Proper alignment of Falk gear couplings optimizes power transmissions while maximizing machine runtime. In contrast, poor alignment causes excess friction, limits efficiency, and decreases the lifespan of gearbox components. When machines are properly aligned, axes of rotation are collinear at the point of power transfer. Typically, this means that the rotation axes of the motor and the pump are in the same line at the power transfer point. In some systems, millimeters of misalignment can cause major problems. If your machinery wears early, coupling misalignment could be to blame. Today, we’re pointing out what signs indicate proper coupling alignment.
During installation and replacement, there are several alignment elements to note. Paying attention to these requirements can help you achieve proper shaft alignment.
Falk Couplings: 3 Things to Look for In Correct Coupling Alignment
1. Ease of Connection and Disconnection
Coupling systems are designed to link up easily. Notice how easy or difficult it is to separate and reunite couplings; an awkward fit can indicate improper alignment. For true alignment, plant engineers should measure it in several ways, using visual indications, feeler gauges, dial indicators, calculations, and/or laser shaft alignment systems.
2. Some Misalignment in Axes Rotation of Adjacent Shafts
Flexible couplings allow for up to 3 degrees of misalignment and some end movement. Coupling flexibility also dampens vibrations and ambient noise. At the same time, too much misalignment can be damaging. Excessive misalignment is also detrimental because it will limit the machine’s runtime. In other words, couplings, bearings, and seals will wear out before their time. For this reason, manufacturers (including Falk) publish alignment tolerance tables defining acceptable misalignment levels, according to RPM and coupling type.
Please note: There is no room for misalignment with rigid couplings. Sleeve, clamped, and compression rigid couplings are designed for precise alignment with no give. (As such, rigid couplings cannot be used when vibrations and shock loads are present.) In rigid coupling setups, misalignment indicates a deeper problem, such as improper coupling selection.
3. No Projecting Parts.
Properly aligned couplings are sleek; they are free of protruding parts. Even small burrs on anchor bolt holes and mounting faces can cause misalignment. Before attempting to align couplings, clean, file away and dress any burrs. Once your system is assembled, do a visual inspection to make sure no parts are sticking out.
Operating conditions add another layer of complexity to coupling alignment. Machines are necessarily adjusted when powered down. However, thermal expansion, torque, foundation movement, and play of bearings can all change when the machine is running. Manufacturers will generally take such variables into account when calculating target non-zero alignment. Thermal off-set information is generally provided. If not, mechanical engineers may use thermal expansion calculations to set up machines properly. (Some sophisticated laser alignment systems are equipped to perform these calculations for you.) Once these thermal calculations are complete, it’s best to use precise laser tools for measuring alignment. By looking for the three elements listed above, and adjusting the line according to unique operating conditions, it is possible to achieve acceptable alignment.
Proper alignment is crucial to effective operations, yet it can be quite complex. To create the ideal alignment, it may be necessary to add shims, correct soft foot, or move the driver. When you’re unsure of how to achieve alignment, you can rely on Mar-Dustrial for intelligent advice. Our decades of experience in paper, pulp, mining and other industrial fields has brought us in-depth knowledge of how misalignment can occur, and how to correct it. Call us today for advice on this, we will be happy to provide insight and advice.
Posted under Tips and Tricks on Thursday, March 19th, 2015