Characteristics of explosion-proof motor
The explosion-proof motor is separated from the explosive gas mixture by the electrical insulation shell which may cause sparks, electric arc and dangerous temperature.. However, this case is not sealed, the explosive gas mixture can be through the shell of the parts of the joint space into the motor. When the ignition source of exposure and the shell of spark and arc, high risk and so on may occur explosion, then vibration motor burst housing will not only damage or deformation and explosion flame or hot gas through a bonding surface gap came, also cannot ignite explosive gas mixture around.
The basic series of low-voltage explosion-proof motor products in our country are YB series of explosion-proof three-phase asynchronous motor, which is the derivative product of Y series (IP44) three-phase asynchronous motor.. The explosion-proof performance accords with GB3836.1 - 83 "explosive environment with explosion-proof electrical equipment requirements" and GB3836.2 83 "electrical apparatus for explosive atmospheres - flameproof electrical apparatus" d "," the provisions; motor power is in the range of O.55 - 200kW, corresponding to the frame size range is as high as 80 - seat machine center 315nun; dI, dIIAT4, explosion-proof symbol is dIIBT4, which is suitable for coal mine equipment factory or fixed IIA, IIB level, temperature group T1 - T4 group of combustible gas or vapor and air to form explosive mixture of places; main body shell protective grade is IP44, also can be made into IP%4, junction box the protective class is IP54; the rated frequency 50Hz, rated voltage of 380, 1660, 1140, 380/660, 660/140V; the motor insulation class is F, but as B class of stator winding temperature rise, the temperature rise has a larger degree. The main types of low voltage flameproof three-phase asynchronous motor derived series: YB series (dIIcT4) (the center height of 80 315mm (YBSO), a series of small power, the center height of 63 - 90mm), YBF series (fan base, center height of 63 160mm, YB) - H series (Marine base, center height is 80~280mm), YB (medium, high base center was 355 - 450mm), YBK series (used in coal mine, the center height of 100 - 315mm), YB - W, B - TH, YB - WTH series (frame center height 80 - 315mm), YBDF WF series (outdoor anticorrosive explosion-proof electric valves, the center height of 80 - 315mm) and YBDC (Series flameproof capacitor start single-phase asynchronous motor, the center height of 71 - 100mm) and YBZS series crane flameproof three-phase asynchronous motor.In addition, there are YB series high voltage flameproof three-phase asynchronous motor (frame center height is 355~450mm, 560 - 710mm). The YB2 series of the joint design of the industry has passed the national identification in the end of four 1, and will gradually replace the YB series, and become the basic series of the explosion-proof three-phase asynchronous motor.. YB2 series a total of 15 frame (frame center height is 63 and 355nmm), the power range is O.12 - 315kW.
Main features
(1) there are two parallel horizontal distribution and radiation distribution of the motor fins, and the parallel horizontal distribution is the main.
(2) the noise limit is lower than the YB series, close to the YB series I noise, and the vibration limits are comparable to the YB series.
(3) the main performance indicators reached the early twentieth Century 90's international advanced level.
(4) full range of selection of low noise deep groove ball bearings, shaft center height above 180mm motor with injection oil discharge device.
(5) the full range of F insulation, temperature rise by B grade assessment.
(6) the enclosure protection level is raised to IP55.
(7) power rating, installation size and speed corresponding relationship with the din42673 consistent, taking into account and Yb series of inheritance and Y2 series of interchangeability and made the necessary adjustment, more effective and applicable.
Dust explosion-proof motor
Dust explosion-proof motor refers to its shell is designed according to the provisions of the conditions of manufacture, can prevent the dust into the motor casing or though not completely prevent the dust from entering, but the intake does not interfere with the safe operation of the motor and internal dust accumulation is not easy to ignite the dangerous, use does not cause surrounding explosive dust mixture explosion motor.
Characteristic
(1) the maximum allowable temperature of the control housing is not exceeding the specified temperature group. At present, the mechanization equipment of the national grain storage storehouse is already used. The national standard for dust explosion-proof electrical equipment is GBl2476.1 - 90 "explosive dust environment explosion-proof electrical equipment".
(2) the housing has a high seal to reduce or prevent dust entering into the housing, even if entering into the amount of the dust entering is not hazardous to the formation of the light.
No spark motor
The non sparking motor means the motor that will not ignite the explosive mixture around the normal operating condition and will not ignite the malfunction in general. Compared with the increased safety motor, except for insulation dielectric strength test voltage, winding temperature rise, te (in the maximum ambient temperature reaches the rated operating final temperature of the AC winding. From the beginning the starting current meter to rise to limit temperature time) and starting current is not increased safety, as there are special provisions outside, other aspects and increase safety motor design requirements.
At present, China has developed and manufactured YW series non-sparking motor (frame center height is 80~315mm). The explosion-proof logo is nIIT3, which applies to the factory containing 2 zones of combustible gas or vapor and air explosive mixture formed by air or vapor in the factory containing the T3 - T1 group. Rated frequency 50Hz, rated voltage is 380, 660, 380/660V. And the motor is adopted F insulation, but according to the B level assessment of stator winding temperature rise value, with larger margin of temperature and high safety and reliability, power 0.55~200kW.
The non sparking motor complies with GB3836.1 - 83 and GB3836.8 - 87 "n" for the explosive environment explosion proof electrical equipment for the electrical equipment of the explosion free electrical equipment. Design focus on the motor seal, the main shell protection level of IP55, IP54, the junction box is IP55. The motor of the rated voltage above 660V, the connector of its space heater or other auxiliary device shall be placed in the box of the individual.
Positive pressure motor
Is a kind of positive pressure type electrical equipment.
Its structure is characterized by:
(1) the quick opening or cover of the housing shall have a device for interlocking with the power source. There is no uniform positive pressure motor series products in China.
(2) the positive pressure of the housing and the main pipe relative to the outside atmosphere remains sufficiently large.
(3) motor shall have safety protection device (such as a time relay and a flow monitor), to ensure adequate ventilation must also be pressure in the shell under pressure automatic protection and alarm device.
(4) the configuration of a complete ventilation system, the motor interior is not likely to affect the structure of the ventilation dead.
(5) the shell and pipe are made of non combustible material and have adequate mechanical strength.
Increasing safety motor
The basic series of low pressure and increasing pressure type YA series are the series of three phase asynchronous motor, which is the derivative product of Y series (IP44) three-phase asynchronous motor.. In line with the explosion-proof performance gb3836.1 - 83 "explosive atmospheres explosion-proof electrical equipment General requirements" and GB3836.3 - 83 "explosive environment with explosion-proof electrical equipment increased safety electrical apparatus" e "," the provisions of; power range for O.55~90kW, corresponding to the frame center as high as 8 - 280mm, explosion-proof mark for eIITl, eIIT2, eiit3, were applied in the factory with temperature group for TL T3 group explosive mixture and with a slight places of corrosive medium; the protection grade of the shell body is IP54, junction box protection grade IP55; rated frequency 50Hz, rated voltage is 380V; motor adopts class F insulation.
It is in normal operation condition does not produce electric arc, spark or high risk of the motor structure, and then take some mechanical, electrical and thermal protection measures, so as to avoid further risk of electric arc, spark or high temperature in the normal or recognized under overload conditions, so as to ensure the safety of the explosion-proof.
High voltage (6kV) Ann type three-phase asynchronous motor series: YA355 - 450, power 160 - 450KW. YA560 - 900, power 500 - 1800kW; YAm355 - 630 water and power 220 - 2500kw; YAKK355~630 - air cooling and power 185 - 2000kW. The 20/2600 - TAKW4000 and 4000kW - increasing - free brushless excitation synchronous motor produced in 1999 is a new type of explosion-proof motor which is suitable for the deep - process hydrogenation of oil refinery.
Low-pressure safety motor derived series of main models: YASO series small power increased safety three-phase asynchronous motor (frame central high 56 - 90mm), Ya - W, Ya - WFl series of outdoor and indoor corrosion increased safety type three-phase asynchronous motor (frame center as high as 8 - 280 mm). YA2, a series of industry joint design work and are being organized to replace the YA series. YA2 series a total of 15 frame (frame center as high as 63 - 355mm), the power range is 0.12 - 400KW, will make China's increased safety motor reaches the international similar products in the 1980s advanced level.
Characteristic
(1) adopts brushless excitation, set rotating rectifier dish and static excitation cabinet, excitation control system is reliable; clockwise polarity slip cast excitation accurate, no impact; excitation system of out of step protection is reliable, and synchronizing ability; circuit design is reasonable, discharge resistance at work not fever; excitation current regulating a wide range.
(2) an enhanced safety type moisture heater is fixed at the bottom of the motor, for heating and moisture resistant when the machine is stopped..
(3) the synchronous machine, the exciter and the rotary rectifying disc are coaxial. The rectifier is located between the main motor and the exciter, or placed outside the bearing block..
(4) the selection of high quality raw materials, electrical and mechanical calculation of the large margin, can meet the operating reliability and temperature requirements of the motor.
(5) F grade insulation is adopted, and the temperature is raised by the B grade..
(6) meet the requirements of the safety explosion-proof motor, take a series of reliable measures to prevent sparks, arcing and dangerous high-temperature, can be safe operation in the explosion dangerous place in the 2 zone.
(7) is provided with perfect monitoring measures; main junction box is arranged for differential protection of safety increased type self balancing current transformer; stator winding installation work and a backup platinum thermal resistance, indexing, PT100; leakage monitor, monitor water cooler leakage; both ends of the base type slide bearings are respectively provided with a temperature display meter and remote signal terminals.
(8) the protection grade of the enclosure is IP54.
(9) changing the conventional water cooling into the upper water cooler, that is, the water cooler is placed in the upper part of the motor.
