electric motors. Location
An open type motor has to be installed in places free from moisture, dust or lint cotton, and you have to make room for maintenance and repairs.
approves drippings engines are used where the environment is more or less clean, dry and non corrosive.
totally enclosed motors can be installed in places where it is excessive dirt, moisture and corrosion, or for use outdoors.
When there are unusual environmental conditions such as high temperature, excessive vibration, etc., Should be used shells and special provisions for the installation.
should always be the engine is the best place possible, which is clean, dry and cool.
Moisture problems do need some special care. Guards or covers should be used to protect electrical conductors that are discovered, and the isolation of the motor input drivers in situations that may occur dripping or spraying oil, water or other noxious liquids, unless the motor is Specially designed for installation conditions.
Foundation
rigid footing is essential to have minimum vibration and alignment place between the motor and load. The best foundations are concrete (cement), reinforced as required, especially for engines and heavy loads. If the concrete has sufficient mass, is a rigid support that minimizes the deformations and vibrations. Concrete can be cast on the ground, structural steel, or on the floors of the building, provided that the total weight of motor, driven machine and foundation do not exceed the established capacity to stop the structure.
Should an engine be mounted on a steel structure all support must be the correct size and strength and be securely fastened for maximum rigidity.
The basis for the engine, either concrete or steel, must be level.
The requirements for a perfectly level base is critical. Usually, to install an engine there are 4 mounting points, one in each corner of the base. All mounting points must be in the same exact plan or equipment does not stay level.
Before casting concrete, it is necessary to mark the position of the anchor bolts firmly, but not stiff. We recommend using a base made of steel between the motor feet and the foundation.
Mount For small motors, it has bases and slide adapters for use in T-frame machines replacing older engines. It is necessary to determine its range to be fitted to the other engine components or equipment such as a gear reducer, special couplings and pumps, in order to make the necessary clearance.
After placing the base in place, and before the fix, you must use supplements that are necessary to level it. To do this you can use a regular bubble level, checking in two perpendicular directions, to ensure that the motor feet will be in the same plane and the base will not warp when tightening the bolts in it. The engine is placed on the base, the nuts are installed and tightened with a torque less than that specified, the press reported should be applied after aligning. In NEMA standards indicated the mounting dimensions with legs or flanges.
is necessary to check the alignment after d ride. Mechanical alignment
The foundation for the motor and driven machine are to provide a fixed and permanent relationship between the motor and load. The foundation should provide a firm anchor to maintain the fixed relationship after aligning.
The engine is placed on your site so as to obtain the correct spacing between the motor shaft and the driven machine.
To adjust the motor position using screw jacks, shims or supplements, etc. By adjusting the motor position must be careful to ensure that each one of its legs have the necessary supplements before tightening the screws, so that you can only enter in the group of shims calibration sheet no more than 0.05 mm (2 mil) thick.
angular misalignment is the degree to which the faces of the 2 coupling halves are out of parallel. To determine how a coupling half is mounted a dial indicator, with its button in the other half supported, and are rotated 360 degrees both axles together, to appreciate the variations of reading.
axial misalignment is the offset between the centerlines of the two-axis machines. Can be determined by the dial indicator mounted on a portion (half) of the coupling, while the probe apparatus supported radially on the other hand, and rotating shafts together after a 360 º.
is essential that the motor and its load are properly aligned to the conditions and actual operating temperatures. If they are well aligned with the ambient temperature can severely misaligned in deformation or differential thermal expansion with increasing temperature. Therefore, alignment should be checked after the motor and driven machine have been wounded to its maximum temperature under load.
After aligning the engine load is fixed in place with bolts as large as possible. It is recommended the possibility of changing a bit the location of pins Anchorage, for this reason these items are installed inside or locked steel pipe products ("drowned") in concrete.
connected motors and machines that are properly aligned when installed later may become misaligned due to wear, vibration, displacement of the base, foundation settlement, thermal expansion and contraction, or corrosion. It is therefore advisable to check the alignment at regular intervals and amended as appropriate. Utility
data plate for easier installation and maintenance.
plates or identification data of the engines provide a wealth of useful information on design and maintenance. During installation information on the plate is of utmost importance for rapid and correct execution of work. The publication
NEMA MG1, Section 10.38, states that the following information must be recorded on the nameplate of every electric motor de4: name of manufacturer, type, frame, horsepower (hp), description of service (time) temperature, speed (rpm), frequency (Hz), number of phases, rated load current (A), Nominal Voltage (V), point to rotate key locked, key point of design, service factor and insulation class. Most
plate data associated with the characteristics electric motor, so it is important that the installer is qualified electrical engineer or technician.
mounting methods that minimize maintenance.
Many of the problems that arise in the other are rooted in the way they are installed. In many cases, the foundation or base plate are poorly designed, poorly constructed, or both. The inevitable result is vibration, misalignment (arrows), bearing damage and even break the shaft or a housing frame which usually involves also a major power failure.
If the engine will be mounted on a concrete base (concrete), it is essential that the foundation is hard to minimize vibration and misalignment during operation. The concrete foundation must be solid, with its foundations deep enough to rest on a firm sub-base. Grout and calzamiento
The bed is of great importance for the strength, rigidity and stability of the foundation. Even the best steel base plates are considered adequate support unless they are locked or drowned in the slurry. It is very important to use the correct grout, and you have to use the recommended mixture of sand, cement and water.
Correct use of shims is also essential for the proper engine installation on the foundation. One way to achieve calzamiento proper supplements is to remove and inspect at each point of support before making the final alignment.
is necessary to consider the reason for the use of shims. Not just to place higher or lower the motor, but also they are well aligned the axes of the machine.
Another essential aspect of a good foundation is stability. Once the base is well made and installed not be modified. Sometimes, excessive heat can create problems. Eg, excessive heat or gas arc welding harm the base. In very dry and warm weather has been the case that a steel base to warp or twist when you receive the heat from one side only and the other side is in the shade.
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