CN116928150A - Mud pump and mud pump flushing parameter configuration method - Google Patents

Abstract

The invention provides a mud pump and a method for configuring flushing parameters of the mud pump, wherein the mud pump comprises two water inlet guide pipes, the two water inlet guide pipes are arranged in a central symmetry way around the central line of an impeller, one end of each water inlet guide pipe is communicated with a flushing cavity at a suction end and forms a water inlet on a front cover, the other end of each water inlet guide pipe is communicated with an external water source, the length direction of each water inlet guide pipe is consistent with the tangential direction of the flushing cavity at the suction end, the direction of water flowing to the water inlet through the water inlet guide pipe is consistent with the rotating direction of the impeller, the impact of flushing water flow on water flow rotating in the flushing cavity at the suction side can be reduced, and the overflow of the mud pump is reducedWear of the flow components. Mud pump flushing parameter configuration method is based on impeller diameter D _{Leaves of the plant} The proper flushing flow and flushing pressure are calculated by the numerical values of the rotation speed n of the mud pump and the lift H of the mud pump through an empirical formula, so that mud is prevented from flowing back to a gap between the impeller and the wear-resistant lining plate, the working stability of the mud pump is improved, and the construction is facilitated to be smoothly carried out.

Description

Mud pump and mud pump flushing parameter configuration method

Technical Field

The invention relates to the technical field of dredging, in particular to a mud pump and a flushing parameter configuration method of the mud pump.

Background

The dredge pump is a main device of hydraulic dredge engineering ship, which mainly uses the movement of water to complete the dredging purpose, and it cuts the underwater soil layer by mechanical or high-pressure water to loosen, so that the silt and water are mixed to form a mud-water mixture (mud) with a certain concentration, then the mud is sucked into the dredge pump through the vacuum of the dredge pump suction port installed on the ship, and discharged to the dredge cabin of dredge ship or directly discharged to the side dredge barge or conveyed to the dredge area through the dredge pipeline, so as to achieve the dredging and dredge. Thus, the dredge pump is a key device of the dredge, and its hydraulic and wear resistance properties directly affect the dredging efficiency of the dredge.

Because the concentration of the slurry conveyed by the mud pump is higher, the flow-through part of the mud pump is easy to wear. In the prior art, in order to reduce abrasion, a water inlet is usually arranged on a front pump cover, clean water is introduced from outside, namely flushing water is arranged between an impeller and a lining plate, so that abrasion of slurry to the impeller and the lining plate is reduced. As shown in fig. 3, the thick open arrow indicates the mud flow direction and the thin one-way arrow indicates the flush flow direction at the suction end. However, in the dredge pump structure, the flushing water at the suction end is normally an inlet, the flushing water outlet direction is perpendicular to the inner wall of the flushing cavity at the suction end, and the water flow direction passes through the center of the pump. The rivers of bath are impacted the rivers that inhale end bath intracavity was rotatory, caused the disturbance, are unfavorable for silt granule to discharge, and the local vortex backward flow is triggered easily simultaneously, and the wall wearing and tearing to the flow parts are aggravated to the part silt granule in the bath intracavity under the vortex backward flow drives, influence the life and the reliability in the operation in-process of dredge pump, are unfavorable for the going on of construction. In addition, in practical engineering application, the flushing parameters of the mud pump are usually set by operators according to experience or habit, and lack of unified parameter setting rules, so that the mud pump is easy to fail, and the working state is unstable, so that the construction continuity is affected.

Disclosure of Invention

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a mud pump and a mud pump flushing parameter configuration method.

In order to achieve the above purpose, the present invention provides the following technical solutions:

the utility model provides a mud pump, includes the casing that protecgulum, pump case and back lid are constituteed, the inside impeller that is equipped with of casing and this impeller with the protecgulum all be equipped with wear-resisting welt between the back lid, the suction end of impeller is provided with impeller suction inlet wear-resisting ring and suction end water seal assembly, with form annular suction end bath chamber between protecgulum and the wear-resisting welt, still include: the two water inlet guide pipes are arranged in a central symmetry mode around the central line of the impeller, one end of each water inlet guide pipe is communicated with the flushing cavity at the suction end and forms a water inlet on the front cover, the other end of each water inlet guide pipe is communicated with an external water source, the length direction of each water inlet guide pipe is consistent with the tangential direction of the flushing cavity at the suction end, and the water flow direction from the water inlet guide pipes to the water inlet is consistent with the rotation direction of the impeller.

Further, the inner diameter d of the water inlet guide pipe _Pipe The range of the values is as follows:

d _pipe ＝(0.013～0.018)D _{Leaves of the plant} ·L ^-0.5

Wherein L is the vertical distance from the water inlet guide pipe to the central line of the impeller, D _{Leaves of the plant} L, D for the diameter of the impeller _{Leaves of the plant} 、d _Pipe The units of (a) are m.

Preferably, the inner diameter d of the water inlet guide pipe _Pipe Take the value d _Pipe ＝0.0159D _{Leaves of the plant} ·L ^-0.5 。

Further, one end of the water inlet guide pipe, which is far away from the front cover, is provided with a flange, and the flange is used for being connected with a water pipe of an external water source.

The mud pump flushing parameter configuration method is carried out by using the mud pump and comprises the following steps:

step S1, determining the rotation speed n of the mud pump by taking rpm as a unit, and determining the pump lift H and the diameter D of an impeller in the mud pump by taking m as a unit _{Leaves of the plant} ；

Step S2, according to the rotation speed n of the mud pump and the diameter D of the impeller in the step S1 _{Leaves of the plant} The value range of the tangential flushing flow q is calculated by an empirical formula, wherein the empirical formula is q= (0.05-0.1) n.D _{Leaves of the plant} ² In m ³ /h；

Step S3, taking a water flushing pressure p with a value of 1.3 times of a pump lift H, wherein the unit is mH ₂ O。

Preferably, the tangential flush flow q has a value q=0.075 n·d _{Leaves of the plant} ² 。

The invention has the following beneficial effects:

1. in the mud pump, an external water source is led into the flushing cavity at the suction end through the water inlet guide pipe, so that sediment between the flushing cavity, the impeller and the wear-resistant lining plate is taken away. The length direction of the water inlet guide pipe is consistent with the tangential direction of the water flushing cavity of the suction end, and the two water inlet guide pipes are arranged in a central symmetry way, so that the connected water flushing forms annular water flow consistent with the rotation direction of the impeller, the impact of the water flushing water flow on the water flushing cavity of the suction side is reduced, disturbance and local vortex backflow are avoided, the abrasion of the overflow parts of the mud pump can be reduced, the service lives of the overflow parts such as the water sealing assembly, the impeller and the wear-resistant lining plate of the suction end of the mud pump are prolonged, the repair and replacement of vulnerable parts are reduced, the maintenance cost is saved, and the construction continuity and the construction benefit of the dredger are improved.

2. The method for configuring the flushing parameters of the dredge pump provided by the invention is based on the diameter D of the impeller _{Leaves of the plant} The proper flushing flow and flushing pressure are obtained through calculation of the numerical values of the rotation speed n of the mud pump and the lift H of the mud pump through an empirical formula, so that mud is prevented from flowing back to a gap between the impeller and the wear-resistant lining plate, the flushing effect of sediment between the opposite flushing water cavity and the impeller and the wear-resistant lining plate is guaranteed, the working stability of the mud pump is improved, the possibility of failure is reduced, and the construction is facilitated to be carried out smoothly.

Drawings

FIG. 1 is a schematic view of a mud pump according to an embodiment of the present invention;

FIG. 2 is a cross-sectional view of a mud pump in an embodiment of the present invention;

FIG. 3 is a cross-sectional view of an embodiment of the invention at the flush chamber of the suction end;

FIG. 4 is a schematic view of the structure of the front cover in the embodiment of the present invention;

FIG. 5 is a front view of the front cover in an embodiment of the invention;

FIG. 6 is a cross-sectional view of section A-A of FIG. 5; and

fig. 7 is a flow chart of a mud pump flushing parameter configuration in an embodiment of the present invention.

Reference numerals:

10 shell, 11 front cover, 12 pump shell, 13 back cover, 14 water inlet guide pipe, flange 141;

the device comprises a impeller 20, a wear-resistant lining plate 21, an impeller suction port wear-resistant ring 22, a suction end water seal assembly 23, a water seal chamber 24 and a suction end water flushing chamber 25;

30 transmission mechanism, 31 bearing seat, 32 bearing cylinder component, 33 pump shaft.

Detailed Description

In order to make the technical means, creation characteristics, achievement of the purpose and effect of the present invention easy to understand, the following embodiments specifically describe the mud pump of the present invention with reference to the accompanying drawings.

< example >

As shown in fig. 1 to 3, the mud pump of the present embodiment includes a casing 10 composed of a front cover 11, a pump casing 12 and a rear cover 13, wherein an impeller 20 is disposed inside the casing 10, wear-resistant lining plates 21 are disposed between the impeller 20 and the front cover 1 and between the impeller 20 and the rear cover 13, an impeller suction inlet wear-resistant ring 22 and a suction inlet water seal assembly 23 are disposed at a suction end of the impeller 20, and an annular suction inlet flushing chamber 25 is formed between the impeller suction inlet wear-resistant ring 22, the suction inlet water seal assembly 23, the front cover 11 and the wear-resistant lining plates 21.

The rear cover 13 side of the mud pump is also provided with a transmission mechanism 30, and the transmission mechanism 30 comprises a bearing seat 31, a bearing cylinder assembly 32 and a pump shaft 33. Bearing housing 31 is mounted on the deck of the hull for supporting bearing cartridge assembly 32. The pump shaft 33 is disposed in the bearing cartridge assembly 32 and has a front end fixedly connected to the impeller 20, such as by a threaded connection, to rotate the impeller 20.

The rear cover 13 is mounted on the bearing housing 31 by bolts, the pump housing 12 is connected to the rear cover 13 by bolts, and the front cover 11 is connected to the pump housing 12 by bolts. Wear-resistant lining plates 21 on the front and rear sides of the impeller 20 are respectively fixed on the inner walls of the front cover 11 and the rear cover 13 to reduce wear of the housing. The impeller suction port anti-abrasion ring 22 is connected with the impeller 20 through bolt fastening, the suction end water seal assembly 23 is connected with the front cover 11 through bolt fastening, the water seal chamber 24 is arranged on the outer side of the rear cover 13 so as to prevent sediment from wearing the pump shaft 33, and the water seal chamber 24 is connected with the rear cover 13 through bolts.

As shown in fig. 4 to 6, in this embodiment, the mud pump further includes two water inlet guide pipes 14, and the two water inlet guide pipes 14 are arranged in a central symmetry manner around the center line of the impeller 20, wherein one end of each water inlet guide pipe 14 is communicated with the suction-end flushing cavity and forms a water inlet 111 on the front cover 11, the other end is communicated with an external water source, the length direction of the water inlet guide pipe 14 is consistent with the tangential direction of the suction-end flushing cavity, and the direction of water flowing through the water inlet guide pipe 14 to the water inlet 111 is consistent with the rotation direction of the impeller 20 (the tangential water flow direction and the impeller rotation direction in fig. 4 are both clockwise).

Further, a flange 141 is disposed at the end of the water inlet guide pipe 14 away from the front cover 11, and the flange 141 is used for connecting with a water pipe of an external water source.

When the water pump is used, the flange 141 at the port of the water inlet guide pipe 14 is connected with the water outlet pipe orifice of the water pump, clean water is pumped into the water inlet guide pipe 14 through the water pump, water flows tangentially into the water flushing cavity at the suction end along the water inlet guide pipe 14, then the water flows circularly along the inner wall of the water flushing cavity, the rotating direction is the same as the rotating direction of the impeller 20, the flowing impact can be reduced, meanwhile, flushing water flows from the position close to the center of the impeller 20 to the outer edge along the gap between the impeller 20 and the front cover part wear-resistant lining plate 21 and takes away sediment, and the abrasion of the water flushing cavity at the suction end, the impeller suction opening wear-resistant ring 22, the impeller 20 and the wear-resistant lining plate 21 is reduced. Therefore, the mud pump of this embodiment can avoid flushing to impact the rotatory rivers in the suction end bath chamber and cause the disturbance, and the local vortex backward flow of initiation, further avoid the part silt granule in the bath chamber to increase the wall wearing and tearing to the flow passage part under the vortex backward flow drives.

As shown in fig. 7, this embodiment further provides a method for configuring a flushing parameter of a mud pump, which is performed by using the mud pump, and includes:

step S1, determining the rotation speed n of the mud pump by taking rpm as a unit, and determining the pump lift H and the diameter D of an impeller in the mud pump by taking m as a unit _{Leaves of the plant} ；

Step S2, according to the rotation speed n of the mud pump and the diameter D of the impeller in the step S1 _{Leaves of the plant} The value range of the tangential flushing flow q is calculated by an empirical formula, wherein the empirical formula is q= (0.05-0.1) n.D _{Leaves of the plant} ² In m ³ /h；

Step S3, taking a water flushing pressure p with a value of 1.3 times of a pump lift H, wherein the unit is mH ₂ O。

Specifically, according to the mud pump structure of the present embodiment, the flushing water flows tangentially into the suction-side flushing chamber along the inlet guide pipe 14, then flows into the gap between the impeller 20 and the abrasion-resistant lining plate 21, and flows out toward the outer diameter edge of the impeller 20 (as shown by the thin unidirectional arrow in fig. 3). The flushing flow needs to reach at least a specific value under the precondition that the slurry at the outlet of the impeller 20 is prevented from flowing backward into the gap between the impeller 20 and the wear-resistant lining plate 21. The liquid in the gap has a circumferential velocity due to the rotation driving action of the impeller 20, and the liquid has a tendency to move outwards due to the centrifugal action, the circumferential velocity at the outer diameter of the impeller 20, the rotation speed n of the mud pump, and the diameter D of the impeller _{Leaves of the plant} In relation to this, therefore, the flushing flow q, the rotation speed n of the dredge pump and the impeller diameter D required to meet the preconditions _{Leaves of the plant} Related to the following.

The flushing flow required by the mud pumps with different rotation speeds and different impeller diameters is obtained through computer simulation, and the flushing flow q, the rotation speed n of the mud pump and the impeller diameter D are established _{Leaves of the plant} Is a function of:

first, for a fixed mud pump (i.e. controlling impeller diameter D _{Leaves of the plant} Invariable) and repeatedly adjusts the flushing water flow at the same rotating speedThe minimum flush flow rate at which the volume meets the precondition (i.e., flush water flows along the gap between the impeller and the liner plate in the direction of the impeller outer diameter without backflow) is recorded as the flush flow rate q required at that rotational speed. And selecting a plurality of groups of common rotation speed values of the mud pump to obtain the flushing flow q required by the rotation speed. In this embodiment, the diameter D of the impeller _{Leaves of the plant} For example, =2m, the simulation results are shown in the following table:

mud pump rotation speed n (rpm)	Impeller diameter D Leaves of the plant (m)	The required flush flow q (m 3 /h)
			200	2	40
250	2	50
			300	2	60
350	2	70
			400	2	80
450	2	90

From this, it is clear that the required flushing flow rate q and the sludge pump rotation speed n are in direct proportion to the same sludge pump. Let flush flow q=k ₁ n is the coefficient k when the impeller diameter is 2m ₁ The value is 0.2.

Then, carrying out simulation experiments on a plurality of mud pumps with different impeller diameters running at the same rotating speed to obtain the corresponding required flushing flow q of each mud pump when the preconditions are met. In this embodiment, the mud pump rotation speed n=300 rpm is taken as an example, and the simulation results are shown in the following table:

since the known flushing flow q is in direct proportion to the rotation speed n of the dredge pump, a functional relation is established: q/n=f (D _{Leaves of the plant} ) Fitting by least square method to obtain q/n=kD _{Leaves of the plant} ² I.e. f (D) _{Leaves of the plant} ) Diameter D of impeller _{Leaves of the plant} The square of (2) is in a linear relationship, and the average value of the coefficient k is about 0.05, namely:

q＝0.05n·D _{leaves of the plant} ² 。

Finally, considering that the concentration change of mortar conveyed by the mud pump and the gap between the impeller 20 and the wear-resistant lining plate 21 become larger along with the gradual wear and aging of the use in practical application, the flushing flow q needs to be properly increased, so that the value range of the coefficient k is enlarged to be 0.05-0.1, and finally, the empirical formula of the flushing flow is obtained:

q＝(0.05～0.1)n·D _{leaves of the plant} ² 。

The mud weight of the mud transported by the mud pump in actual dredging engineering is usually 1.3g/cm ³ That is, the mud density is 1.3 times of the water, the pump lift H is the pump height of the pump, so 1.3 times of the pump lift H (clear water lift) is equal to the pump lift, and the flushing pressure matched with the pump lift H is determined empiricallyThe value is 1.3 times the lift H.

Further, in order to reduce the disturbance of water flow impact, the water flow speed of the flushing water inlet is the same as the rotating water flow speed in the original flushing cavity, namelyQ= (0.05-0.1) n.d _{Leaves of the plant} ² After substitution, the value range of the inner diameter of the water inlet guide pipe 14 is obtained:

d _pipe ＝(0.013～0.018)D _{Leaves of the plant} ·L ^-0.5 ，

Wherein L is the distance between the corresponding water inlet of the water inlet guide pipe on the front cover and the central line of the impeller (figure 3), L, D _{Leaves of the plant} 、d _Pipe The units of (a) are m.

Preferably, the inner diameter of the water inlet guide pipe is d _Pipe ＝0.0159D _{Leaves of the plant} ·L ^-0.5 。

In this embodiment, the distance L from the water inlet to the centerline of the impeller 20 is 0.57m, and the impeller diameter D _{Leaves of the plant} 2m, the inside diameter of the water inlet guide pipe 14 is taken:

d _pipe ＝0.0159D _{Leaves of the plant} ·L ^-0.5 ＝0.0159×2×0.57 ^-0.5 ＝0.042m。

Preferably, the tangential flush flow q has a value q=0.075 n·d _{Leaves of the plant} ² 。

In this embodiment, taking the rotation speed of the dredge pump of 300rpm, the lift of the dredge pump of 80m and the diameter of the impeller of 2m as examples, the calculation results:

tangential flush flow q=0.075 n·d _{Leaves of the plant} ² ＝0.075×300×2 ² ＝90m ³ /h；

Flush pressure p=1.3h=1.3x80=104 mH ₂ O。

The above embodiments are preferred examples of the present invention, and are not intended to limit the scope of the present invention.

Claims (6)

1. The utility model provides a mud pump, includes the casing that protecgulum, pump case and back lid are constituteed, the inside impeller that is equipped with of casing and this impeller with the protecgulum all be equipped with wear-resisting welt between the back lid, the suction end of impeller is provided with impeller suction inlet wear-resisting ring and suction end water seal assembly, with form annular suction end bath chamber between protecgulum and the wear-resisting welt, its characterized in that still includes: two water inlet guide pipes which are arranged in a central symmetry way around the central line of the impeller,

wherein one end of each water inlet guide pipe is communicated with the flushing cavity at the suction end and a water inlet is formed on the front cover, the other end of each water inlet guide pipe is communicated with an external water source,

the length direction of the water inlet guide pipe is consistent with the tangential direction of the water flushing cavity at the suction end, and the water flow direction flowing to the water inlet through the water inlet guide pipe is consistent with the rotation direction of the impeller.

2. The mud pump as set forth in claim 1, wherein:

wherein the inner diameter d of the water inlet guide pipe _Pipe The range of the values is as follows:

d _pipe ＝(0.013～0.018)D _{Leaves of the plant} ·L ^-0.5

Wherein L is the vertical distance from the water inlet guide pipe to the central line of the impeller, D _{Leaves of the plant} L, D for the diameter of the impeller _{Leaves of the plant} 、d _Pipe The units of (a) are m.

3. A mud pump as set forth in claim 2, wherein:

wherein the inner diameter d of the water inlet guide pipe _Pipe Take the value d _Pipe ＝0.0159D _{Leaves of the plant} ·L ^-0.5 。

4. The mud pump as set forth in claim 1, wherein:

wherein, the one end that advances water guide tube and keep away from the protecgulum is equipped with the flange, and this flange is used for being connected with the raceway of outside water source.

5. A method of configuring flush parameters of a dredge pump using the dredge pump of any one of claims 1 to 4, comprising:

step S1, determining the rotation speed n of the mud pump by taking rpm as a unit, and determining the pump lift H and the diameter D of an impeller in the mud pump by taking m as a unit _{Leaves of the plant} ；

Step S2, according to the rotation speed n of the mud pump and the diameter D of the impeller in the step S1 _{Leaves of the plant} The value range of the tangential flushing flow q is calculated by an empirical formula, wherein the empirical formula is q= (0.05-0.1) n.D _{Leaves of the plant} ² In m ³ /h；

Step S3, taking a water flushing pressure p with a value of 1.3 times of a pump lift H, wherein the unit is mH ₂ O。

6. The method for configuring the flushing parameters of the dredge pump according to claim 5, wherein:

wherein the tangential flushing flow q has a value of q=0.075 n.D _{Leaves of the plant} ² 。