NZ196627A - Isolating valve with leakage bleed-off - Google Patents

Description

NEW ZEALAND S.9.; 1 O .<■ f 9 7 Reg.19(4) ' / o uZ / # - Fee: $80.00 '"™ ' ^ "J v i priority Dats(cj ng'-'b-'&v complete Specification Filed: Class: '-8 SEP 198 | Publication Date: .. ^^ P.O. Journal F4o: PATENTS ACT 1953 Insert number Number: of Provisional Specification(s) , (if anv) and Date: date( s) of fi Ling; otherwise Leave bLank.

COMPLETE SPECIFICATION Insert Title ISOLATING VALVE WITH LEAKAGE BLEED-OFF of Invention.

Insert full name, • I/WK ROBERT MacGREGOR FAIRWEATHER, an Australian full street address and nationality of ... ^ r- „ ,, . . . . o i_ i_ i_\_ (each) applicant citizen of 54 Wentworth Avenue, Canterbury, in the State of Victoria, Australia hereby declare the invention for which I/we pray that a patent may be granted to me/us and the method by which it is to be performed, to -be particularly described in and by the following statement:- "ta. potent omaj i 22 MAY 1984 Indicate if following page is numbered '1(a)' RECEIVED i 9662 This invention relates to isolating valves of the type which will be referred to herein as a block and bleed valve. That is to say a valve for controlling fluid flow therethrough and having a bleed port for the purpose of allowing 5 harmless drainage of any fluid leaking past said valve.

The object of the invention is to provide an isolating valve of the above type which is efficient and effective in operation.

According to one aspect of the invention there is provided a block and bleed valve comprising a valve body including at least three ports, two of which are co-axial and the other of which is a bleed port, a valve element rotatabl.y 15 mounted in said body for co-acting with said ports, the valve element being such that, in one position thereof, fluid flow between and through said substantially co-axial ports is possible with the bleed port being sealed by said valve element, and in another position of the valve element, the 20 co-axial ports are sealed by said valve element and said bleed port is open to allow bleeding of fluids from the co-axial ports without mixing of the fluids within the valve body.

The invention also includes xjithin its scope a fluid handling system incorporating the block and bleed valve ||£PATEMT OffiCt : 2 2 MAY 1984 RECEIVED 1 966 2 according to the first aspect of the invention.

An embodiment of the invention will be described in greater detail, by way of example, reference being made to the accompanying drawings in which:- Figure 1 is a cross-sectional plan view of a block and bleed valve; Figure 2 is a cross-section taken on lines ABCD; Figure 3 is a schematic illustration of a typical application of the valve, and Figure 3a is a schematic illustration of the valve positions.

Referring to Figures 1 and 2 the valve 10 includes a body 11 and a rotatable valve element 12 20 sealingly mounted in the body. The body includes a pair of identical co-axial ports 13 communicating with one another through the open body. The valve element 12 includes a central shaft 14 having oppositely extending bosses 15 with sealing elements 16 mounted thereon. 25 Desirably the sealing elements 16 are resiliently mounted on Belleville washers 17 which act to urge the sealing NX PATENT * ■ | 22MAY1984 ii' | RECEIVED ; o r. s i 7 I ^ V U L. I elements 16 against the seat 19 surrounding the ports 13. The seat 19 is formed as a continuous smooth curved surface matching exactly the curvature of the sealing elements 16. As is best shown in Figure 2 the curved 5 sealing elements 16 follow the curved interior surface of the valve body 10 when moved in either direction as indicated by arrow A.

Figure 2 shows the valve element 12 positioned in sealing 10 relationship with the co-axial ports 13. A third port 18 is provided adapted in use to extend downwardly so that any leakage past the seals on either or both of the coaxial ports will be bled away. The bleed port 18 can be sealed by rotation of the valve element 12 a quarter turn 15 on' shaft 14 to bring sealing element 16 into sealing position over the bleed port. In this position both coaxial ports 13 are open and communicate with one another through the hollow valve body and will allow fluid flow whilst sealing the bleed port. The sealing elements 16 20 are hard plastics material such as nylon or teflon (trade mark) suitable for making an effective seal against the surface 19 and which is resistant to heat and corrosion.

Ihe isolating valve has application where a fluid is stored in a 25 plurality of containers but are connected into a conmon supply and discharge line. Furthermore, installation of the valve H2. PATENT OFRCt 2 2 MAY 1984 RECEIVED i 0 S / / .■ o allows in situ cleaning without risk of contamination during normal operation of the facility.

Figure 3 and 3a shows a typical such application of the valve.

Figure 3a shows schematically the two valve positions. In the left hand part of the Figure the valve is open with the sealing elements 16 shown in Figure 2 positioned vertically so that the bleed port 18 is closed. In the right hand part of the Figure the valve is closed and the sealing elements 16 take up a position similar to that shown in Figure 2 leaving the bleed port 18 open.

Tire valve is indicated by reference 10 connected into various supply, discharge and cleaning lines. Four tanks 20 are shown, however, it will be appreciated that any number may be connected into the common circuit in the same way. The drawing is annotated to indicate that each tank 20 is at a different stage of operation, namely, filling, storage, discharge and cleaning.

Referring to tank 20a the valves 10a and 10b are opened to allow flow through the co-'axial ports 13 from the product supply line 21 into the tank. The bleed port 18 is closed to prevent leakage of the supply fluid. frTPAravroFna | 2 2 MAY 1984 ■ li"i — fc rcCEfVe©, 6, 1 96627 The remaining valves 10c, lOd, lOe, lOf and lOg controlling cleaning fluid and discharge from the tank 20a are closed whereby the bleed port 18 is open to allow drainage of any leakage.

Supply line 22 is a supply line for cleaning fluid v7hilst lines 23 and 24 provide for discharge of cleaning fluid and product fluid from the tanks respectively.

It will be noted that valves 10c and lOg are positioned such that product fluid may be on one side and cleaning fluid on the other. It is imperative that inadvertent intermixing of the two fluids is avoided:' Thus the bleed port 18 having identical dimensions to the co-axial ports 15 will have the capacity to allow any leakage of either product fluid or cleaning fluid to drain away harmlessly through the bleed port virtually eliminating the possibility of build up of pressure in the valve and therefore the possibility of intermixing with fluid on the other side 20 of the valve.

By manipulating the valves in a predetermined sequence as illustrated it is possible to be simultaneously filling, emptying and cleaning the tanks in turn and it is also 25 possible to clean the lines between the valves and the valves themselves.

W2. PATENT QFPSq ■ 2 2 MAY 1984 RECEIVED ! Q\ t t 9 7 I ✓ U u L / In situ cleaning of the valve itself is possible through ducting 30 and connection 31 provided in the valve body shown in Figure 1.

MX PATIENT OFFICE 2 2 MAY 1984 RECEIVED

Claims (6)

i 96627 WHAT I CLAIM IS:

1. A block arid bleed valve comprising a valve body including at least three ports, two of which are co-axial and the 5 other of which is a bleed port, and a valve element rotat-ably mounted in said body for co-acting with said ports, the valve element being such that, in one position thereof, fluid flow between and through said substantially co-axial ports is possible with the bleed port being sealed by said 10 valve element, and in another position of the valve element, the co-axial ports are sealed by said valve element and said bleed port is open to allow bleeding of"fluids from the co-axial ports without mixing of the fluids within the valve body. 15 20

2. A block and bleed valve according to claim 1, wherein the valve body has a continuous substantially cylindrical sealing surface, and wherein the valve element includes seals matching the sealing surface.

3. A valve as claimed in claim 1 or claim 2 wherein the bleed port extends vertically downwardly and laterally relative to said substantially co-axial ports when in use and has identical dimensions to that of said substantially 25 co-axial ports.

4. A block and bleed valve substantially as and for the 1 96 6 2 - 9 - purpose herein described with reference to the accompanying drawings.

5. A fluid handling system including a plurality of stor-5 age containers interconnected with supply and drainage lines and controlled by a plurality of block and bleed valves as claimed in any preceding claim.

6. A fluid handling system substantially as herein 10 described with reference to the accompanying drawings. 15 20 ;B*7ENT(;22mm aecBVED;25;■£*.— J. D. HARDIE & CO. Patent Attorneys for the Applioant(s).