GB2588921A

GB2588921A - Marine service tool

Info

Publication number: GB2588921A
Application number: GB1916550.5A
Authority: GB
Inventors: Gregory Marshall Victor
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-11-14
Filing date: 2019-11-14
Publication date: 2021-05-19
Also published as: GB201916550D0

Abstract

A marine service tool for replacing the seacock valves of a boat or vessel while in the water includes a tool body 6 with means of direct, or indirect attachment 7 to a seacock valve, a placement tube 10 that can be assembled in sections and can slide through a ring seal 9 to precisely place a deformable bung 13 in the bore of a through hull fitting of a boat when the seacock valve is open while maintaining the flooded tool body sealed against the external water pressure and the means of securing the tube 10 through the tightening of a seal retaining ring 8 and deforming the bung once located, by a tension element 14 and a tensioning part 16, so as to form a secure seal in the fitting to allow for the tool body 6 and its associated sealing components 8,9 to be dismantled in situ and removed, the defective seacock valve extracted and a replacement valve fitted under controlled conditions, in accordance with best pipework connection practice and without time pressures or constraints or any period of uncontrolled water flow through the pipework.

Description

MARINE SERVICE TOOL

DESCRIPTION

Marine Service Tool -Seacock Replacement This invention relates to a tool and methodology for the controlled removal of a primary seacock block valve in a vessel while afloat and with the pipework under external hydrostatic pressure and the fitting of a replacement valve in accordance with best industry practice while avoiding any water free flow into the vessel and maintaining the pipework system sealed throughout all stages of the complete replacement operation.

Through hull penetrations in boat hulls provide the essential means of allowing water to flow into or out of the vessel's pipework systems. The holes made for these penetrations are sleeved and strengthened with secured fittings to which are attached block valves called seacocks and are necessary to provide an essential means of maintaining hull integrity. These seacock valves are subject to degradation by wear, corrosion and marine growth and need to be replaced from time to time.

Seacock valves set immediately adjacent to the through hull fitting of a boat hull provide the primary block against the external head of water pressure acting on them and cannot be isolated to allow for their replacement.

The replacement of seacock valves presents additional challenges in that they are frequently 1 Located in very confined and awkward places such as bilges and small toilet cupboards spaces.

2 Associated with restricted access.

3 Set in the vicinity of other pipework and valves which severely limits the space available for the use of tools required for their replacement.

These conditions combine to increase the risk of uncontrolled flow of water into the vessel when they are removed while the boat is in the water and the ability to fit a replacement valve safely and securely and in accordance with good practice is compromised by their awkward locations.

Uncontrolled flow of water arising from the removal of these primary block valves in a confined space carries the significant risk of flooding the vessel.

For these reasons it is normal practice to lift the vessel from the water and complete the operation with the boat on hard standing.

However, the lifting of a boat out of the water requires a special docking facility and lifting equipment which is not always available at the required time. Furthermore, lift in and out is a costly operation with a typical charge running into hundreds of pounds for a small boat.

A safe and secure means of accomplishing a seacock valve replacement in the water is therefore attractive and some alternative methodologies may be adopted Current alternative means of replacing a seacock valve of a boat in the water include.

a) Removing the old valve and fitting the new one quickly onto the open ended threads of the through hull fitting against the uncontrolled free flow of water entering the boat b) Diving over the side of the boat and inserting a wooden bung into the outside of the through hull fitting and removing this after replacement of the internal valve c) Using a proprietary flexible rubber plunger with a long stalk and 'mushroom' type head inserted from inside the boat and through the opened valve and against the free flowing water ingress and drawing the circular 'mushroom' head back against the outside of the hull to form a temporary seal and relying on the external water pressure to hold the tool in place.

All these methodologies have serious limitations, can be time constrained and carry the significant risk of experiencing a loss of control of free flowing water flow into the boat.

In addition and specifically Procedure (a) is fundamentally haphazard and does not allow for the essential application of PTFE sealing tape to be wound into the threads of the through hull fitting prior to mating the new valve in order to make a watertight joint in the threads between fitting and valve since the old valve has to be removed and the replacement fitted in seconds to limit the period of uncontrolled water flow into the vessel.

Procedure (b) requires access to the bore of the through hull fitting from the outside of the boat to insert a wooden bung but many through hull inlet fittings have integral strainers on the outside where the insertion of a bung from the outside is not possible Figure 2(2) Procedure (c) is also limited to valves screwed onto open ended fittings because the plunger has to be pushed out through the hull and drawn back against its outside surface and it is therefore not suitable for fittings with strainers or anodes fitted to the outside nor to fittings with rough marine growth on the outside which will adversely affect its ability to make a seal. In addition, there is a serious risk of flooding associated with the removal of the defective valve because of the uncertainty when inserting the plunger into the open end of a free flowing open through hull fitting that it will in fact seal effectively. The precarious seal obtained must then be maintained throughout the unscrewing of the defective valve and re-fitting the new one without disturbing the plunger as sealing tape is wound into the threads of the fitting.

To overcome the limitations and problems, as described, the present invention provides a means of completing the controlled removal and replacement of a seacock valve on all types of through hull fittings, including those with strainers and anodes fitted, entirely from the inside of the hull wall and with no free flow of water arising at any time due to the fact that a continuous seal is maintained throughout against the external head of water pressure while the old valve is removed and replaced with a new one. Because the pipework is always sealed and the operation is under control at all times the threaded joint between the fitting and new valve can be made carefully with the necessary thread sealing tape wound onto the fitting as cannot be achieved when the same work is conducted with open free flowing pipework or an unreliable external seal.

The proposed invention provides the means for fixing a tool body, encasing a bung made of deformable material and affixed, but interchangeable according to the valve size, to the end of a tube which may pass through the tool body, to the fixing end of a closed defective valve once the hose connector has been removed. The valve can then to be opened, the tool body flooded and the uncompressed deformable bung, sized according to the internal diameter of the pipework in question, pushed through the opened valve and into the bore of a through hull fitting to a pre-determined location while a watertight seal is maintained between the inside of the tool body and the outside of the sliding tube by a ring seal held in place by a seal retaining ring that can be tightened or loosened so as to increase or decrease the efficacy of the ring seal and the degree of freedom that the tube has to slide through the ring seal.

The invention provides for the deformable bung to be precisely located in the bore of the through hull fitting and then to be deformed by the action of screwing or unscrewing a tensioning part at the top of the tube to act on a tension element and induce a compressive force in the tube so as to pull the underside of the bung against the bottom end of the tube and axially compress the bung and increase its diameter to effect a secure and reliable seal between the bung and the bore of the fitting so that the tool body and ring seal arrangement of the invention may be dismantled and removed leaving only the deformed bung, tube and tension element and tensioning part in place and the fitting securely sealed to allow for the defective valve to be removed and a replacement fitted over the tube and threaded onto the fitting with sealing tape in accordance with good practice.

The invention provides for the tool body then to be re-fitted to the replacement valve and the ring seal and seal retaining ring to be replaced, the tensioning part to be screwed or unscrewed to release the compression on the bung and free it so that the sealed tool body floods and the tube may be withdrawn, after easing the tightness of the seal retaining ring, through the new valve and into the tool body while the ring seal arrangement checks water ingress from the flooded tool body until the new valve is closed. The tool is then removed from the valve to complete the replacement.

The tube may be segmented and incrementally extended as it is pushed into and through the valve body to facilitate the tool's use in confined spaces and its use for larger valves where the length of the tube to be inserted is greater than access available for a longer tube.

The cable used for the tension element may have a straight rigid section at its upper end Figure 3 (14a) to facilitate the threading of the cable through the bung and placement tube.

The tension element may be a solid rod or a cable and may incorporate a threaded section at its upper end Figure 5 (14c) where it passes out of the end of the tube to allow for the tensioning force to be applied in the tension element by a tensioning part such as a threaded nut Figure 5 ( 16c).

The fixing section of the tool Figure 3 (7) may be threaded or have bolted flange plate and the tool may be fixed to the valve body via an intermediate reducing bush, if necessary, to allow for the tool to be used on a wide range of valve sizes.

The deformable bung of the tool may be interchangeable and sized for each application according to the diameter of the pipework and seacock valve to be replaced.

The invention will now be described by way of an example and with reference to the accompanying drawings in which for the variant described Figure 1 shows a drawing of a typical seacock ball valve (1) and a through hull fitting (2) without external strainer Figure 2 shows a section through a typical arrangement of a through hull inlet pipework assembly and comprises a fitting with external strainer (3) that penetrates the hull material (5) connected to a seacock block valve (1) to which is fitted a hose connector (4).

Figure 3 shows a section through one variant of the invented tool and comprises A tool body (6) with a threaded connection section(7), a screw down seal retaining ring (8) securing a ring seal(9) having a central bore through which a tube (10), comprising one or more sections, with an adjustable sliding marker ring around it (11), may move or be held depending upon the torque applied to the seal retaining ring (8) and which tube, at its bottom end, is fixed onto a plate (12) set on to the surface of a bung made of deformable material (13), a tension element (14) that passes through the inside of the tube (10) and deformable bung (13) and is affixed to a plate (15) at its lower end and underneath the deformable bung (13) and through a tensioning part at its upper end being either a stud (16a) or a nut (16b) set into or onto the tube respectively and which tension element (14) has its effective length fixed above the stud(16a) or nut (16b) by a cable gripper (17) bearing on a washer(18) such that the tensioning part (16a or16b) can be screwed out from the tube to act against the gripper(17) and apply a tensile load in the tensioning element(14) between the underside of the bung and the top of the tube so as to deform the bung material (13) and increase its diameter to make contact with the internal bore of the through hull fitting to form a watertight seal.

The tube(10) may comprise a single piece or preferably a series of threaded sections that can be joined together incrementally to accommodate a range of valve sizes and facilitate installation of the tool in situ in places of restricted access.

The connection section (7) may comprise a mating thread or a bolted flange plate as appropriate to the design of valve in question The tension element (14) may comprise a rod or a cable the latter being preferred for use in very restricted spaces because its effective length can be varied in situ in accordance with the required placement tube length and its flexibility requires less space and clearance access for the installation of the tool Alternatively, the tensioning part (16a / 16b /16c) may incorporate a lever and cam arrangement that applies the tensile load as the cam is rotated by the lever and acts by increasing the distance between the top of the tube and the underside of the cable gripper.

The deformable bung (13) is interchangeable and sized according to the diameter of the pipework in question to allow it to pass through the valve when undeformed and form a seal in the through hull fitting when a compressive load is applied axially Figure 4 shows a section through a variant of the tool in which the tensioning part (16b) is a nut which is screwed against the underside of the cable gripper to induce a force in the tension element Figure 5 shows a section through a variant of the tool in which the tension element has a threaded section (14c) where it emerges from the tube and the tensioning part is a nut (16c) which is screwed down the element and against a washer set on the tube to induce a tensile force in the tension element and a compressive force in the tube.

Figure 6 shows the tool fitted to a closed seacock valve(1) after removal of the hose connector (Figure 2 (4) ) with the tensioning part stud alternative (16a) in the top of the tube (11) screwed in and the deformable bung(13), sized to pass neatly through the seacock valve bore in its relaxed state and the seal retaining ring (8) tightened to seal the tool body(6) and the sliding marker ring (11) positioned against the seal retaining ring ready for placement at the required location in the through hull fitting once the valve is opened.

Figure 7 shows the seacock valve(1) open and the tool tube(10), with the tensioning part(16a) still screwed in, the tension element unloaded and the bung (13) undeformed and the tightness of the seal retaining ring(8) having been eased to allow the tube (10) to slide through the ring seal(9) and the bung(13) to be pushed through the open valve into the bore of the through hull fitting(3) to the location as pre-determined and confirmed by the position of the sliding marker ring (11) touching the top of the seal retaining ring(8) Figure 8 shows the tool inserted through the open valve as per Figure 5 with the tensioning part(16a) screwed out to apply a force through a washer (18) against the underside of the cable gripper(17) secured onto the tension element (14) and the deformed bung(13) securely set in the internal bore of the fitting (3) Figure 9 shows the through hull fitting (3) with the deformed bung (13) secured and tube (10) in place but with the marker ring, tool body, ring seal and seal retaining ring removed and with the defective valve also removed ready for the placement of the new valve over the tool tube Application Methodology for a seacock valve with threaded connection In order to change a seacock valve using the invention while the boat is in the water an appropriate size of deformable bung with plates Figure 3(12,13,15) according to the diameter of the valve to be replaced is fitted to the lower end of the tension element Figure 3 (14), the element threaded or fitted through the required section(s) of the placement tube Figure 3 (10) with the aid of a rigid section if fitted Figure 3 (14a) and the cable gripper Figure 3 (17) fixed onto the cable above a washer Figure 3 (18).

The attachment part of the tool Figure 3 (7) may be fitted via a reducing bush screwed into the valve body so that a standardised version of the tool can accommodate a range of valve sizes. The tube Figure 3 (10), with tool seal retaining ring Figure 3 (8) loosened, is withdrawn to pull the bung assembly (12,13.15) into the tool body and the sliding marker ring (11) pushed down onto the sealing retaining ring (8).

Where access is restricted a single length of tube only may fitted and extended incrementally with the tool in place on the valve and as the tube is pushed into the valve body.

As a first step and in order to determine the correct depth required in through hull fitting, the tool is fitted to the replacement (new) valve to be installed via an intermediate reducing bush interface, if necessary.

The tube (10) is then pushed right through the opened new valve to the desired location beyond the blocking gate or ball of the valve.

The marker ring (11) is pushed down onto the seal retaining ring (8) and fixed so as to record the determined depth of penetration.

The tube (10) is then fully withdrawn with the marker ring in situ on the tube to act as the positioning guide for the next step. The seal retaining ring is tightened and the tool removed from the new valve body.

The seacock valve to be replaced (old valve) Figure 2 (1) is closed and the hose and hose connector fitting Figure 2 (4) removed to expose the internal threads of the valve body. The tool body with tube Figure 6 (10) fully withdrawn and tube held in place by the tightened seal retaining ring Figure 6 (8) acting on the ring seal (9) is inserted and screwed directly into the body of the 'old' valve Figure 6 (1) or into the selected reducing bush and onto thread with sealing tape to ensure a watertight connection.

The seacock valve Figure 7 (1) is then opened and the tool flooded. The seal retaining ring Figure 7 (8) tightness is eased to allow the placement tube Figure 7(10) to slide through the ring seal Figure 7(9) and for the bung assembly Figure 7 (12,13,15) to be pushed through the open valve until the previously set marker ring Figure 7 (11) contacts the top of the seal retaining ring Figure 7 (8) and the bung is thus known to be located at the pre-determined required position in the bore of the through hull fitting Figure 7 (3). The seal retaining ring (8) is tightened The deformable bung material Figure 8 (13) is then compressed between the tube bottom plate Figure 8 (12) and the plate of the tension element Figure 8 (15) by unscrewing the tensioning part Figure 8 (16a) or nut Figure 4 (16b) to push against the underside of the cable gripper Figure 8 (17) and tube top and thus expand the bung diameter so as to make the seal into the through hull fitting Figure 8 (3).

The marker ring Figure 8 (11) is then removed by loosening it and sliding it up and off the placement tube The seal retaining ring Figure 8(8) is loosened gradually to check that the bung seal in the fitting is sound as confirmed by the rigidity of the tube and the lack of water ingress before it is removed followed by the ring seal Figure 8 (9) and the tool body Figure 8 (6) leaving only the tube, bung and tensioning element and associated parts in place Figure 9.

The old seacock valve can then be removed without water ingress and replaced with a new open valve by passing both units over the fixed tube Figure 9 (10) and a watertight seal is assured by the application of thread sealing tape to the exposed threads of the through hull fitting Figure 9 (3).

The tool body is then inserted into the newly fitted valve body, the ring seal replaced around the placement tube and secured with the seal retaining ring The bung is decompressed, by screwing the tensioning part down the tube, flooding the tube body which is sealed onto the tube by the ring seal. The seal retaining ring tightness is eased to allow the tube to be fully withdrawn out of the valve body to the position as shown in Figure 6 and the new valve closed.

The tool is removed to complete the operation

Claims

CLAIMS1. A tool for the replacement of a seacock valve while under the external hydrostatic pressure of the water acting on a vessel while afloat comprising a means for attaching the tool to the seacock block valve directly or via a reducing bush, a means of blocking the ingress of water into the vessel, when the seacock valve is opened and the tool flooded, by the action of a ring seal and a deformable bung sized so that it can pass through the open bore of the valve be precisely placed by a tube in the bore of the seacock through hull fitting and then deformed to provide a secure seal against the inflow of water when the seacock valve is removed.
2. A tool for the replacement of a seacock valve while under hydrostatic pressure according to claim 1 in which the means is provided to allow for a deformable bung to be pushed through the open seacock valve to be replaced by a placement tube in contact with and sealed to the upper surface of the bung
3. A tool for the replacement of a seacock valve while under hydrostatic pressure according to claim 1 in which the ingress of water is blocked, when the placement tube is moved through the flooded open valve, by the action of a ring seal held in place by a seal retaining ring
4. A tool for the replacement of a seacock valve while under hydrostatic pressure according to claim 1 in which the required location of the deformable bung in the bore of the through hull fitting can be achieved precisely by means of a marker ring which can slide along or be fixed to the outside of the placement tube.
5. A tool for the replacement of a seacock valve while under hydrostatic pressure according to claim 1 in which the degree of grip and sealing between the placement tube and the ring seal can be varied by adjusting the tightness applied to the seal retaining ring to vary the force on the ring seal.
6. A tool for the replacement of a seacock valve while under hydrostatic pressure according to claim 1 in which the deformable bung can be compressed though its thickness to expand its diameter by the action of a tension element which squashes the bung against the bottom of the placement tube.
7. A tool for the replacement of a seacock valve while under hydrostatic pressure according to claim 1 in which the tension element may be a rod or cable and which may have a threaded section to allow for a tensioning part to be screwed along that section to induce a compressive force in the tube.
8. A tool for the replacement of a seacock valve while under hydrostatic pressure according to claim 1 in which the force in the tension element is provided by a tensioning part acting to induce a compressive force in the tube.
9. A tool for the replacement of a seacock valve while under hydrostatic pressure according to claim 1 in which the deformable bung provides a reliable and secure seal against the ingress of water when placed inside the through hull fitting and deformed.
10. A tool for the replacement of a seacock valve while under hydrostatic pressure according to claim 1 in which the seal retaining ring and ring seal and tool body can be removed completely after the deformable bung is set and deformed without the ingress of water past the secured bung.
11. A tool for the replacement of a seacock valve while under hydrostatic pressure according to claim 1 which provides for the removal and replacement of a defective valve with a new unit that can be fitted over the placement tube and tensioning element.
12. A tool for the replacement of a seacock valve while under hydrostatic pressure according to claim 1 which can be reassembled onto the new replacement valve and the placement tube withdrawn through the open new valve after the deformable bung is returned to its undeformed state to permit the closure of the new valve.
13. A tool for the replacement of a seacock valve while under hydrostatic pressure according to any of the preceding claims, in which the security of the set bung and its resistance to being dislodged by the external water pressure be varied according to the tensile load applied to the tension element.
14. A tool for the replacement of a seacock valve while under hydrostatic pressure according to any of the preceding claims in which the placement tube may be constructed from sections that can be assembled in situ from its component parts so as to minimise the space and clearance required for its application
15. A tool for the replacement of a seacock valve while under hydrostatic pressure according to any of the preceding claims that eliminates any period of free flow water ingress into the vessel while the seacock valve is open.
16. A tool for the replacement of a seacock valve while under hydrostatic pressure that provides for the making of a sound and sealed connection between the existing through hull fitting and new replacement valve through the careful use of thread sealing tape.