Everything You Need to Know About Hollow-Back Elbows

Pneumatic conveying systems are widely used in industries that require the transfer of powders, granules, and other dry materials. One of the primary challenges of pneumatic conveying systems is the issue of abrasion, which can cause damage to pipeline components, leading to increased maintenance costs and system downtime. To address this problem, manufacturers have developed the Hollow-Back elbow type, which provides enhanced protection against abrasion, improved structural integrity, reduced material spillage, and easy installation and repair. In this blog, we’ll discuss how Hollow-Back elbows work, the benefits they offer, and their applications in the pneumatic conveying industry.


How Hollow-Back Elbows Work

A Hollow-Back elbow is an elbow that features a hollow area on the back side, which can either be an empty square box or an open rounded channel, that is welded onto a regular sweep elbow. The hollow area serves as a space for the material being conveyed to collect, reducing the amount of material that rubs against the walls of the pipeline. This design provides extra protection against abrasion, reducing the risk of damage to pipeline components and extending their lifespan.

Hollow-Back elbows are typically manufactured using carbon steel or stainless steel, depending on the material being conveyed and the level of abrasion. Carbon steel is an economical choice and can handle moderate levels of abrasion, while stainless steel is more expensive but can withstand extreme levels of abrasion.


New call-to-action


Benefits of Hollow-Back Elbows

There are several advantages to using Hollow-Back elbows in pneumatic conveying systems, including:

  • Enhanced Protection Against Abrasion. Hollow-Back elbows are highly effective at protecting against abrasion. The hollow area on the back side of the elbow allows material to collect, reducing the amount of material that rubs against the walls of the pipeline. This extra layer reduces the risk of damage to pipeline components and extends their lifespan.
  • Improved Structural Integrity. The box chamber design of the Hollow-Back elbow provides additional structural support to the elbow while helping to distribute the material flow more evenly. When combined with a carbon or stainless steel construction, this design reduces the stress on the elbow and the risk of blowouts and other damage.
  • Reduced Material Spillage. The pocket area created by the box chamber design reduces the risk of spillage by giving the material a space to collect, preventing it from spilling out of the elbow. Allowing the materials to settle in the elbow also helps reduce the likelihood of blockages and material buildup, and build-up pressure in the pipeline that could result in blowouts and spills. This design is particularly beneficial for hazardous or harmful materials, as it helps to improve workplace safety and reduces the risk of contamination.
  • Easy Installation. Hollow-Back elbows come in the same size configurations as plain elbows and can be installed using the same end connections. Additionally, the lightweight design of Hollow-Back elbows makes them easy to handle and maneuver into place during the installation process, minimizing installation time and costs and making them a cost-effective solution.
  • Easy Repair. Hollow-Back elbows are easy to repair in the event of a blowout or other damage. The hollow area provides easy access to the elbow's interior, making examining and identifying damage easier without disassembling the entire elbow or cutting it open. This access allows for fast and efficient repairs, which helps to minimize downtime and maintenance costs.


Applications of Hollow-Back in the Industry

Hollow-Back elbows are commonly used for highly abrasive materials that tend to pack, such as the cement, mining, and chemical industries. Hollow-Back elbows are not suitable for all materials, however. Food and materials that can spoil or contaminate should be avoided in this type of elbow. The pocket area of the elbow can be difficult to clean and may pose a risk of contamination.


A Valuable Tool for Pneumatic Conveying Systems

Hollow-Back elbows can be a valuable part of a pneumatic conveying system. They can provide added protection against abrasion for highly abrasive materials and help extend the elbow's life, thus saving time and money on repair and maintenance. 

However, it's important to consider whether it is the right fit for your specific system. Factors such as the design of your system, the number of elbows required, and the product's abrasiveness should be considered. If you have any questions about Hollow-Back elbows or need a quote, contact us at Progressive Products, where we never sell you something you don’t need.

New call-to-action