Weir Warman 650 M200-MCR-G, Руководство пользователя

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TOROMOCHO PROJECT - WEG MOTORS
TAG´s :
210-PP-001-M 210-PP-003-M 210-PP-101-M
210-PP-002-M 210-PP-004-M
measured with a MEGGER. In the event that insulation resistance be inferior to the values coming from the above
formula, motors should be submitted to a drying process. This drying process should be carried out in a stove, where
the rate of temperature rise should not exceed 5ºC per hour and the temperature should not exceed 110ºC.
3 – INSTALLATION
Electric machines should be installed in such a way to allow easy access for inspection and maintenance. Should the
surrounding atmosphere be humid, corrosive or containing flammable substance or particles, it is essential to ensure an
adequate degree of protection. The installation of motors on ambients where there are steams, gases or dusts,
flammable or combustible materials, subject to fire or explosion, should be undertaken according to appropriate and
governing codes, such as ABNT/IEC 7914, NBR 5418, VDE 0165, NEC-ART. 500, UL-674.
Under no circumstances motors can be enclosed in boxes or covered with materials which may impede or reduce the
free circulation of cooling air.
Machines fitted with external ventilation should be at least 50cm far from the wall to permit air movement.
The place of installation should allow for air renewal at a rate of 20 cubic meter per minute for each 100kW of motor
output considering ambient temperature of 40ºC and altitude of 1000 m.a.s.l.
3.1 - MECHANICAL ASPECTS
3.1.1 – FOUNDATION
The motor base must be level and as far as possible free of vibrations. A concrete foundation is recommended for
motors over 100 HP (75kW).
The choice of base will depend upon the nature of the soil at the place of installation or of the floor capacity in the case
of buildings. When designing the motor base, keep in mind that the motor may ocasionally be run at a torque above that
of the rated full load torque.
Based upon Figure 3.1, foundation stresses can be calculated by using the following formula:
F1 = 0.5.g.G - 4 Tmax A
F2 = 0.5.g.G + 4 Tmax A
Fig. 3.1 - Base Stresses
Where:
F1 and F2 - Lateral Stress (N)
g - Gravity Force (9.8m/s²)
G - Motor Weight (kg)
Tmax - Breakdown torque (Nm)
A - Obtained from the dimensional drawing of the motor(m)
Sunken bolts or metallic base plates should be used to secure the motor to the base.
3.1.2 - TYPES OF BASES
a) Slide Rails
When motor drive is by pulleys the motor should be mounted on slide rails and the lower part of the belt should be
pulling to avoid belt sleppage during operation and also to avoid the belts to operate sidewise causing damage to
bearing shoulders. The rail nearest the drive pulley is positioned in such a way that the adjusting bolt be between the
motor and the driven machine. The other rail should be placed with the bolt in the opposite position, as shown in Fig.
3.2.
The motor is bolted to the rails and set on the base. Drive and driven pulley centers must be correctly aligned on the
same way, motor and driven machine shafts must be parallel. The belt should not be overly stretched, see Fig. 3.10.
After the alignment, the rails are fixed, as shown below:
Fig. 3.2 - Positioning of slide rails for motor alignment.
b) Foundation Studs
Very often, particularly when drive is by flexible coupling, motor is anchored directly to the base with foundation studs.
This type of coupling does not allow any thrust over the bearings and it is of low cost.
Foundation studs should neither be painted nor rusted as both interfere with the adherence of the concrete, and bring
about loosening.
Fig. 3.3 - Motor mounted on a concrete base with foundation studs.
c) Metallic Base