Infrastructure maintenance and management is incredibly important for the health and safety of the communities relying on sewers and water mains for their daily life. Unfortunately, aging infrastructure is becoming a reality for cities across the globe. According to a report from bipartisanpolicy.org, “unmanaged stormwater threatens the vitality of rivers and streams, while jeopardizing population health and local economies. And much of our drinking water infrastructure is nearing the end of its useful life”. Studies from the American Water Works Association (AWWA) also add that “There are an estimated 240,000 water main breaks per year in the United States. Assuming every pipe would need to be replaced, the cost over the coming decades could reach more than $1 trillion”.
Prioritizing maintenance and repairs is integral for long-term time and cost savings. Water main breaks or blocks, degradation and contamination issues result in massive financial losses. These issues also carry potential prolonged effects on surrounding neighborhoods. Routine inspections on infrastructure including sewage lines, water tanks, and bridges are the first step in preventing these costly issues. Pipe crawler systems are an innovative robotic solution to provide maintenance teams with an instantaneous visual of pipelines.
As a crucial piece of pipe inspection equipment, portable sewer crawler systems allow teams to inspect submerged infrastructure efficiently, conveniently and safely. There are, however, key factors to consider when selecting a pipe crawler.
Different pipe materials and designs affect the performance of a pipe crawler. Additionally, pipe conditions can dramatically vary. Whether the asset is submerged, partially submerged, or containing loose material will dictate the vehicle effectiveness. While some configurations can perform admirably in one situation, it may be rendered useless in another.
In addition to the actual size of the crawler, the type of wheels will seriously impact the effectiveness of the vehicle. It is important to understand which tire or track style is best suited for each material or condition. With this knowledge, you can purchase in confidence knowing that a crawler is well-suited for your project needs.
Rubber wheels are among the most popular options for pipe crawlers. Available in many different wheel and tread sizes, rubber tires are suitable for a wide range of pipe materials. Rubber is strong and very resistant to temperature changes, making for a very versatile wheel material. Concrete pipes are an example of a common material which is best gripped by a crawler fitted with rubber tires. Larger tread options can provide a reliable grip on concrete even through sludge or debris.
Carbide grit wheels combine metal and carbon to provide extra grip and weight. In submerged or partially submerged conditions, PVC and clay pipes may cause a rubber or pneumatic tired vehicle to slip. The extra traction combined with additional weight from a carbide tire set is much better suited for situations like these. Carbide wheels also provide excellent traction in softer pipe material such as clay, as the carbide flakes can grab into the material.
Proven to get traction in mud, sand, gravel and silt, tracks are a great option for the most rugged of pipes. Tracks are a great option for navigating complex obstacles like joints and rocks, or for piloting over the waves of corrugated steel pipes.
While it’s usually not harmful to the vehicle, driving a wheeled vehicle through corrugated steel pipe provides a very unstable video. Tracks are able to alleviate this issue by allowing for a smooth ride across the top of the grooves. It is important to note however that tracks are best suited to larger diameter pipes, as they add significant size to the crawler.
Talk to us about which configurations are best for your pipe inspection projects!
The diameter of the pipe(s) to be inspected is also an important consideration in choosing a pipe crawler. Two main factors should be evaluated; the logistics of navigating the pipe and optimal camera placement.
The crawler body has to be designed to enter the pipe safely while maintaining room to maneuver around turns if applicable. Additionally, for larger pipes the crawler should be adequately sized to tackle any expected debris. Size also plays a role in functional portability for inspection teams. It’s important that the crawler is compact enough to transport and deploy conveniently. This ensures limited time-waste between inspections, as well as effective transportation to remote locations.
To provide the most optimal viewing position for inspections, it’s ideal that the camera is centered within the pipe. To perform NASSCO compliant PACP coded inspections, the camera head needs to be in the center of the pipe. Pipe Trekker crawlers are specifically designed with modular arms to allow users to raise and lower the camera. This provides the option to position the camera in the center of a variety of pipe dimensions. The DT320 can center the camera head in 6-12" (150mm-300mm) diameter pipes and the DT340 or A-200 can center the camera head in 8" - 36" (200mm-900mm) diameter pipes.
For simple visuals and informal checks without certifications, it is less imperative that the camera be centered in the pipe. This dramatically increases the range of applicable crawlers. NASSCO does allow some flexibility within a small range of that center number, and it is really up to the end customer who receives the report on what the ultimate requirements are for the project.
It is crucial that professional pipe crawling equipment be able to integrate with dedicated inspection software. NASSCO’s PACP certification provides municipalities and professionals with a straightforward, standardized way to document sewer conditions and defects. Prior to the development of PACP, the documentation of a pipe’s condition relied heavily on subjective data provided by the operator.
Different inspections performed by different professionals can produce varying reports. One of the main goals of an inspection is to evaluate structural integrity and determine required resource allocation. Subjective data makes accurate decisions difficult. PACP ensures that all operators rely on the same standardized defect coding system, making it easier to objectively compare inspections. This system-wide risk assessment allows teams to determine likelihood of failure and consequence of failure to optimize their budgets.
In addition to creating a consistent, standardized system for inspectors to use, PACP collects data in a format that is conducive to computer processing. This allows a pipe’s condition to be tracked over time and easily compared to other assets.
The standardized method of recording, as well as ease of computer integration, seriously enhances the insight municipalities can gain about their wastewater infrastructure. This pool of valuable information allows municipalities to create strategies that most effectively minimize risk, time and resources, while maximizing return on investment.
Collected data is only as reliable as the tool used to curate it. Using tested and validated reporting programs ensure that teams are provided a convenient import and export using the NASSCO file. There are several NASSCO certified software options that are used to document PACP inspections. Pipe Trekker is proud to offer straightforward WinCan and POSM software compatibility. Integration is also available with GraniteNet, ITPipes,and CTSpec among others.
Understanding how a crawler is powered is another important consideration. There are many power options available, from on board batteries to external power to a CCTV truck. Each option has positive and negative aspects that need to be assessed for each individual project.
Battery powered vehicles are arguably the most convenient and portable, however battery life and charging capabilities may be of concern for extended projects. CCTV truck systems run crawlers through topside power, providing unlimited usage. The issues with utilizing a CCTV truck and topside power is cost and size. These systems are typically massive vehicles costing hundreds of thousands of dollars. This limits opportunities for remote work as well as accessibility for lower-budget operations. Pipe Trekker offers a completely portable hybrid power system utilizing internal lithium-ion batteries. The A-200 operates up to 8 hours on a 1.5 hour battery charge. Rated for 1,000 charge cycles, the batteries are extremely durable. Typically users get several years out of a set of batteries, however they can be easily replaced without needing to replace your entire crawler system.
By offering hybrid power options, the A-200 provides unprecedented versatility. The entire system can be driven into remote locations or shipped cross-country using the included Pelican carrying cases. Conversely, the A-200 and its controller can run direct power, enabling you to operate continuously just like a CCTV truck.
Maintenance is an inevitable part of most types of equipment, especially in large or complex systems. Persistent maintenance can increase costs, decrease efficiency, and impact safety if left unaddressed. The amount of resources you are willing to spend is a crucial factor to consider when choosing a crawler.
Pipe Trekker crawlers are unique in the way they are manufactured and tested. The use of magnetically coupled drives means that the wheel assembly has an opposing magnet to the drive assembly. This locks into place as a water tight assembly without the need to pressurize the crawler (otherwise known as “gas” it or fill it with nitrogen) to maintain its waterproof integrity.
Many crawlers on the market require ongoing greasing or oiling for operation. The only recommended ongoing maintenance for Pipe Trekker systems is regular cleaning after usage. It is also recommended that users charge the batteries every 4-6 months even if it hasn’t been used to ensure battery health.
Pipe inspections can be a tough job. To keep up with the harsh environments of storm and wastewater pipes, each Pipe Trekker crawler goes through extensive testing prior to delivery. Every unit endures a 50 stage Pre-Delivery Checklist, which includes a simulated rough terrain test, high pressure test and low pressure wet test among other drive tests.
There are many major factors to consider when purchasing a pipe crawler for underwater and submerged infrastructure inspection and maintenance. After reviewing this article, you should feel confident about the benefits of each wheel configuration, product dimension, software integrations, and maintenance requirements to pick the best unit for your projects.
As always our team of experts is available to answer any questions you may have. When you’re ready to take the next step and get a pipe crawler of your own, reach out for your customized quote.
Sewer systems are a network of underground pipes for wastewater to travel through. When water is flushed out of a house or business, the sewer pipes beneath roads and lawns carry this waste to a treatment facility.
Three main types of sewer systems often shape sewer inspection:
- Sanitary: Simply referred to as sewers, sanitary sewers carry wastewater from homes and businesses to wastewater treatment plants.
- Storm: Also known as surface water systems, storm sewers channel rainwater and snowmelt into rivers, streams and other bodies of water. Learn more about Storm Systems here.
- Combined: A combined sewer system uses a single pipe to carry both wastewater and surface water to a wastewater treatment plant.
In modern practice, separate sanitary sewers and stormwater lines have replaced most combined systems. In wet climates, increased runoff water combined with the wastewater from buildings causes combined sewers to overflow. Any time this happens, there is a risk of raw sewage spilling directly into public spaces. This puts any of the surrounding natural water supplies at risk of contamination.
With the use of separate sanitary and storm sewers, there is less risk of environmental damage. By separating the two water levels, wastewater can safely travel to a treatment facility with much lower risk of flooding during inclement weather. If a separate stormwater line were to overflow during severe rainfall, there would be no risk of external contamination due to the neutrality of the water.
There are often pipes adjacent to stormwater lines in separate sanitary sewer systems. These pipes handle wastewater flushed from industrial sites, showers, sinks, toilets and laundry. Water enters the sewer system via relatively small pipes, typically 2-6”. These pipes transfer residential and commercial waste away from the building towards septic systems or the sewer main.
Sewage travels through urban wastewater systems to various headworks that screen out debris. Though most wastewater can flow by gravity, sewer systems may require pumping stations for low-lying areas. Once at the treatment facility, the sewage goes through a series of stages before the facility recycles it back into the water network.