be prevented with transmission tower cleaning. This requires the insulators to be inspected and cleaned regularly. The majority of distribution level transformers in operation are a minimum of several decades old. Flow coat painting is necessary for the replacement of external coatings.
Flow coat painting offers protection from damage resulting from corrosion. The operational lifespan can be extended by repainting to prevent more damage. You will only need to make a minimal investment. You can protect other equipment through flow coat painting. This includes:
• Line termination
• Supportive structures for bus work
• Cooling equipment
When the steel casings become corroded, the result is often mechanical failure. When you update and implement a preventive maintenance program, including inspecting for cleaning, contamination, and painting transmission and substation equipment, you are handling these issues in the best and most cost-effective means possible. Transmission tower resurfacing is critical for proper maintenance. Transmission tower repairs require innovative methods, view some of these methods here.
Maintenance Methods of the Past
A substantial amount of the national grid is more than fifty years old. The maintenance programs have not been updated in numerous areas. These programs were incorrect when they assumed modern steel structures were safe from failures resulting from corrosion. There were not enough inspections, and high voltage insulator cleanings included. Transformers are not being inspected for rust around the seals and on top. The belief was they would be removed from service and refurbished regularly.
Flow coat painting and transmission tower resurfacing were meant to be included with the refurbishment. Transformers are not being serviced due to the progression of technology and the increase of failure modes. This means you need flow coat painting before any significant work becomes necessary.
Cleanings and Inspections for High Voltage Insulators
The insulating attributes of every high voltage insulator will be decreased as material settles on the surface. This is a complex issue that is extremely difficult to predict. If you do not clean the insulator, you will inevitably encounter several different issues. This includes:
• The occurrence of a flashover
• The formation of arcs
• Potential damage to the equipment
• Unscheduled costs for labor
• An interruption in service
Transmission tower resurfacing will minimize all of the above risks while extending the life of your insulators. You can prevent contaminants from building up with a combination of regular inspections and high voltage insulator cleaning. This will enable you to see damage resulting from other sources, including manufacturing defects and corona effects. These methods are important for cleaning and inspections with no service interruption. These services are available through contractors all over the nation. For more information regarding transmission tower resurfacing, read our blog post on transformer painting electrical transformers.
Contamination of High Voltage Insulators
High voltage insulators are exposed to numerous issues due to pollution. This includes:
• Acid rain
• Engine exhaust
All of these elements are floating through the air and will eventually settle on your insulators. The rain will wash some of them away while the water will cause issues with the oil droplets contained in engine oil. Blown dust and soil result in physical erosion. A conductive layer is formed on the insulator's surface due to the combination of moisture and mineral salts. Even wind will not result in the runoff of this layer. Flow coat painting and regular cleanings can protect your insulators.
Contaminates cause issues by hiding the damage being caused. This can also be handled with regular cleanings. This includes damage resulting from NCI insulators, also called non-ceramic insulators. Corona arrest systems can be installed incorrectly or simply fail. The result is the formation of nitric acid on the insulator surface. This is caused by the ionization of nitrogen found in the atmosphere. The result is a mixture of chemicals causing even more contamination and damage on the surface. This enables carbon trails to form, resulting in sections with less resistance.
The end result is either a flashover or arcing. Cleaning the high voltage insulator on a regular basis will slow down or prevent any damage by eliminating the layer of nitric acid. Read more about the scientific principles.
The Importance of Flow Coat Painting When Rust Appears
Regular inspections, cleanings, and flow coat painting extend the life of the transformer. These steps must be taken as quickly as possible once corrosion and rust appear. Flow coat painting needs to be included with scheduled maintenance once there is rust on the transformer. Once the coating fails in one area, you can be certain it will fail on the rest of the surface fairly quickly. Transmission tower resurfacing is just as crucial for the transformers in the same location, with a similar age and wear and tear becoming visible on the paint.
This means transformer tower resurfacing needs to be scheduled for more than just one transformer each time. To understand the critical importance of transformer tower resurfacing and painting, read our blog post about why transformer painting is essential. This is what prevents deep corrosion from forming and mechanically compromising your transformers. Water intrusion and moisture can be prevented by flow coat painting. This increases the length of time necessary for refurbishment or overhaul. Despite transformers failing due to humidity being below five percent, you will still decrease the risk of an unscheduled interruption in service.
Rust removal and flow coat painting enhance the efficiency of your cooling systems. This includes passively and actively cooled transformers because rust acts as a thermal insulator. This will decrease your transformer losses for:
• Electrical losses
• Loads on pumps
• Operating temperatures
Transformer painting is vital for the prevention of mechanical failure due to corrosion on the cooling system's cooling fins and pipes. Leaks will be prevented from occurring in these areas. This is the most common cause of transformer failure in cooling systems.
Transformer tower resurfacing is important due to the impact of the weather on the exterior while in operation. The steel is protected from oxidation by the paint. This is compromised by:
• Abrasion from blowing dust
• Ultraviolet light
• Thermal cycling
There is no coating that will last indefinitely. Exposure to the elements for decades will damage the coating. Transmission tower resurfacing will eventually become necessary. The first thing to destroy the paint will be the light's focused effect resulting from the combination of water droplets on the transformers and ultraviolet light. As a thin layer of rust forms over the exposed metal, the paint will be lifted off as the progression of rust increases. Any sides exposed to the sun or wind will begin to rust from the top.
Once you see rust on the side of the transformer, you already have a severe rust issue. You will not be able to ascertain the amount of damage to the steel due to corrosion unless you perform a close inspection. The iron oxide layers must be removed. This process causes issues for transformers being serviced. Even if you only see minimal amounts of rust, there may be pinholes that have already oxidized to the other side. This provides entry for water and moisture in the transformer's internal areas.
This can result in oil leaking out or contamination of the oil. Both of these issues will result in severe consequences, including:
• Catastrophic failures requiring expensive repairs
• Compromised transformers
• The necessity of additional maintenance
Mechanical Failures Resulting in Other Equipment
The majority of equipment and structures in a substation are constructed of steel. Unless there is a coating in good condition, the result will be corrosion leading to mechanical failure. To prevent failure of the equipment and structures, regular maintenance and transmission tower resurfacing are necessary. This includes:
• Flow coat painting
Larger, load-bearing structures, including terminating or line origination supports and pylons, are especially vulnerable to corrosion resulting in mechanical failure. The loads on these structures are dynamic. The loads are always being shifted over the entire structure due to the weather. The effect is similar to a bridge due to the deeper penetration of rust into the vital components at a faster rate. The repairs are expensive and complicated. This can be prevented by regularly painting, inspecting, and cleaning of transmission towers to prevent damage from rust.
Other equipment must also be repainted, inspected for rust, and cleaned on a regular basis. Instrumentation transformers are susceptible to a lot of the same issues resulting from corrosion. They can be impacted by moisture contamination in the dielectric oil resulting from a tiny leak caused by rust. This can result in the following issues.
• Damage to the central and adjacent circuits
• Service outage
• Thermal failure
The circuit breakers and switching gears are protected by flow coat painting. The steel enclosures protect the internal components from the weather. This also protects other substation equipment, such as fuse panels. The enclosures are generally made using thin sheet metal of mild steel. Rust will occur more easily and quickly than on heavier or metal equipment.
Regular Inspection, Cleaning, and Repainting
Scheduling regular inspections for corrosion and paint wear is a far less expensive option that the risk or equipment failure and an interruption in service. You can include an inspection in your regular maintenance program for a minimal cost. Even though certain areas are harder to inspect, transmission tower resurfacing remains critical. Most of the inspection is visual because rust stains are washed down the sides by the rain. You need to pay particular attention to any equipment with flat, large tops because they catch the rainwater. This includes transformers.
Transmission tower resurfacing and inspections should be conducted on a regular basis. This includes insulators, transmission lines, and substations. This extends the life of the equipment. Potential flaws and failures can be caught by visual inspections prior to turning into serious issues. There are different methods used for cleaning equipment without an interruption in service. The quality of transmission towers is improving, as can be seen here. As soon as you see rust, you need to have your transmission tower painted to prevent damage from corrosion. This is especially true for transformers.
Preparing the surfaces is the most critical step for substation painting. The paint will not adhere properly if the surface is not clean and solid. Every surface requiring painting must first be cleaned of all:
• Loose paint
Preparing the surfaces is a large portion of the cost due to the specialized equipment required and the amount of time necessary. Flow coat painting is much simpler and faster if only a small amount of rust needs to be removed, and just the surface cleaned. The painting should be planned after the equipment has been used for a long enough period of time, where the coating preventing corrosion is near the end of its life according to the manufacturer, or applicator, for equipment that has already been repainted.
Including painting in your maintenance program helps prevent corrosion from occurring while decreasing the cost of painting because only minimal cleaning will be necessary.
Moving Towards the Future
Maintenance practices should be updated to the current standard. These practices should be reviewed on a regular basis to ensure your equipment is kept in service. The lifespan of transmission towers is limited. You can save money through regular inspections and cleanings. The paint used for the transformers will last for a shorter period than the remainder of the transformer. Transformer tower resurfacing is a less expensive option for ensuring they remain in service until the refurbishment is required.
Structures and equipment constructed of steel are a part of transmission towers. These systems need to be protected from corrosion. Preventative maintenance is the best way to prevent the equipment from becoming damaged due to corrosion. This includes repainting, cleaning, and inspection. Customers demand reliable service. An up to date and aggressive maintenance program is the best way to minimize interruption to service. Repainting, cleaning, and inspection are a cost-effective approach for preventing expensive replacement or repairs.