JPS58109775A - Main steam stop valve having guide with balancing hole - Google Patents
Main steam stop valve having guide with balancing holeInfo
- Publication number
- JPS58109775A JPS58109775A JP20707181A JP20707181A JPS58109775A JP S58109775 A JPS58109775 A JP S58109775A JP 20707181 A JP20707181 A JP 20707181A JP 20707181 A JP20707181 A JP 20707181A JP S58109775 A JPS58109775 A JP S58109775A
- Authority
- JP
- Japan
- Prior art keywords
- valve
- guide
- valve body
- main steam
- steam stop
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K1/00—Lift valves or globe valves, i.e. cut-off apparatus with closure members having at least a component of their opening and closing motion perpendicular to the closing faces
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Details Of Valves (AREA)
- Control Of Turbines (AREA)
- Lift Valve (AREA)
Abstract
Description
【発明の詳細な説明】
本特許は主蒸気止め弁に係わり、筒状の弁一体を保−す
るガイドを有する主蒸気止、め弁に関する。DETAILED DESCRIPTION OF THE INVENTION This patent relates to a main steam stop valve, and more particularly, to a main steam stop valve having a guide for holding a cylindrical valve integrally.
従来技術による主蒸気止め弁の断面図を第１図に示す。A sectional view of a main steam stop valve according to the prior art is shown in FIG.
弁ケーシングＩＫは上蓋２がボルトで結合されている。An upper cover 2 is connected to the valve casing IK with bolts.
この上蓋をはずすことにより、弁ケーシング内の弁体３
などを出し入れすることができる。第１図では、弁体３
は弁ケーシングにはめ込まれた弁座９に接触しており、
弁が全閉状態にあることを示している。弁を開けるとき
は弁体が８棒６によって押し上げられる。弁体の筒状部
分は上蓋から下方に突き出ている筒状のガイド１１の中
に入る。ガイドと弁体の筒状部とはわずかの間隙（Ａ部
）を有している。このｄイド１１によって、弁体の上下
運動が案出され、左右にふれることか防止されている。By removing this top cover, the valve body 3 inside the valve casing can be removed.
You can take things in and out. In Fig. 1, the valve body 3
is in contact with the valve seat 9 fitted into the valve casing,
Indicates that the valve is fully closed. When opening the valve, the valve body is pushed up by the eight rods 6. The cylindrical portion of the valve body enters a cylindrical guide 11 that projects downward from the top cover. There is a slight gap (portion A) between the guide and the cylindrical portion of the valve body. This d-id 11 allows the valve body to move up and down, and prevents it from moving left and right.
弁体と８棒は、次のよう罠組み立てられる。８棒６に８
棒ヘッド５がねじこまれている。８棒ヘッド５は、弁体
の中に入り、弁キャップ４で押えられている。弁キャッ
プは弁体にボルトで取り付けられている。弁体と８棒を
組立て構造にすることにより、侵食等で損傷をうけた場
合、その部分のみを容易に交換することができ、保守上
利点がある。８棒６は、衛帯筐（えいたいきよう）７に
よって支持されるとともにガイドされ、この衛帯筐には
、衛帯筐押え８によす、弁ケーシング１へ取りつけられ
ている。The valve body and 8 rods are assembled as follows. 8 bar 6 to 8
The rod head 5 is screwed in. The eight-rod head 5 enters the valve body and is held down by the valve cap 4. The valve cap is attached to the valve body with bolts. By assembling the valve body and the eight rods, in the event of damage due to erosion or the like, only that part can be easily replaced, which is advantageous in terms of maintenance. The eight rod 6 is supported and guided by a guard case 7, which is attached to the valve casing 1 by a guard case retainer 8.
第２図には、この８棒６を上下に、動かす駆動部を示す
。８棒にピストン１４がとりつけられてい ゛る
。このピストンはサーボケーシング１３の中にあって、
スプリング１２で下向きに押されている。FIG. 2 shows a drive unit that moves the eight rods 6 up and down. Piston 14 is attached to 8 rods. This piston is inside the servo casing 13,
It is pushed downward by a spring 12.
８棒が上に動くと、弁は開き、下に動くと閉じる。8 When the rod moves up, the valve opens, and when it moves down, it closes.
８棒を上に動かすには、ピストン１４下部に油をしる。To move the rod 8 upward, apply oil to the bottom of the piston 14.
この従来技術の問題点は、弁を閉じる時にある。The problem with this prior art is when closing the valve.
この止め弁は、緊急時に蒸気がタービンへ流入するのを
可能な限り短時間で遮断することを目的としている。し
九がって、弁の閉じる時間が短いことが重要である。弁
が、全開状態から閉じ始めると、第１図における弁体上
部チャンバー１０が、弁が下に下った分だけ容積を増す
ことになる。このとき、Ａ部即ちガイド１１と弁体３の
筒部との間隙から、チャンバー内に流入する流体が少な
いと、チャンバー内圧力が減少し、このため、弁が下に
下がろうとするのを妨げることになる。この状態を示し
た図が第３図である。（ａｌＫ示す如く、弁が全開から
全閉へ閉じていく。このとき、（ｂ）に示す如く、弁体
上部チャンバー容積は増加していく。これに伴い弁入口
、弁出口、弁体上部チャンバー内圧力は、（Ｃ）Ｋ−示
す如き挙動となる。弁入口圧力Ｐ！は蒸気供給源により
決定され、通常一定である。弁出口圧力Ｐｔ、は、主蒸
気止め弁の下流にある制御弁の挙動により左右されるが
、通常、主蒸気止め弁を閉じ始めると同時に、制御弁も
閉じるから、主蒸気止め弁を閉じ始めると同時に徐々に
トリ始めて主蒸気止め弁全閉後も梃に下っていく。一方
、弁体上部チャンバー内圧力Ｐｕは、（ｂ）に示す弁体
上部チャンバー容積の増加量と、第１図Ａ部の間隙から
流入する蒸気量との差によって、減少し、主蒸気止め弁
全閉後は、向、流入しつづける蒸気によってまた圧力を
回復し、ＰＸに一致するに至る。この経過でＰＬ〉Ｐａ
となる状態が出現する。弁口径をｌ）ｆｍ）、ＰＬ
（Ｐ、ｌとＰａ （Ｐ、）との差により、Ｆｐにかかり
。これが、スプリングによる下向きの刀ＦＢを滅するた
め、弁の閉まるスピードは落ちる。The purpose of this stop valve is to shut off the flow of steam to the turbine in the shortest possible time in the event of an emergency. Therefore, it is important that the valve closing time is short. When the valve starts to close from the fully open state, the volume of the valve body upper chamber 10 in FIG. 1 increases by the amount that the valve has moved downward. At this time, if there is little fluid flowing into the chamber from part A, that is, the gap between the guide 11 and the cylindrical part of the valve body 3, the pressure inside the chamber will decrease, and this will prevent the valve from going down. It will be a hindrance. FIG. 3 is a diagram showing this state. (As shown in alK, the valve closes from fully open to fully closed. At this time, as shown in (b), the volume of the chamber above the valve body increases. Along with this, the valve inlet, the valve outlet, and the upper chamber of the valve body increase. The internal pressure behaves as shown in (C)K-.The valve inlet pressure P! is determined by the steam supply source and is usually constant.The valve outlet pressure Pt, is the control valve downstream of the main steam stop valve. It depends on the behavior of the main steam stop valve, but normally the control valve also closes at the same time as the main steam stop valve starts to close, so it gradually starts to operate at the same time as the main steam stop valve begins to close, so that the control valve will not fall to the lever even after the main steam stop valve is fully closed. On the other hand, the internal pressure Pu of the valve body upper chamber decreases due to the difference between the amount of increase in the volume of the valve body upper chamber shown in (b) and the amount of steam flowing in from the gap in section A in FIG. After the steam stop valve is fully closed, the steam that continues to flow in will restore the pressure and reach PX.In this process, PL〉Pa
A situation will appear. The valve diameter is l) fm), PL
(P, due to the difference between l and Pa (P,), Fp is applied. This eliminates the downward sword FB caused by the spring, so the closing speed of the valve decreases.
これを防ぐためＫは、第１図Ａ部の間隙を大きくして、
弁体上部チャンバー内に流体ｔ−流れ込みやすくすれば
よいが、間隙が大きいと、ガイドの役目をはださなくな
る。また、蒸気が、凝縮圧力・温度に近い状態で使用さ
れていると、弁体の筒部、又は、弁上張などで凝着して
液化し九流体が、第１図Ａ部の間隙に入り込んで、隙間
をふさいでしまうこともおきる。この場合、弁体上部チ
ャンバー内に流入する蒸気は妨げられて、更に、Ｐａは
下ＤＵ向となり、弁を閉じる速度は落ちる。To prevent this, K increases the gap in section A in Figure 1.
It is sufficient to make it easy for the fluid to flow into the upper chamber of the valve body, but if the gap is large, it will not be able to function as a guide. In addition, if steam is used at a pressure and temperature close to condensation, it will condense and liquefy on the cylindrical part of the valve body or the valve lining, causing the fluid to enter the gap in section A in Figure 1. They can also get in and block the gaps. In this case, the steam flowing into the upper chamber of the valve body is blocked, furthermore, Pa is directed downward DU, and the speed at which the valve closes is reduced.
本発明の目的は、上記の従来技術の欠点を解消し、ガイ
ドと筒状弁体を有する主蒸気止め弁であって、閉速度を
必要速度以上に保ちうろことを可能にした主蒸気止め弁
を得ることに−ある。An object of the present invention is to solve the above-mentioned drawbacks of the prior art, and to provide a main steam stop valve having a guide and a cylindrical valve body, which allows the valve to maintain its closing speed above the required speed. It's about getting.
次に本発明の一実施例につき説明する。Next, one embodiment of the present invention will be described.
上記の従来技術の欠点を解消するＫ （１、第１図のガ
イドＩＩＫ多数の穴をあけ、あるいは、ガイド１１を網
状にする方法がある。しかし、第１図に示す如く、蒸気
は弁ケーシングの１つの入口から入るため、（第１図で
は左方よシ）この流入蒸気の一部はガイドの穴を通って
第１図におけるガイドの右方よりガイドの右方へ流れる
ことになって、両を起こす。また、穴を多数あけること
は、ガイドの強度を弱めることとなり好ましくない。K (1) There is a method of making the guide IIK shown in Fig. 1 a number of holes or making the guide 11 mesh-like. Because it enters from one entrance of the guide (toward the left in Figure 1), a portion of this incoming steam will flow through the hole in the guide from the right side of the guide in Figure 1 to the right side of the guide. In addition, it is not preferable to make many holes because it weakens the strength of the guide.
そこで本発明では、ガイドの上方からＦ方へ必要にして
十分な開口面積をもつバランスホールを配置する。Therefore, in the present invention, a balance hole having a necessary and sufficient opening area is arranged from above the guide in the F direction.
バランスホールの配置と開口面積ｔａ明する。The arrangement and opening area of the balance hole will be explained below.
弁体・８咋・ピストンなど可動部の質菫をＭ（Ｋｇｌと
する。下向きに座標ｘｆｍｌｔ−とり弁体の位置を示す
。ｘ＝Ｑのとさ、弁は全開とする。The quality of the movable parts such as the valve body, 8cm, and the piston is assumed to be M (Kgl).The position of the valve body is indicated by the coordinate xfmlt-downward.When x=Q, the valve is fully open.
Ｆｓ （Ｎｌをスプリング力とじ、Ｆｐ（Ｎ）′ｋＰ
ｕ（Ｐ、）とＰｔ（Ｐａｌの圧力差による上向きの力と
する。Ｆｓはｘ＝０、即ち弁全州のときＦ。Fs (Nl is the spring force, Fp(N)'kP
Let it be the upward force due to the pressure difference between u(P,) and Pt(Pal.Fs is F when x=0, that is, the valve is full.
（Ｎ）とし、スプリングのバネ定数ｔＫ（Ｎ／ｍ）とす
る。また、パルプがしまるときの抵抗をＦ、（Ｎ）とす
る。第１図Ａ部の間隙が、前述の如く、凝縮した流体で
ふさがれていて蒸気流体が、弁体上部チャンバーに流入
できない状態を考える。弁体上部チャンバーの容積はｘ
＝０のとき、即ちパルプ全開のときＶｏｌｍ”）とし、
ｘ ％ ０のとき、Ｖ＝Ｖｏ ＋Ａ−ｘとする。(N), and the spring constant tK (N/m) of the spring. Also, let F and (N) be the resistance when the pulp collapses. Consider a situation in which the gap in section A in FIG. 1 is blocked by condensed fluid, as described above, and steam fluid cannot flow into the upper chamber of the valve body. The volume of the upper chamber of the valve body is x
When = 0, that is, when the pulp is fully opened, Volm"),
When x % 0, V=Vo +A−x.
以上より次の式が成りたつ。From the above, the following formula holds true.
Ｍ＾十Ｆｒ Ｆｓ ＋ ＦＰ ”０ ・・・・・・
・・・（１）Ｆ、＝μｋ 但しμは抵抗係数・・・・・
・・・・（２）Ｆｍ ＝Ｆｏ Ｋ−ｘ ・
−・・−（３）１１’Ｐ ：Ｂ （Ｐｔ、 Ｐａ ）
−−＝１４）但しＢは弁の開口面積（ｍ！ ）
Ｐｔ、Ｉｄ近似的に一定と考えると
ｔ＝０ 即ち閉じ始めの加速度は、
マー０ 即ち、最大速度に到達したとき、その速度は
・・・・・・・・・（７）
この点からは、閉速度が落ちていく。したがつて、弁の
閉速度を必要速度ｖ（ｍ／Ｓ）以上に保つためには、ま
ず、与えられた条件Ｐｔ、、Ｐｔ。M^1Fr Fs + FP ”0 ・・・・・・
...(1) F, = μk, where μ is the resistance coefficient...
...(2) Fm = Fo K-x ・
-...-(3) 11'P:B (Pt, Pa)
--=14) However, B is the opening area of the valve (m!) Considering that Pt and Id are approximately constant, t = 0. In other words, the acceleration at the beginning of closing is Mar 0. In other words, when the maximum speed is reached, the speed is・・・・・・・・・(7) From this point on, the closing speed decreases. Therefore, in order to maintain the closing speed of the valve at or above the required speed v (m/S), first, the given conditions Pt, , Pt.
Ｂ、ＡＫ対し、（６）式、（方式から、’ｘ ＝ ０
テｏ連Ｆｔ灸がｙ以上となるよう、ＦｏとＫｔ−選択す
る。即ち、スプリングを適切に選ぶ。次に、’ｘ＝０と
な？）、ｘ＝ｖとなる点：ｘ７に、バランスホール會あ
け、’ｘ＝０．ｘ、−＝ｖとなった点から、弁が減速し
ないよう、弁上部チャンバーへ蒸気を流入させてＰｏ’
ｌｃ増加させる。第４図にこの挙動を示す。For B and AK, equation (6), (from the method, 'x = 0
Fo and Kt are selected so that the Ft moxibustion is greater than or equal to y. That is, choose the spring appropriately. Next, 'x=0? ), the point where x=v: a balance hole is opened at x7, 'x=0. From the point where x, -=v, steam is allowed to flow into the upper chamber of the valve so that the valve does not decelerate, and Po'
Increase lc. Figure 4 shows this behavior.
１＝＝Ｑでは、；Ｃ−０である。を−表曲線のｔ＝０で
の頑き［」θ＝マであって
’ｘ ＝ ０となるｋの最大値がＶとなるようにＦｏ。When 1==Q, ;C-0. - The rigidity of the table curve at t = 0 ['' θ = Ma so that the maximum value of k such that x = 0 is V.
Ｋｔ遇択すると、その時の弁位置はＸ −” Ｘ ｖと
なる。ガイド（第１図１１１にバランスホール全役けな
いでおくと、餐く０となり、第４図（ａｌのｍに示す如
く、弁閉速度は減速する。そこで、本発明では、このＸ
＝ＸＶの位置にバランスホールを設ける。それンこよっ
て、第４図（ａｌ、（ｂｌの（１１）に示す如く、弁は
減速することなく閉じる。If Kt is selected, the valve position at that time will be X-" , the valve closing speed decreases. Therefore, in the present invention, this X
= Provide a balance hole at position XV. Therefore, as shown in (11) in FIGS. 4(al and bl), the valve closes without deceleration.
第５図に、本発明の一実施例として弁上ぶた２にバラン
スホールを開けた例を示す。一点鎖線で示す弁全開位置
からｘｗ下った位置にバランスホールを開け、弁がｘｖ
ｔで下ったところで、蒸気が弁体上部チャンバー１０内
へ流入し、チャンバー内圧力（Ｐｕｒｔ上昇させて、弁
を下へ押し下げる。FIG. 5 shows an example in which a balance hole is made in the valve cover 2 as an embodiment of the present invention. Drill a balance hole at a position xw below the valve fully open position shown by the one-dot chain line, and
When the temperature drops at t, steam flows into the chamber 10 above the valve body, increases the chamber internal pressure (Purt), and pushes the valve downward.
スプリング力Ｆｏとスプリングのバネ定数にの選択によ
っては、マ＝００ときの士の最大値が、必要速度Ｖに達
しない場合もある。このような場合は、ｘｖの位置にバ
ランスホールｔｑけるのみでなく、弁全開点近傍にもバ
ランスホールを追加すること本、本発明の応用例である
。第６図にその例を示す。弁全開点近傍のバランスホー
ルにより流入する蒸気により、圧力ＰＵの落ち込みを小
さくし、マ＝０での速度灸をＶまで上げ、そこから更に
下に弁が動くと、Ｘ ＝ Ｘ、位置のバランスホールか
ら流入する蒸気によって士の減少を防ぎ場合によっては
更に増速することができる。Depending on the selection of the spring force Fo and the spring constant of the spring, the maximum value between when Ma=00 may not reach the required speed V. In such a case, it is an application example of the present invention to not only insert a balance hole tq at the position xv, but also add a balance hole near the valve fully open point. An example is shown in FIG. The steam flowing in through the balance hole near the valve's fully open point reduces the drop in pressure PU, increases the velocity moxibustion at Ma = 0 to V, and when the valve moves further down from there, X = X, position balance The steam flowing in from the hall can prevent the reduction of the engine speed and, in some cases, further increase the speed.
前述の如く、本発明によれば弁体の動きを保膜するガイ
ドに、適切にバランスホールヲ設ケることにより、ガイ
ドの強度を過度に弱めることなく、弁の閉速度を必要に
して十分なだけ速めることが可能な主蒸気止め弁を実現
できるという効果を奏する。As described above, according to the present invention, by appropriately providing a balance hole in the guide that prevents the movement of the valve body, the valve closing speed can be increased to meet the required speed without excessively weakening the strength of the guide. This has the effect of realizing a main steam stop valve that can be operated as quickly as possible.
第１図は従来技術を示す主蒸気止め弁の断面図、第２図
は第１図に示した主蒸気止め弁の駆動装置である油圧サ
ーボの断面図、第３図は主蒸気止め弁が閉じる際の各部
の圧力挙動を示す特性図、第４図は主蒸気止め弁が閉じ
る際の弁の挙動を示す特性図、第５図は本発明の一実施
例を示す主蒸気止め弁の部分断面図、第６図は本発明の
他の実施例を示す主蒸気止め弁の部分断面図である。Figure 1 is a sectional view of a main steam stop valve showing the prior art, Figure 2 is a sectional view of a hydraulic servo that is the drive device for the main steam stop valve shown in Figure 1, and Figure 3 is a sectional view of the main steam stop valve shown in Figure 1. A characteristic diagram showing the pressure behavior of each part when the main steam stop valve closes. Figure 4 is a characteristic diagram showing the behavior of the main steam stop valve when it closes. Figure 5 is a part of the main steam stop valve showing an embodiment of the present invention. 6 is a partial sectional view of a main steam stop valve showing another embodiment of the present invention.
Claims (1)
部の外形よシわずかに大きな内径を有する筒状のガイド
を有する主蒸気止め弁において、前記弁体の全開位置か
ら下方位置の前記ガイド部分にバランスホールを配設し
たことを特徴とするバランスホール付きガイドを有する
主蒸気止め弁。1. In a main steam stop valve having a cylindrical valve body and a cylindrical guide that protects the opening and closing operations of the valve body and has an inner diameter slightly larger than the outer diameter of the cylindrical portion of the valve body, when the valve body is fully opened. A main steam stop valve having a guide with a balance hole, characterized in that a balance hole is provided in the guide portion at a position below the position.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20707181A JPS58109775A (en) | 1981-12-23 | 1981-12-23 | Main steam stop valve having guide with balancing hole |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20707181A JPS58109775A (en) | 1981-12-23 | 1981-12-23 | Main steam stop valve having guide with balancing hole |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS58109775A true JPS58109775A (en) | 1983-06-30 |
| JPH0245070B2 JPH0245070B2 (en) | 1990-10-08 |
Family
ID=16533713
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP20707181A Granted JPS58109775A (en) | 1981-12-23 | 1981-12-23 | Main steam stop valve having guide with balancing hole |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS58109775A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5300723A (en) * | 1990-12-28 | 1994-04-05 | Yamaha Corporation | Electronic musical instrument |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1956987A (en) * | 1931-01-28 | 1934-05-01 | Atwood & Morrill Co Inc | Trip valve |
| US3580288A (en) * | 1968-10-18 | 1971-05-25 | Fisher Governor Co | Flow control device including a pressure-balanced single-seated valve plug |
-
1981
- 1981-12-23 JP JP20707181A patent/JPS58109775A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1956987A (en) * | 1931-01-28 | 1934-05-01 | Atwood & Morrill Co Inc | Trip valve |
| US3580288A (en) * | 1968-10-18 | 1971-05-25 | Fisher Governor Co | Flow control device including a pressure-balanced single-seated valve plug |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5300723A (en) * | 1990-12-28 | 1994-04-05 | Yamaha Corporation | Electronic musical instrument |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0245070B2 (en) | 1990-10-08 |
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