Gas Governor

Abstract

To provide a gas governor capable of finely adjusting the venturi effect without depending on the dimensional tolerance of the venturi shape. [Solution] Changes in the gas flow rate in the downstream conduit R2 are detected as pressure changes, and an auxiliary pressure P3 is generated that is lower than the secondary pressure P2 by the amount of the negative pressure. The auxiliary diaphragm pressure chamber AS faces the pilot spring n1 of the pilot governor 3 and assists the force that opens and closes the pilot valve. The connecting conduit Z includes a main line Z1 that connects the secondary orifice W and the auxiliary diaphragm pressure chamber, and a sub-line Z2 that is a downstream conduit that connects the auxiliary diaphragm pressure chamber to the upstream or downstream side of the secondary orifice W. The main line and sub-line are provided with variable throttles v1 and v2, respectively. The internal pressure of the auxiliary diaphragm pressure chamber is a mixed pressure P2' of the auxiliary pressure of the gas passing through the main line and the secondary pressure of the gas passing through the sub-line.

Description

[Technical Field]

[0001] The present invention relates to a gas governor (also called a gas pressure regulator) that reduces the pressure of gas (such as city gas) transported from the upstream side at a primary pressure to a secondary pressure and supplies it to the downstream side. [Background technology]

[0002] Conventional gas governors have been widely used to maintain a stable gas supply, mainly in city gas supply and industrial gas supply systems. Its basic function is to control the gas pressure within a predetermined range and to achieve safe and efficient gas supply. A typical gas governor is equipped with a valve mechanism to adjust pressure and various sensors and actuators to manage the gas flow rate.

[0003] Furthermore, conventional gas governors have undergone various technological improvements depending on the environment and type of gas used. In particular, in city gas supply systems, there is a demand for technology that can quickly respond to fluctuations on the supply and user sides while maintaining stable pressure control.

[0004] For this reason, highly sensitive control mechanisms and adjustment functions have been added to improve responsiveness to pressure fluctuations, and pilot-type governors have become mainstream in recent years. Pilot-type governors use a sub-control valve to fine-tune the pressure before the main control valve, enabling highly accurate pressure control.

[0005] Regarding the above pilot-type governor, the inventors of the present invention have invented a gas governor described in Patent Document 1.

[0006] The gas governor described in Patent Document 1 is a gas governor equipped with a pilot governor, and a secondary orifice (venturi) is arranged in a pipe downstream of the governor body. In addition, an auxiliary diaphragm pressure chamber is installed in the pilot governor, which applies the pressure of the gas decompressed in the venturi section and, together with the downstream secondary pressure, opposes the pilot spring, thereby assisting in the force that opens and closes the pilot valve. Furthermore, a restriction and a tank are provided in the pipe connecting the auxiliary diaphragm pressure chamber and the venturi, which function by mitigating the effects of fluctuations in secondary pressure that occur in the venturi section so that they do not suddenly act on the auxiliary diaphragm pressure chamber.

[0007] This makes it possible to detect not only changes in the secondary pressure but also an increase in the flow rate of the gas that is reduced to the secondary pressure and flowed downstream, and to control the control pressure. This allows for increased responsiveness of the control pressure to increases in flow rate, reduces offset, and allows for stable control of the control pressure, thereby suppressing vibration and flapping.

[0008] The offset is a phenomenon in which the secondary pressure drops below the set pressure as the flow rate increases. Recently, the gas governor described in Patent Document 1 has been designed to suppress offset by providing a venturi in the pipe downstream of the governor body, as described above.

[0009] That is, by providing the venturi, the secondary pressure generated in the venturi portion decreases as the flow rate increases. Furthermore, the reduction in secondary pressure in the venturi portion causes the diaphragm in the auxiliary diaphragm pressure chamber to lower, opening the pilot valve, thereby reducing the control pressure on the sleeve of the governor body. Then, as the control pressure decreases, the sleeve expands, increasing the gas flow rate through the governor body (AFV), resulting in an increase in outlet pressure (pressure downstream of the venturi). Hereinafter, the above-described series of steps resulting from the provision of a venturi will be referred to as the "venturi effect." [Prior art documents] [Patent documents]

[0010] [Patent Document 1] Patent No. 5698545 Summary of the Invention [Problem to be solved by the invention]

[0011] However, even the gas governor described in Patent Document 1 still has the following problems.

[0012] That is, the venturi installed in the downstream pipe is intended to detect an increase in the downstream gas flow rate and mitigate the occurrence of offset, but the degree of this mitigation depends on the venturi shape. Therefore, due to dimensional tolerances of the venturi shape, etc., there are individual differences in the degree of the above-mentioned venturi effect. Furthermore, since the venturi shape cannot be easily changed, increasing the maximum flow rate can result in an increase in secondary pressure more than necessary, making adjustment difficult.

[0013] The present invention has been made in view of the above-described circumstances, and an object of the present invention is to provide a gas governor that allows fine adjustment of the Venturi effect without depending on the dimensional tolerance of the Venturi shape, etc. [Means for solving the problem]

[0014] To achieve this object, the present disclosure provides gas governors [1] to [4].

[0015] [1] A governor body is installed in the pipeline and reduces the gas transported from the upstream side at primary pressure to secondary pressure and flows it downstream. a pilot loop provided with a restrictor for generating a control pressure for controlling the operation of the governor body, the pilot loop being connected between an upstream conduit and a downstream conduit of the governor body; a pilot governor that is installed in the pilot loop, opens and closes a pilot valve in response to a secondary pressure of the gas, controls the amount of the gas passing through the pilot loop, and is configured to be able to perform feedback control of the governor body so that the secondary pressure is kept constant; Equipped with a gas governor that reduces the pressure of the gas supplied from an upstream side and supplies the reduced pressure to a downstream side by changing a valve opening of the governor body using the control pressure controlled by the pilot governor, a secondary orifice disposed in the downstream conduit; an auxiliary diaphragm pressure chamber included in the pilot governor and configured to control the degree of opening or closing of the pilot valve in accordance with an internal pressure thereof; and a connecting conduit connecting the auxiliary diaphragm pressure chamber and the downstream conduit, the secondary orifice generates a negative pressure based on the flow of gas in the downstream conduit, detects a change in the flow rate of gas in the downstream conduit as a pressure change, and generates an auxiliary pressure that is lower than the secondary pressure by an amount corresponding to the negative pressure; the auxiliary diaphragm pressure chamber faces a pilot spring of the pilot governor to assist the force that opens and closes the pilot valve; the connecting pipe line includes a main line connecting the secondary orifice and the auxiliary diaphragm pressure chamber, and a sub-line that is the downstream pipe line and connects the auxiliary diaphragm pressure chamber to an upstream side or downstream side of the secondary orifice, The main line and the sub-line are each provided with a variable throttle, the internal pressure of the auxiliary diaphragm pressure chamber is a mixed pressure of the auxiliary pressure of the gas passing through the main line and the secondary pressure of the gas passing through the sub-line. Gas governor.

[0016] [2] the sub-line connects the downstream pipe line upstream of the secondary orifice to the auxiliary diaphragm pressure chamber; [1] The gas governor according to the present invention.

[0017] [3] the sub-line connects the downstream pipe line and the auxiliary diaphragm pressure chamber via the main line; [1] or [2]. The gas governor according to [1] or [2].

[0018] [4] The variable throttle is a needle valve. The gas governor according to any one of [1] to [3]. [Effects of the Invention]

[0019] According to the present invention, it is possible to provide a gas governor that allows fine adjustment of the Venturi effect without depending on the dimensional tolerance of the Venturi shape, etc. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 1 is a principle diagram showing an embodiment in which the present invention is applied to an axial flow governor. [Figure 2] 10 is a graph showing the relationship between the gas flow rate and the outlet pressure according to the degree of throttling of the main line and the sub-line in an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0021] A gas governor according to an embodiment of the present invention will be described below with reference to FIGS. 1 and 2. FIG. The following embodiment is an example of the present invention, and the present invention is not limited to the following embodiment. In these figures, the symbol X indicates the gas governor according to this embodiment.

[0022] <Configuration> As shown in FIG. 1, the gas governor X includes a governor body 1, a pilot loop 2, and a pilot governor 3. In addition, the gas governor X reduces the pressure of the gas supplied from the upstream side and supplies it downstream by changing the valve opening of the governor body 1 using the control pressure Pc controlled by the pilot governor 3.

[0023] The governor body 1 is an axial flow governor (hereinafter referred to as AFV) that is installed midway in a pipeline and reduces the pressure of gas transported from the upstream side at a primary pressure P1 to a secondary pressure P2 and flows it downstream.

[0024] The AFV used in this embodiment has a schematic structure, as shown in Figure 1, which includes a pair of truncated cone-shaped closures 11 with multiple slits on their circumferential surfaces, a rubber sleeve 12 that closes the slits in the closures 11, and a cylindrical valve body 13 that houses these, and is similar in configuration to AFVs that are currently in widespread use. In addition, the AFV applies a control pressure Pc to the space between the sleeve 12 and the valve body 13, causing the sleeve 12 to open and close the slits of a pair of closures 11, which are connected facing each other to form an hourglass shape.

[0025] The pilot loop 2 is provided with a restrictor K that generates a control pressure Pc that controls the operation of the governor body 1, and is a pipe line connected between the upstream pipe line R1 and the downstream pipe line R2 of the governor body 1 so as to bypass the governor body 1. In the present invention, the term restrictor is used to include a venturi.

[0026] The pilot governor 3 is installed in the pilot loop 2 and opens and closes the pilot valve V in response to the secondary gas pressure P2, thereby controlling the amount of gas passing through the pilot loop 2 and varying the control pressure Pc of the sleeve 12 that closes the closure 11 of the governor body 1. As a result, the pilot governor 3 is configured to be able to feedback control the governor body 1 so that the secondary pressure P2 is kept constant.

[0027] The pilot governor 3 has a housing H whose interior is partitioned by a plurality of diaphragms D1 to D3 and partition walls, thereby defining a first diaphragm pressure chamber S1 to a fourth diaphragm pressure chamber S4 and an auxiliary diaphragm pressure chamber AS.

[0028] The first diaphragm pressure chamber S1 is a space that houses a pilot spring n1 and is open to the atmosphere. The second diaphragm pressure chamber S2 is a space to which the pilot loop 2 is connected and in which a pilot valve V that opens and closes the pilot loop 2 is built-in. The third diaphragm pressure chamber S3 is a space that accommodates a return spring n2 that applies a force opposing the pilot spring n1, and to which a secondary pressure P2 is applied via a branch pipe m of the pilot loop 2. The fourth diaphragm pressure chamber S4 is a space in which atmospheric pressure is applied to the diaphragm D3 of the third diaphragm pressure chamber S3.

[0029] The auxiliary diaphragm pressure chamber AS is a space to which a mixed pressure P2' of an auxiliary pressure P3 reduced in pressure by a secondary orifice W (described later) and the secondary pressure P2 acts.

[0030] To go into more detail about the relationship between each diaphragm pressure chamber S1 to S4 and the auxiliary diaphragm pressure chamber AS, diaphragms D1, D2 and D3 are respectively arranged between the first diaphragm pressure chamber S1 and the second diaphragm pressure chamber S2, between the second diaphragm pressure chamber S2 and the auxiliary diaphragm pressure chamber AS, and between the fourth diaphragm pressure chamber S4 and the third diaphragm pressure chamber S3.

[0031] As a result, the chambers are partitioned so that the differential pressure between the diaphragm pressure chambers S1, S2, S3, S4 and the auxiliary diaphragm pressure chamber AS acts on the diaphragms D1, D2, and D3.

[0032] In addition, the auxiliary diaphragm pressure chamber AS and the fourth diaphragm pressure chamber S4 are separated by a partition wall that is part of the housing H, and the differential pressure between the auxiliary diaphragm pressure chamber AS and the fourth diaphragm pressure chamber S4 is configured so as not to affect the opening and closing of the pilot valve V. Diaphragms D1 and D2, and diaphragms D2 and D3 are connected by connecting rods j1 and j2, respectively, and all diaphragms D1 to D3 are arranged to work together and the differential pressures acting on the respective diaphragms D1 to D3 affect each other.

[0033] Furthermore, a pilot valve V that opens and closes the pilot loop 2 is built into the second diaphragm pressure chamber S2 connected to the pilot loop 2. Like a general valve, the pilot valve V is composed of a valve body (not shown) attached to the connecting rod j1 and a valve seat (not shown) molded on the housing H side.

[0034] As a result, when the secondary pressure P2 drops below the set pressure, the connecting rods j1 and j2 move in conjunction with the deformation of all diaphragms D1 to D3, causing the valve disc attached to connecting rod j1 to separate from the valve seat on the housing side of pilot valve V, opening the valve.

[0035] When the pilot valve V is opened as described above, some of the gas upstream of the governor body 1 flows into the pilot loop 2, passes through the second diaphragm pressure chamber S2 of the pilot governor 3, and is discharged into the downstream pipe R2. At this time, a pressure change (decompression) occurs in the restrictor K due to the flow of gas, and this pressure change becomes a control pressure Pc that opens and closes the governor body 1, and acts on the governor body 1 via the branch pipe m.

[0036] The set pressure of the pilot governor 3 is determined by a pilot spring n1. More specifically, the difference between the spring force of the pilot spring n1 and the spring force of the return spring n2 determines the set pressure. Therefore, the operator can adjust the set pressure by appropriately tightening or loosening the pilot spring n1 using the adjustment screw s.

[0037] Here, the gas governor X has a secondary orifice W disposed in the downstream pipe line R2, and a connecting pipe line Z that connects the auxiliary diaphragm pressure chamber AS and the downstream pipe line R2.

[0038] The secondary orifice W detects a change in the gas flow rate in the downstream conduit R2 as a change in pressure, and in this embodiment, for example, is configured by connecting a venturi to the downstream conduit R2. The secondary orifice W detects an auxiliary pressure P3, which is the gas pressure at the smallest diameter part of the venturi that occurs when gas flows in the downstream conduit R2, as an indication of a change in the gas flow rate. That is, the auxiliary pressure P3 (=P2-ΔPv) downstream of the secondary orifice W provided in the downstream conduit R2 is detected as an indication of a change in the gas flow rate. In the present invention, the term "secondary orifice" is used to include a venturi.

[0039] The connecting pipe line Z includes a main line Z1 that connects the secondary orifice W and the auxiliary diaphragm pressure chamber AS, and a sub-line Z2 that connects the downstream pipe line R2 upstream of the secondary orifice W and the auxiliary diaphragm pressure chamber AS.

[0040] As described above, gas having the auxiliary pressure P3 extracted from the secondary orifice W passes through the main line Z1. Gas having a secondary pressure P2 inside the downstream pipe R2 passes through the sub-line Z2. The auxiliary pressure P3 is the same as the secondary pressure P2 when there is no flow, but when there is flow, a pressure difference of ΔPv occurs, and P3 = P2 - ΔPv.

[0041] As a result, the auxiliary diaphragm pressure chamber AS is subjected to a mixed pressure P2' (P2>P2'>P3) of the auxiliary pressure P3 (=P2-ΔPv) from the main line Z1 and the secondary pressure P2 from the sub-line Z2. This makes it possible to suppress the occurrence of offset, that is, the decrease in outlet pressure (secondary pressure P2 downstream of secondary orifice W).

[0042] More specifically, first, when the flow rate increases, the auxiliary pressure P3 decreases due to the pressure difference ΔPv, as described above. The differential pressure between the secondary pressure P2 and the auxiliary pressure P3 is proportional to the square of the flow rate, and the auxiliary pressure P3 decreases as the flow rate increases. As a result, the mixing pressure P2' also decreases.

[0043] Next, as the mixed pressure P2' in the auxiliary diaphragm pressure chamber AS decreases, the valve element is pressed down by the pilot spring n1 via the connecting rod j1 and the diaphragm D2.

[0044] Next, the valve element moves down, increasing the opening of the pilot valve V, and the control pressure Pc flows through the inside of the pilot governor 3 (second diaphragm pressure chamber S2) to the downstream side (low pressure side). As a result, the gas flow rate passing through the pilot governor 3 and flowing downstream becomes greater than the gas flow rate passing through the restrictor K, and the control pressure Pc decreases.

[0045] Finally, the above-mentioned decrease in control pressure Pc causes the sleeve 12 of the governor body 1 to expand, allowing more gas to flow into the governor body 1 and the downstream pipe R2. This results in an increase in outlet pressure (Venturi effect).

[0046] Here, the main line Z1 and the sub-line Z2 are provided with needle valves v1 and v2 as variable throttles, respectively. The operator can check the outlet pressure by operating each of the needle valves v1 and v2.

[0047] In particular, the operator can adjust the strength of the Venturi effect by adjusting the valve opening of the main line Z1 using the needle valve v1, and the degree of mitigation of the Venturi effect by adjusting the valve opening of the sub-line Z2 using the needle valve v2. The strong Venturi effect refers to a state in which the control pressure Pc drops excessively following an excessive drop in the auxiliary pressure P3, causing the outlet pressure to rise excessively.

[0048] To elaborate on the above adjustment, if the Venturi effect is strong, the operator increases the opening of the needle valve v2, and if it is still strong, decreases the opening of the needle valve v1. If the Venturi effect is strong, the operator increases the opening of the needle valve v1, and if it is still weak, decreases the opening of the needle valve v2.

[0049] Here, the valve openings of the needle valves v1 and v2 can be calculated using the following formula: Using the assumptions shown in Equations 1 to 3, the mixture ratio (needle valve opening) shown in Equation 4 is calculated. The parameters used in each equation are as follows: Q: Gas flow rate to auxiliary diaphragm pressure chamber AS (P2') Se1: Cross-sectional area inside needle valve v1 Se2: Cross-sectional area inside needle valve v2 u1: Flow velocity inside needle valve v1 u2: Flow velocity inside needle valve v2 ρ: Density of city gas (kg / m 2 )

[0050]

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[0051]

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[0052]

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[0053]

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[0054] <Effects> According to the present embodiment as described above, the gas governor X has the following advantages.

[0055] That is, gas governor X generates a Venturi effect by providing secondary orifice W, but compared to conventional gas governors, the provision of sub-line Z2, together with main line Z1, enables fine adjustment of the Venturi effect by adjusting the valve opening using needle valves v1 and v2.

[0056] In particular, if the Venturi effect is strong and the outlet pressure rises excessively, equipment failure will occur if the pressure supplied exceeds the allowable range of the combustor or regulator to which the pressure is supplied. Recently, with the gas governor X, it is possible to generate a mixed pressure P2' such that P2 > P2' > P3 by adjusting the needle valves v1 and v2, and it is possible to prevent the pressure inside the auxiliary diaphragm pressure chamber AS from dropping excessively. As a result, it is possible to prevent equipment failures caused by an excessive increase in outlet pressure.

[0057] Furthermore, since the sub-line Z2 connects the downstream pipe line R2, which is upstream of the secondary orifice W, to the auxiliary diaphragm pressure chamber AS, the pipe line up to the secondary orifice W can be manufactured as a single product (gas governor X). That is, when the sub-line Z2 is connected downstream of the secondary orifice W, this downstream portion corresponds to various pipelines to which the gas governor X is applied, and therefore the sub-line Z2 needs to be designed according to the pipeline to which the gas governor X is applied. According to this embodiment, the gas governor X can be manufactured as a single product, including the sub-line Z2, so that the secondary orifice W can be designed and connected according to the pipeline to which it is applied, improving versatility.

[0058] Furthermore, the sub-line Z2 connects the downstream pipe R2 and the auxiliary diaphragm pressure chamber AS via the main line Z1, so that a mixed pressure P2' is generated at the end of the main line Z1. This allows the mixed pressure P2' to act more directly on the auxiliary diaphragm pressure chamber AS, thereby suppressing offset.

[0059] Furthermore, since the variable throttles are needle valves v1 and v2, the valve openings of the main line Z1 and the sub-line Z2 can be easily and precisely adjusted.

[0060] <Example> Below, using Figure 2, the gas flow rate (m 3 / h) and outlet pressure (kPa). As shown in FIG. 2, in this example, the set pressure (secondary pressure P2) is 50 kpa, the primary pressure P1 is 0.5 MPa, and the test fluid is air.

[0061] As shown in FIG. 2, when the valve opening of the main line Z1 (throttle 1) is set to 100% and the valve opening of the sub-line Z2 (throttle 2) is set to 0%, that is, in the same manner as a conventional gas governor, the outlet pressure increases as the flow rate increases.

[0062] Conversely, when the valve opening of the main line Z1 (throttle 1) is set to 0% and the valve opening of the sub-line Z2 (throttle 2) is set to 100%, the outlet pressure decreases as the flow rate increases.

[0063] Recently, by opening the main line Z1 (throttle 1) and the sub-line Z2 (throttle 2), it has been found that the outlet pressure remains stable at around the set pressure of 50 kPa, even when the flow rate increases, compared to the two examples above.

[0064] In this example, the example shown by the thick dashed line in which the valve opening of the main line Z1 (throttle 1) is 100% and the valve opening of the sub-line Z2 (throttle 2) is 10% provides the most stable outlet pressure, but the valve opening that maintains stability varies depending on the usage conditions, etc. The operator can easily change the valve opening degree of each of the main line Z1 and the sub-line Z2 by adjusting the needle valves v1 and v2.

[0065] <Example of change> The shapes and dimensions of the components shown in the above embodiment are merely examples and can be modified in various ways based on design requirements and the like.

[0066] For example, in this embodiment, an example in which the present invention is applied to an axial flow governor (AFV) has been described, but the present invention is not limited to AFVs and can be applied to pilot-type pressure regulators in general. That is, it is also applicable to a governor having a general valve structure consisting of a valve seat and a sliding valve element that opens and closes the valve seat, in which the valve element is driven by control pressure.

[0067] In addition, in this embodiment, the variable throttles provided in the main line Z1 and the sub-line Z2 are needle valves v1 and v2, but this is not limited to this and may be nozzle flappers (which have the same function as a throttle by adjusting the distance between the valve seat and the valve body) or the like.

[0068] In addition, in this embodiment, an example has been described in which a restrictor K is used as a means for reducing the pressure of gas at primary pressure P1 in the pilot loop 2 to generate control pressure Pc, but in some cases, a similar function can be achieved by using a venturi.

[0069] In addition, in this embodiment, an example has been mainly described in which the secondary orifice W is used as a means for generating the differential pressure ΔPv when a gas flow rate occurs in the downstream pipe R2, but in some cases, a similar function can be achieved by using a venturi.

[0070] In addition, in this embodiment, an example has been shown in which the sub-line Z2 is connected to the downstream pipe R2 upstream of the secondary orifice W, but it may also be connected downstream of the secondary orifice W.

[0071] In addition, in this embodiment, an example has been shown in which the sub-line Z2 connects the downstream pipe R2 and the auxiliary diaphragm pressure chamber AS via the main line Z1, but the downstream pipe R2 and the auxiliary diaphragm pressure chamber AS may also be connected directly without going through the main line Z1. [Explanation of symbols]

[0072] X Gas Governor 1 Governor body 11 Closure 12 sleeves 13 Valve body 2 Pilot Loop K Restrictor 3 Pilot Governor S1~S4 diaphragm pressure chamber D1~D3 diaphragm AS Auxiliary diaphragm pressure chamber V Pilot Valve W Secondary orifice Z Connecting pipe Z1 Main Line Z2 Subline v1, v2 needle valve P1 Primary pressure P2 Secondary pressure P2´ Mixing Pressure P3 auxiliary pressure Pc Control pressure R1 Upstream pipeline R2 Downstream pipe line

Claims

1. A governor body is installed in the pipeline and reduces the gas transported from the upstream side at primary pressure to secondary pressure and flows it downstream. a pilot loop provided with a restrictor for generating a control pressure for controlling the operation of the governor body, the pilot loop being connected between an upstream conduit and a downstream conduit of the governor body; a pilot governor that is installed in the pilot loop, opens and closes a pilot valve in response to a secondary pressure of the gas, controls the amount of the gas passing through the pilot loop, and is configured to be able to perform feedback control of the governor body so that the secondary pressure is kept constant; Equipped with a gas governor that reduces the pressure of the gas supplied from an upstream side and supplies the reduced pressure to a downstream side by changing a valve opening of the governor body using the control pressure controlled by the pilot governor, a secondary orifice disposed in the downstream conduit; an auxiliary diaphragm pressure chamber included in the pilot governor and configured to control the degree of opening or closing of the pilot valve in accordance with an internal pressure thereof; and a connecting conduit connecting the auxiliary diaphragm pressure chamber and the downstream conduit, the secondary orifice generates a negative pressure based on the flow of gas in the downstream conduit, detects a change in the flow rate of gas in the downstream conduit as a pressure change, and generates an auxiliary pressure that is lower than the secondary pressure by an amount corresponding to the negative pressure; the auxiliary diaphragm pressure chamber faces a pilot spring of the pilot governor to assist the force that opens and closes the pilot valve; the connecting pipe line includes a main line connecting the secondary orifice and the auxiliary diaphragm pressure chamber, and a sub-line that is the downstream pipe line and connects the auxiliary diaphragm pressure chamber to an upstream side or downstream side of the secondary orifice, The main line and the sub-line are each provided with a variable throttle, the internal pressure of the auxiliary diaphragm pressure chamber is a mixed pressure of the auxiliary pressure of the gas passing through the main line and the secondary pressure of the gas passing through the sub-line. Gas governor.

2. the sub-line connects the downstream pipe line upstream of the secondary orifice to the auxiliary diaphragm pressure chamber; The gas governor of claim 1 .

3. the sub-line connects the downstream pipe line and the auxiliary diaphragm pressure chamber via the main line; The gas governor of claim 1 .

4. The variable throttle is a needle valve. The gas governor according to any one of claims 1 to 3.

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