Elliott Announces A Faster Way To Expand Small Heat Exchanger Tubes New and improved design expands tubes faster than any Elliott expander before, now at a [...]
Enhanced surface tubing has grown in popularity in recent years, with many different styles and options available. While enhancements are preferred for efficiency, they can pose some challenges to operators. As a result, it’s important to be aware of best practices before working with enhanced tubes to ensure that the job is done efficiently and without any damage.
Alfa Laval ACE, located in Broken Arrow, OK, specializes in heat transfer, separation, and fluid handling technology. With a focus on producing quality air coolers for their customers, rolling consistency was of utmost importance. With their current tube rolling method relying heavily on operator feel to regulate the amount of wall reduction, the accuracy of wall reduction was lower than desired. This resulted in too much time spent re-rolling tubes.
Contractors and maintenance personnel agree, the current method of tube cleaning using a rotary flexible cable to clean chillers is a hassle. The cable is problematic; it breaks, the feeding mechanism jams, and the feeder needs frequent and costly repairs. Substantial downtime is encountered to repair cables and units.
There are two motor power sources that are used for expanding tubes mechanically: electric rolling motors and pneumatic rolling motors. Determining what motor to use for a job will depend on operator preference, availability of electricity or air, and the application.
Expanding tubes after they have been welded can be frustrating for operators. If not rolled properly, tube material can build up and put stress on the weld. In extreme cases the tube material can build up so much that the expander can get stuck in the tube, delaying the job.
Before you can start rolling, you will need to select the right expander for the job. Tube OD, and Wall/BWG will determine the size of the expander. However, there are some other factors to consider, such as tube projection, roll length, reach requirements, space constraints, and whether it’s minimum or average wall tubing.
In general, you want to roll to the lowest wall reduction possible where a tight tube to tube sheet joint can be achieved. The harder the material the less wall reduction required to obtain a tube joint. You should always consult the manufacturer of the heat transfer vessel for specific information before undertaking any maintenance procedures.
Tube pullers grip and pull the tube out from the tube sheet. There are a variety of tube removal tools available and each one has a specific use. Review the quick guide below to make sure you select the right tool for the job.
Getting the right tools for your application is critical in order to complete the job right the first time. One of the most overlooked factors when ordering tooling, is determining whether you have minimum wall or average wall tubing.
