Vertical pump and urea synthesis plant

Patent metadata

Field	Value
Publication number	US-10704559-B2
Application number	US-201716325899-A
Country	US
Kind code	B2
Filing date	Nov 9, 2017
Priority date	Jan 10, 2017
Publication date	Jul 7, 2020
Grant date	Jul 7, 2020

Abstract

A vertical pump includes: a rotary shaft; multi-stage impellers; a casing accommodating the multi-stage impellers; a mechanical seal provided in a penetration part of the casing for the rotary shaft; a balance sleeve, the balance sleeve being positioned between a final stage impeller of the multi-stage impellers and the mechanical seal in the penetration part for the rotary shaft; an intermediate chamber provided between the rotary shaft and the casing and provided on an opposite side of the multi-stage impellers across the balance sleeve in an axial direction of the rotary shaft, the intermediate chamber communicating with an intermediate stage impeller among the multi-stage impellers; a low pressure chamber provided between the rotary shaft and the casing, the low pressure chamber communicating with a low pressure side compared to the intermediate chamber; and a partition wall part dividing the intermediate chamber and the low pressure chamber.

First claim

The invention claimed is:

1. A vertical pump, comprising:
a rotary shaft;
multi-stage impellers configured to rotate with the rotary shaft;
a casing accommodating the multi-stage impellers;
a mechanical seal provided in a penetration part of the casing for the rotary shaft;
a balance sleeve for at least partially balancing a thrust force of the rotary shaft, the balance sleeve being positioned between a final stage impeller of the multi-stage impellers and the mechanical seal in the penetration part for the rotary shaft;
an intermediate chamber provided between the rotary shaft and the casing and provided on an opposite side of the multi-stage impellers across the balance sleeve in an axial direction of the rotary shaft, the intermediate chamber communicating with an intermediate stage impeller among the multi-stage impellers;
a low pressure chamber provided between the rotary shaft and the casing and provided adjacent to the mechanical seal in the axial direction, the low pressure chamber communicating with a low pressure side compared to the intermediate chamber; and
a partition wall part dividing the intermediate chamber and the low pressure chamber.

2. The vertical pump according to claim 1 ,
wherein the mechanical seal includes:
a pair of stationary rings provided in the casing; and
a pair of rotary rings configured to be rotatable with the rotary shaft so as to slide with respect to the respective stationary rings, and

wherein the mechanical seal is a tandem mechanical seal in which the stationary rings and the rotary rings are alternately arranged in the axial direction.

3. The vertical pump according to claim 1 ,
wherein the casing includes:
an intermediate casing covering the multi-stage impellers;
an outer casing provided so as to cover the intermediate casing; and
a casing cover attached to the outer casing so as to seal an upper end opening of the outer casing and having the penetration part for the rotary shaft,

wherein the vertical pump further comprises:
a lower bearing supporting a low end part of the rotary shaft rotatably to the intermediate casing; and
an intermediate bearing supporting an intermediate part of the rotary shaft rotatably to the intermediate casing, and

wherein the intermediate chamber communicates with the intermediate stage impeller positioned above the lower bearing and below the intermediate bearing.

4. The vertical pump according to claim 1 ,
wherein the vertical pump is configured to pressurize liquid liquefied by compressing substance which is gas under normal temperature and atmospheric pressure.

5. The vertical pump according to claim 1 ,
wherein the casing includes:
an intermediate casing covering the multi-stage impellers;
an outer casing provided so as to cover the intermediate casing; and
a casing cover attached to the outer casing so as to seal an upper end opening of the outer casing and having the penetration part for the rotary shaft,

wherein a balance internal flow passage communicating with the intermediate chamber is formed in the casing cover, and
wherein the casing further includes a balance pipe provided between the intermediate casing and the outer casing so that the balance internal flow passage and the intermediate stage impeller communicate with each other.

6. The vertical pump according to claim 1 ,
wherein the casing includes:
an intermediate casing covering the multi-stage impellers;
an outer casing provided so as to cover the intermediate casing; and
a casing cover attached to the outer casing so as to seal an opening of the outer casing,

wherein the intermediate casing includes:
a plurality of first sections stacked in an axial direction of the vertical pump and provided so as to surround a plurality of impellers of a first group among the multi-stage impellers;
a plurality of second sections stacked in the axial direction and provided so as to surround a plurality of impellers of a second group among the multi-stage impellers; and
a fastening section provided between the plurality of first sections and the plurality of second sections in the axial direction, and

wherein the vertical pump further comprises:
at least one first tie bolt fixed to the fastening section at one end of the at least one first tie bolt and extending from the fastening section over a positional range occupied by the plurality of first sections in the axial direction; and
at least one second tie bolt fixed to the fastening section at one end of the at least one second tie bolt and extending from the fastening section over a positional range occupied by the plurality of second sections in the axial direction opposite to the first tie bolt.

7. The vertical pump according to claim 6 ,
wherein the plurality of impellers of the first group is provided downstream of the plurality of impellers of the second group, and
wherein the at least one first tie bolt has a larger diameter than the at least one second tie bolt.

8. The vertical pump according to claim 6 ,
wherein a plurality of the first tie bolts and a plurality of the second tie bolts are alternately arranged in a circumferential direction of the intermediate casing.

9. The vertical pump according to claim 6 , further comprising a bearing for rotatably supporting the rotary shaft, the bearing being provided between the fastening section and the rotary shaft.

10. The vertical pump according to claim 6 ,
wherein the intermediate casing includes:
a suction bell section located on a side opposite to the casing cover across the multi-stage impellers in the axial direction, the suction bell section having a suction bell for introducing liquid to a first stage impeller of the multi-stage impellers,

wherein the other end of the at least one first tie bolt is fixed to the casing cover, and
wherein the other end of the at least one second tie bolt is fixed to the suction bell section.

11. The vertical pump according to claim 6 ,
wherein the intermediate chamber is provided between the rotary shaft and the casing and provided on an opposite side of the multi-stage impellers across the balance sleeve in an axial direction of the rotary shaft,
wherein the vertical pump further comprises a balance pipe directed from the casing cover to one section of the first sections or the second sections and provided between the intermediate casing and the outer casing so that the balance internal flow passage and the intermediate stage impeller communicate with each other, and
wherein the balance pipe is arranged so as to be offset in a radial direction or a circumferential direction of the intermediate casing with respect to at least one of the first tie bolt or the second tie bolt in a plan view.

12. The vertical pump according to claim 11 ,
wherein the intermediate casing includes a suction bell section located on a side opposite to the casing cover across the multi-stage impellers in the axial direction, the suction bell section having a suction bell for introducing liquid to a first stage impeller of the multi-stage impellers,
wherein the other end of the at least one first tie bolt is fixed to the casing cover,
wherein the other end of the at least one second tie bolt is fixed to the suction bell section, and
wherein the balance pipe is arranged so as to be offset in the radial direction with respect to any one of the at least one first tie bolt and connects with any one of the second sections through between a pair of second tie bolts which are adjacent to each other in the circumferential direction.

13. The vertical pump according to claim 6 ,
wherein the multi-stage impellers include impellers i

Assignees

• Mitsubishi Heavy Ind Ltd

Inventors

• Funakoshi Hiroshi
• Ueda Yasushi
• Maeda Akio
• Koyama Yasuhiro
• Fukuta Hidetoshi
• Ikunami Masahide

Classifications

• F04D13/00

  Pumping installations or systems (controlling F04D15/00) · CPC title

• F04D29/086

  especially adapted for liquid pumps · CPC title

• F04D29/426

  especially adapted for liquid pumps · CPC title

• F04D1/066

  the casing consisting of a plurality of annuli bolted together · CPC title

• F04D29/4293

  Details of fluid inlet or outlet · CPC title