WO1983001822A1

WO1983001822A1 - Valve of the type comprising a rotatable valve member, such as ball valves or cocks

Info

Publication number: WO1983001822A1
Application number: PCT/DK1982/000102
Authority: WO
Inventors: Knud Anker Kristensen
Original assignee: Knud Anker Kristensen
Priority date: 1981-11-16
Filing date: 1982-11-15
Publication date: 1983-05-26
Also published as: SE439971B; NO158356C; DK147516C; IT8224263A0; NO832537L; FR2516627B1; SE8303953D0; NO158356B; SE8303953L; BE895014A; DK505081A; FR2516627A1; EP0098268A1; GB2123120B; FI832529L; FI832529A0; DE3249206T1; FI74335C; GB2123120A; FI74335B

Abstract

By means of a valve of the type comprising a rotatable valve member, such as ball valves or cocks, and of the type which comprises a valve casing provided with at least two valve ports and an opening provided with a turnable valve shaft which serves to turn a valve element (1) which is carried rotatably and being rotatable around a rotation axis (7) estabilishing at least one closing and one open position of the valve for which purpose the valve element (1) comprises at least one equatorial area (10) having at least one bore (2) and being successively led past a sealing ring positioned at one of the connectable openings of the valve casing when turning the valve element (1) around its rotation axis (7), and in which the valve element (1) at the closed position of the valve is lying tight against the sealing ring along a ring shaped contact area positioned farther away from the rotation axis (7) or the centre (8) of the valve element (1) than is the case for the surface (3) of the valve element (1) at other places of the equatorial area (10), a valve is obtained having a long lifetime in which a sealing is provided at extremely high pressures without implying mentionable friction against the valve being turned away from its open position.

Description

Valve of the Type Comprising a Rotatable Valve Member, Such as Ball Valves or Cocks.

The present invention concerns a valve of the type comprising a rotatable valve member, such as ball valves or cocks, and of the type which compris¬ es a valve casing provided with at least two for external connections defined openings and an opening provided with a turnable shaft which serves to turn a valve element which is carried rotatably and being rotatable around a ro¬ tation axis establishing at least one closing and one open position of the valve forwhich purpose the valve element comprises at least one equatorial area having at least one bore and being successively led past a sealing ring positioned at one of the connectable openings of the valve casing when turn- ing the valve element around its rotation axis.

The valve according to the present invention is characterized in that the valve element at the clos¬ ed position of the valve is lying tight against the sealing ring along a ring shaped contact area position- ed longer away from the rotation axis of the valve ele¬ ment than is the case for the surface of the valve element at other places^'of the equatorial area or zone.

In this way a valve of the aforementioned art is obtained whereby at the open position of the valve no friction or a comparatively small friction is pre¬ sent counteracting upon turning of the valve element in the closing direction, this is because the contact¬ ing of the valve element with the gasket ring estab¬ lishing the sealing takes place with a lower contact- ing pressure than the contacting pressure occurring by the closed position of the valve. Thus, a valve with a longer lifespan before an exchange of the gasket ring to be made is presented, and this is realized as well due to the lower pressure against the sealing ring at the open position of the valve as due to the fact that the edges of the bore of the valve element pass in front of the sealing rings under a much lower contacting pressure against these rings than the contacting pressure being exerted by the valve element at the closed position of the valve. The contacting pressure against the sealing rings at the closed condition of the valve may due to the construc- tional features of the valve be much higher than the contacting pressure within valves belonging to the state of the art in which the contacting pressure has such a size that to the carrying out of the closing of the valve a turning force of maximum 75 N m has to be exerted, whereas in case of the present valve a sealing contacting pressure is obtainable whereto a turning force of the size of 350 N has to be exerted upon the turnable shaft of the valve, i.e. corresponding to a sealing pressure which is about five times larger than until now obtained by means of the known ball valves or cocks.

Each equatorial zone section incorporating the mentioned larger distance from the centre of the valve element or from the rotation axis is appropriately manufactured wider than the largest diameter of the contacting face of the sealing ring with the valve element. In this way it is ensured that the total contacting surface of the sealing ring obtains equal sealing pressure or contacting pressure against the valve element at the closed condition of the valve.

In case the valve is of the cock type having a cylindrically or conically shaped valve element the equatorial area f the valve element, i.e. the aforemen- tioned area, which at the turning operation of the valve passes the contacting area of the sealing ring, is suit- ably composed of inpairs of oppositely arranged cylin¬ drical or conical surface sections having the same sha¬ pe whereby simultaneously at least one pair of these said oppositely arranged cylindrical or conical surface - sections have one common axis and incorporate a lar¬ ger distance to the rotation axis of the valve element than the case is for the remaining pairs of the afore¬ mentioned cylindrical or conical surface sections. This concerns a precise description of a preferred embodiment of valves of the cock type according to the present in¬ vention.

In case the valve is a ball valve appropriately the equatorial area of the valve element is composed of in pairs oppositely arranged ball surface sections having the same curvature of the surface, whereby simultaneous¬ ly at least one pair of the said oppositely arranged ball surface sections possess the same centre and pos¬ sess a larger distance to the centre of the ball than it is the case for the remaining pairs of ball surface sections. Thereby a pre¬ ferred embodiment for a modified ball valve is defined since only a part of the equatorial zone of the valve element needs to have its centre at the rota¬ tion axis of the valve. The pair of ball shaped, conical or cylindrical surface sections comprising no bores suitably exhibit on the valve element the largest distance to the centre of the ball or to the axis of the valve element, where¬ by simultaneously each surface section having a bore exhibits a shorter' distance to the centre of the ball or to the axis of the valve element. Thereby is ensured that the highest contacting pressure of the valve element against the sealing rings within the valve casing occur between the sealing rings and the pair of surface sections on the valve element presenting no bores .

The sealing ring at each of the connectable open-

(A, ^'_h^~ι-i ings of the valve casing in front of the equatorial zone of the valve element is suitably fastened to the valve casing,. and simultaneously the valve ele¬ ment at the part of the equatorial zone having bores re- mains out of contact with the sealing ring. In this way an embodiment is construed whereby the orifices of the bores of the valve element never get into contact with the sealing ring which augments the lifetime of. it because wear caused by the mentioned orifices is eliminated.

Embodiments according to the present invention are explained in more detail in the following with re¬ ference to the accompanying drawings on which

Fig. 1 illustrates a valve element construed ac- cording to the present invention.

Fig. 2 illustrates a side view of the element shown in fig. 1 , Fig. 3 illustrates a front view of the element shown in fig. 1 , Fig. 4 shows a modified embodiment but viewed in cross section along I-I in fig. 3, Fig. 5 shows a cross section along II-II in fig. 3, Fig. 6 illustrates an embodiment having plane sur¬ faces at the bore, and Fig. 7 illustrates a sealing ring.

In fig. 1 of the accompanying drawings a valve ele¬ ment 1 according to the present invention and of the ball type is illustrated. The valve element has a bore 2 with an orifice lying at a ball surface section 3 having a shorterdistance io .the centre of the ball than a ball surface section 4 having no bore orifices. Uppermost the valve element comprises a surface 5 in the middle of which a box shaped projection is present de¬ fined to engage a turnable valve shaft (not shown) paε- sing through the valve casing (not shown) whereby the turnable valve shaft at the coupling end unto the valve element possesses a notch being complementary to the projection 6.

In fig. 2 of the accompanying drawings the same valve element is shown viewed from the side and having rounded shaped transition faces between the surface parts 3 and 4. This valve is of the one-way valve type having one single bore in the valve element; but accord¬ ing to the present invention the valve might be of the two-way and three-way valve types comprising valves of the cock type as well as of the ball type. The valve element 1 is turnable around a rotation axis 7, and the ball surface 4 has its centre common with the cen¬ tre 8 of the valve element. In the present case the centre of the ball is situated at the intersection point between the rotation axis 7 and the axis 9 of the bore 2. In fig. 2 the equatorial zone or area 10 of the valve element is shown, namely the .zone or area, which at the turning of the valve element 1 successively is led past a sealing ring in the valve casing. An embodi- ment of a sealing ring 12 is shown in fig. 7 whereby the contacting area 14 of the sealing ring serving for the tightening against the valve element when occupying closed position is shown having an oblique position in relation to the plane of the sealing ring. An internal projection 16 manufactured on the sealing ring has in prac¬ tice shown itself to be able to remove noise of the valve in its open position at those embodi¬ ments of the valve element in which the surface 3 also is brought into contact with the gasket ring 12 even through the contacting pressure is lower.

The valve element 1 is illustrated in front view in fig. 3 of the accompanying drawings. Also here the equatorial zone or area 10 is shown.

A cross sectional view along I-I of fig. 3 is shown in fig. 4 of the accompanying drawings, namely in an embodiment in which the projection6 is substituted by a notch 18 arranged to engage the turnable. valve shaft. By a dotted line the usual cross sectional contour 20 for a usual ball valve is shown, hereby it is made easier understandable why the valve element 1 accord- ing to the present invention forms a lower contacting pressure with the sealing rings 12 of the valve casing whenever the open valve condition is present contrary to the case in which the valve is in closed condition. A cross sectional view through the valve element 1 within the equatorial area 10 along II-II in fig. 3 is shown in fig. 5 of the accompanying drawings. By means of a dot-and-dash line 22 the orbit of the valve element 1 for the ball surface section 4 is indicated. An embodiment for the valve element 1 is shown in fig. 6 of the accompanying drawings and whereby only the opposite surface sections 4 are ball shaped exhibiting rounded shaped transitions to plane shaped surfa¬ ces 26 in which the bore 2 of the valve element opens out and whereby a surface 24, opposite to the surface 5, also has a plane shape. The distance between the sur¬ faces 5 and 24 corresponds to the width of the equato¬ rial area 10. In this way a valve casing with low con¬ struction height can be obtained and in which case also all advantages according to the present invention are employed.

The rounded shaped transitions to the surfaces 26 cause less wear upon the sealing ring 12 than the bore orifices in"a ball shaped valve element. Whenever more than one bore is present in the valve element 1 , at least one surface section without bores should be present in the equatorial area of said valve element 1 , said surface section having a larger width measured along the periphery of the valve element l by the equatorial area 10 than the largest diameter of the sealing ring 12 for its contact area 14 with the val-

c:-:?ι ve element 1. I.e., the contact area 14 is smaller than the surface section without bores. The connectable open¬ ings of the valve casing which openings might be dosed by the surface sections being without bores on the valve element 1 are all situated, radially facing the equatori¬ al zone or area 10; but the valve casing may comprise other connectable openings, one of which e.g. could be arranged opposite the opening in the valve casing for the valve shaft.

Claims

C l a i m s :

1. Valve of the type comprising a rotatable valve member, such as ball valves or cocks, and of the type which comprises a valve casing provided with at least two valve ports and an opening .provided with a turnable valve shaft which ser¬ ves to turn a valve element which is carried rotatably

- and being rotatable around a rota¬ tion axis establishing at least one closing and one open position of the valve for which purpose the valve element comprises at least one equatorial area having at least one bore and being successively led past a sealing ring positioned at one of the connectable ope¬ nings of the valve casing when turning the valve ele¬ ment around its rotation axis, c h a r a c t e r i z - e d in that the valve element (1) at the closed^' posi¬ tion of the valve is lying tight against the sealing ring (12) along a ring shaped contact area positioned farther away from the rotation axis 7) or the centre (8) of the valve element (1) than is -the case for the surface (3,26) of the valve element (1) at other places of the equa¬ torial area or zone (10). ,₍

2. Valve according to claim 1, c h a r c t e r - i z e d in that each contact area ^4) ar part o : he equatori¬ al area incorporating the mentioned larger distance from the centre (8) or rotation axis (7) of the valve element ( 1 ) is wider (30) than the largest diameter _t of " the contacting face (14) of the sealing ring (12) with the valve element (1 ) .

3. Valve according to claim 1 or 2 in that case the valve is of the cock type having a cylindrically or conically shaped valve element, c h a r a c t e r ¬ i z e d in that the equatorial area (10) of the valve element, i.e. the area, hich at the turning operation of the valve passes the contacting area of the sealing ring (12), is composed of in pairs of oppositely arranged cylindrical or conical surface sections having the same shape whereby simultaneously at least one pair of the¬ se said oppositely arranged cylindrical or conical surface sections have one common axis (7) and incor- porate a larger distance to the rotation axis (7) of the valve element (1) than the case is for the remain¬ ing pairs of the aforementioned cylindrical or conical surface sections.

4. Valve according to claim 1 or 2 in case the valve is a ball valve, c h a r a c t e r i z e d in that the equatorial area (10) of the valve element (1) is composed of in pairs oppositely arranged ball surfa¬ ce sections (3, 4) having the same curvature of the surface, whereby simultaneously at least one pair of the said oppositely arranged ball surface sections (4) possess the same centre (8) and possess a larger dis¬ tance to the centre (8) of the ball (1) than it is the case for the remaining pairs of ball surface sections (3).

5. Valve according to claim 1 , 2, 3, or 4, c h a r a c t e r i z e d in that the pair of ball shaped, conical or cylindrical surface sections (4) comprising no bores exhibit on the valve element (1 ) the largest distance to the centre (8) of the ball or to the axis (7) of the valve element, and that simulta¬ neously each surface section (3, 26) having a bore ex¬ hibits a smaller distance to the centre (8) of the ball or to the axis (7) of the valve element (1).

6. Valve according to claim 1, 2, 3, 4, or 5, c h a r a c t e r i z e d in that the sealing ring (7) at each of the connectable openings of the valve ca¬ sing facing the equatorial area (10) of the valve element (1) is fastened to the valve casing, whereby simultaneously the valve element (1) at the equatorial areas (3, 26) having bores • remains out of con¬ tact with the sealing ring (12).

7. Valve according to claim 4 or 5, c h a r a c t e r ¬ i z e in that the sealing ring (12) comprises a radially , inwardly directed projection (16) forming an obtuse angle with the surface (14) of the sealing ring (12) forming contact with the valve element (1).