Bulk Liquid Transport: What to Know When Shipping Temperature-Sensitive Products

Posted on May 09, 2019 by Doug Grills

When shipping bulk liquid products, there’s a lot of preparation that goes into making your shipment a success.  From the initial intake of lane and product information to the equipment used in the final delivery, there is a long list of items that must be checked for everything to go right. 

When you’re shipping temperature-sensitive products then, it would follow that there’s a great deal of extra preparation needed.  However, we’ve found that the success of a temperature-sensitive shipment really comes down to three simple questions. 

  • At what temperature will the product be loaded?
  • At what temperature does the product need to be delivered?
  • At what temperature does the product begin to solidify?

Providing accurate answers to these questions will allow your freight agent to make plans that ensure your product will be delivered at the appropriate temperature.

The temperature-sensitive shipping process

For common bulk liquids such as petroleum wax, maintaining heat from loading to delivery is a primary concern.  To keep your products at the appropriate temperature throughout the shipment, a tanker with in-transit heating is often required.

In-transit heating

Bulk liquid tankers with in-transit heating capabilities have a series of steam coil lines along the sides of the tank.  Power from the truck heats and circulates coolant from the radiator through these lines in a continuous cycle.  When running at full strength – typically after 4 hours of continuous driving – this system reaches a maximum temperature of 160˚F. 

Shipping temperature-sensitive productsImportantly, this in-transit system does not actually heat the liquid in the tank.  Rather, it assists in maintaining the product’s existing heat by acting like a thermal blanket.  In other words, it seeks to minimize the loss of heat during transit.

For example, let’s say there is a product that will begin to solidify at 90˚F.  It is being loaded in Pennsylvania on Friday and needs to be delivered in Massachusetts on Monday.  It is going to be loaded at 115˚F and needs to be delivered at or above 100˚F.  Upon its loading into a stainless-steel tank, its temperature – and this is true of any heated liquid product – will immediately drop 3 to 5˚F.  So, if it was originally 115˚F, it is now 110 to 112˚F before even leaving the loading site.

From there, the in-transit heating system will try to maintain that temperature throughout the journey.  But, even with the system running perfectly, you can still expect to lose 3 to 5˚F every 24 hours (again, this is true of any heated liquid product).  The driver will call into dispatch each morning of the journey to report the temperature. 

If it is clear over the course of these temperature readings that the product will fall below the required temperature prior to delivery, then steaming will be needed. 


Tank steaming occurs at most tank wash stations.  The tank wash facility has a steam line that connects its boiler to an external hook up of the tank’s coil heating system (only after the tanker’s lines have been flushed out).  Once this connection is made, the boiler system will apply and build pressure through the steam lines before releasing it.  This process repeats over the course of hours in order to heat the tank. Ideally, the tank will be heated to at least 5˚F above the required delivery temperature so that the driver has a “buffer” to allow for natural temperature decreases. 

Most tank trucks will need to use a steaming system that operates at-or-above 75 PSI.  With anything weaker than 75 PSI, the driver can be stuck at the station for long periods of time.  When you consider that most steaming services run $75 or $80 per hour – on top of the driver’s rates, you could be looking at a very expensive pit stop. 

It is therefore crucial that every load is carefully planned at the outset.  Based on the answers to the three questions listed above – as well as the freight agent’s prior knowledge of the product and shipment – a visit to a suitable tank wash facility can be pre-planned into the trip.  Some consignee locations may even have steam on site.  When that’s the case with your load, it is vital that you inform your freight agent as it can potentially save you a good deal of time and money.

Key considerations

A primary consideration when shipping temperature-sensitive products is the actual loading temperature of the product.  If the loading temperature is reported to be 140˚F but is actually 135˚F when the driver arrives, the entire math of the trip is thrown off substantially.  Because of this, many brokers and bulk freight carriers may pre-plan a “just in case” stop at a tank wash station for loads that wouldn’t otherwise require steaming.

Additionally, it is ideal that the loading temperature is at least 20˚F greater than the required delivery temperature in order to account for temperature losses. 

Another key consideration is whether a tanker with in-transit heating is needed.  In our experience, in-transit systems are of little benefit when dealing with temperatures above the system’s maximum 160˚F output.  Others may disagree, saying that the in-transit system’s “thermal blanket” characteristics help maintain temperatures much hotter than 160˚F.  But, in our experience, that is not the case. 

For these hotter temperatures that can’t be assisted by in-transit systems, a mixture of loading at least 20˚F hotter than the delivery temp and steaming, if necessary, is the best approach.

Turn to Bulk Connection when shipping temperature-sensitive bulk liquids

As detailed above, the process of temperature-controlled bulk shipping comes down to careful planning at the outset.  With over 30 years in the industry and a team of experts that average almost 20 years of bulk shipping experience – including temperature-sensitive specialists – Bulk Connection has the expertise to make sure your load is planned as thoroughly as possible.  To learn more about our nationwide bulk liquid carrier network contact Bulk Connection today



This entry was posted in Bulk Transportation, Liquid Bulk Transport, Freight Brokerage by Doug Grills