Bulk Carriers (Bulkers): All You Need to Know and Their Various Types

October 8, 2020

Today we’re talking about bulk carriers. Bulk carriers, also known as bulkers, are ships that transport unpackaged bulk cargo across bodies of water.

In short, you use a bulk carrier when it’s time to move tons and tons of one commodity. An example of typical bulk cargo material that bulkers will transport includes grains, coal, metal ore, steel coils, and cement. Often, the bulk cargo is simply measured by weight because it’s unpackaged.

Consider this article your go-to guide with everything you need to know about bulk carriers. Permission to climb aboard?!

Barges and the Mighty Mississippi River

When I think of bulk carriers, I picture barges on the Mississippi River. I live in a Midwest metropolitan area along that river. I even lived in a waterfront property along the mighty Mississippi for several years.

Life along the Mississippi often filled me with inspiration. I love a good sunrise or sunset on any body of water. Throughout it all, regardless of the season, barge traffic is the one constant. Night and day, barges carrying coal and grain churn up and down the river.

What’s a Bulk Carrier?

As noted above, a bulk carrier is a ship constructed with cargo spaces intended to carry dry cargo in bulk. The purpose of bulkers is simply economy of scale. By shipping commodities in enormous bulk amounts, a business can maximize capacity of a vessel as well as efficiency and total cost.

Put another way, think about the difference between a bulk shipment of grain and a container ship loaded with loaves of bread. There’s no comparison in terms of how much you can ship at a time and what the profit margins are. It just makes sense to ship in bulk when you need capacity, efficiency, and overall cost. To further illustrate, one standard, fully loaded, 15-unit river barge takes 1,050 trucks off U.S. highways. Think about how much safer that makes the roads!

In addition, enormous cranes are one common feature of ocean bulkers. These cranes, along with conveyors and even heavy machinery like bulldozers and excavators, seem like they belong on a construction site. Instead, that’s how people remove all that freight from the boat.

Majors and Minors: What Are Typical Dry Bulk Commodities?

Dry bulk commodities are typically divided into two categories: major and minor.

About two-thirds of global dry bulk trade consists of major dry bulk commodities. The following are examples of the major dry bulk commodities:

• iron ore
• coal
• grain

Minor bulks make up the remaining one-third of global dry bulk and typically include the following commodities:

• finished steel products
• sugar
• cement
• phosphate
• lumber or logs
• fertilizer

What Are the Different Types of Bulk Carriers?

Dry bulk carriers are similar to container ships and tanker ships. For instance, all three types of vessels are designed to float a large amount of cargo from one side of the ocean to the other. That said, the biggest difference has to do with the types of freight each ship carries.

Bulk carriers typically ship dry bulk commodities, which we’ll cover in detail below. We’ll note the different types and sizes of bulk carriers in the next section. Tankers carry fluids, such as petroleum products and chemicals. On the other hand, container ships carry stacks and stacks of containers. Each container is packed with various types of freight. These ocean vessels are the biggest the world has ever seen.

An Important Drawback of Bulkers

The downside to shipping anything using bulk carriers is the time factor. Bulkers are slow. Why are they so slow? Certain ocean-bound bulk ships are so big that they don’t fit in the Panama Canal. That means a ship must take the long way around Cape Horn at the southernmost tip of South America. Unfortunately, that extra mileage can add weeks of extra time on the water.

Types & Sizes of Bulk Carrier 

Ocean-going bulk carriers fall into six major size categories. Experts determine these sizes based on how much weight (also known as deadweight tonnage, or DWT) a ship can hold. DWT means the total weight a ship can hold. It includes not only cargo but also crew members, passengers, the food those people will need, and the weight of the fuel.

Smaller Bulkers

As you would expect, smaller ships are more nimble and thus more versatile. Here are the first three categories—the smallest ones:

• Mini-bulk: carrying capacity up to 10,000 DWT
• Handysize: carrying capacity 15,000 to 35,000 DWT
• Handymax: carrying capacity 35,000 and 48,000 DWT

Even though these are small vessels compared with the next category, the average person would consider them enormous. One DWT is 2,240 pounds.

Larger Bulkers

In contrast to the smaller vessels, the largest vessels may lack nimbleness, but they make up for it in sheer size. Whether a ship fits through the Panama Canal determines its class.

• Panamax: fits through the Panama Canal; capacity range 68,000 to 120,000 DWT
• Capesize: Doesn’t fit through the Panama Canal; capacity range 156,000 to 400,000 DWT
• Very large or Valemax: 380,000 to 400,000 DWT

Now that’s what I call moving some freight!

It’s important to understand the risks you may face by using bulkers, so let’s tackle that topic next.

The Inherent Risk Factor of Bulkers

The transport of bulk cargo involves a higher level of risk than many types of freight. First of all, since bulk cargo is unpackaged, a potential spill would put that material directly into the environment. As we know, any spills or accidents can be extremely difficult to clean up. Damage to humans, the environment, wildlife, and property can be catastrophic and costly to all parties involved.

The problem is simply inherent to the freight. In choppy water, bulk freight tends to shift, which throws off the balance of a ship. If a big enough wave hits a ship, it can shift all the freight to one side, and the ship will roll. In addition, bad weather can fill cargo holds with seawater, further upsetting the ballast of a ship. Another risk factor to ship safety is the corrosive nature of some types of freight and the saltwater environment.

The Future of Bulk Carriers

When I think of shipwrecks, I think of the Exxon Valdez, all the cruise ships that capsized, and One-Eyed Willy from The Goonies. Somehow I missed the fact that 99 bulk carrier ships sank from 1990 to 1997 alone!

Most shipwrecks occur on old ships. For example, when seals corrode, they crack. Cracked seals aren’t watertight. And water in a cargo hold is a problem.

Over the last twenty years, improved ship design has limited some of the biggest risks to bulk carriers. Technology has come to the rescue in many other forms as well. Automatic identification systems help track ships by satellite and transceiver. Also, water alarms and measurement systems are now mandatory.

Safety Beyond the Ship

In particular, on the personnel level, the digitized document app developed by Vector is a huge safety feature. Vector allows you to attach all documents and corresponding pictures inside the shipment file and upload it all to the cloud. There’s no more paper to lose overboard. The Vector app also helps document pre-trip inspections. Used properly, Vector can improve the quality and efficacy of safety checks aboard bulk carriers.

I’m certain the mantra on the ocean is the same as it is on the river. Respect the water. All things considered, invest in the right technology, document that cracked seal, and go show it to the skipper.

This post was written by Brian Deines. Brian believes that every day is a referendum on a brand’s relevance, and he’s excited to bring that kind of thinking to the world of modern manufacturing and logistics. He deploys a full-stack of business development, sales, and marketing tools built through years of work in the logistics, packaging, and tier-1 part supply industries serving a customer base comprised of Fortune 1000 OEMs.