Pulsation damper suitable for hygienic processing lines
09587779 ยท 2017-03-07
Assignee
Inventors
Cpc classification
F16L55/04
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16L55/0279
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
F16L55/04
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F16L55/027
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Abstract
A pulsation damper configured to reduce pressure variations in a pipe system. The pulsation damper comprises a first pipe section and a second pipe section. The first pipe section is at least partly placed inside the second pipe section such that a product flow can flow through the first pipe section and then through a space formed between the first pipe section and the second pipe section. Due to the increased cross sectional area of the second pipe section pressure variations can be damped efficiently.
Claims
1. A pulsation damper configured to reduce pressure variations in a pipe system, said pulsation damper comprising a first pipe section and a second pipe section, said first pipe section being at least partly placed inside said second pipe section, such that a product can flow through said first pipe section and through a space formed between said first pipe section and said second pipe section, and the first pipe section possessing a cross-sectional shape enclosing a volume and being made of an elastic material so that when pressure inside the first pipe section increases from a lower pressure state to a higher pressure state, the cross-sectional shape of the first pipe section changes to increase the volume in the first pipe section and thereby damp pulsation.
2. The pulsation damper according to claim 1, wherein said second pipe section is connected to a piston pump arrangement.
3. The pulsation damper according to claim 1, wherein said second pipe section has a non-circular cross section in at least one point.
4. The pulsation damper according to claim 3, wherein said non-circular cross section has an elliptical cross section.
5. The pulsation damper according to claim 1, wherein said first pipe section has a non-circular cross section in at least one point.
6. The pulsation damper according to claim 1, wherein a first cross sectional area being a cross sectional area of said first pipe section is essentially the same as a second cross sectional area being a cross sectional area of said space formed between said first pipe section and said second pipe section.
7. The pulsation damper according to claim 1, further comprising a volume adding element placed in said first pipe section.
8. The pulsation damper according to claim 7, wherein a third cross sectional area being a cross sectional area of a space formed between said first pipe section and said volume adding element is essentially the same as a second cross sectional area being a cross sectional area of said space formed between said first pipe section and said second pipe section.
9. The pulsation damper according to claim 1, wherein said first pipe section is arranged to enter in a mid section of said second pipe section.
10. The pulsation damper according to claim 1, further comprising a third pipe section, wherein said second pipe section is at least partly placed inside said third pipe section.
11. The pulsation damper according to claim 10, wherein said third pipe section has a non-circular cross section in at least one point.
12. The pulsation damper according to claim 10, wherein said first pipe section enters said third pipe section in an end section.
13. A pulsation damper system comprising a first pulsation damper according to claim 1, said first pulsation damper being connected to an outlet of a piston pump arrangement, and a second pulsation damper comprising a second pulsation damper pipe section, said first pulsation damper being placed inside said second pulsation damper pipe section, and said second pulsation damper pipe section being connected to an inlet of said piston pump arrangement.
14. A processing line comprising a piston pump, and a pulsation damper according to claim 1.
15. A homogenizer comprising a piston pump, a homogenizing device, and a pulsation damper according to claim 1.
16. A food processing line comprising a homogenizer according to claim 15.
17. The pulsation damper according to claim 1, wherein said second pipe section is connected to a homogenizer.
18. A pulsation damper configured to reduce pressure variations in a pipe system, the pulsation damper comprising a first pipe section and a second pipe section, the first pipe section being at least partly positioned inside the second pipe section to permit product to flow through the first pipe section and through a space formed between the first pipe section and the second pipe section, the space possessing a volume, the first pipe section possessing a cross-sectional shape enclosing a first volume and being made of an elastic material so that when pressure inside the first pipe section increases from a lower pressure state to a higher pressure state, the cross-sectional shape of the first pipe section changes to increase the first volume in the first pipe section and thereby damp pulsation, and the second pipe section possessing a cross-sectional shape and being made of an elastic material so that when pressure in the space between the first pipe section and the second pipe section increases from a lower pressure state to a higher pressure state, the cross-sectional shape of the second pipe section changes to increase the volume of the space between the first pipe section and the second pipe section and thereby damp pulsation.
19. A pulsation damper configured to reduce pressure variations in a pipe system, the pulsation damper comprising: a first pipe section and a second pipe section; the first pipe section being at least partly inside the second pipe section to permit a product to flow through the first pipe section and through a space formed between the first pipe section and the second pipe section; and at least one of the first and second pipe sections possessing a non-circular elliptical cross-sectional shape and being made of an elastic material so that when pressure inside the at least one of the first and second pipe sections increases from a lower pressure state to a higher pressure state, the cross-sectional shape of the at least one of the first and second pipe sections becomes less elliptical to damp pulsation.
20. The pulsation damper according to claim 19, wherein the at least one of the first and second pipe sections is the first pipe section, and the second pipe section possesses a non-circular elliptical cross-sectional shape and is made of an elastic material so that when pressure inside the space formed between the first pipe section and the second pipe section increases from a lower pressure state to a higher pressure state, the cross-sectional shape of the second pipe section becomes less elliptical to damp pulsation.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) The above, as well as additional objects, features and advantages of the present invention, will be better understood through the following illustrative and non-limiting detailed description of preferred embodiments of the present invention, with reference to the appended drawings, wherein:
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DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
(17)
(18) In this example, the high pressure pump is a piston pump driven by a main drive motor 101 connected via a belt transmission 102 and a gearbox 103 to a crankshaft placed in a crankcase 104. By using the crankshaft the rotary motion is converted to a reciprocating motion driving pump pistons 105 back and forth. Today, it is common to have three to five pump pistons, but both fewer and more pistons may be used as well.
(19) The pump pistons 105 run in cavities formed in a pump block 106 made to withstand the high pressure created by the pump pistons. Today it is common to increase the pressure from 300 kPa (3 bar) to about 10-25 MPa (100-250 bar), but higher pressures can be used as well.
(20) Through cavities in the pump block 106 the product enters a first homogenizing device 107 and thereafter, in many cases, a second homogenizing device 108. As described above, by forcing the product through one or several gaps the properties of the product can be changed.
(21) The reciprocating motion of the pump pistons 105 creates pulsations. To reduce the pulsations it is common practice today to place an inlet damper 109 on an inlet of the homogenizer. Further, in order to reduce vibrations and noise it is common practice to place an outlet damper 110 on an outlet.
(22) The inlet damper 109 and the outlet damper 110 may as illustrated in
(23)
(24) The drawback of having vertical pipes closed in the upper ends as dampers is that they are difficult to clean by using common cleaning in place (CIP) technology. Therefore, in order to clean these they are usually dismounted and cleaned manually. This is both labour intensive and reduces the uptime for the entire line, which of course is a disadvantage.
(25) In order to solve this problem different solutions with by-pass valves have been developed. The main idea with these solutions are to have one mode for production when the upper ends are closed, for instance by closing one or several valves, and another mode during cleaning when the valves are open such that water and cleaning agents can flow through the pipes.
(26)
(27) In this example, for both the inlet damper 302a and the outlet damper 302b, a first connection pipe 304a, 304b, which can be a stainless steel pipe with a circular cross section, is attached to a first transition section 306a, 306b in turn connected to a damper section 308a, 308b with an elliptical cross section. The damper section 308a, 308b can in turn be connected to a second transition section 310a, 310b, in turn connected to a second connection pipe 312a, 312b, which also can be a stainless steel pipe with a circular cross section. An advantage of having the first connection pipe 304a, 304b and the second connection pipe 312a, 312b provided with a circular cross section is that today's standard connections can be used.
(28) As illustrated in
(29) By having elliptical damper sections 308a, 308b made in an elastic material, such as stainless steel, the elliptical damper sections may change from a low pressure state with an elliptical cross section, as illustrated by example in
(30) As stated above, the cross sectional area of the damper sections 308a, 308b should not differ too much from the cross sectional area of the connection pipes in order to provide for efficient cleaning in place (CIP). It has however been realized that by only having the damper section capable of compensating for a small volume, the pulsations can be significantly reduced. Therefore, due to the small volume required for damping pulsations, it has been realized that elliptical damper sections 308a, 308b that can reduce pulsations efficiently and that can be cleaned efficiently is possible to achieve.
(31) As illustrated in
(32) When a pulsation, i.e. pressure peak, enters the damper section, the damper section can due to the elasticity of the stainless steel, or other elastic material used for the damper section, force the cross section to go towards a more circular cross section 400b, as illustrated in
(33) In order to provide for a long lasting damper section, the damper section can be made as an elliptical element, for instance by using hydroforming.
(34) Further, in order to provide for an efficient damping, a long lasting damper section or that the amount of material used is kept at a low level the thickness of the damper section may differ between different parts of the damper section, both around the periphery, but also over a length of the damper section.
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(37) In the example illustrated in
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(39) As illustrated in
(40) In order to keep the same velocity, or at least a similar velocity, of product flow in the first pipe section 704 as in the space between the first pipe section 704 and the second pipe section 706, the pulsation damper 702 may be designed such that a first cross sectional area 708 of the first pipe section 704 is equal to a second cross sectional area 710 of the space formed between the first pipe section 704 and the second pipe section 706.
(41) An effect of having the first pipe section 704 placed inside the second pipe section 706 may be that pulsations may be damped due to the elasticity of the first pipe section 704. More particularly, as an example, a pulsation forming a lowered pressure in the space between the first and second pipe section and an increased pressure in the first pipe section may be damped due to that the cross sectional area 708 of the first pipe section 704 is increased. A further example is that a pulsation forming an increased pressure in the space between the first and second pipe section sections and a lowered pressure in the first pipe section may be damped due to that the cross sectional area 708 of the first pipe section is decreased. Further, in combination or on its own, the second pipe section may flex outwards such that the second cross sectional area 710 is increased. The second pipe section may be made of an elastic material and may have an elliptical cross section.
(42) Further, even though not illustrated, the pulsation damper 702 may alternatively be placed on an outlet of the homogenizer 700. Still an alternative is to have pulsation dampers placed on both the inlet and the outlet.
(43) When having the pulsation damper 702 placed on the outlet of the homogenizer, an option is to have the first pipe 704 connected to the homogenizer 700, instead of the second pipe 706 as illustrated.
(44) Further, as an option, a volume adding element 712 may be introduced in the first section 704 as illustrated. An advantage of having the volume adding element is that cross sectional areas of the first pipe section 704 and the second pipe section 706 may be larger, resulting in improved damping efficiency.
(45)
(46) The pulsation damper 802 can comprise a first pipe section 804, a second pipe section 806 and a third pipe section 808. As illustrated, the first pipe section 804 is partly placed inside the second pipe section 806, which in turn is placed inside the third pipe section 808. The second pipe section 806 is closed in one end providing for that the product is fed from the first pipe section 804 to a space formed between the first pipe section 804 and the second pipe section 806. The third pipe section 808 can be closed around the first pipe section in one end and connected to the homogenizer 800 in the other end, thereby providing for that the product is fed from the space between the first pipe section 804 and the second pipe section 806 to a space between the second pipe section 806 and the third pipe section 808 and into the homogenizer. In the illustrated example the third pipe section 808 is connected to an inlet of the homogenizer, but it can be connected to the outlet as well.
(47) In order to keep the first pipe section 804 in position a first supporting element 810, herein illustrated as one supporting element, but several supporting elements may be used as well, may be attached to the first pipe section 804 and the second pipe section 806. Further, in a similar way, in order to keep the second pipe section 806 in position, one or several second supporting elements 812a, 812b may be attached to the second pipe section 806 and the third pipe section 808. The number of supporting elements, how the supporting elements are placed and the design of the supporting elements may vary for different configurations and the first supporting element and the second supporting elements are therefore only to be seen as one example of many alternatives.
(48) Further, since the third pipe section 808 is attached to the homogenizer the second supporting elements 812a, 812b are to be considered as optional.
(49) In order to keep the same velocity, or at least a similar velocity, of product flow in the first pipe section 804 as in the space between the first pipe section 804 and the second pipe section 806, the pulsation damper 802 may be designed such that a first cross sectional area 814 of the first pipe section 804 is equal to a second cross sectional area 816 of the space formed between the first pipe section 804 and the second pipe section 806. Further, a third cross sectional area 818 of a space formed between the second pipe section 806 and the third pipe section 808 may be designed such that this is equal to the first cross sectional area 814 and the second cross sectional area 816.
(50) As described above with reference to the example illustrated in
(51) Since the cross sectional area of an outer pipe section, e.g. the second pipe section 706 in
(52) In the examples illustrated in
(53) Further, in a corresponding manner, pulsation dampers having four or more pipe sections are possible as well.
(54)
(55) For illustrative purposes, different pressure at a certain point of time in the pulsation damper 900 are depicted by circles. A region 906 inside the first pipe section 902 has a low pressure compared to a region 908a, 1008b (surrounding the first pipe section) having a high pressure. In order to compensate for the high pressure in region 908a, 908b the second pipe section 904 flex outwards thereby increasing a cross sectional area of the second pipe section 904 with the effect that the pulsation is damped.
(56) In order to have an improved damping effect the second pipe section may be elliptical, as illustrated in
(57) By having a pipe in pipe solution a diameter of the second pipe section 904 may be larger than a diameter of the damper sections 308a, 308b illustrated in
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(59)
(60) Similar to the pulsation damper illustrated in
(61) As illustrated, the first pipe section 1104, the second pipe section 1106 and the third pipe section 1108 may be connected to an outlet of the homogenizer 1100 and the fourth pipe section may be connected to an inlet of the homogenizer 1100.
(62) In order to keep the first pipe section 1104, the second pipe section 1106 and the third pipe section 1108 in position supporting element 1112 may be used.
(63) As illustrated in
(64) Further, in order to keep the same velocity, or at least a similar velocity, of product flow in the first pipe section 1104 as in the space between the first pipe section 1104 and the second pipe section 1106, the pulsation damper 1102 may be designed such that a first cross sectional area 1114 of the first pipe section 1104 is equal to a second cross sectional area 1116 of the space formed between the first pipe section 1104 and the second pipe section 1106. Further, a third cross sectional area 1118 of a space formed between the second pipe section 1106 and the third pipe section 1108 may be designed such that this is equal to the first cross sectional area 1114 and the second cross sectional area 1116. In addition, a fourth cross sectional area 1120 of a space between the third pipe section 1108 and a fourth pipe section 1110 may be designed such that this is equal to the first cross sectional area 1114, the second cross sectional area 1116 and the third cross sectional area 1118.
(65) Further, though not illustrated, the idea of connecting the inlet and the outlet of the homogenizer may be used also for the damper solution illustrated in
(66) Further, although homogenizers comprising piston pumps are used as examples herein, the pulsation dampers can be used for any piece of equipment forming pulsations, such as roll fed filling machines using sealing jaws for transversal sealing marketed by Tetra Pak as Tetra Brik filling machines.
(67) The invention has mainly been described above with reference to a few embodiments. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope of the invention, as defined by the appended patent claims.