CN101457773A - Uniaxial paralleling centrifugal pump for simultaneously conveying double mediums - Google Patents

Abstract

The invention relates to a single-shaft parallel centrifugal pump which simultaneously transports two mediums. The current transport of two mediums employs two centrifugal pumps connected in parallel and the precision is not sufficient. A front pressing chamber and a back pressing chamber are arranged in the body of the pump; two impellers are respectively arranged in the front pressing chamber and the back pressing chamber. The two ends of the body of the pump are respectively provided with a front pump cover and a back pump cover; the front pump cover and the back pump cover are respectively provided with a liquid inlet. A main shaft penetrates the front pump cover, the body of the pump and the back pump cover; the two impellers are respectively and fixedly connected with the main shaft; a seal piece is arranged between the two impellers; the front pressing chamber and the back pressing chamber are isolated by the seal piece. One end of the front pressing chamber of the body of the pump and one end of the back pressing chamber of the body of the pump are respectively communicated with a front suction chamber and a back suction chamber; the other ends are respectively communicated with the two liquid outlets; the front suction chamber and the back suction chamber are respectively communicated with two liquid inlets. The single-shaft parallel centrifugal pump can realize that two mediums can respectively pass through the two independent impellers from the two liquid inlets, respectively work and flow out from the two pressing chambers to realize the transportation of two different mediums. The single-shaft parallel centrifugal pump has the advantages of compact structure, small volume, and low cost.

Description

The uniaxial paralleling centrifugal pump that two media are carried simultaneously

Technical field

The invention belongs to field of mechanical technique, relate to transfer pump, specifically relate to the uniaxial paralleling centrifugal pump that a kind of pair of medium carried simultaneously, promptly only just can carry two kinds of different mediums simultaneously with a centrifugal pump.

Background technique

In the existing centrifugal pump, single entry pump has only an import, an outlet.Double suction pump has two imports, but has only an outlet.Therefore, carry when a centrifugal pump can not be realized two media, can only carry a kind of medium.But, may need two kinds of different mediums under certain pressure and flow, to react in fields such as chemical industry, oil and food.What adopt at present is the mode of two centrifugal pumps in parallel.But there is the inconsistent shortcoming of transient speed in two main shafts of parallel centrifugal pumps.When if chemical reaction is had relatively high expectations to two kinds of reactant mixed-precisions, two centrifugal pumps in parallel do not reach requirement.

For double suction pump, its impeller is actually by two impellers and welds together an integral body that constitutes back-to-back, and medium enters suction chamber from two imports respectively, flows out from a pumping chamber behind impeller.If carry two kinds of different media with double suction pump, then liquid can mix mutually at pumping chamber, and this is obviously improper.In order on a centrifugal pump, to realize carrying in two kinds of different mediums, just require a centrifugal pump to have two outlets and two imports, two overlap independently flow passage components.

Summary of the invention

The purpose of this invention is to provide a kind of single shaft centrifugal pump that can realize that two media are carried simultaneously.

The present invention includes the pump housing, the pump housing is provided with two liquid outlets, delivery chamber and back delivery chamber before being symmetrically arranged with in the pump housing, and two impellers are separately positioned in preceding delivery chamber and the back delivery chamber.Pump housing two ends are respectively arranged with the front pump cover and the rear pump cover of hollow structure, respectively are provided with a liquid entering hole on front pump cover and the rear pump cover, and the inner space of front pump cover is preceding suction chamber, and the inner space of rear pump cover is the back suction chamber.Two liquid entering holes are horizontally set on the same side of the pump housing, and perpendicular to main shaft.Main shaft passes front pump cover, the pump housing and rear pump cover setting successively.The front pump cover end is set with front cover, the rear pump cover end is set with rear end cover, and an end of main shaft is connected with rear end cover by rear bearing, and the other end passes front cover and is connected by coupling with motor, and main shaft is connected with front cover by fore bearing.Two impellers are fixedlyed connected with main shaft respectively, are provided with Sealing between two impellers, and preceding delivery chamber and back delivery chamber are isolated by Sealing, and Sealing is nested with on main shaft.One end of the preceding delivery chamber of the pump housing is communicated with preceding suction chamber, an end of back delivery chamber is communicated with the back suction chamber, before the other end of delivery chamber and back delivery chamber be communicated with corresponding two liquid outlets respectively, preceding suction chamber and back suction chamber are communicated with corresponding two liquid entering holes respectively.

The external diameter ratio of described two impellers is 1:0.9～1.1.

Described Sealing is packing seal structure or mechanical seal structure.

The present invention has two delivery chambers, and two impellers also are to be separately fixed on the main shaft, can realize that two different media flow out from two delivery chambers through the work done of two independent impellers difference from two liquid entering holes respectively, thereby has realized the conveying of two kinds of different mediums.Overall structure of the present invention adopts symmetric design, and two impellers " back-to-back " form is installed in the middle of the main shaft, separates by Sealing, and the mode of " back-to-back " can effectively be eliminated axial force.Compact structure of the present invention has reduced the volume of centrifugal pump, has alleviated cost, need to can be applicable to two kinds of different mediums to mix under certain pressure and flow or the association areas such as chemical industry, oil and food of chemical reaction.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 be among Fig. 1 A-A to schematic cross-section;

Fig. 3 be among Fig. 1 B-B to schematic cross-section.

Embodiment

Shown in Fig. 1,2 and 3, the uniaxial paralleling centrifugal pump that two media are carried simultaneously comprises the pump housing 13, the pump housing is provided with two liquid outlets 14, and delivery chamber 15 and back 12, two impellers 5 of delivery chamber and 7 are separately positioned in preceding delivery chamber 15 and the back delivery chamber 12 before being symmetrically arranged with in the pump housing.The pump housing 13 two ends are respectively arranged with the front pump cover 16 and the rear pump cover 11 of hollow structure, respectively are provided with a liquid entering hole 18 on front pump cover 16 and the rear pump cover 11, and the inner space of front pump cover 16 is preceding suction chamber 4, and the inner space of rear pump cover 11 is a back suction chamber 8.Two liquid entering holes 18 are horizontally set on the same side of the pump housing 13, and perpendicular to main shaft 3.Main shaft 3 passes front pump cover 16, the pump housing 13 and rear pump cover 11 successively and is provided with.Front pump cover 16 ends are set with front cover 17, rear pump cover 11 ends are set with rear end cover 10, one end of main shaft 3 is connected with rear end cover 10 by rear bearing 9, the other end passes front cover 17 and is connected by coupling 1 with motor, and main shaft 3 is connected with front cover 17 by fore bearing 2.Two impellers 5 are fixedlyed connected with main shaft 3 respectively with 7, are provided with Sealing 6 between two impellers, and preceding delivery chamber 15 and back delivery chamber 12 are isolated by Sealing 6, and Sealing 6 is nested with on main shaft 3.One end of the preceding delivery chamber 15 of the pump housing 13 is communicated with preceding suction chamber 4, an end of back delivery chamber 12 is communicated with back suction chamber 8, before the other end of delivery chamber 15 and back delivery chamber 12 be communicated with corresponding two liquid outlets 14 respectively, preceding suction chamber 4 and back suction chamber 8 are communicated with corresponding two liquid entering holes 18 respectively.

During pump work, suction chamber 4 and back suction chamber 8 before two kinds of different media are entered by two liquid entering holes respectively, two impeller rotations on the motor rotating band moving axis, liquid obtains the pressure energy through impeller 5 and the acting of 7 centrifugal force, respectively two kinds of different media is extruded from two liquid outlets 14 through forward and backward delivery chamber.The pump overall structure adopts the symmetric form design, and outward appearance is short and sweet, is easy to installation and maintenance.Impeller adopts back-to-back form can also eliminate the axial force and the radial force of impeller, has improved the reliability of pump operation.

In the single shaft characteristic of centrifugal pump design process that two media are carried simultaneously, design speed is identical, and the rated lift of the design discharge of two liquid entering holes 18 and liquid outlet 14 can be determined according to designing requirement.The flow passage components size of design is the same if the two media design parameter is identical; If two media design parameter difference is coordinated according to impeller outer diameter, two impeller outer diameter sizes are differed be controlled within 10%.Meeting design requirement down, make two impeller outer diameters differ as much as possible little, perhaps make two impeller outer diameters equate that the axial force between them can suitably be offset or eliminate like this, thereby has improved the reliability of pump operation.

The formula of the outer diameter D 2 of impeller:

$D_2=19.2{\left(\frac{n_s}{100}\right)}^{1/6}\frac{\sqrt{2\mathrm{gH}}}{n}$ $n_s=\frac{3.65\×n\×\sqrt{Q}}{H^{\frac{3}{4}}}$

In the formula: n-centrifugal pump rotating speed, r/min; H-lift, m; Q-flow, m ³/ s; Ns-specific speed.

By the formula of impeller outer diameter as can be known, the external diameter of impeller is relevant with H, n, Q.When the design discharge of two media and lift were inconsistent, the external diameter of two designed impellers was just different.In order effectively to offset axial force, so the ratio δ of absolute value and impeller outer diameter of difference that requires two impeller outer diameters is less than 10%.That is:

$\mathrm{\δ}=\frac{|D_{21}-D_{22}|}{D_{21}}\≤10\%,$ D in the formula ₂₁---the external diameter of impeller 5; D ₂₂---the external diameter of impeller 7.

Claims (3)

1, the uniaxial paralleling centrifugal pump carried simultaneously of two media comprises the pump housing, and it is characterized in that: the pump housing is provided with two liquid outlets, and delivery chamber and back delivery chamber before being symmetrically arranged with in the pump housing are before two impellers are separately positioned in delivery chamber and the back delivery chamber; Pump housing two ends are respectively arranged with the front pump cover and the rear pump cover of hollow structure, respectively be provided with a liquid entering hole on front pump cover and the rear pump cover, the inner space of front pump cover is preceding suction chamber, the inner space of rear pump cover is the back suction chamber, two liquid entering holes are horizontally set on the same side of the pump housing, and perpendicular to main shaft; Main shaft passes front pump cover, the pump housing and rear pump cover setting successively, the front pump cover end is set with front cover, the rear pump cover end is set with rear end cover, one end of main shaft is connected with rear end cover by rear bearing, the other end passes front cover and is connected by coupling with motor, and main shaft is connected with front cover by fore bearing; Two impellers are fixedlyed connected with main shaft respectively, are provided with Sealing between two impellers, and preceding delivery chamber and back delivery chamber are isolated by Sealing, and Sealing is nested with on main shaft; One end of the preceding delivery chamber of the pump housing is communicated with preceding suction chamber, an end of back delivery chamber is communicated with the back suction chamber, before the other end of delivery chamber and back delivery chamber be communicated with corresponding two liquid outlets respectively, preceding suction chamber and back suction chamber are communicated with corresponding two liquid entering holes respectively.

2, as claimed in claim 1 pair of uniaxial paralleling centrifugal pump that medium is carried simultaneously is characterized in that: the external diameter ratio of described two impellers is 1:0.9～1.1.

3, as claimed in claim 1 pair of uniaxial paralleling centrifugal pump that medium is carried simultaneously is characterized in that: described Sealing is packing seal structure or mechanical seal structure.

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