Dry breaks or Manifold?

What flow rate do you need out of your next tank truck?


In this video we are looking at the purchasing decisions that are made when deciding between a tank truck equipped with dry break connections for product selection and a tank truck equipped with an air manifold for product selection. This is a common conversation we have with our customers, and a conversation that is one of the main decision points when looking at the specifications and requirements of your next tank truck.

When planning out your next truck think about the key questions our sales team is going to ask you to validate your choice.

  • What flow rate range does this truck need to operate within?
  • How many gallons is an average delivery for this unit’s operational route?



Dry Break Couplings vs Manifolds

Fuel delivery systems on trailers and tank wagons have evolved over the years. Moving petroleum products from a compartment on a trailer or tank wagon into a storage tank will most likely involve Dry Break Couplings or a Manifold of some sort. Let’s talk about these two methods and the pros and cons of each.

Dry Breaks

For years drivers have used faucet-type valves to deliver fuel. These faucets were installed on the end of a pipe leading to an internal valve and needed a wrench to be opened. This allowed the product to flow into a jumper or swing hose that typically was attached to the suction side of a pump. The problem was with every disconnecting there would be at least a cup or so of product left between the coupler and faucet adaptor creating not only a loss of product but a mess of hazardous material to be recaptured somehow or cleaned up.

Making a dry break or disconnecting without having any product loss was revolutionary. The dry break connections were accepted almost immediately industry-wide. The most popular being a camlock or a bayonet-type coupling. Both are widely used in today’s fuel delivery systems and did solve the loss of product with only a few drops when disconnecting. These dry break couplers still use the same principle as the out-of-date faucets. Couple up to the desired compartment and start the pump. Product flows though these couplings on the way to pump, meter, hose reel, hose and then finally a nozzle. The distance any given product will always depend of where the dry breaks are located.

On a rear delivery style system, the trip is a long one. Product will travel from any given compartment to the rear of the tank, back up to the pump, typically located just under the truck, back to the meter and hose reel at the rear. Every inch a pump is pulling or pushing product will affect the efficiency or in this case the gallons per minute. These couplers and adaptors also require to be switched once the compartment is emptied.

Manifolds, Air and Mechanical

Manifolds are nothing new to moving product from multi-sources to a single point. In the case of fuel delivery, they take the place of needing to couple and un-couple to any certain compartment. With fuel delivery, manifolds utilize the same chamber to connect two or more compartments on a trailer or tank wagon. As you may imagine, this can be a source of comingling or contaminating products during deliveries. This occurs when an operator chooses two compartments with different products to pass through the manifold at the same time. This most commonly occurs when the compartments are mislabeling or the operator simply makes an error during the delivery.

Manifolds have many more benefits over dry breaks:

  • Sealed System. No waste or product to clean-up.
  • Better Flow. Ease of product flow to and from the pump on its way to the nozzle.
  • Compartment Tie-Together. Utilize any combination of compartments. Easy to make a 5-compartment tank look and act like a 4, 3, 2 or single compartment unit.
  • Seneca Tank Pro-Air Panel. Allows operator to set controls for the day to minimize risk of comingling product.
  • Increased Pumping Speeds. GPM speeds are higher than dry break systems using same pumps, meters, hose size and nozzles.


- Mark Menard, Area Sales Representative



      Manifold image for dry breaks vs manifold blog