Mining Truck Bellows
For more than thirty years, DBA Silencing has been manufacturing exhaust systems, coolant systems, and air intake systems for mining trucks, logging trucks, and fishing vessels. Of those, our main focus has always been exhaust systems for mining trucks. You can see the various exhaust kits we offer on our website.
When we’re designing a kit, or a custom system, we pay particular attention to the expansion joints. Pipe expansion joints are necessary in systems that convey high-temperature exhaust gases or steam. The expansion joints we use at DBA feature multi-ply bellows fashioned from stainless steel. To make a bellows unit, you take relatively thin-walled tubing and form a corrugated cylinder. These corrugations are commonly referred to as convolutions, and they provide the structural integrity necessary to withstand the system’s internal pressure.
At DBA, we offer a wide range of common bellows sizes. You can see the full assortment of options on our website page for Stainless Steel Multi-Ply Expansion Joints, or on page 65 of our catalogue. That catalogue page also shows the various sizes of Stainless Steel Flex Pipe we have available. Our customers purchase these items both as individual components and as part of our kits. We have a Komatsu 930E kit, for instance, that includes both a bellows pipe and a stainless steel flex connector pipe.
In this kit, as you can see, the bellows pipe is encased in one of our heat-resistant fibreglass shells. You can learn more about our proprietary shell technology by watching this video on our website.
In addition to the items mentioned above, we offer a Bellows Connector Kit. This assembly includes a bellows, a male connector, a female connector, and a pair of V-band clamps. These kits also come in multiple sizes and, as with most of our components, custom lengths are possible should your application require non-standard dimensions.
Why Are Bellows Important?
Mining trucks in the field are often confronted by a daunting array of forces. They have to deal with not only rough terrain and clogging agents such as mud and dust, but also temperature extremes and vibration. Those last two items on the list are particularly hard on exhaust systems, but properly selected bellows will help counteract them. Installing the right expansion joints can often mean the difference between frequent maintenance shutdowns and extended periods of productive use.
When mining trucks are running, their systems are subjected to near-constant vibration. This vibration can result in the misalignment of individual components, as well as undesirable noise. Bellows absorb this type of movement and thus help prevent these sorts of problems. Mining truck exhaust systems also have to deal with temperature-induced expansion and contraction. Because pipe expansion joints compensate for this type of thermal movement, they are sometimes known as “compensators”.
What Forces Do Bellows Help Neutralize?
Axial Compression
When the pipes in an exhaust system expand, the length of the bellows is reduced.
Axial Extension
Conversely, when the pipes in an exhaust system contract, there is an increase in the bellows length.
Angular Rotation
In some situations, pipes shift and bellows compensate by bending into an arc.
Lateral Offset
In other cases, pipes move in such a way that we see a transverse motion in the bellows.
Torsion
Generally speaking, bellows have difficulty handling torsional, or twisting, pressure. This type of stress can reduce the life of a bellows or even cause expansion joint failure. DBA systems are designed to minimize torsional movement.
Source: Movement Capabilities: EJMA- The Expansion Joint Manufacturers Association
Why Choose DBA Bellows?
The bellows offered by DBA Silencing are superior in a number of respects.
1. They are constructed exclusively from multi-ply stainless steel. By using multiple plies of metal during the manufacturing process, we increase both the strength and the flexibility of our expansion joints.
2. Our parts are a fraction of the price of OEM equivalents and, in most cases, are more cost-effective than other aftermarket components.
3. Our bellows are some of the most durable units available. Customers who have grown accustomed to replacing expansion joints every couple of months are delighted to discover that DBA Silencing bellows will often last several years.
To sum up: going with DBA expansion joints will save you money, improve the operation of your mining trucks, and reduce maintenance downtime. If you have questions about our bellows or you’d like to place an order, feel free to send us an email at info@dbasilencing.ca or call us at 1-800-661-5886.