CN105508292A - Semi-open type vortex pump impeller structure design method - Google Patents

Abstract

The invention relates to a semi-open type vortex pump impeller structure design method. In the method, design formulas of an impeller inlet diameter, an impeller outlet diameter, a blade outlet width, an impeller back cover plate groove width, a back blade thickness, a back blade width and a blade number are given. A vortex pump, designed according to the design method, can havea vortex pump impeller structure improved; when a blade is highly worn, only the blade is replaced, so that the resource waste is reduced; and as a special structure is equivalent to one with an additionally arranged back blade, the axial force can be well balanced.

Description

A kind of semi-open type vortex pump impeller construction design method

Technical field

The present invention relates to a kind of semi-open type vortex pump impeller construction design method, particularly relate to a kind of detachable block torque flow pump half-opened impeller construction design method.

Background technique

Along with the progress of science and technology, pump is not only used for carrying various liquid, also has to carry various material (comprising solid).Torque flow pump is generally used for carrying impure medium, and structure forward spin flow pump impeller is shunk back to without room after phyllocyst, and blade many employings prismatic blade form.Unique structure makes to have not blocking property when its large particle and long fibre dirt, therefore is also called Non-blinding pump.Because its inside exists through stream and circular flow simultaneously, cause very large hydraulic loss.Therefore its disadvantage to be pump efficiency on the low side, general η≤50%.Because its conveying is containing solid particle, after the long period is run, blade surface can be worn, and badly influences the normal work of pump.But relative vane, wheel hub and back shroud place wear and tear less, still can normally use.If now entirety changes the outfit impeller, larger waste can be caused.

Summary of the invention

For solving the problem, the invention provides a kind of semi-open type vortex pump impeller construction design method.By changing the defining method of vortex pump impeller several important design parameter, thus improve vortex pump impeller structure, occur blade comparatively galling time only change blade, reduce the wasting of resources, because special construction is equivalent to additional back blade, can balancing axial thrust very well.

Realize the design method that above-mentioned purpose adopts:

1. impeller inlet diameter

Impeller inlet diameter formula

$D_j=\sqrt{K_0{(Q/n)}^{0.71}+{(M_n/0.2\[\mathrm{\τ}\])}^{0.71}}$

In formula, D _j-vortex pump impeller external diameter, mm;

K ₀-impeller inlet equivalent diameter coefficient, K ₀value 16 ~ 25;

M _n-torque flow pump moment of torsion, Nm;

Q-torque flow pump flow, m ³/ s;

N-torque flow pump rotating speed, r/min;

[τ]-pump shaft material allowable shear stress, Pa;

2. impeller outlet diameter

Blade exit diameter formula

$D_2=0.92{n_s}^{0.4595}\sqrt[3]{\frac{Q}{n}}+d_h$

In formula, D ₂-blade exit diameter, mm;

N _s-torque flow pump specific speed;

Q-torque flow pump flow, m ³/ s;

N-torque flow pump rotating speed, r/min;

D _h-torque flow pump back shroud thickness, mm;

3. blade exit width

Blade exit width calculation formula

$b_2=0.14{n_n}^{0.825}\sqrt[3]{\frac{Q}{n}}$

In formula, b ₂-blade exit width, mm;

N _s-torque flow pump specific speed;

Q-torque flow pump flow, m ³/ s;

N-torque flow pump rotating speed, r/min;

4. the number of blade

Number of blade defining method

z＝3～5

In formula:

Z-number of blade;

5. blades installation mode and key dimension

Back shroud of impeller has the groove with number of blade equal number, blade is inserted wherein also fastening by flat key.What blade hub positions was positioned at the back shroud back side is equivalent to additional back blade for balancing axial thrust.

b _h＝δ+0.5e _v

t＝(0.2～0.3)b ₂

s-t<0.5e _v

φ＝b _h+20

Flat key choice criteria part, flat key thickness must not be greater than 0.5 times of back shroud thickness, and length is about length of blade 0.3 times.

In formula, b _h-torque flow pump back shroud groove width, mm;

δ-vane thickness, mm;

T-blade back blade place thickness, mm;

The gap of s-between back blade and pump chamber, mm;

Φ-back blade width, mm;

E _vsolid phase particles average diameter in-torque flow pump fed sheet of a media, mm;

The invention has the beneficial effects as follows: by changing the defining method of the several important design parameter of vortex pump impeller, thus improve vortex pump impeller structure, occur blade comparatively galling time only change blade, reduce the wasting of resources, because special construction is equivalent to additional back blade, can fine balancing axial thrust.

Accompanying drawing explanation

Fig. 1 is the paddle wheel plane projection drawing of one embodiment of the invention

Fig. 2 is the impeller cross-sectional view of one embodiment of the invention

In figure: 1. impeller inlet diameter, 2. impeller outlet diameter, 3. blade exit width, 4. back shroud of impeller groove width, 5. back shroud of impeller thickness, 6. vane thickness, 7. back blade thickness, 8. back blade width, 9. flat key width of keyway, 10. flat key keyway length.

Embodiment

Fig. 1 and Fig. 2 combination defines impeller shape and the installation of torque flow pump.It improves vortex pump impeller structure, occur blade comparatively galling time only change blade, reduce the wasting of resources, because special construction is equivalent to additional back blade, can fine balancing axial thrust.The present invention by following relation determine impeller inlet diameter (1). impeller outlet diameter (2), blade exit width (3), back shroud of impeller groove width (4), back blade thickness (7), back blade width (8) and the number of blade.

$D_j=\sqrt{K_0{(Q/n)}^{0.71}+{(M_n/0.2\&lsqb;\mathrm{\&tau;}\&rsqb;)}^{0.71}};$

$D_2=0.92{n_s}^{0.4595}\sqrt[3]{\frac{Q}{n}}+d_h;$

$b_2=0.14{n_n}^{0.825}\sqrt[3]{\frac{Q}{n}};$

z＝3～5；

b _h＝δ+0.5e _v；

t＝(0.2～0.3)b ₂；

s-t<0.5e _v；

φ＝b _h+20；

Above, that makes with reference to embodiment for patent of the present invention illustrates, but the present invention is not limited to above-described embodiment, also comprises other embodiments in concept of the present invention or variation.

Claims (5)

1. a semi-open type vortex pump impeller construction design method, is characterized in that: vortex pump impeller geometric parameter is applicable to following relation:

In formula, D _j-vortex pump impeller external diameter, mm;

K ₀-impeller inlet equivalent diameter coefficient, K ₀value 16 ~ 25;

M _n-torque flow pump moment of torsion, Nm;

Q-torque flow pump flow, m ³/ s;

N-torque flow pump rotating speed, r/min;

[τ]-pump shaft material allowable shear stress, Pa.

2. a kind of semi-open type vortex pump impeller construction design method as claimed in claim 1, is characterized in that: vortex pump impeller geometric parameter is applicable to following relation:

In formula, D ₂-blade exit diameter, mm;

N _s-torque flow pump specific speed;

Q-torque flow pump flow, m ³/ s;

N-torque flow pump rotating speed, r/min;

D _h-torque flow pump back shroud thickness, mm.

3. a kind of semi-open type vortex pump impeller construction design method as claimed in claim 1, is characterized in that: vortex pump impeller geometric parameter is applicable to following relation:

In formula, b ₂-blade exit width, mm;

N _s-torque flow pump specific speed;

Q-torque flow pump flow, m ³/ s;

N-torque flow pump rotating speed, r/min.

4. a kind of semi-open type vortex pump impeller construction design method as claimed in claim 1, is characterized in that: the vortex pump impeller number of blade meets following relation:

z＝3～5

In formula:

Z-number of blade.

5. a kind of semi-open type vortex pump impeller construction design method as claimed in claim 1, is characterized in that: back shroud of impeller has the groove with number of blade equal number, is inserted by blade wherein also fastening by flat key; What blade hub positions was positioned at the back shroud back side is equivalent to additional back blade for balancing axial thrust;

b _h＝δ+0.5e _v

t＝(0.2～0.3)b ₂

s-t<0.5e _v

φ＝b _h+20

Flat key choice criteria part, flat key thickness must not be greater than 0.5 times of back shroud thickness, and length is about length of blade 0.3 times.

In formula, b _h-torque flow pump back shroud groove width, mm;

δ-vane thickness, mm;

T-blade back blade place thickness, mm;

The gap of s-between back blade and pump chamber, mm;

Φ-back blade width, mm;

E _vsolid phase particles average diameter in-torque flow pump fed sheet of a media, mm.