JP7291935B2 - Fluid transfer system - Google Patents

Description

Article 30, Paragraph 2 of the Patent Act applies Published at the 2018 International Food Industry Exhibition held at Tokyo Big Sight on June 12, 2018

TECHNICAL FIELD The present invention relates to a fluid transport system that exhibits a high defoaming ability and transports a viscous fluid, which is an object to be transported, even if the fluid has a relatively low viscosity.

2. Description of the Related Art Conventionally, as a twin-screw pump used in this type of fluid transport system, one described in Patent Document 1 below is known. The twin screw pump described in the document is equipped with a degassing pump, and as shown in FIGS. Between the tip surfaces 7B, 7B of 7a, 7b and the inner peripheral surface 2A of the pump casing 2, gaps G, H are formed, respectively, through which a gas such as air can pass but the viscous fluid Q cannot pass. In this pump, the viscous fluid Q is transferred while discharging the gas in the viscous fluid Q to the outside by driving the degassing device 27 connected to the gas outlet 20 of the pump casing 2. Although it is a positive displacement pump having a pair of non-contact pump screws 7a and 7b, it has the function of discharging gas from the viscous fluid Q and conveying it. A pump casing 2 of this pump is arranged with its axis directed in the horizontal direction.

JP 2015-55179 A

By the way, the twin-screw pump described in Patent Document 2 described above has the advantage of removing and conveying gas with high efficiency for relatively high-viscosity viscous fluid with low fluidity. However, since the pump casing of the twin-screw pump is arranged horizontally, the air bubbles separated from the viscous fluid being conveyed in the pump casing rise to the position below the ceiling in the pump casing, but the position below the ceiling does not reach the position below the ceiling. It is widely scattered in the front-rear direction. For this reason, there is a risk that air bubbles present near the viscous fluid discharge port may be carried out together with the viscous fluid, increasing the gas content of the viscous fluid. Also, when using a viscous fluid with a relatively low viscosity, the viscous fluid is discharged together with the gas extracted from the gas extraction port due to the high fluidity of the viscous fluid, hindering the downstream degassing pump. There was a risk of causing

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems of the conventional art. An object of the present invention is to provide a fluid transport system that can be discharged from a viscous fluid outlet.

a pair of pump screws that are screwed together and driven to rotate in a non-contact manner; a cylindrical pump casing that accommodates the pair of pump screws in a non-contact manner; A viscous fluid intake port, a viscous fluid discharge port provided on the tip end side of the pump casing, a gas discharge port provided on the upper surface of the pump casing more distal than the viscous fluid intake port, and the gas discharge port. and a degassing pump connected via a degassing pipe to pass gas between the side surfaces of the pair of pump screws and between the tip surface of each pump screw and the inner peripheral surface of the pump casing. A fluid conveying system having a twin-screw pump section formed with a gap impermeable to a viscous fluid, wherein the pump casing of the twin-screw pump section is inclined forward and downward to: An air collecting space is formed in the rear upper part of the pump casing on the distal side of the viscous fluid intake, and the gas outlet is formed at a position facing the air collecting space from above on the distal side of the pump casing. It has a configuration characterized by

In the above configuration, the tilt angle of the two-screw pump section with respect to the horizontal direction of the pump casing is set to 30 degrees or more and 75 degrees or less.

In each of the above configurations, a vent pipe connected to the pump casing for introducing outside air into the air collecting space, a space pressure detector for detecting the pressure in the air collecting space, and a degassing pipe. A degassing on-off valve that opens and closes, a vent on-off valve that opens and closes the conduit of the vent pipe, and a pressure in the gas collection space detected by the space pressure detector so as to approach the preset space pressure and a first controller for controlling the opening and closing of the degassing on-off valve and the venting on-off valve.

Furthermore, in each of the above configurations, a cushion tank interposed in the middle of the degassing pipe of the twin screw pump section, a regulator valve disposed in the degassing pipe between the cushion tank and the degassing pump, and a cushion tank a second controller that controls the opening and closing of the regulator valve so that the pressure in the cushion tank detected by the tank pressure detector approaches the preset set tank pressure; It is characterized by comprising

Further, in each of the above configurations, the circulatory system in which the discharge pipe connected to the viscous fluid discharge port of the pump casing in the twin-screw pump section and the supply pipe connected to the viscous fluid intake port of the pump casing are connected in an annular fashion. A pipe, a first detour pipe connecting the vent pipe and the middle of the circulation pipe, a second detour pipe connecting the degassing pipe and the middle of the circulation pipe, and a drain discharge pipe branched and connected to the middle of the carry-out pipe. is characterized by comprising:

According to the fluid conveying system of the present invention, since the pump casing of the twin-screw pump portion is inclined forward and downward, the gas separated from the viscous fluid in the pump casing is discharged from the viscous fluid intake at the end of the pump casing. It gathers at the rear upper position in the pump casing on the side to form a coherent collection space. A gas extraction port is opened on the upper surface of the pump casing at a position communicating with the air collecting space. As mentioned above, the gas gathers in the rear upper part of the casing to form a wide collection space, and the gas is reliably discharged out of the casing through the gas discharge port opened at that position. There is no possibility that the viscous fluid will be discharged together with the gas, and the viscous fluid with a low gas content can be discharged from the viscous fluid outlet of the pump casing.

In addition, in the case where the inclination angle of the pump casing of the twin-screw pump section with respect to the horizontal direction is set to 30 degrees or more and 75 degrees or less, the viscosity of the applied viscous fluid is relatively low (for example, 1000 cp (1 Pa s) or less), the viscous fluid can be transported by reliably degassing. It should be noted that there is a suitable inclination angle θ according to the viscosity of the applied viscous fluid (for example, about 0.2 to 1 Pa·s). Incidentally, if the inclination angle θ is less than 30 degrees, it may be difficult to collect the gas in the viscous fluid, and a wide gas collection space cannot be formed, resulting in a problem that a viscous fluid with an extremely low gas content cannot be obtained. If the inclination angle θ exceeds 75 degrees, there is a risk that the opening position of the gas extraction port or the like will be restricted.

Then, in the one equipped with a vent pipe, a space pressure detector, a degassing on-off valve, a vent on-off valve, and a first controller, the pressure in the gas collection space detected by the space pressure detector , the first controller controls the opening and closing of the degassing on-off valve and the venting on-off valve, and brings the detected pressure closer to the preset set space pressure. For example, when the detected pressure is lower than the set space pressure (when the degree of vacuum is high), the first controller slightly throttles the degassing on-off valve and slightly opens the venting on-off valve to collect outside air. Introduce a small amount into the space. As a result, the gas flows in the air collecting space, so that the degassing ability of the degassing pump can be well maintained. On the other hand, if the detected pressure exceeds the set space pressure (when the degree of vacuum is low), open the degassing on-off valve and slightly throttle the venting on-off valve to reduce the degassing capacity of the degassing pump. It is made to output at full. By adopting such a configuration, the pressure in the gas collection space can be precisely maintained at the set space pressure regardless of the degree of vacuum in the gas collection space.

Furthermore, in the case where the cushion tank interposed in the middle of the degassing pipe, the regulator valve, the tank pressure detector, and the second controller are provided, the pressure in the cushion tank detected by the tank pressure detector , the second controller controls the opening and closing of the regulator valve to bring the detected tank pressure closer to the preset set tank pressure. For example, if the detected tank pressure is below the set tank pressure, the second controller reduces the opening of the regulator valve to lighten the load on the degassing pump. On the other hand, if the detected tank pressure exceeds the set tank pressure, the second controller increases the degree of opening of the regulator valve to output the degassing capacity of the degassing pump. With such a configuration, even if the pressure in the cushion tank fluctuates due to external air introduced from the vent pipe on the upstream side of the degassing path, the degassing pump can be operated by performing precise opening/closing control of the regulator valve. Since the pressure on the suction side is kept constant, the degassing pump can be stably operated without being influenced by the pressure inside the pump casing.

In addition, in the case where the circulation pipe connecting the carry-out pipe and the supply pipe in a ring shape, the first bypass pipe, the second bypass pipe, and the drain discharge pipe are provided, the fluid transport system is individually disassembled for cleaning. A so-called CIP type cleaning can be performed in which the inside of the pipe is cleaned in an assembled state without cleaning. Therefore, it is possible to provide a fluid transport system that is easy to handle when applying viscous fluids such as foods, cosmetics, and pharmaceuticals.

1 is a schematic side view of a fluid transport system according to an embodiment of the present invention; FIG. FIG. 3 is a partial side view of the fluid delivery system; FIG. 3 is a partial plan view taken along the line DD in FIG. 2; FIG. 3 is a partial plan view taken along line CC in FIG. 2; FIG. 3 is a partial plan view taken along line EE in FIG. 2; 8 is an internal configuration diagram including a cross section taken along the line LL in FIG. 7 of the twin screw pump section of the fluid transfer system; FIG. It is an internal plane block diagram including the partial cross section of the said twin-screw pump part. Fig. 3(a) is a partially enlarged plan view showing the gap between the pair of pump screws, and (b) is the gap between the pump screw and the inner peripheral surface of the pump casing. is a partially enlarged plan view showing a gap between. FIG. 4 is a schematic side view showing a state in which a viscous fluid is normally transported using the fluid transport system; FIG. 4 is a schematic side view showing a state when PIG cleaning is performed using the fluid transport system; FIG. 4 is a schematic side view showing a state in which CIP cleaning in place is performed using the fluid transport system;

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. It should be noted that the embodiment described below is merely an example that embodies the present invention, and does not limit the technical scope of the present invention. Here, FIG. 1 is a schematic side view showing a fluid transport system according to one embodiment of the present invention, FIG. 2 is a partial side view of the fluid transport system, and FIG. 3 is a view taken along line DD in FIG. 4 is a partial plan view seen along line CC in FIG. 2, and FIG. 5 is a partial plan view seen along line EE in FIG.
In each figure, a fluid transfer system A according to this embodiment includes a twin screw pump section B as a main component. The detailed structure of the twin screw pump portion B will be described later with reference to FIGS.

In this fluid transport system A, the pump casing 2 of the twin-screw pump section B is arranged with an inclination angle θ (45 degrees in this example) in a downward forward direction. That is, in the pump casing 2, a base 82 (see FIGS. 2 and 3) attached to the bottom portion of the bearing portion 5 is fixed by bolts or the like to an inclined table 81 provided at an upper portion of the base frame 80. As a result, it is held in an arrangement inclined forward and downward. At this time, the inclination angle θ of the pump casing 2 with respect to the horizontal direction (the direction indicated by the dashed line H in FIG. 6) is set at, for example, 45 degrees. By slanting the pump casing 2 in this way, when the viscous fluid Q was conveyed, it was contained in the viscous fluid Q at the end side of the viscous fluid intake port 18 and in the rear upper part of the pump casing 2. The gas collects to form a gas collecting space 17 . A gas extraction port 20, an outside air introduction port 29, and a sensor mounting port 30 are formed through the upper surface of the pump casing 2 at a position communicating with the air collecting space 17 so as to pass through the casing.

The carry-out pipe 33 connected to the viscous fluid discharge port 19 of the discharge side casing 3 of the pump casing 2 includes, in order from the viscous fluid discharge port 19 side, a check valve 28, a sight glass 58, an electromagnetic on-off valve 60, a flow A path switching pipe 33A and a catcher 65b are interposed. The end of the discharge pipe 33 is connected to the filling tank 83 from the catcher 65b. A fluid detector 59 is provided on the side of the sight glass 58 to detect the presence or absence of the viscous fluid Q flowing through the sight glass 58 and the liquid level. A drain discharge pipe 34 having an electromagnetic opening/closing valve 61 is branched and connected to the carry-out pipe 33 between the sight glass 58 and the electromagnetic opening/closing valve 60 . Further, an air introduction pipe 64 having a launcher 62b is branched and connected to the carry-out pipe 33 between the electromagnetic on-off valve 60 and the channel switching pipe 33A. The launcher 62b is loaded with PIG balls 44 that are received in the catcher 65b after PIG cleaning of the inside of the tube, and is connected to a compressed air line for driving.

The channel switching pipe 33A is curved in a quadrant shape, and is made of a SUS pipe material with an inlet side and an outlet side forming an angle of 90 degrees. The channel switching pipe 33A has a flange 33C at one end and a flange 33B at the other end. The flange 33C of the channel switching pipe 33A is fixed by bolts or the like to a flange 84 provided at the end of the carry-out pipe 33, and the flange 33B is detachably fixed to the flange 81 of the carry-out pipe 33 by bolts or the like. In addition, the flange 33C is connected to the flange 84 so that the mounting angle can be changed so that the flow path switching pipe 33A can turn around the pipe center of the carry-out pipe 33. As shown in FIG. A flange 82 that is one end of the circulation pipe 40 of the CIP line 78 is arranged at a position where the flange 33B is turned 180 degrees from the flange 81 of the carry-out pipe 33 . The flange 33B of the channel switching pipe 33A is detachably fixed also to the flange 82 with bolts or the like. With such a switching connection structure, the flow of the viscous fluid Q from the electromagnetic on-off valve 60 is switched between the filling tank 83 side and the circulation pipe 40 side.

The supply pipe 32 connected to the viscous fluid inlet 18 of the pump casing 2 is provided with a sight glass 56, a manual on-off valve 55, a catcher 65a, and an electromagnetic on-off valve 54 in this order from the viscous fluid inlet 18 side. , the end of the supply pipe 32 is connected to the bottom of the fluid receiving tank 31 . A fluid inlet (not shown) is provided on the upper surface of the fluid receiving tank 31, and a water supply pipe 43 having a manual on-off valve is also connected. Washing water is supplied to the fluid receiving tank 31 from the water supply pipe 43 . An air introduction pipe 39 having a launcher 62a is branch-connected to the supply pipe 32 between the electromagnetic on-off valve 54 and the catcher 65a. The launcher 62a is loaded with a PIG ball 44 for cleaning the PIG inside the tube, and is connected to a compressed air line for driving. A fluid detector 57 is provided on the side of the sight glass 56 to detect the presence or absence of the viscous fluid Q flowing through the sight glass 56 and the liquid level. The catcher 65a described above receives the PIG balls 44 that have been cleaned by PIG.

The deaeration pipe 35 connected to the gas discharge port 20 of the pump casing 2 is provided with a manual on-off valve 75 and a deaeration on-off valve 69 for opening and closing the conduit of the deaeration pipe 35 in order from the gas discharge port 20 side. A gas-liquid separation tank 47 of a degassing unit 45 is connected to the end of the degassing pipe 35, and the gas-liquid separation tank 47 is configured so that the inside of the tank can be visually recognized from the outside. An upper portion of the gas-liquid separation tank 47 communicates with an upper portion of the cushion tank 46 via a degassing pipe 48 . The cushion tank 46 is connected to the suction side of the degassing pump VP via a degassing pipe 50 having a regulator valve 53 of, for example, an electrostatic conversion type. A tank pressure detector 49 for detecting tank internal pressure is arranged on the upper portion of the cushion tank 46, and a vent pipe 51 having an electromagnetic on-off valve 52 is also arranged. The regulator valve 53 is precisely controlled to open and close by the second controller 77 so that the tank internal pressure detected by the tank pressure detector 49 approaches the preset tank pressure. .

A vent pipe 36 connected to the outside air introduction port 29 of the pump casing 2 is for introducing outside air into the air collection space 17 of the pump casing 2 . A manual on-off valve 73 and a vent on-off valve 72 for opening and closing the conduit of the vent pipe 36 are interposed in this vent pipe 36 in this order from the outside air introduction port 29 side. A space pressure detector 74 for detecting the pressure in the gas collecting space 17 is connected to the sensor mounting port 30 of the pump casing 2 . A first bypass pipe 37 having an electromagnetic on-off valve 71 connects the vent pipe 36 between the manual on-off valve 73 and the vent on-off valve 72 to an intermediate position of the circulation pipe 40 . The degassing pipe 35 between the manual on-off valve 75 and the deaeration on-off valve 69 to the middle of the circulation pipe 40 is connected by a second bypass pipe 38 having an electromagnetic on-off valve 70 . A circulation pipe 41 having an electromagnetic opening/closing valve 66 and a manual opening/closing valve 67 is connected from the tip of the circulation pipe 40 to the fluid receiving tank 31 . A circulation pipe 42 having an electromagnetic on-off valve 68 is also connected between the connecting portion of the circulation pipe 40 and the circulation pipe 41 and the fluid receiving tank 31 . That is, circulation pipes 40, 41, and 42 annularly connected by connecting the discharge pipe 33 from the pump casing 2, the channel switching pipe 33A, the fluid receiving tank 31, and the supply pipe 32, a first bypass pipe 37, and a second A CIP line 78 is configured from the bypass pipe 38 and the drain discharge pipe 34 .

It should be noted that a component attached to each pipe and denoted by "SG" represents a sight glass made of a glass tube through which the inside of the pipe can be visually recognized. Since this fluid transport system A also serves as a testing machine, many sight glasses SG are used in the system, but the number of sight glasses SG used is not particularly limited in the present invention. Also, the symbol of a right triangle attached to the side of each pipe indicates that the inclination of the pipe is downward with respect to the horizontal direction in the direction in which the oblique side is downward. In other words, the fluid transfer system A having the CIP line 78 is adapted to wash and sterilize the SIP (sterilization in place) type, which is configured so that the fluid in the pipe flows down and collects at a predetermined location after system operation is stopped. .

Next, as shown in FIGS. 6, 7 and 8, the twin-screw pump section B comprises a cylindrical pump casing 2 penetrating in the front-rear direction and a bearing 5 connected to the rear end of the pump casing 2. , is equipped with A discharge-side casing 3 is connected to the front end portion of the pump casing 2 , and a pipe portion 4 is connected to the front end portion of the discharge-side casing 3 . A pair of pump screws 7a and 7b are accommodated in the pump casing 2. As shown in FIG. The front ends of the pump screws 7a, 7b fixed to the shafts 8a, 8b by setscrews or the like form free ends 26, 26 which are not supported by bearings or the like. The free ends 26, 26 of these pump screws 7a, 7b are applied with fixing plates 14, 14 and fixed to the shafts 8a, 8b by bolts 15, 15, for example. The spiral direction of the pump screw 7a and the spiral direction of the pump screw 7b are opposite.

The bearing portion 5 is formed in a box shape by a housing 9 and a cover plate 10 , and the front end face of the cover plate 10 is connected to the cylindrical end face of the pump casing 2 . Conical roller bearings 11 and 11 and roller bearings 12 and 12 are arranged in the housing 9 . These roller bearings 11 and 12 rotatably support the rear end portion of the shaft portion 8a of the pump screw 7a in a cantilever manner. The rear end portion of the shaft portion 8b of the pump screw 7b is also rotatably supported in a cantilever manner by separate conical roller bearings 11 and 12. As shown in FIG. That is, the rear portions of the pump screws 7a and 7b are supported at two points within the housing 9 so as to be freely rotatable. Sealing mechanisms 16, 16 are mounted on the pump screws 7a, 7b in the vicinity of the cover plate 10 within the housing 9. As shown in FIG. A synchronous gear 13a is fixed to the shaft portion 8a of the pump screw 7a, and a synchronous gear 13b that meshes with the synchronous gear 13a is fixed to the shaft portion 8b of the pump screw 7b. Due to the synchronous meshing of the synchronous gears 13a and 13b, the pair of pump screws 7a and 7b mesh without coming into contact with each other at any rotation angle. That is, the pump screws 7a and 7b rotate while being screwed together without contact. In this case, for example, the shaft portion 8a of the pump screw 7a serves as a drive shaft and is connected to the motor M via a connection mechanism 27 such as a reduction mechanism.

The pump casing 2 is formed with a cocoon-shaped pump chamber 6 penetrating therethrough in the front-rear direction. A cylindrical discharge-side casing 3 is connected to the front end of the pump casing 2 . A tubular pipe portion 4 having a viscous fluid discharge port 19 is connected to the front end portion of the discharge side casing 3 . One end of a carry-out pipe 33 is connected to the tip of the pipe portion 4 , and a check valve 28 is arranged in the middle of the carry-out pipe 33 . The check valve 28 allows the viscous fluid Q to flow only in the viscous fluid transfer direction, and is normally closed by the spring elastic force of the spring member. The pump chamber 6 accommodates a pump screw 7a that rotates about the axis Xa and a pump screw 7b that rotates about the axis Xb while constantly screwing the pump screw 7a in a non-contact manner. The outer peripheral surfaces of the pair of pump screws 7a and 7b are always kept out of contact with the inner peripheral surface 2A of the pump chamber 6 as will be described in detail later. On the other hand, a viscous fluid intake port 18 that communicates between the pump chamber 6 and the supply pipe 32 is formed on the lower surface of the pump casing 2 at a position slightly behind the front-rear central portion.

A pipe portion 21 having a ferrule joint portion at the bottom opening edge is fixed by bolts or the like to the lower surface of the pump casing 2 surrounding the viscous fluid inlet 18 , and a supply pipe 32 is connected to the lower surface opening of the pipe portion 21 . be. On the other hand, in the ceiling surface of the rear end portion of the pump chamber 6, a laterally extending ventilation groove 23 is formed by recessing upward. The pump casing 2 above the ventilation groove 23 is provided with a gas extraction port 20, an outside air introduction port 29, and a sensor mounting port 30 for communicating the ventilation groove 23 with the upper outside of the casing. That is, the gas extraction port 20, the outside air introduction port 29, and the sensor mounting port 30 are formed in the pump casing 2 upstream of the viscous fluid intake port 18 in the viscous fluid transfer direction. The gas extraction port 20 is connected to the above-described degassing pump VP for extracting gas from the pump chamber 6 through a degassing pipe 35 such as a pipe material. As the degassing pump VP, for example, a piston-cylinder type decompression pump is used here, but a centrifugal fan type decompression pump or an air ejector type may also be used.

The pair of pump screws 7a, 7b has spiral screw teeth formed on the outer peripheral surfaces of cylindrical bases 7A, 7A through which the shafts 8a, 8b are inserted. Then, as shown in FIG. 8(a), a gap G is provided between the side surface 7Sa of the screw teeth of the pump screw 7a and the side surface 7Sb of the screw teeth of the pump screw 7b so that they are always out of contact. . A gap H is provided between the outer peripheral surface 7B of the screw teeth of the pump screws 7a and 7b and the inner peripheral surface 2A of the pump chamber 6 of the pump screw 2, as shown in FIG. 8(b). Always contactless. In other words, these gaps G and H always exist regardless of the rotational angle of the pair of pump screws 7a and 7b. Both of the gaps G and H are set to a gap width that allows the gas K such as air to pass through but does not allow the high-viscosity liquid of the viscous fluid Q and hard/soft solids to pass through. In this case, the gap width of the gap G is, for example, 0.03 to 0.09 mm, and the gap width of the gap H is, for example, 0.12 to 0.18 mm. It is within the region P shown in FIGS. Within the range of this region P, the range of region pa shown in FIGS. In addition, when food, medicine, cosmetic materials, etc. are applied to the fluid transport system A, it is desirable to use stainless steel as the parts that come into direct contact with the viscous fluid Q from the viewpoint of hygiene and quality maintenance. . The rated pump capacity of the twin-screw pump section B is, for example, 10 to 120 L/min.

Next, the operation of the fluid transport system A configured as described above will be described. Examples of the viscous fluid Q that can be used for transportation include foods such as grated tororoimo, whole eggs, egg yolks, dumpling materials and noodle materials, liquid cosmetics such as creams and lotions, industrial materials such as molten synthetic resins, or Examples include liquid materials for medical use. Here, as the viscous fluid Q having a relatively low viscosity, one having a relative viscosity of, for example, 0.3 to 1 Pa·s can be used. The handling temperature of the viscous fluid Q varies depending on the type of fluid, but is, for example, normal temperature to about 200.degree. Here, an example using a "lotion" having a relative viscosity of 0.7 Pa·s is shown.

Next, the manner in which the fluid transport system A normally transports the viscous fluid Q will be described. The piping line-up for this normal transportation is as shown in FIG. In FIGS. 9, 10, and 11, the ○ mark in parentheses on the side of the on-off valve indicates that the valve is open, and the X mark in parentheses indicates that the valve is closed. ing. Further, the thick solid line arrow indicates the flow direction of the viscous fluid Q in the tube, the thick dashed line arrow indicates the flow direction of the fluid containing gas in the tube, and the thick wavy line arrow indicates the flow direction of the compressed air in the tube. .

During normal transportation, the manual on-off valves 55, 67, 73, 75 of the fluid transportation system A are all opened, and the manual on-off valve of the water supply pipe 43 to the fluid receiving tank 31 is closed. On the other hand, the electromagnetic on-off valves 54, 60, the degassing on-off valve 69, the venting on-off valve 72, and the regulator valve 53 are in an open state or a state that can be opened. 52 is fully closed. All the electromagnetic on-off valves are driven to open and close according to the operating mode by sequence control means (not shown) that controls the entire system.
In the fluid receiving tank 31, a viscous fluid Q to be used for fluid transportation is introduced from a fluid inlet (not shown) and stored therein. Therefore, while the motor M of the twin-screw pump section B is stopped, the spatial pressure detector 74, the vent opening/closing valve 72, the degassing opening/closing valve 69, the first controller 76, the tank pressure detector 49, the first controller 76, and the tank pressure detector 49, The regulator valve 53 and the second controller 77 are placed in an operation standby state, and the degassing pump VP is driven. As a result, the priming mode for removing gas, water, etc. from the system of the fluid transport system A is executed. At this time, the set space pressure in the pump casing 2 is preset to 0.05 Mp (absolute pressure: absolute vacuum is 0 Mp), and the set pressure on the suction side of the degassing pump VP is preset to 0.03 Mp (absolute pressure). is set.

Subsequently, when the pump screw 7a is rotated in one direction by the rotational drive of the motor M, the pump screw 7b to which power is transmitted via the synchronous gears 13a and 13b is synchronously rotated in the opposite direction. The rotational speed of the pump screws 7a, 7b at this time is, for example, 100 to 600 rpm. The viscous fluid Q from the fluid receiving tank 31 is sucked into the pump chamber 6 of the pump casing 2 from the viscous fluid inlet 18 through the supply pipe 32 . At this time, the passing state of the viscous fluid Q passing through the sight glass 56 is detected by the fluid detector 57 . The viscous fluid Q is conveyed through the pump chamber 6 toward the discharge side casing 3 by the pump action of the pump screws 7a and 7b.

In this case, since the inside of the pump chamber 6 is evacuated by the degassing pump VP, bubbles are separated from the viscous fluid Q, and the viscous fluid Q moves in the direction of viscous fluid transfer (direction of arrow F) in the pump chamber 6. easily move in the opposite direction (ie towards the upstream side in the direction of transport). At this time, air bubbles are generated in the gap H between the inner peripheral surface 2A of the pump casing 2 and the outer peripheral surface 7B of the pump screws 7a and 7b (see FIG. 8B), the side surface 7Sa of the pump screw 7a and the side surface of the pump screw 7b. It passes through the gap G (see FIG. 8A) with 7Sb and moves backward in the area pa. After that, the moved air bubbles gather at the rear upper portion of the pump casing 2 to form an air collecting space 17 . The gas in the air collecting space 17 is sucked out of the machine from the gas extraction port 20 through the degassing pipe 35 by the action of the degassing pump VP. As a result, the viscous fluid Q from which bubbles have been largely removed is delivered from the viscous fluid discharge port 19 to the check valve 28 . The check valve 28 closed by the spring member opens against the spring elastic force of the spring member when the inlet pressure reaches a positive pressure of 0.05 MPa, for example, and allows the viscous fluid Q to pass through. Let Then, the viscous fluid Q from the electromagnetic on-off valve 60 passes through the channel switching pipe 33A and the catcher 65b in the middle of the discharge pipe 33 and is conveyed to the tank 83 for filling.

The viscous fluid Q sent out from the check valve 28 contained almost no gas, and the presence of air bubbles could not be confirmed with the naked eye. Further, by removing the gas, the moisture originally contained in the viscous fluid Q is also removed from the system together with the gas. As described above, the viscous fluid Q in which almost no air bubbles can be seen in the carry-out pipe 33 has a higher apparent specific gravity than the conventional fluid containing many air bubbles and moisture, and the variation in the detected specific gravity value is extremely small. The oxidative deterioration of the film can also be prevented. Therefore, we were able to greatly contribute to the improvement and stabilization of product quality.

As described above, according to the fluid transfer system A of this embodiment, since the pump casing 2 of the twin screw pump section B is arranged at an angle of 45 degrees downward forward, the viscous fluid intake 18 is Air bubbles can be collected to form a relatively wide air collecting space 17 at the rear upper position in the pump casing 2 on the distal end side (rear side). A gas extraction port 20 , an outside air introduction port 29 , and a sensor mounting port 30 are opened on the upper surface of the pump casing 2 at a position communicating with the air collecting space 17 . Therefore, only the gas can be reliably extracted to the outside of the casing from the gas extraction port 20 opened at that position, and the viscous fluid Q with extremely low gas content and moisture content is discharged from the viscous fluid discharge port 19. be able to.

The first controller 76 controls the opening and closing of the degassing on-off valve 69 and the venting on-off valve 72 in accordance with the pressure in the gas collection space 17 detected by the space pressure detector 74, and is set in advance. The detected pressure in the gas collection space 17 is brought close to the set space pressure. For example, when the detected pressure is lower than the set space pressure (when the degree of vacuum is high), the first controller 76 throttles the degassing on-off valve 69 and opens the venting on-off valve 72 to allow outside air to flow into the air collecting space 17 . be introduced inside. As a result, the absolute pressure in the air collecting space 17 is slightly increased and the gas flows in the space, so that the degassing capability of the degassing pump VP can be easily drawn out. On the other hand, when the detected pressure exceeds the set space pressure (when the degree of vacuum is low), the degassing on-off valve 69 is opened and the venting on-off valve 72 is throttled to tighten the degree of vacuum by the degassing pump VP. be. Thereby, the pressure in the gas collection space 17 can be accurately maintained at the set space pressure.

In addition, the second controller 77 opens and closes the regulator valve 53 according to the pressure in the cushion tank detected by the tank pressure detector 49, and brings the detected tank pressure close to the preset set tank pressure. For example, when the detected tank pressure is lower than the set tank pressure (when the degree of vacuum is high), the second controller 77 reduces the degree of opening of the regulator valve 53 to lighten the load on the degassing pump VP. On the other hand, when the detected tank pressure exceeds the set tank pressure (when the degree of vacuum is low), the second controller 77 increases the degree of opening of the regulator valve 53 to output the degassing capacity of the degassing pump VP. As a result, even if the pressure in the cushion tank 46 fluctuates due to the outside air introduced from the vent pipe 36, the regulator valve 53 is precisely opened and closed, so the pressure on the suction side of the degassing pump VP can be kept constant. can. Therefore, the degassing pump VP can be stably operated without being influenced by the pressure inside the pump casing 2 .

Further, the twin-screw pump portion B of the fluid transfer system A can transfer the viscous fluid Q while removing gas and water, and the pump screws 7a and 7b and the inner peripheral surface 2A of the pump casing 2 are not in contact with each other. This pump device is suitable for transporting foodstuffs, medical products, etc., without generating metal abrasion powder, and without imparting a shear force to the viscous fluid Q and deteriorating it, unlike when it receives the centrifugal force of a centrifugal pump. obtain. Further, since the check valve 28 is provided on the output side of the viscous fluid discharge port 19 of the pump casing 2, even if the viscous fluid Q from a position below the viscous fluid intake port 18 of the pump casing 2, By the action of the stop valve 28, the pump chamber 6 can be sucked up.

Next, the cleaning mode of this fluid transport system A by the CIP method will be described. The piping line-up for this CIP type cleaning is as shown in FIG. 10, but the structure of the fluid transfer system A is assembled as it is during normal operation, and none of it has been disassembled. During this cleaning mode, the open electromagnetic on-off valve 60 and venting on-off valve 72 are closed, and the closed electromagnetic on-off valve 61 is opened for the piping line-up for normal transportation shown in FIG. Also, the control using the first controller 76 is stopped. The motor M of the twin-screw pump section B is stopped, but the degassing pump VP is driven to rotate.

First, PIG cleaning for the supply pipe 32 will be described. A rubber PIG ball 44 is loaded into the launcher 62a, and a manual on-off valve for compressed air is opened to inject high-pressure compressed air into the launcher 62a. As a result, the PIG ball 44 fired from the launcher 62a enters the supply pipe 32 from the air introduction pipe 39, and rubs and cleans the inner wall of the pipe while passing through the supply pipe 32 as indicated by the arrow indicated by the thick dashed line. It is later received by the catcher 65a together with the viscous fluid Q and compressed air. After that, the viscous fluid Q and compressed air pass through the catcher 65a and enter the pump casing 2 of the twin-screw pump section B through the sight glass 56. As shown in FIG. Among them, the viscous fluid Q is discharged from the viscous fluid discharge port 19 of the pump casing 2 to the outside of the system as a drain through the discharge pipe 33, the check valve 28, the sight glass 58, the drain discharge pipe 34 and the electromagnetic on-off valve 61.

Next, PIG cleaning for the carry-out pipe 33 will be described. A PIG ball 44 is loaded in the launcher 62b, and the compressed air manual opening/closing valve is opened to inject compressed air into the launcher 62b. As a result, the PIG ball 44 fired from the launcher 62b enters the carry-out pipe 33 from the air introduction pipe 64, passes through the flow path switching pipe 33A, and PIG cleans the inner wall of the pipe, as indicated by the thick dashed-dotted arrow. do. The PIG ball 44 is then received by the catcher 65b together with the viscous fluid Q and compressed air. Furthermore, the compressed air and the viscous fluid Q in the catcher 65b are discharged to the tank 83 for filling. In this manner, the PIG cleaning and air purging operations inside the supply pipe 32 and the carry-out pipe 33 are performed.

Next, a CIP cleaning mode using cleaning water in this fluid transport system A will be described. The piping line-up for this water washing is as shown in FIG. 11, but the structure of the fluid transport system A is assembled as it is during normal operation, and none of it has been disassembled. In this water cleaning mode, the open electromagnetic on-off valve 61 and the manual on-off valves for compressed air of the launchers 62a and 62b are closed, and the closed electromagnetic on-off valves are closed for the piping line-up for PIG cleaning shown in FIG. Valves 68, 60 and vent on-off valve 72 are opened. Further, control using the first controller 76 is performed, and the degassing pump VP is also rotationally driven. Further, the channel switching pipe 33A is switched from the catcher 65b side to the circulation pipe 40 side as indicated by the solid line.
Then, the manual opening/closing valve of the water supply pipe 43 is opened to inject the cleaning water into the fluid receiving tank 31 . Then, the motor M of the twin-screw pump section B rotates at a high speed of 3600 rpm, and the pump casing 2, the discharge pipe 33, the flow path switching pipe 33A, the circulation pipe 40, the circulation pipe 42, the fluid receiving tank 31, the supply pipe 32, and the catcher. In 65a, washing water is circulated at high speed to wash the inside of the system.

Next, CIP circulation cleaning is performed on the air collection space 17 in the pump casing 2 near the cover plate 10 . First, in the state of the piping line-up during water cleaning, the control using the first controller 76 is stopped and the opening/closing valve 72 for venting is closed, and the motor M of the twin-screw pump section B is rotated from 100 to 600 rpm. It is made to rotate at a low speed. This prepares for CIP circulation cleaning.
That is, by opening the electromagnetic on-off valves 70 and 71 and rotating the motor M of the twin screw pump section B at a high speed of about 3600 rpm, the wash water discharged from the viscous fluid discharge port 19 of the pump casing 2 is In addition to performing general circulation around the carry-out pipe 33, the flow channel switching pipe 33A, the circulation pipe 40, the circulation pipe 42, the liquid receiving tank 31, the supply pipe 32 and the catcher 65a, the flow from the circulation pipe 40 to the first bypass pipe 37 and the second Since the washing water is also passed through the bypass pipe 38 and injected at high speed into the air collection space 17 near the cover plate 10 in the pump casing 2, it is possible to reliably wash the relevant portion.

As described above, this fluid transport system A can perform so-called CIP cleaning and SIP (sterilization in place), in which the inside of the system is cleaned in an assembled state without disassembling the fluid transport system A individually. . Therefore, it is possible to provide a system that is easy to handle when applying viscous fluids such as food, cosmetics, and pharmaceuticals.

In addition, in the above-described embodiment, an example of using the check valve 28 on the discharge side of the twin screw pump section B is shown, but the present invention is not limited thereto. For example, the present invention includes a fluid transfer system that does not have a check valve on the pump discharge side. Although such a fluid transfer system cannot suck in viscous fluid located at a position lower than the viscous fluid intake, on the other hand, CIP cleaning and SIP (sterilization in place) can be easily performed since a complicated structure is eliminated.

Further, the present invention is not limited to the above-described embodiments, and includes various modifications and modifications that can be conceived by those who have ordinary knowledge in the field of the present invention. It goes without saying that even if there is a design change that does not occur, it is included in the present invention.

A fluid transfer system B twin screw pump section 2 pump casing 2A inner peripheral surface 6 pump chambers 7a, 7b pump screws 7Sa, 7Sb side surface 7B tip end surface 17 air collection space 18 viscous fluid intake port 19 viscous fluid discharge port 20 gas extraction port 28 Check valve 29 Outside air inlet 30 Sensor mounting port 31 Fluid receiving tank 32 Supply pipe 33 Carry-out pipe 33A Flow path switching pipe 34 Drain discharge pipe 35 Degassing pipe 36 Vent pipe 37 First bypass pipe 38 Second bypass pipes 40, 41, 42 Circulation pipe 46 Cushion tank 49 Tank pressure detector 53 Regulator valve 69 Deaeration on-off valve 72 Vent on-off valve 74 Spatial pressure detector 76 First controller 77 Second controller 78 CIP line F Arrows G, H Gap Q Viscous fluid VP Degassing pumps Xa, Xb Shaft center θ Tilt angle

Claims (5)

a pair of pump screws that are screwed together and driven to rotate in a non-contact manner; a cylindrical pump casing that accommodates the pair of pump screws in a non-contact manner; A viscous fluid intake port, a viscous fluid discharge port provided on the tip end side of the pump casing, a gas discharge port provided on the upper surface of the pump casing more distal than the viscous fluid intake port, and the gas discharge port. and a degassing pump connected via a degassing pipe to pass gas between the side surfaces of the pair of pump screws and between the tip surface of each pump screw and the inner peripheral surface of the pump casing. A fluid delivery system having a twin screw pump section with a clearance that allows and is impervious to viscous fluid,
By arranging the pump casing of the twin-screw pump portion so as to tilt forward and downward, an air collection space is formed in the rear upper portion of the pump casing on the distal side of the viscous fluid intake , wherein the gas extraction port is formed at a position facing the air collection space from above on the terminal side of the fluid transfer system. 2. The fluid transfer system according to claim 1, wherein an inclination angle of the pump casing of the twin-screw pump section with respect to the horizontal direction is set to 30 degrees or more and 75 degrees or less. a vent pipe connected to the pump casing for introducing outside air into the air collecting space;
a spatial pressure detector that detects pressure in the collection space;
a degassing on-off valve that opens and closes the channel of the degassing pipe;
a vent on-off valve that opens and closes the conduit of the vent pipe;
A first controller that controls opening and closing of the degassing on-off valve and the venting on-off valve so that the pressure in the gas collection space detected by the space pressure detector approaches a preset space pressure. and,
3. The fluid delivery system of claim 1 or claim 2, comprising: a cushion tank interposed in the middle of the degassing pipe of the twin-screw pump;
a regulator valve disposed in a degassing pipe between the cushion tank and the degassing pump;
a tank pressure detector that detects the pressure in the cushion tank;
a second controller that controls opening and closing of the regulator valve so that the pressure in the cushion tank detected by the tank pressure detector approaches a preset set tank pressure;
4. A fluid delivery system according to any one of claims 1 to 3, comprising: a circulation pipe annularly connecting a discharge pipe connected to the viscous fluid discharge port of the pump casing of the twin-screw pump section and a supply pipe connected to the viscous fluid intake port of the pump casing;
a first detour pipe connecting the vent pipe and the middle of the circulation pipe;
a second detour pipe connecting the degassing pipe and the middle of the circulation pipe;
a drain discharge pipe branched and connected in the middle of the carry-out pipe;
4. The fluid delivery system of claim 3, comprising:

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