JP2017223178A - Pipe device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To minimize an aperture of pipe without making a gas-phase space on an upstream side of a base pipe and a gas-phase space on a downstream side into a closed state, at a confluent part of liquid flowing in the base pipe arranged obliquely and liquid flowing in a branch pipe connected to the base pipe from above.SOLUTION: A pipe system includes a base pipe 11 arranged obliquely and configured to flow liquid Lha in a state of having a gas-phase space, and a branch pipe 12 connected to the base pipe 11 from above and configured to flow liquid Lhb in a state of having a gas-phase space and make the liquid Lhb confluent with the liquid Lha flowing in the base pipe 11. Gas-phase spaces on an upstream side and a downstream side with respect to a confluent part of the liquid Lha, Lhb from the base pipe 11 and branch pipe 12 always communicate with each other through an internal bypass pipe 13.SELECTED DRAWING: Figure 1

Description

  Embodiments of the present invention relate to a piping device for transporting a liquid while maintaining a gas phase space.

  For example, bearings for rotating bodies of turbines and generators in power plants such as thermal power and nuclear power are used to reduce energy loss and heat generation due to friction and prevent seizure of parts. The sliding bearing method is adopted.

  The oil supplied to the bearing is conveyed by arranging an oil pipe called a “bearing lubricating oil system”.

  FIG. 11 is a schematic view showing a general bearing lubricating oil system of a conventional power plant. FIG. 11A is an overall view thereof, and FIG.

With reference to FIG. 11, the flow of oil in the system will be sequentially described as (1) to (5) below.
(1) Starting from the main oil tank 31 for storing oil, the oil (low temperature) Lc in the main oil tank 31 is sucked up by the circulation pump 32 and pressurized, and the ascending supply pipe 33 and branch pipes 33a and 33b Then, the bearings 36a and 36b that support the turbine rotor 34 or the rotating shaft (shaft) 35 of the generator are supplied.
(2) In the bearings 36a and 36b, oil Lc is injected between the rotary shaft 35 and the bearings 36a and 36b, thereby facilitating the lubrication of the bearings 36a and 36b and at the same time being generated by friction with the rotary shaft 35. Remove heat.
(3) The oil (high temperature) Lh that has finished the roles of lubrication and heat removal in the bearings 36a and 36b is returned to the return branch pipes 12a and 12b and the descending return oil pipe 37 (return oil) from the bearings 36a and 36b. It returns to the main oil tank 31 again through the mother pipe 11). The supply pipe 33 and the return oil pipe 37 are conventionally designed as a double-structured pipe, often a supply pipe on the inside and a return pipe on the outside, for safety measures to ensure that the oil Lc (Lh) is a flammable fluid In recent years, it has become common to design with separate single tubes.
(4) The main oil tank 31 is generally provided with an oil cooler (oil cooler) 39, which is a heat exchanger, along with or built in the main oil tank 31, and returns to the main oil tank 31. After the temperature rise, the oil (high temperature) Lh is circulated to the oil cooler (oil cooler) 39 by the circulation pump 38 and the temperature is lowered to control the oil (low temperature) Lc at a constant temperature.
(5) The main oil tank 31 is provided with a blower (vacuum pump) 40. By discharging the air in the main oil tank 31 to the atmosphere, the pressure in the main oil tank 31 is made negative. The bearing portions 36a, 36b are made negative pressure from the return oil pipe 37 (return oil mother pipe 11) through the return branch pipes 12a, 12b. As a result, oil mist from the seal portions of the bearing portions 36a and 36b is prevented from being scattered to the outside, and at the same time, the steam leaked from the turbine 34 and the generator around the bearing portions 36a and 36b. Cooling gas is sucked and discharged.

  In addition, since a plurality of generators in an actual power plant are provided side by side, a bearing lubricating oil system starting from the main oil tank 31 is generally shared, so the bearing portion shown in FIG. 36a and 36b are also more present depending on the number of generators, whereby a large number of return branch pipes 12a, 12b,... Are connected to the return oil pipe 37 (return oil mother pipe 11).

Next, the arrangement and design concept of the bearing lubricant system in an actual power plant will be described below in (1) to (5).
(1) Generally, the position of the main oil tank 31 is arranged to be lower than the positions of the bearing portions 36a, 36b,. The “supply pipe 33” of the oil Lc from the main oil tank 31 to the bearing portions 36 a, 36 b,... Is configured by an upwardly inclined pipe, and the oil Lc is supplied by the circulation pump 32. On the other hand, the “return oil pipe 37” of the oil Lh from the bearing portions 36a, 36b,... Is constituted by a downwardly inclined pipe, and has a design concept of returning the oil Lh to the main oil tank 31 again by gravity.
(2) Therefore, when the circulation pump 32 stops due to a plant stop or the like, the oil Lc (Lh) circulating in the system returns to the main oil tank 31 by gravity.
(3) For the supply pipe 33, a check valve is installed at the outlet of the circulation pump 32, and the oil Lc in the supply pipe 33 does not flow back to the main oil tank 31 immediately after the pump is stopped. However, as time passes, it returns to the main oil tank 31 while leaking from the check valve and the thermometer orifice.
(4) As described above, in the bearing portions 36a, 36b,..., It is necessary to prevent oil (mist) leakage to the outside and suck and discharge unnecessary gas or gas. 36b, ... must be kept at a negative pressure. As one of means for making the bearings 36a, 36b,... Negative pressure, as described above, the internal pressure of the main oil tank 31 that is the starting point and the most downstream of the bearing lubricating oil system is used as a vacuum pump (blower) 40. A method of keeping the negative pressure at once is adopted. Therefore, the gas phase space is always maintained in the pipe composed of the return oil pipe 37 (return oil mother pipe 11) and the return branch pipes 12a, 12b, ... between the bearing portions 36a, 36b, ... and the main oil tank 31. It is essential that the liquid flow.
(5) That is, the design of the oil pipe of the bearing lubricating oil system differs between the supply pipe (33, 33a, 33b,...) And the return pipe (37, 11, 12a, 12b,...). 33, 33a, 33b,... Are designed to be a full oil flow, and the return oil pipes 37, 11, 12a, 12b,... Are designed to have a liquid surface (free surface). The inside of the supply pipes 33, 33a, 33b,... Is filled with pressure by the circulation pump 32, but the inside of the return oil pipes 37, 11, 12a, 12b,... Needs to keep the bearing portions 36a, 36b,. Therefore, it is necessary to maintain a space with a free liquid level over the entire pipe, and to design the gas phase space from the main oil tank 31 to the bearings 36a, 36b,.

  For this reason, the diameter of the conventional return oil pipe 37 (return oil mother pipe 11) is such that, for example, even if the oil Lh from the return branch pipes 12a, 12b,. Based on fluid formulas such as the Chezi formula, the design standard is to have a sufficiently large diameter.

Japanese Patent No. 4970228 JP 2003-222294 A

  The diameter of the conventional return oil pipe 37 (return oil mother pipe 11) of the bearing lubricating oil system is a large diameter of 1000 mm at the maximum from the design standard, which makes the power plant more compact, easier to construct, and lower in cost. This is a hindrance.

  Therefore, it is conceivable to reduce the diameter of the return oil pipe 37 (return oil mother pipe 11) as much as possible, but naturally, the smaller the diameter is, the more the entire return oil pipe 37 (return oil mother pipe 11) is. It becomes difficult to maintain the space where there is always a free liquid level across the tube.

  FIG. 12 is a diagram showing a state of blockage in the pipe that may occur when return oil (branch) Lhb from each bearing unit joins the mother pipe 11 during plant operation in the bearing lubricant system. .

  As shown in FIG. 12, as indicated by an arrow b from a return branch pipe 12 connected from above with respect to the return oil Lha flowing through the return oil mother pipe 11 having a downward slope θ as indicated by an arrow a. When the return oil Lhb drops and merges, in the merged portion of the return oils Lha and Lhb, stagnation is particularly likely to occur at the upstream side, and if the diameter of the mother pipe 11 is not sufficient, blockage in the pipe occurs. In this case, the gas phase space on the upstream side and the gas phase space on the downstream side of the junction in the mother pipe 11 are blocked, and the space pressures P1 and P2 cannot be kept the same.

  Therefore, in the case of the bearing lubricating oil system of the power plant, the bearing portions 36a, 36b,... Cannot be maintained at a negative pressure, and oil mist is prevented from scattering and unnecessary gas (hydrogen, etc.) is sucked and discharged. May not be possible.

  The problem to be solved by the present invention is that a gas phase space on the upstream side of the mother pipe at the junction of the liquid flowing in the inclined mother pipe and the liquid flowing in the branch pipe connected to the mother pipe from above. It is to provide a piping device capable of minimizing the diameter of the piping without closing the gas phase space on the downstream side.

  The piping device according to the embodiment includes a mother pipe that is arranged in an inclined manner and allows a liquid to flow in a state having a gas phase space, and is connected to the mother pipe from above and flows a liquid in a state that has a gas phase space. A branch pipe that joins the liquid flowing in the mother pipe, and a piping means that always connects the gas phase space upstream and the gas phase space downstream from the liquid junction of the mother pipe and the branch pipe. It is a feature.

  According to the piping apparatus according to the embodiment, the gas phase space on the upstream side of the mother pipe at the junction of the liquid flowing in the mother pipe arranged at an inclination and the liquid flowing in the branch pipe connected to the mother pipe from above. It is possible to minimize the diameter of the pipe without closing the downstream gas phase space.

It is sectional drawing which shows the piping apparatus of 1st Embodiment, The figure (A) is a structure explanatory drawing, The figure (B) is an effect explanatory drawing. It is sectional drawing which shows the piping apparatus of 2nd Embodiment, The figure (A) is a structure explanatory drawing, The figure (B) is an effect explanatory drawing. Sectional drawing which shows the other Example in the piping apparatus of the said 2nd Embodiment. It is sectional drawing which shows the piping apparatus of 3rd Embodiment, The figure (A) is a structure explanatory drawing, The figure (B) is an effect explanatory drawing. It is sectional drawing which shows the piping apparatus of 4th Embodiment, The figure (A) is a structure explanatory drawing, The figure (B) is an effect explanatory drawing. It is sectional drawing which shows the piping apparatus of 5th Embodiment, The figure (A) is a structure explanatory drawing, The figure (B) is an effect explanatory drawing. It is sectional drawing which shows the piping apparatus (Example 1) of 6th Embodiment, The figure (A) is a structure explanatory drawing, The figure (B) is an effect | action explanatory drawing. It is sectional drawing which shows the piping apparatus (Example 2) of 6th Embodiment, The figure (A) is a structure explanatory drawing, The same figure (B) is an effect | action explanatory drawing. It is sectional drawing which shows the piping apparatus (Example 1) of 7th Embodiment, The figure (A) is a structure explanatory drawing, The figure (B) is an effect | action explanatory drawing. It is sectional drawing which shows the piping apparatus (Example 2) of 7th Embodiment, The figure (A) is a structure explanatory drawing, The same figure (B) is an effect | action explanatory drawing. It is sectional drawing which shows the piping apparatus (Example 1) of 8th Embodiment, The figure (A) is a structure explanatory drawing, The same figure (B) is an effect | action explanatory drawing. It is sectional drawing which shows the piping apparatus (Example 2) of 8th Embodiment, The figure (A) is a structure explanatory drawing, The same figure (B) is an effect | action explanatory drawing. It is sectional drawing which shows the piping apparatus (Example 1) of 9th Embodiment, The figure (A) is a structure explanatory drawing, The figure (B) is an effect | action explanatory drawing. It is sectional drawing which shows the piping apparatus (Example 2) of 9th Embodiment, The figure (A) is a structure explanatory drawing, The same figure (B) is an effect | action explanatory drawing. It is the schematic which shows the general bearing lubricating oil system | strain of the conventional power plant, The figure (A) is the whole figure, The figure (B) is the a arrow view. The figure which shows the state of the pipe | tube obstruction | occlusion which may generate | occur | produce when the return oil (branch) Lhb from each bearing part merges into the mother pipe 11 during plant operation in the said bearing lubricating oil system.

  Embodiments of the present invention will be described below with reference to the drawings.

(First embodiment)
1A and 1B are cross-sectional views showing a piping device according to the first embodiment, in which FIG. 1A is a configuration explanatory view and FIG. 1B is an operation explanatory view.

  A return oil branch pipe 12 is connected from above to a return oil mother pipe 11 arranged at a downward gradient θ.

  Return oil Lha flows into the return oil mother pipe 11 as shown by an arrow a, and return oil Lhb from the bearing portion flows into the return oil branch pipe 12 as shown by an arrow b into the return oil mother pipe 11. It is configured to merge.

  And the upper wall surface inside the return oil mother pipe 11 from the upstream side to the downstream side of the connection part (the junction part of the return oils Lha and Lhb) with the return oil branch pipe 12 inside the return oil mother pipe 11 An internal bypass pipe 13 is provided along the line.

  The internal bypass pipe 13 has a function of independently communicating the gas phase space on the upstream side and the gas phase space on the downstream side of the return oil merging portion inside the return oil mother pipe 11.

  That is, according to the piping apparatus provided with the internal bypass pipe 13 having the above-described configuration, the liquid level of the joining portion of the return oils Lha and Lhb reaches the upper wall surface of the return oil mother pipe 11 due to the partial stagnation. Even in this case, the gas phase space pressure P1 upstream, the gas phase space pressure P2 downstream, and the gas phase space pressure P3 in the return oil branch pipe 12 are maintained uniform (P1 = P2 = P3). Therefore, the diameter of the return oil mother pipe 11 can be reduced.

  Here, the length of the internal bypass pipe 13 toward the upstream side of the joining part is further upstream than the range reaching the upper wall surface of the return oil mother pipe 11 with the liquid level of the joining part rising to the maximum. The length D is set in advance.

  The piping apparatus provided with the internal bypass pipe 13 of the first embodiment can be replaced by the welded parts w1, w2, and w3 by removing the connection part between the existing return oil mother pipe 11 and the return oil branch pipe 12. You may comprise as the T joint piping 10T.

(Second Embodiment)
2A and 2B are cross-sectional views showing a piping device according to the second embodiment, in which FIG. 2A is a configuration explanatory view and FIG. 2B is an operation explanatory view.

  In the second embodiment, the inner wall ceiling surface on the upstream side of the connecting portion (the joining portion of the return oils Lha and Lhb) of the return oil mother pipe 11 with the return oil branch pipe 12, and the return oil branch pipe 12 An external bypass pipe 14 is provided to connect the inner wall surface.

  The external bypass pipe 14 communicates the gas phase space on the upstream side and the gas phase space on the downstream side of the return oil joining portion of the return oil mother pipe 11 via the gas phase space of the return oil branch pipe 12. Has the function of

  That is, according to the piping apparatus provided with the external bypass pipe 14 having the above-described configuration, the liquid level of the joining portion of the return oils Lha and Lhb is caused by the partial stagnation as in the first embodiment. Even when reaching the upper wall surface of the pipe 11, the gas phase space pressure P 1 on the upstream side of the junction, the gas phase space pressure P 2 on the downstream side, and the gas phase space pressure P 3 in the return oil branch pipe 12 are uniform. (P1 = P2 = P3) can be maintained, and the diameter of the return oil mother pipe 11 can be reduced.

  Here, in the return oil mother pipe 11, the length to the upstream side of the junction where the one end of the external bypass pipe 14 is connected is set to a length D set in advance under the same conditions as in the first embodiment.

  In addition, you may comprise the piping apparatus provided with the external bypass pipe 14 of this 2nd Embodiment as T joint piping 10T replaceable by welding part w1, w2, w3 similarly to the said 1st Embodiment.

  FIG. 3 is a cross-sectional view showing another example of the piping device of the second embodiment.

  In another embodiment, the connection portion (opening) of the external bypass pipe 14 in the return oil branch pipe 12 is configured as an elbow pipe 14e that faces downward along the inner wall of the return oil branch pipe 12. Alternatively, a return oil guard 14g is provided on the inner wall of the return oil branch pipe 12 directly above the connection portion (opening) of the external bypass pipe 14.

  According to this, it is possible to prevent the return oil Lhb flowing freely falling in the return oil branch pipe 12 from blocking the opening of the external bypass pipe 14.

(Third embodiment)
FIG. 4 is a cross-sectional view showing a piping device according to a third embodiment, where FIG. 4A is a configuration explanatory diagram and FIG. 4B is an operation explanatory diagram.

  In the third embodiment, between the inner wall ceiling surface on the upstream side and the ceiling wall surface on the downstream side of the connecting portion of the return oil mother pipe 11 with the return oil branch pipe 12 (the junction of the return oils Lha and Lhb). An external bypass pipe 15 is provided.

  The external bypass pipe 15 has a function of independently communicating the gas phase space on the upstream side and the gas phase space on the downstream side of the return oil merging portion via the outside of the return oil mother pipe 11.

  That is, according to the piping apparatus provided with the external bypass pipe 15 having the above-described configuration, the liquid level of the joining portion of the return oils Lha and Lhb is caused by the partial stagnation as in the first embodiment. Even when reaching the upper wall surface of the pipe 11, the gas phase space pressure P 1 on the upstream side of the junction, the gas phase space pressure P 2 on the downstream side, and the gas phase space pressure P 3 in the return oil branch pipe 12 are uniform. (P1 = P2 = P3) can be maintained, and the diameter of the return oil mother pipe 11 can be reduced.

  Here, the length to the upstream side of the junction where the one end of the external bypass pipe 15 is connected in the return oil mother pipe 11 is set to a length D set in advance under the same conditions as in the first embodiment.

  In addition, you may comprise the piping apparatus which provided the external bypass pipe 15 of this 3rd Embodiment as T joint piping 10T replaceable by welding part w1, w2, w3 similarly to the said each embodiment.

(Fourth embodiment)
FIGS. 5A and 5B are cross-sectional views showing a piping device according to a fourth embodiment. FIG. 5A is a configuration explanatory view and FIG. 5B is an operation explanatory view.

  In the fourth embodiment, the inner wall ceiling surface on the upstream side of the connecting portion (the joining portion of the return oils Lha and Lhb) with the return oil branch pipe 12 in the return oil mother pipe 11, and the return oil branch pipe 12 A first external bypass pipe 16a is provided to connect between one inner wall surface and the downstream inner wall ceiling surface of the return oil mother pipe 11 is connected to the other inner wall surface of the return oil branch pipe 12. A second external bypass pipe 16b is provided.

  The first external bypass pipe 16a has a function of communicating a gas phase space upstream of the return oil merging portion of the return oil mother pipe 11 and a gas phase space of the return oil branch pipe 12, The second external bypass pipe 16 b has a function of communicating the gas phase space of the return oil branch pipe 12 with the gas phase space on the downstream side of the return oil merging portion of the return oil mother pipe 11.

  That is, according to the piping apparatus provided with the first and second external bypass pipes 16a and 16b having the above-described configuration, the return oil mother pipe 11 is caused by the partial stagnation of the liquid level at the junction of the return oils Lha and Lhb. Even when the opening of the connecting portion with the return oil branch pipe 12 is closed, the gas phase space pressure P1 on the upstream side of the joining portion in the return oil mother pipe 11 and the gas pressure on the downstream side The phase space pressure P2 and the gas phase space pressure P3 in the return oil branch pipe 12 can be maintained uniform (P1 = P2 = P3), and the diameter of the return oil mother pipe 11 can be reduced. Become.

  Here, in the return oil mother pipe 11, the length to the upstream side of the joining portion that connects one end of the first external bypass pipe 16a is a length D set in advance under the same conditions as in the first embodiment. To do.

  In addition, the piping apparatus provided with the first and second external bypass pipes 16a and 16b of the fourth embodiment is also a T-joint pipe 10T that can be replaced by the welds w1, w2, and w3, as in the above embodiments. It may be configured.

  As another example of the fourth embodiment, the first and second external bypass pipes 16a in the return oil branch pipe 12 are the same as the other examples (see FIG. 3) of the second embodiment. , 16b are configured as elbow pipes 14e that face downward along the inner wall of the return oil branch pipe 12, or the first and second external parts of the return oil branch pipe 12 You may comprise the return oil guard 14g in the inner wall immediately above each connection part (opening part) of the bypass pipes 16a and 16b.

(Fifth embodiment)
FIG. 6 is a cross-sectional view showing a piping device according to a fifth embodiment. FIG. 6A is a configuration explanatory view, and FIG. 6B is an operation explanatory view.

  In the fifth embodiment, the connection from the ceiling wall surface on the upstream side of the return oil mother pipe 11 at the connection part between the return oil mother pipe 11 and the return oil branch pipe 12 (joint part of the return oils Lha and Lhb). The first internal bypass pipe 17a is provided (along) along the side wall surface of the return oil branch pipe 12 bent at the portion, and bent at the connection portion from the ceiling wall surface on the downstream side of the return oil mother pipe 11 A second internal bypass pipe 17 a is provided along (in line with) the side wall surface of the return oil branch pipe 12.

  The first internal bypass pipe 17a has a function of communicating a gas phase space on the upstream side of the return oil merging portion of the return oil mother pipe 11 with a gas phase space of the return oil branch pipe 12, and The second internal bypass pipe 17 b has a function of communicating the gas phase space of the return oil branch pipe 12 with the gas phase space on the downstream side of the return oil merging portion of the return oil mother pipe 11.

  That is, according to the piping device provided with the first and second internal bypass pipes 17a and 17b having the above-described configuration, the return oil mother pipe 11 is caused by the partial stagnation of the liquid level at the junction of the return oils Lha and Lhb. The gas phase space pressure P1 on the upstream side of the joining portion, the gas phase space pressure P2 on the downstream side, and the gas phase space pressure P3 in the return oil branch pipe 12 are It can be kept uniform (P1 = P2 = P3), and the diameter of the return oil mother pipe 11 can be reduced.

  Here, in the return oil mother pipe 11, the length of the first internal bypass pipe 17a to the upstream side of the merging portion is set to a length D set in advance under the same conditions as in the first embodiment.

  In addition, the piping device provided with the first and second internal bypass pipes 17a and 17b of the fifth embodiment is also a T-joint pipe 10T that can be replaced by the welded parts w1, w2, and w3, as in the above embodiments. It may be configured.

  As another example of the fifth embodiment, the first and second internal bypass pipes 17a in the return oil branch pipe 12 are the same as other examples (see FIG. 3) of the second embodiment. , 17b may be provided with a return oil guard 14g immediately above each opening.

(Sixth embodiment)
FIG. 7A is a cross-sectional view showing a piping device (Example 1) of a sixth embodiment, where FIG. 7A is a configuration explanatory view, and FIG. 7B is an operation explanatory view.

  FIG. 7B is a cross-sectional view showing the piping device (Example 2) of the sixth embodiment, where FIG. 7A is a configuration explanatory view, and FIG. 7B is an operation explanatory view.

  In this sixth embodiment, a first eccentric reducer (in which the diameter of the connecting portion of the return oil mother pipe 11 with the return oil branch pipe 12 (the junction of the return oils Lha and Lhb) is expanded on the upstream side ( A second eccentric reducer (eccentric pipe joint) 18a that uses the eccentric pipe joint 18a on the downstream side and returns the expanded diameter to the original is used, and an enlarged pipe 19T having only the diameter in between is expanded.

  That is, according to the piping device in which the connection portion is configured by the expansion pipe 19T, the liquid in the junction portion of the return oils Lha and Lhb is expanded by expanding only the diameter of the connection portion (the junction portion of the return oils Lha and Lhb). Even if the surface rises to the upper wall surface level of the return oil mother pipe 11 due to the partial stagnation, the gas phase space in the junction can be maintained, and the upstream side of the junction in the return oil mother pipe 11 can be maintained. The gas phase space pressure P1, the downstream gas phase space pressure P2, and the gas phase space pressure P3 in the return oil branch pipe 12 can be maintained uniformly (P1 = P2 = P3). Therefore, the diameter of the return oil mother pipe 11 can be reduced.

  In addition, the piping device including the reducers 18a and 18b in which the connecting portion of the sixth embodiment is an enlarged tube 19T is also used as a T-joint piping 20T that can be replaced by the welded portions w1, w2, and w3, as in the above embodiments. It may be configured.

(Seventh embodiment)
FIG. 8A is a cross-sectional view showing a piping device (Example 1) of a seventh embodiment, where FIG. 8A is a configuration explanatory view and FIG. 8B is an operation explanatory view.

  FIG. 8B is a cross-sectional view showing a piping device (Example 2) according to the seventh embodiment, where FIG. 8A is a configuration explanatory view and FIG. 8B is an operation explanatory view.

  In the seventh embodiment, an eccentric reducer (eccentric pipe) that expands the diameter of the pipe of the connecting part (the joining part of the return oils Lha and Lhb) of the return oil mother pipe 11 with the return oil branch pipe 12 on the upstream side thereof. The joint 18a is used as an enlarged pipe 19T having an enlarged diameter, and the downstream side of the enlarged pipe 19T is formed as a return oil mother pipe 11L having the same diameter.

  That is, according to the piping device having an enlarged diameter after the connecting portion, the liquid level of the joining portion of the return oils Lha and Lhb rises to the upper wall surface level of the return oil mother pipe 11 due to the partial stagnation. Further, the gas phase space in the junction can be maintained. In the return oil mother pipes 11 to 11L, the gas phase space pressure P1 on the upstream side of the junction, the gas phase space pressure P2 on the downstream side, and the return oil branch pipe. 12 and the gas phase space pressure P3 can be kept uniform (P1 = P2 = P3). Therefore, the diameter of the return oil mother pipe 11 can be reduced.

  In addition, since the amount of oil is increased by the merging of the return oils Lha and Lhb after the connecting part (merging part), even if there is a similar connecting part (merging part) further downstream, the returning oil Lha (+ Lhb) , ...)

  In addition, the piping device including the reducer 18a in which the connecting portion of the seventh embodiment is an enlarged tube 19T is also configured as a T-joint piping 20T that can be replaced by the welded portions w1, w2, and w3, as in the above embodiments. May be.

(Eighth embodiment)
FIG. 9A is a cross-sectional view showing a piping device (Example 1) according to an eighth embodiment. FIG. 9A is a configuration explanatory view, and FIG. 9B is an operation explanatory view.

  FIG. 9B is a cross-sectional view showing a piping device (Example 2) of the eighth embodiment, where FIG. 9A is a configuration explanatory view, and FIG. 9B is an operation explanatory view.

  In the eighth embodiment, the pipe of the connecting part (the joining part of the return oils Lha and Lhb) between the return oil mother pipe 11 and the return oil branch pipe 12 is arranged upstream of the connecting part (joining part) in the branch pipe 12. Thus, an eccentric reducer (eccentric pipe joint) 21 that is eccentric in the upstream direction of the mother pipe 11 to widen the diameter is used, and an enlarged pipe 19T ′ having an enlarged diameter at the end of the branch pipe 12 is configured.

  That is, according to the piping device in which the connecting portion is configured by the enlarged pipe 19T ′, only the diameter of the connecting portion (the joining portion of the return oils Lha and Lhb) on the branch pipe 12 side is expanded in the upstream direction of the mother pipe 12. Thus, even if the liquid level of the joining portion of the return oils Lha and Lhb rises to the upper wall surface level of the return oil mother pipe 11 due to the partial stagnation, the gas phase space in the joining portion can be maintained. In the return oil mother pipe 11, the gas phase space pressure P1 on the upstream side of the joining portion, the gas phase space pressure P2 on the downstream side, and the gas phase space pressure P3 in the return oil branch pipe 12 are uniform (P1 = P2 = P3). ) Can be maintained. Therefore, the diameter of the return oil mother pipe 11 can be reduced.

  In addition, the piping device including the reducer 21 in which the connecting portion of the eighth embodiment is an enlarged tube 19T ′ is also configured as a T-joint piping 20T that can be replaced by the welded portions w1, w2, and w3, as in the above embodiments. May be.

(Ninth embodiment)
FIG. 10A is a cross-sectional view showing a piping device (Example 1) according to a ninth embodiment, where FIG. 10A is a configuration explanatory view and FIG. 10B is an operation explanatory view.

  FIG. 10B is a cross-sectional view showing the piping device (Example 2) of the ninth embodiment, where FIG. 10A is a configuration explanatory view and FIG. 10B is an operation explanatory view.

  In the ninth embodiment, the pipe of the connecting portion of the return oil mother pipe 11 with the return oil branch pipe 12 (the junction of the return oils Lha and Lhb) is decentered downward on the upstream side to widen the diameter. An eccentric reducer (eccentric pipe joint) 22 is used to form an enlarged pipe 19T having an enlarged diameter, and a downstream side of the enlarged pipe 19T is formed as a return oil mother pipe 11L having the same diameter.

  That is, according to the piping device having an enlarged diameter after the connecting portion, even if the liquid level of the joining portion of the return oils Lha and Lhb rises to the diameter level of the return oil mother pipe 11 due to the partial stagnation. The gas phase space in the junction can be maintained, and the gas phase space pressure P1 on the upstream side of the junction, the gas phase space pressure P2 on the downstream side, and the return oil branch pipe 12 in the return oil mother pipes 11 to 11L. The gas phase space pressure P3 can be kept uniform (P1 = P2 = P3). Therefore, the diameter of the return oil mother pipe 11 can be reduced.

  Moreover, since the diameter of the connecting portion (merging portion) and thereafter is deviated downward and the diameter is enlarged, not only can the risk of blockage in the pipe due to the merging be prevented more effectively, but also a similar connecting portion on the downstream side. Even when the (merging portion) continues, the return oil Lha (+ Lhb,...) Whose oil amount has increased due to the merging can be made to flow more smoothly.

  In addition, the piping device including the reducer 22 in which the connecting portion of the ninth embodiment is an enlarged pipe 19T is also configured as a T-joint piping 20T that can be replaced by the welded portions w1, w2, and w3, as in the above embodiments. May be.

  Therefore, according to the piping apparatus (T-joint piping) of the first to ninth embodiments having the above-described configuration, the liquid flowing in the inclined main pipe and the branch pipe connected to the main pipe from above are provided. Even if the liquid level rises due to a partial stagnation of the merged liquid at the junction with the flowing liquid, the gas phase space on the upstream side of the mother pipe, the gas phase space on the downstream side, and the gas phase space on the upstream side of the branch pipe Can be maintained, and each space pressure can be maintained uniformly (P1 = P2 = P3).

  Therefore, it is possible to minimize the diameter of the piping while preventing the gas phase space on the upstream side of the main pipe and the gas phase space on the downstream side from being closed, and the power plant can be made compact and constructed. Costs can be reduced.

  In addition, although the piping apparatus of each said embodiment was demonstrated as a piping apparatus used for the bearing lubricating oil system | strain of a power plant, it is not restricted to the said power generation plant, While making the liquid from the branch pipe 12 join the inclined mother pipe 11 If it is a piping system that flows and it is indispensable to always maintain the gas phase space in the entire pipe, it can be used in the same manner as in the above embodiments to obtain the same effect.

  The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention when it is practiced. Further, each of the embodiments includes inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if some constituent elements are deleted from all the constituent elements shown in each embodiment or some constituent elements are combined in different forms, the problems described in the column of the problem to be solved by the invention If the effects described in the column “Effects of the Invention” can be obtained, a configuration in which these constituent requirements are deleted or combined can be extracted as an invention.

10T ... T joint piping, Lha, Lhb ... return oil, w1 to w3 ... welded part, 11 ... return oil mother pipe, 11L ... enlarged return oil mother pipe, 12 ... return oil branch pipe, 13 ... internal bypass pipe, 14, 15 ... External bypass pipe, 14e ... Elbow pipe, 14g ... Return oil guard, 15 ... External,
16a, 16b ... first and second external bypass pipes, 17a, 17b ... first and second internal bypass pipes, 18a, 18b ... first and second eccentric reducers, 19T ... (mother pipe) expansion pipe, 19T '... (Branch tube) Expanded tube.

Claims (10)

A mother pipe for flowing liquid in a state of being disposed at an angle and having a gas phase space;
A branch pipe connected to the mother pipe from above, allowing a liquid to flow in a state having a gas phase space, and joining the liquid to the liquid flowing in the mother pipe;
Piping means for always communicating the gas phase space on the upstream side and the gas phase space on the downstream side with respect to the liquid confluence portion by the mother pipe and the branch pipe;
A piping device characterized by comprising: The piping means is provided along an upper part of the pipe between the upstream side and the downstream side of the joining portion of the liquid in the mother pipe, and a gas phase space on the upstream side and a gas phase space on the downstream side from the joining portion. Is an internal bypass pipe that always communicates
The piping apparatus according to claim 1. The piping means is provided between a pipe upper portion upstream of the liquid merging portion in the mother pipe and a pipe wall upstream of the liquid merging portion in the branch pipe, and from the merging portion of the mother pipe It is an external bypass pipe that always communicates the gas phase space on the upstream side and the gas phase space on the downstream side via the pipe internal space of the branch pipe,
The piping apparatus according to claim 1. The piping means is provided between a pipe on the upstream side and a pipe on the downstream side of the joining part of the liquid in the mother pipe, and connects the gas phase space on the upstream side and the gas phase space on the downstream side with respect to the joining part. It is an external bypass pipe that always communicates.
The piping apparatus according to claim 1. The piping means is
A first external bypass pipe provided between a pipe upper part upstream of the liquid confluence part in the mother pipe and a pipe wall upstream of the liquid confluence part in the branch pipe;
A second external bypass pipe provided between a pipe upper portion on the downstream side of the liquid junction in the mother pipe and a pipe wall on the upstream side of the liquid junction in the branch pipe;
The gas phase space on the upstream side and the gas phase space on the downstream side from the joining portion of the mother pipe are always in communication with each other via the pipe internal space of the branch pipe.
The piping apparatus according to claim 1. The piping means is
A first internal bypass pipe provided between a pipe upper portion upstream of the liquid confluence portion in the mother pipe and a pipe inner wall upstream of the liquid confluence portion in the branch pipe;
A second internal bypass pipe provided between a pipe upper part on the downstream side of the liquid junction in the mother pipe and a pipe inner wall on the upstream side of the liquid junction in the branch pipe;
The gas phase space on the upstream side and the gas phase space on the downstream side from the joining portion of the mother pipe are always in communication with each other via the pipe internal space of the branch pipe.
The piping apparatus according to claim 1.   The piping means has an enlarged pipe in which the diameter of the mother pipe is larger than the diameter of the upstream side at the joining part of the liquid at the connection part between the mother pipe and the branch pipe, and from the joining part of the liquid The piping device according to claim 1, wherein the upstream gas phase space and the downstream gas phase space are always in communication.   The pipe means is an enlarged pipe in which the diameter of the branch pipe is decentered in the upstream direction from the upstream diameter of the branch pipe at the junction of the liquid at the connection portion of the mother pipe and the branch pipe. The piping apparatus according to claim 1, wherein a gas phase space on the upstream side and a gas phase space on the downstream side of the junction portion of the liquid are always in communication with each other.   The piping means has an enlarged pipe in which the diameter of the mother pipe is decentered downward from the diameter on the upstream side at the junction of the liquid at the connection part between the mother pipe and the branch pipe, 8. The piping apparatus according to claim 7, wherein the gas phase space on the upstream side and the gas phase space on the downstream side with respect to the liquid junction are in constant communication.   The said pipe | tube, branch pipe, and a piping means are used for the bearing lubricating oil system | strain of a power plant, The said gaseous-phase space is maintained at a negative pressure, The any one of Claim 1 thru | or 9 characterized by the above-mentioned. The piping apparatus according to the item.