CN217761412U - Protection device of canned motor pump - Google Patents

Abstract

The utility model discloses a protection device of canned motor pump, including instrument box, canned motor pump, axial displacement determine module overlaps on canned motor pump tail-bar, and axial displacement determine module includes that automatic constant temperature shielding sheath and metal bear the pressure cover, bears the pressure and set up a no magnetism and do not have the skeleton between the cover at automatic constant temperature shielding sheath and metal. The utility model discloses a set up axial displacement detection subassembly and detect to axial displacement on the canned motor pump tail-bar, axial displacement detection subassembly is outmost to be provided with automatic constant temperature shielding sheath, guarantees that the inside temperature of axial displacement monitoring subassembly is in the constant state. When the rotor has axial displacement, the two output coils generate voltage difference, the voltage signal is converted into displacement signal through operation and transmitted to the central control room, and when the displacement of the shaft exceeds a set value, the shutdown command can be sent remotely to protect equipment.

Description

Protection device of canned motor pump

Technical Field

The utility model relates to a displacement measurement technical field, in particular to shield pump's protection device.

Background

The canned motor pump connects the pump and the motor together, the rotor of the motor and the impeller of the pump are fixed on the same shaft, the rotor of the motor and the stator are separated by a sheath, the rotor runs in the conveyed medium, and the power of the rotor is transmitted to the rotor through the magnetic field of the stator. The canned motor pump has the characteristics of full sealing, stable operation, low noise, no need of adding lubricating oil, high safety and the like, and is widely applied to toxic and harmful liquid conveying in chemical and medical industries, fuel filling before launching of spacecrafts, nuclear-grade canned motor pumps for nuclear power stations, fire-fighting water and tap water pressurization systems and the like. When the canned motor pump normally operates, the rotor of the canned motor pump is abraded due to excessive axial displacement, and then the whole canned motor pump is damaged, so that the improvement of the accuracy of axial displacement detection is an important means for protecting the rotor of the canned motor pump and prolonging the service life of the canned motor pump.

For the shield pump used in industrialization, when the axial displacement detection device measures a high-temperature medium, the large temperature change causes physical expansion to cause relative deformation between the iron core and the winding, so that the axial displacement detection device generates a measurement error and cannot accurately reflect the operation condition of the shield pump.

Disclosure of Invention

Based on the problem that prior art exists, the utility model aims at providing a do not receive the temperature variation to influence and can accurate measure canned motor pump rotor axial displacement's device, and then protection canned motor pump, the life of extension canned motor pump.

The technical scheme of the utility model is that: a protection device of a canned motor pump comprises an instrument box, the canned motor pump and an axial displacement detection assembly; a tail rod is arranged at one end of the shield pump, and the axial displacement detection assembly is sleeved on the tail rod; the axial displacement detection assembly comprises an automatic constant-temperature shielding sheath and a metal bearing sleeve, and a non-magnetic and non-inductive framework is arranged between the automatic constant-temperature shielding sheath and the metal bearing sleeve; the outer side of the non-magnetic and non-inductive framework is surrounded with an excitation coil and two output coils, the two output coils are positioned on two sides of the excitation coil, and the output ends of the two output coils are reversely connected in series.

The instrument box comprises a transmitter, a digital display meter and an alarm, the transmitter is provided with a group of output ends and two groups of input ends, the output ends are connected with the magnet exciting coils, and the two groups of input ends are respectively connected with the digital display meter and the alarm through signal lines.

The automatic constant temperature shielding sheath is powered by low voltage direct current.

The instrument box is connected with the central control room through a signal line.

The non-magnetic and non-inductive framework is made of fluororubber or silicon rubber.

Compared with the prior art, the beneficial effects of the utility model are as follows: the utility model discloses a be provided with a excitation coil and two output coils on canned motor pump tail-bar and detect axial displacement, the outmost automatic constant temperature shielding sheath that is provided with of determine module guarantees that the inside temperature of axial displacement monitoring subassembly is in the invariable state, reduces the influence of ambient temperature change to axial displacement determine module measurement accuracy, has effectively improved determine module measuring stability. The digital display meter can set an alarm value, alarm is carried out through the alarm when the alarm value exceeds a set value, the transmitter is provided with two groups of output ends and two groups of input ends, the output ends are electrified to enable the magnet exciting coil to generate magnetism, magnetic flux generated by the magnet exciting coil according to the principle of the transformer is coupled to the output coils on two sides through the tail rods, when the shaft does not displace, the voltages output by the output coils on two sides are not consistent, the transmitter collects a voltage difference and transmits the voltage difference to the digital display meter to display, displacement information can be transmitted back to the central control room, an operator can see the displacement of the shaft, the set value is exceeded, the shutdown instruction protection device can be remotely sent, the structure is simple, and the use is convenient.

Drawings

The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, and together with the description serve to explain the principles of the invention.

Fig. 1 is a schematic structural diagram of the present invention; FIG. 2 is a schematic view of the axial displacement sensing assembly; fig. 3 is a schematic view of the instrument canister.

In the figures 1-3, 1 is an instrument box, 2 is a shielding pump, 3 is a tail rod, 4 is an axial displacement detection assembly, 5 is a nonmagnetic non-inductive framework, 6 is an excitation coil, 7 is an output coil, 8 is an automatic constant-temperature shielding sheath, 9 is a transmitter, 10 is a digital display meter, 11 is an alarm, 12 is a signal line, 13 is a central control room, and 14 is a metal pressure bearing sleeve.

Detailed Description

The preferred embodiments of the present invention will be described hereinafter with reference to the accompanying drawings, and it should be understood that the preferred embodiments described herein are merely for purposes of illustration and explanation, and are not intended to limit the present invention.

Wherein like reference numerals refer to like parts throughout.

As shown in fig. 1-3, the utility model provides a protection device of canned motor pump, including instrument box 1, canned motor pump 2, axial displacement determine module 4, canned motor pump 2's one end is provided with tail-bar 3, axial displacement determine module 4 covers on tail-bar 3, axial displacement determine module 4 includes that the metal bears and presses cover 14 and automatic constant temperature shielding sheath 8, it does not have magnetism noninductive skeleton 5 to set up between cover 14 and automatic constant temperature shielding sheath 8 to bear and press the metal, the outside of no magnetism noninductive skeleton 5 is encircleed there are an excitation coil 6 and two output coil 7, two output coil 7 are located excitation coil 6's both sides, two output coil 7 outputs adopt reverse concatenations. The instrument box 1 comprises a transmitter 9, a digital display meter 10 and an alarm 11.

Another embodiment differs in that the instrument canister 1 is connected to a central control room 13 via a signal line 12.

The difference of the other embodiment is that the non-magnetic and non-inductive framework 5 is made of fluororubber or silicon rubber.

The difference of another embodiment is that when the rotor of the shield pump has no shaft displacement, the tail rod 3 is located at the middle position, the voltages generated by the two output coils are equal, the differential voltage is zero, and no voltage is output from the output coil.

The other embodiment is different in that when the shield pump rotor has axial displacement, the tail rod 3 is located at a position deviated from the middle position, the voltage generated by the output coil on one side is high, the voltage generated by the output coil on the other side is low, the output coil has output and is transmitted to the transmitter 9, the voltage signal of +/-10V is correspondingly output and is transmitted to the digital display meter 10 through calculation in the transmitter 9, the digital display meter 10 corresponds to the axial displacement of +/-6 mm according to the voltage signal of +/-10V, and simultaneously, the current signal can be transmitted back to the central control room 13 according to the axial displacement of +/-6 mm and corresponds to the current output of 4-20mA, and an operator can set an axial displacement alarm value of the shield pump rotor and can remotely send a shutdown command to protect the shield pump if the axial displacement alarm value exceeds the set value.

The difference of another embodiment is that the digital display meter 10 can also set an alarm value, and an alarm signal is sent out through the alarm 11 when the alarm value exceeds the set value.

The other embodiment is different in that the automatic constant-temperature shielding sheath 8 is supplied with +/-5V low-voltage direct current, the constant temperature value can be manually set according to needs, the constant temperature set value is 8-12 ℃ higher than the temperature of the shielding pump medium, the temperature in the axial displacement monitoring assembly 4 is ensured to be in a constant state, and the error between the set value temperature and the actual temperature is +/-0.5 ℃.

The other embodiment is different in that the pressure bearing range of the metal pressure bearing sleeve 14 is 0-30MPa, the temperature change range of the axial displacement detection assembly 4 is less than or equal to 120 ℃, and the measurement error of the axial displacement detection assembly 4 is +/-0.005 mm.

The difference of another embodiment is that the transmitter 9 is provided with a group of output ends and two groups of input ends, the output ends are connected with the magnet exciting coil 6, and the two groups of input ends are respectively connected with the digital display meter 10 and the alarm 11 through signal lines 12. The output end is electrified to enable the excitation coil 6 to generate magnetism, magnetic flux generated by the excitation coil 6 according to the transformer principle is coupled to the output coils 7 on the two sides through the tail rod 3, when the shaft does not displace, the voltage coupled by the output coils 7 on the two sides is equal, when the shaft displaces, the voltage output by the output coils 7 on the two sides is inconsistent, and the voltage difference collected by the transmitter 10 is transmitted to the digital display meter 10 to be displayed.

The difference of another embodiment is that when the shield pump 2 is used for delivering a medium with a higher pressure, the metal pressure-bearing sleeve 14 can isolate the medium from the axial displacement monitoring assembly 4, so as to prevent the high-pressure medium from flowing out.

Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the embodiments described in the foregoing embodiments, or equivalents may be substituted for elements thereof. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (5)

1. A protection device of canned motor pump which characterized in that: the device comprises an instrument box, a shielding pump and an axial displacement detection assembly; a tail rod is arranged at one end of the shield pump, and the axial displacement detection assembly is sleeved on the tail rod; the axial displacement detection assembly comprises an automatic constant-temperature shielding sheath and a metal bearing sleeve, and a nonmagnetic and noninductive framework is arranged between the automatic constant-temperature shielding sheath and the metal bearing sleeve; the outer side of the non-magnetic and non-inductive framework is surrounded with an excitation coil and two output coils, the two output coils are positioned on two sides of the excitation coil, and the output ends of the two output coils are reversely connected in series.

2. A shield pump protection device according to claim 1, wherein: the instrument box comprises a transmitter, a digital display meter and an alarm, wherein the transmitter is provided with a group of output ends and two groups of input ends, the output ends are connected with the magnet exciting coil, and the two groups of input ends are respectively connected with the digital display meter and the alarm through signal lines.

3. A shield pump protection device according to claim 1, wherein: the automatic constant temperature shielding sheath is powered by low voltage direct current.

4. A shield pump protection device according to claim 1, wherein: the instrument box is connected with the central control room through a signal wire.

5. A shield pump protection device according to claim 1, wherein: the non-magnetic and non-inductive framework is made of fluororubber or silicon rubber.

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