When we think about the industries transport serves

Weighing the benefits of a loading arm over traditional hose assembly loading.

The main purpose of the transport industry is to move a product from A to B. The transportation sector consists of many sub-industries including aviation, barge loading and unloading, railroads, tank trucks, and rail car. As part of its vast portfolio Dixon manufactures liquid and dry material transfer products such as railcar connectors, cam and groove, overfill protection, drop elbows, API fittings, and valves.

Dixon’s newest product development is our loading terminal equipment including a rack monitor and loading arm.

Dixon’s loading arms are engineered for long life performance as well as ease of use in the field and can be used to overcome some of the typical issues and complications faced in the transfer of liquids and dry materials in a wide range of industrial applications such as refineries, chemical plants and food & beverage plant.

Once such challenge commonly faced by truck operators is having to lift heavy hose assemblies fitted with API valves onsite. Substituting the hose assembly for a loading arm benefits both the drivers by making loading less labour intensive and the site operators by reducing costs in replacing damaged hoses and API valves. The drivers can connect and disconnect the API couplers  to the adapters on their trucks with ease and the site no longer has hoses lay on the ground which can be damaged  or cause a tripping hazard.

The design of the Dixon loading arm incorporates an additional safety factor by having a steel housing for the torsion spring rather than the conventional plastic housing for better durability and long life performance.

The unique counterbalance adjustment mechanism makes for safe an  .. The Dioxn spring can also be adjusted without having to remove the housing making the loading arm  it safer to adjust and  maintain

Loading arms are becoming the standard choice over hoses for certain applications such as the transfer of liquids and dry materials in refineries, chemical plants, food & beverage processing plants, rail terminals and truck terminals. There are many variables involved in making the decision to purchase a loading arm. They can be based on application, material, location, site limitations, etc. Safety should always be considered first when protecting your most important asset, your employees. Is a loading arm actually a safer option than a standard hose assembly? Let’s dive into a few scenarios and examine the impact on safety.

 Weight

What is the media that is being transferred? Is the weight of the hose an issue? A 4 inch hose assembly filled with liquid could potentially weigh 15 pounds per foot. In this situation you could be asking your employees to drag a 300 pound 20 foot hose assembly. This could contribute to a high potential for back injuries and worker compensation injury claims. Even if the hose was shorter it would still add a significant amount of strain and stress on the worker. Switching this application to a loading arm would reduce the chance of an injury tremendously. The counterbalance mechanism of a loading arm is designed to balance the weight and do the heavy lifting for you and, combined with a handle, it becomes a very ergonomic solution.

Repetitive Tasks

Are the tasks being performed repetitive? A loading arm will be mounted and have a distinct range of motion. A hose can be maneuvered more flexibly, although this movement is typically done by having an employee drag the hose around manually. If the location of the connection point involves consistent location, such as at a fuel terminal, a loading arm application would be the best choice. This application will last longer than a standard hose assembly due to the loading arm being suspended where it can not drag on the ground like a hose can. Many times a hose that is used on a consistent basis can only last weeks or months while a loading arm can last years or even tens of years with proper maintenance. Loading arms can be rebuilt so they can last decades by adding replacement parts and removing the old parts while the entire hose assembly will be replaced when it can no longer function properly. See the how to change a spring video below.

Environment

Are your hoses causing a tripping hazard? Are employees constantly having to step over or go around the hose assembly? A loading arm removes these hazards because they are mounted off the ground. They can be articulated into a folded position, out of the way to provide a cleaner, less-hazardous environment. Are your hoses continuously being dragged? This can cause hoses to wear and burst, causing a spill. If the media is potentially hazardous this could be even more serious than a minor spill clean up.

When choosing between a hose assembly or a loading arm, always examine the three topics above before making your decision. There are many other factors involved, but these three topics can be a quick indicator when studying the safety aspect of your decision. The best way to make an informed decision is to discuss your specific applications and needs with a market specialist. We are always ready to help you make an informed decision and select the right connection.

But comprehensive FloTech tanker based overfill prevention equipment and bottom loading vapour recovery mechanical components

In the refined fuel transportation industries, when it comes to choosing the right gasket or O-ring for the job, it’s important to remember: not all seals are created equal.  If these key components aren’t up to the job, leaks and other problems can occur. The problem is, seals come in a variety of materials and grades—something many people don’t realize.

“For instance, people use the word Viton™ as if it’s a single material,” says Bob Koeninger, group vice president for the Dixon Bayco division. “When in fact, it comes in several grades, and you have to know which grade is compatible with the liquid being transported.”

That’s vital in the fuel transport industry because modern-day gasoline and diesel fuels are comprised of an alphabet soup of additives used to keep engines clean and lubricated, to boost gasoline's octane rating and to reduce harmful emissions. Many of these additional chemicals are solvents, which, over time, degrade rubber seals.

The other problem, explains Koeninger, is that different fuel companies use different additive packages, so it’s important to use a material that works effectively no matter the chemical mix.

Viton™, patented by the Dupont Co. in 1957 and first used in the aerospace industry, is the trademarked name for a fluoropolymer elastomer, known generically as FKM. The synthetic rubber offers outstanding resistance to changes in temperature, chemicals and pressure. “Fluorine, which is the primary agent in FKM, is a chemical that nothing likes to stick to, like Teflon™,” says Koeninger, who has worked at Dixon for nearly 20 years. “Nothing likes to link to it, which means nothing will affect it.”

FKM has been particularly important with the rise of ethanol and other biofuels in the early 2000s, as fuel suppliers were faced with a new additive to deal with. “Seals that will work well with gasoline won’t necessarily work well with ethanol,” says Koeninger. “And seals that are ideal for ethanol, might not work well with gasoline. So you have to specify certain grades of FKM to get compatibility with both.”

The Right Stuff

So how do you know which grade of FKM is right for the job?

Different types of FKM seals differ in fluorine content, durometer and curing method. Typically, the higher the fluorine content used in producing the rubber compound, the higher its resistance to chemical degradation. Seals are graded depending on the amount of fluorine in the mix, and the higher the letter or number, the higher the fluorine content and the more chemically resistant the seal.

So, a seal made from Grade A (or Type 1) FKM, which has a fluorine content of 66 percent, might work fine for general-purpose uses. But you’d want to use a higher grade--B, F or G, for instance--when it comes to transporting or storing oxygenated fuels or biodiesel. Specialty seals, often graded as GFLT, are used in ultra-harsh conditions, such as the oil exploration industry. But, as Koeninger says, “as the alphabet goes up, the price increases. By the time you get to GFLT from A, it’s like one’s made out of aluminium and one’s made out of gold.” But if your application calls for chemical resistance and low temperature then use a GFLT seal, it’s money well spent to avoid possible failures.

Dixon Baylast and Other Materials

After ethanol became a widespread additive in gasoline, Dixon Bayco, working with an outside manufacturer, introduced Baylast, a proprietary rubber polymer that accomplishes many of the same goals as FKM. It works well under low temperatures (to -30°F), and holds up to all current modern fuels. It also helps solve the compatibility problems between seals used for gasoline and/or ethanol. “We conducted extensive testing with many different fuels and found that Baylast will work equally well in either gasoline or ethanol, as long as it’s in refined fuels and a tanker isn’t hauling a 100 percent additive package that goes into gasoline,” says Koeninger.

Another advantage to Baylast, he says, is that it’s less expensive than comparable grades of FKM—and it works just as well.

Other seals used in the industry include those made from EPDM (ethylene-propylene-diene-monomer) and Buna-N (nitrile butadiene rubber). But, Koeninger advises, users have to be careful when it comes to these products for fuel transport. Buna is much less universally resistant than FKM Type 2. Modern fuel additives also tend to attack Buna-N, so it is not compatible with all fuels. EPDM, on the other hand, can be used in 100% ethanol environments, but most tankers load both hydrocarbon fuel and ethanol, which makes it ineffective for most fuel transport work.

When it comes to choosing a material for a seal, gasket or O-ring, the key takeaway is that there is a significant difference between products. Consider all aspects of the application before placing an order. And remember the alphabet, says Koeninger. The higher the letter or number, the more resistant the seal.

Do you have questions about your application? We would love to help. Email a specialist.

How to Select the Proper Loading Arm for Your Application

There are many variables to take into consideration when selecting and designing a loading arm. The configuration, components, applications, measurements, media and site limitations, all must be taken into account for the design. Being able to work through this process in a clear concise manner will ensure that all these variables will be considered in the final build of your loading arm.

Above: A screen shot from our easy to use Loading Arm Order Guide.

Configuration

The first decision to make when selecting a loading arm is the configuration. The typical configurations are a-frame or horizontal. It is common for top loading applications, whether for drums, totes, railcars or over the road trailers, to use horizontal style arms. Alternatively, if the media conveyed is pumped into the bottom of a container truck and filled from the bottom, an A-frame style loading arm is typical installed. We also offer custom styles, sizes and configurations beyond just the standard a-frame or horizontal including scissor style, downfeed, etc.

After deciding on your style the next step is to select upfeed or downfeed. This is typically dictated if the onsite plumbing is pumped from the ceiling or canopy of the loading terminal or up from the ground.

Then choosing left-hand or right-hand counterbalance mechanisms. This is going to depend on how your environment is set up. A quick tip is to use left-hand and right-hand configurations next to each other because they can pivot closer together and won’t interfere with each other due to the cantilevered design.

Component Measurement and Material

Now that the configuration has been decided, selecting the measurements and material is next. Each leg of your loading arm will need to be measured from center of swivel to center of swivel to the nearest foot. Leg A is from the counterweight end to the swivel. Leg B is from the swivel to the coupler end. Materials for each leg could be carbon steel, aluminum, stainless steel and leg B could also be metal hose. The loading arm media will help decide which material is used for each arm based on chemical compatibility and other factors such as strength of material. Most times they are all the same material for horizontal loading arms, however leg B on a-frame loading arms are typically a composite hose or metal hose to allow flexibility in connection points.

Application Information

Now the application will be used to select the rest of the options for the loading arm. What pipe size is required? Typically this selection will be driven by your current setup or flow requirements (GPM). What type of base swivel style (split flange, v-ring or o-ring) will be needed on the loading arm? What type of connection is required on your riser stand pipe: 150 ANSI flange, 300 ANSI flange, TTMA flange or other? This will depend on your current set up, but most arms that we’ve built have been 150 pound flange.

Also dictated by the application, more specifically by the mating end connection of the vessel the loading arm is intended to fill, is the outlet or end connection of the arm. In many cases top loading applications will end with an open pipe cut at a 45-degree angled drip edge or a diffuser. In many cases bottom loading assemblies will use an API coupler to ensure a leak proof connection. While those options are common it is not unusual for loading arms to utilize many other standard couplings found in the Dixon product offering. These include Cam & Groove, Dry Disconnect, Vapor Recovery fittings and more.

For seal selection you can request a seal material such as: buna-N, Viton™, PTFE, FKM A&B, or EPDM, or you can refer to your loading arm specialist to select the proper seal based on your application. Often the temperature of the media and chemical compatibility of the seal material with the media dictates what seals should be used.

Site Limitations

Now that the loading arm is built, it’s important to verify that it will fit properly at your site. Providing your loading arm specialists with any site restrictions will ensure the best fit of your loading arm. The ceiling or roof height from the riser pipe connection distance will ensure that the loading arm will not come into contact with the building. If there are any additional items that add weight that should be accounted for when building your loading arm. A few examples include: vapor hoses, drip buckets, hold-down chains, etc. The range of motion desired is important to discuss prior to the build so we can make sure the arm will provide the motion required for the application. The range of motion can be explained using the clock method (see below).

Sketches/Notes

If there are any additional notes or sketches required providing that will also be helpful to the loading arm specialists. “Pictures are worth 1000 words” so please provide pictures if available and site conditions allowed (for example some facilities require intrinsically safe electronics).

Conclusion

There are many advantages to using loading arms. Safety can be improved and repetitive tasks can become easier for the employees. Relying on your loading arm specialist to verify the design and manufacture your loading arm will ensure a successful product. Our team of loading arm specialists are always here to help design your application. If you don’t see the options that you need reach out to our specialists to discuss custom options. We have a quick order guide to make this process simple, which works through the steps above.

Loading arms are becoming the standard choice over hoses for certain applications such as the transfer of liquids and dry materials in refineries, chemical plants, food & beverage processing plants, rail terminals and truck terminals. There are many variables involved in making the decision to purchase a loading arm. They can be based on application, material, location, site limitations, etc. Safety should always be considered first when protecting your most important asset, your employees. Is a loading arm actually a safer option than a standard hose assembly? Let’s dive into a few scenarios and examine the impact on safety.

Weight

What is the media that is being transferred? Is the weight of the hose an issue? A 4 inch hose assembly filled with liquid could potentially weigh 15 pounds per foot. In this situation you could be asking your employees to drag a 300 pound 20 foot hose assembly. This could contribute to a high potential for back injuries and worker compensation injury claims. Even if the hose was shorter it would still add a significant amount of strain and stress on the worker. Switching this application to a loading arm would reduce the chance of an injury tremendously. The counterbalance mechanism of a loading arm is designed to balance the weight and do the heavy lifting for you and, combined with a handle, it becomes a very ergonomic solution.

Repetitive Tasks

Are the tasks being performed repetitive? A loading arm will be mounted and have a distinct range of motion. A hose can be maneuvered more flexibly, although this movement is typically done by having an employee drag the hose around manually. If the location of the connection point involves consistent location, such as at a fuel terminal, a loading arm application would be the best choice. This application will last longer than a standard hose assembly due to the loading arm being suspended where it can not drag on the ground like a hose can. Many times a hose that is used on a consistent basis can only last weeks or months while a loading arm can last years or even tens of years with proper maintenance. Loading arms can be rebuilt so they can last decades by adding replacement parts and removing the old parts while the entire hose assembly will be replaced when it can no longer function properly. See the how to change a spring video below.

Environment

Are your hoses causing a tripping hazard? Are employees constantly having to step over or go around the hose assembly? A loading arm removes these hazards because they are mounted off the ground. They can be articulated into a folded position, out of the way to provide a cleaner, less-hazardous environment. Are your hoses continuously being dragged? This can cause hoses to wear and burst, causing a spill. If the media is potentially hazardous this could be even more serious than a minor spill clean up.

When choosing between a hose assembly or a loading arm, always examine the three topics above before making your decision. There are many other factors involved, but these three topics can be a quick indicator when studying the safety aspect of your decision. The best way to make an informed decision is to discuss your specific applications and needs with a market specialist. We are always ready to help you make an informed decision and select the right connection.

Click here to discuss your application with a loading arm specialist.

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