JPS61197772A - Mud pump piston - Google Patents
Mud pump pistonInfo
- Publication number
- JPS61197772A JPS61197772A JP60037453A JP3745385A JPS61197772A JP S61197772 A JPS61197772 A JP S61197772A JP 60037453 A JP60037453 A JP 60037453A JP 3745385 A JP3745385 A JP 3745385A JP S61197772 A JPS61197772 A JP S61197772A
- Authority
- JP
- Japan
- Prior art keywords
- piston
- hub
- rubber
- flange
- cylindrical
- 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.)
- Pending
Links
Landscapes
- Details Of Reciprocating Pumps (AREA)
- Reciprocating Pumps (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は、ピストンロッドに固定された金属製ハブとこ
れに嵌合装着されたピストンラバーとよシ成るマッドポ
ンプのピストンに関する。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a piston for a mud pump, which comprises a metal hub fixed to a piston rod and a piston rubber fitted to the hub.
従来技術
゛石油の油井等の掘削に際して、ロックビットの、冷却
潤滑及び掘り屑の回収等の目的で地上又は海上と掘削部
との間にマッドを循環させるため、地上又は海上のリグ
に設置されるマッドポンプは、Ｄ４ ぼりｎ ／Ｉ Ｖ
ｅｘ ／、−Ｊ Ｊ ハ宜ｌハ畦用震嘲ち皿す（ｈ
スので、単動又は複動のピストンポンプが使用される
。又、送シ出す流体がピストンとライナーを摩耗させや
すい砂分等が混入したマッドである関係上、ライナーが
摩耗した場合にも常にピストンがライナーに圧接し、高
い流体圧力を確実にシールして摺動することができるこ
とが必要である。。Conventional technology: When drilling oil wells, rock bits are installed on land or sea rigs in order to circulate mud between the ground or sea and the drilling part for the purpose of cooling, lubricating, and collecting drilling debris. The mud pump is D4 Borin/I V
ex /, -J J
Therefore, single-acting or double-acting piston pumps are used. In addition, since the fluid being pumped out is mud mixed with sand and other substances that tend to wear out the piston and liner, even if the liner is worn out, the piston is always in pressure contact with the liner, ensuring a reliable seal against high fluid pressure. It is necessary to be able to slide. .
そのため、マッドポンプのピストンは、第５図に示ス如
く、ピストンロッド１に固定され、円筒部２とフランジ
部３とよ構成る金属製ハブ４と、ハブ４０円筒部２に嵌
合され一方の端面５を上記フランジ部３の一方の□面に
面接触させ、他方の端面６をバックアッププレート７で
押えて装着した ゛ピストンラバー８とで構成し、これ
を第６図に示 □す如く、ハブ４のフランジ部３０局面
とピストンラバーの局面の一部分とライナ９．０内周面
との間に適当な間隙を残して、ピストンラバー８のバッ
クアッププレート側端面のリップ部１０からある範囲の
外周面をラバー自身の弾力によりライナ９の内面に圧接
させてライナ９内に装着されている。Therefore, as shown in FIG. 5, the piston of the mud pump is fixed to a piston rod 1, and has a metal hub 4 composed of a cylindrical portion 2 and a flange portion 3, and a hub 40 fitted into the cylindrical portion 2. The end face 5 of the flange portion 3 is brought into surface contact with one □ face of the flange portion 3, and the other end face 6 is held down by a backup plate 7. , a certain range from the lip portion 10 of the back-up plate side end surface of the piston rubber 8, leaving an appropriate gap between the surface of the flange portion 30 of the hub 4, a portion of the surface of the piston rubber, and the inner peripheral surface of the liner 9.0. The outer circumferential surface of the rubber is pressed into contact with the inner surface of the liner 9 by the elasticity of the rubber itself, and is installed in the liner 9.
この構成によシ、ポンプの吐出圧力が上昇すればする程
、リップ部１０は強くライナ９の内面に圧接し、又、経
時的にライナ９及びピストンラバー８のリップ部１０が
摩耗した場゛合にも常にリップ部１０がライナ９の内面
に圧接し、確実にシール状態を維持して摺動できるよう
になっている。With this configuration, as the discharge pressure of the pump increases, the lip portion 10 comes into stronger pressure contact with the inner surface of the liner 9, and if the lip portion 10 of the liner 9 and the piston rubber 8 wears out over time. In any case, the lip portion 10 is always in pressure contact with the inner surface of the liner 9, so that the sealing state can be maintained reliably and the lip portion 10 can be slid.
□ 又、ハブ４の円筒部２の外周円筒面とフランジ部
３のピストンラバー８の接触面とは適当な湾曲面１１を
介して接続し、応力集中を回避するようにし、ピストン
ラバー８のこれに対応する部分も丸みをつけて互いに密
着するようにしている。□ Also, the outer cylindrical surface of the cylindrical portion 2 of the hub 4 and the contact surface of the piston rubber 8 of the flange portion 3 are connected via a suitable curved surface 11 to avoid stress concentration, and the contact surface of the piston rubber 8 is The corresponding parts are also rounded so that they are in close contact with each other.
ところで、上記構成のピストンをマッドポンプに装着し
て使用を重ねると、経時的に、ピストンラバー８のハブ
フランジ３０面に接する側の端部、付近局面が第７図中
にハツチングで示す如く摩耗するとともに、マッドがピ
ストンロッド１の外周面とピストンラバー内局面との間
を経由して流出する現象が見られ、その結果、ピストン
ラバーの寿命が短かくなる。By the way, when a piston with the above configuration is installed in a mud pump and used repeatedly, over time, the end of the piston rubber 8 in contact with the hub flange 30 surface and the surrounding surface wear out as shown by hatching in FIG. At the same time, a phenomenon is observed in which mud flows out through the space between the outer circumferential surface of the piston rod 1 and the inner surface of the piston rubber, and as a result, the life of the piston rubber is shortened.
その原因を考察するに、第８図に示す如くポンプ作動時
、ピストンラバー８がマッドにょシ加圧されると、ピス
トンラバー８は直径方向に内側と外側との両側に膨らも
うとする。しかるに、ピストンラバー８の内周面はハブ
４０円筒部２に圧接しているので、内方に膨出すること
はできず、その分、外方に膨出する。リップ部ＩＯはも
ともとライナ・、−９の内面に圧接しているのでこの付
近は外方に・膨出しにくい。又、ピストンラバー８のフ
ランジ３側は布地プライラバーとして、補強されている
が、図において右端側から強い押圧力で加圧された場合
は、湾曲面１１に沿って、円筒面側からフランジ面側に
滑る。これらの結果、ピストンラバー８は、フランジ３
に接する側端部付近の外周部、が外側にせり出し、ライ
ナ９の内面に押圧され、ピストンの往復運動により摩耗
が起、きピストンの破損につながる。又、同時に永久歪
みを生じ、押圧力が除去され半径方向外方及び内、方へ
の膨出力がなくなると、摩耗した部分がライナー９の内
面から離れるとともに、ピストンロッド１の外面とピス
トンラバー８の間の密着性が低下し、そこを通ってリッ
プ部をバイパスしてマット°が流出ｌ−、ハブ及びピス
トンラバーの摩耗を起すものと考えられる。To consider the reason for this, as shown in FIG. 8, when the piston rubber 8 is pressurized by mud during pump operation, the piston rubber 8 tends to expand inward and outward in the diametrical direction. However, since the inner circumferential surface of the piston rubber 8 is in pressure contact with the cylindrical portion 2 of the hub 40, it cannot bulge inward, but bulges outward accordingly. Since the lip portion IO is originally in pressure contact with the inner surface of the liner -9, it is difficult for this area to bulge outward. In addition, the flange 3 side of the piston rubber 8 is reinforced with cloth ply rubber, but if a strong pressure is applied from the right end side in the figure, the flange surface will move along the curved surface 11 from the cylindrical surface side. Slide to the side. As a result, the piston rubber 8 is attached to the flange 3
The outer periphery near the side end in contact with the liner 9 protrudes outward and is pressed against the inner surface of the liner 9, causing wear due to the reciprocating movement of the piston, leading to breakage of the piston. At the same time, permanent deformation occurs, and when the pressing force is removed and the radially outward and inward expansion force disappears, the worn part separates from the inner surface of the liner 9 and the outer surface of the piston rod 1 and the piston rubber 8. It is thought that the adhesion between the piston and the piston is reduced, and the matte flows out through the lip, bypassing the lip, causing wear on the hub and piston rubber.
発明の目的
本発明は、従来のマッドポンプピストンの上述の問題点
にかんがみ、経時的にピテトンラ・“−の。OBJECTS OF THE INVENTION In view of the above-mentioned problems of conventional mud pump pistons, the present invention has been made to solve the problems of conventional mud pump pistons.
外周面の摩耗が少なく、寿命の長いピストンを提供する
午とを目的とする。The purpose is to provide a piston with less wear on the outer circumferential surface and a long life.
不発、明は上記の目的を達成させるために、マッドポン
プピストンのハブの円筒部の円筒面と、フランジ部のピ
ストンラバー接、触面との交叉部ニ、これらの互いに直
交する円筒面と平面よりピストンラバー側に山々いよう
に上記両面を接続する移行湾曲部を設けたことを特徴と
する。In order to achieve the above-mentioned purpose, the cylindrical surface of the cylindrical part of the hub of the mud pump piston, the piston rubber contact of the flange part, the intersection part with the contact surface, and these cylindrical surfaces and planes that are perpendicular to each other. The present invention is characterized in that a transition curved portion connecting the two surfaces is provided so as to be closer to the piston rubber side.
、作用、
マッドポンプのピストンをこのように構成したことによ
シ、ポンプ作動によシピストンラバーが軸方向、に加圧
され、半径方向内方と外方に膨出しようとする力が発生
すると、ハブ円筒面よシ内、方に凹入して湾曲面が設け
られているので、ビストンラバーは半径方向内方にも膨
出し、その分だけ、外方に膨出する量が減少する。しか
も、ハブの円筒面とフランジ面とを接続する湾曲面が、
これら両面に接する円弧状断面の曲面でなく、互いに直
交する両面のラバー側と逆の側に設けられているコトニ
よシ、ピストンラバーのこの部分に対応する隅角部を、
ハブの曲面に沿った形状とする必要がなく、作動時、マ
ッドによシ加圧された場合、ピストンラバーのこの隅角
部は／Ｓプの湾曲した凹入部に食い込むことと相俟って
、ラバーが／Ｓブの円筒面からフランジ面に沿って移動
するように変形することが防止される。By configuring the piston of the mud pump in this way, the pump operation pressurizes the piston rubber in the axial direction, generating a force that tends to bulge radially inward and outward. Then, since the hub cylindrical surface is recessed inward and has a curved surface, the piston rubber also bulges inward in the radial direction, reducing the amount of bulging outward by that amount. . Moreover, the curved surface connecting the cylindrical surface and flange surface of the hub is
Rather than the curved surface of the circular arc cross section touching both sides, the corner part corresponding to this part of the piston rubber is provided on the side opposite to the rubber side of both sides that are orthogonal to each other.
There is no need for the shape to follow the curved surface of the hub, and when pressurized by the mud during operation, this corner of the piston rubber will bite into the curved recess of the /SP. , the rubber is prevented from being deformed so as to move from the cylindrical surface of the /S tube along the flange surface.
以上の結果、ピストンラバーの半径方向外方へのせシ出
しが、従来に比較して減少し、ライナとの摩擦による摩
耗が減少するとともに、永久変形によるハブの円筒面と
の間の密着性の低下も減少し、シール効果が維持される
。As a result of the above, the radial outward protrusion of the piston rubber is reduced compared to conventional products, the wear due to friction with the liner is reduced, and the adhesion between the piston rubber and the cylindrical surface of the hub due to permanent deformation is reduced. The drop is also reduced and the sealing effect is maintained.
実施例
第１図は、本発明を単動式マッドポンプのピストンに適
用した実施例を示す図であって、第５図で説明した従来
のピストンと同一の部材に対しては同一の符号を付して
説明する。Embodiment FIG. 1 is a diagram showing an embodiment in which the present invention is applied to a piston of a single-acting mud pump. The same members as those of the conventional piston explained in FIG. 5 are designated by the same reference numerals. This will be explained below.
この実施例では、ピストンのハブ４の円筒状部２の外周
面の円筒面と、フランジ部３のピストンラバー８の接触
する面とは、これらの互いに直交する円筒面と平面よシ
ピストンラバー８側に出ないような曲線断面の移行湾曲
部１１／で接続されている。In this embodiment, the cylindrical surface of the outer circumferential surface of the cylindrical portion 2 of the piston hub 4 and the contact surface of the piston rubber 8 of the flange portion 3 are arranged so that the cylindrical surface and the plane that are perpendicular to each other are in contact with the piston rubber 8. They are connected by a transition curved portion 11/ with a curved cross section that does not protrude to the side.
又、ピストンラバー８のこの部分に対応する隅角部には
従来の如く丸みがつけられていない。Further, the corner portion of the piston rubber 8 corresponding to this portion is not rounded as in the conventional case.
その他の構成は前述の従来の装置と同様である。The rest of the configuration is similar to the conventional device described above.
上記の構成によシ、ポンプ作動時、ピストンラバー８が
加圧されても、ピストンラバー８のハブフランジ３に接
する部分近傍の外周面が半径方向外周に膨出する量が減
少し、摩耗が従来に比して減少する。With the above configuration, even if the piston rubber 8 is pressurized during pump operation, the amount by which the outer peripheral surface of the piston rubber 8 in the vicinity of the portion in contact with the hub flange 3 bulges outward in the radial direction is reduced, thereby reducing wear. Reduced compared to before.
第２図に示す如く、ハブ４のフランジ３のピストンラバ
ーに接する面に同心的に数条の環状突起１２を設けたシ
、第３図に示す如く、円錐状の突起工３ｔ−設けたなら
ば、作動時ピストンラバー８にこれらの突起１２．１３
が食い込み、その結果、ラバー８が半径方向外方にフラ
ンジ面とずれてせシ出すことがなお一層確実に防止され
る。フランジに設ける凹凸を第４図に示す如く、ゴルフ
ボールのディンプル状の凹み１４としても同様の効果が
得られる。As shown in Fig. 2, several annular protrusions 12 are provided concentrically on the surface of the flange 3 of the hub 4 in contact with the piston rubber, and as shown in Fig. 3, a conical protrusion 3t is provided. For example, these protrusions 12 and 13 are formed on the piston rubber 8 during operation.
As a result, the rubber 8 is even more reliably prevented from sliding outward in the radial direction from the flange surface. A similar effect can be obtained by using dimple-shaped depressions 14 on a golf ball as the unevenness provided on the flange, as shown in FIG.
効果
以上の如く、本発明によれば、簡単な構成で、マッドポ
ンプ作動時にピストンラバーが半径方向外方にせシ出す
量を減らすことができ、その結果ライナーとの摩擦によ
る摩耗が減少し、ピストンラバーの寿命の向上に顕著な
効果が得られる。Effects As described above, according to the present invention, with a simple configuration, it is possible to reduce the amount that the piston rubber protrudes outward in the radial direction when the mud pump is operated, and as a result, wear due to friction with the liner is reduced, and the piston A remarkable effect can be obtained in improving the life of the rubber.
実施例としてピストンハブのフランジの一方にピストン
ラバーを設けた単動式ピストンポンプのピストンの例を
説明したが、フランジの両側に円筒部を有するハブに夫
々ピストンラバーを嵌装した複動式ピストンポンプのピ
ストンに対しても本発明を適用することができ、同様の
効果を得ることができる。As an example, we have explained an example of a piston of a single-acting piston pump in which a piston rubber is provided on one side of the flange of a piston hub, but a double-acting piston in which a piston rubber is fitted into a hub having cylindrical portions on both sides of the flange has been described. The present invention can also be applied to the piston of a pump, and similar effects can be obtained.
第１図は本発明の実施例の構成を示す縦断面図、第２図
は本発明の他の実施例のピストンハブを中心線で切って
示す斜視図、第３図及び第４図はさらに他の実施例のピ
ストンハブの同様の斜視図九第５図は従来のピストンの
構成の１例を示す縦断面図１．第６図はそのピストンを
ライナに装着した状態を示す縦断面図、第７図はそのピ
ストンラバーの経時変化状態を示す断面図、第８図はそ
の変化の原因を説明するための図式図である。
１・・・ピストンロッド ２・・・ハブの円筒部３・
・・ハブのフランジ部 ４・・・ハブ５・・・フランジ
のラバー接触面
８・・・ピストンラバー ９・・・ライナ１０・・・
リップ部 １１’・・・湾曲面１２、１３．１
４・・・凹凸部
第１図
第２図
第３図
第４図FIG. 1 is a longitudinal sectional view showing the configuration of an embodiment of the present invention, FIG. 2 is a perspective view showing a piston hub of another embodiment of the present invention cut along the center line, and FIGS. FIG. 5 is a similar perspective view of a piston hub according to another embodiment. FIG. Fig. 6 is a longitudinal cross-sectional view showing the state in which the piston is attached to the liner, Fig. 7 is a cross-sectional view showing how the piston rubber changes over time, and Fig. 8 is a schematic diagram for explaining the cause of the change. be. 1... Piston rod 2... Cylindrical part of the hub 3.
... Flange part of hub 4 ... Hub 5 ... Rubber contact surface of flange 8 ... Piston rubber 9 ... Liner 10 ...
Lip portion 11'...Curved surface 12, 13.1
4...Irregularities Fig. 1 Fig. 2 Fig. 3 Fig. 4
Claims (2)
より成る金属製ハブと、該ハブの円筒部に嵌合され一方
の端面を上記フランジの一面に面接触させて装着され、
他方の端面のリップがライナの内面に圧接摺動する環状
ピストンラバーとを有するマッドポンプのピストンにお
いて、上記のハブの円筒部の円筒面とフランジ部のピス
トンラバー接触面との交叉部に、これらの互いに直交す
る円筒面と平面よりピストンラバー側に出ないようにこ
れら両面を接続する移行湾曲部を設けたことを特徴とす
るピストン。(1) a metal hub fixed to a piston rod and consisting of a cylindrical part and a flange part; fitted into the cylindrical part of the hub and mounted with one end surface in surface contact with one surface of the flange;
In a mud pump piston having an annular piston rubber whose other end lip slides in pressure contact with the inner surface of the liner, these are placed at the intersection of the cylindrical surface of the cylindrical portion of the hub and the piston rubber contact surface of the flange portion. A piston characterized in that a cylindrical surface perpendicular to each other and a transition curved portion connecting these surfaces so as not to protrude toward the piston rubber side from the plane are provided.
より成る金属製ハブと、該ハブの円筒部に嵌合され一方
の端面を上記フランジの一面に面接触させて装着され、
他方の端面のリップがライナの内面に圧接摺動する環状
ピストンラバーとを有するマッドポンプのピストンにお
いて、上記のハブの円筒部の円筒面とフランジ部のピス
トンラバー接触面との交叉部に、これらの互いに直交す
る円筒面と平面とよりピストンラバー側に出ないように
両面を接続する移行湾曲面部を設けるとともに、上記フ
ランジのピストンラバー接触面に凹凸を設けたことを特
徴とするピストン。(2) a metal hub fixed to the piston rod and consisting of a cylindrical part and a flange part; fitted into the cylindrical part of the hub and mounted with one end surface in surface contact with one surface of the flange;
In a mud pump piston having an annular piston rubber whose other end lip slides in pressure contact with the inner surface of the liner, these are placed at the intersection of the cylindrical surface of the cylindrical portion of the hub and the piston rubber contact surface of the flange portion. A piston characterized in that a transition curved surface portion is provided which connects the mutually perpendicular cylindrical surface and the flat surface so as not to protrude toward the piston rubber side, and an unevenness is provided on the piston rubber contact surface of the flange.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60037453A JPS61197772A (en) | 1985-02-28 | 1985-02-28 | Mud pump piston |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60037453A JPS61197772A (en) | 1985-02-28 | 1985-02-28 | Mud pump piston |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS61197772A true JPS61197772A (en) | 1986-09-02 |
Family
ID=12497924
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60037453A Pending JPS61197772A (en) | 1985-02-28 | 1985-02-28 | Mud pump piston |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61197772A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2013527899A (en) * | 2010-04-07 | 2013-07-04 | ロベルト・ボッシュ・ゲゼルシャフト・ミト・ベシュレンクテル・ハフツング | Annular seal member |
| CN103671080A (en) * | 2013-12-10 | 2014-03-26 | 中联重科股份有限公司 | Piston mechanism and concrete pumping machine comprising same |
| WO2021128037A1 (en) * | 2019-12-23 | 2021-07-01 | 江苏盐邦泵业制造有限公司 | Wear-resistant plunger slurry pump |
| CN113757076A (en) * | 2021-11-09 | 2021-12-07 | 杭州赛奇机械股份有限公司 | Wear-resisting air compressor piston that new energy automobile used |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5527599A (en) * | 1978-08-16 | 1980-02-27 | Lucas Industries Ltd | Piston and cylinder type pump assembly |
| JPS58131469A (en) * | 1982-01-29 | 1983-08-05 | Honda Motor Co Ltd | Seal device |
-
1985
- 1985-02-28 JP JP60037453A patent/JPS61197772A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5527599A (en) * | 1978-08-16 | 1980-02-27 | Lucas Industries Ltd | Piston and cylinder type pump assembly |
| JPS58131469A (en) * | 1982-01-29 | 1983-08-05 | Honda Motor Co Ltd | Seal device |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2013527899A (en) * | 2010-04-07 | 2013-07-04 | ロベルト・ボッシュ・ゲゼルシャフト・ミト・ベシュレンクテル・ハフツング | Annular seal member |
| CN103671080A (en) * | 2013-12-10 | 2014-03-26 | 中联重科股份有限公司 | Piston mechanism and concrete pumping machine comprising same |
| WO2021128037A1 (en) * | 2019-12-23 | 2021-07-01 | 江苏盐邦泵业制造有限公司 | Wear-resistant plunger slurry pump |
| CN113757076A (en) * | 2021-11-09 | 2021-12-07 | 杭州赛奇机械股份有限公司 | Wear-resisting air compressor piston that new energy automobile used |
| CN113757076B (en) * | 2021-11-09 | 2022-02-25 | 杭州赛奇机械股份有限公司 | Wear-resisting air compressor piston that new energy automobile used |
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