Improved Means of and Apparatus for Clearing the Strums, Roses, or Perforated Suction Boxes of Pumps.
Year: 1889

page_text: Date of Application, 10th Dec., 1889
Complete Specification Left, 2nd June, 1890-Accepted, 19th July, 1890
PROVISIONAL SPECIFICATION.
Improved Means of and Apparatus for Clearing the Strums, Roses,
or Perforated Suction Boxes of Pumps.
We, ROBERT ALEXANDER FORSYTH, of Courtway, Gold-Tops, Newport in the
County of Monmouth Engineer and ALFRED HENRY DAVIES of Wilton Villa Caerau
Newport in the County of Monmouth Engineer, do hereby declare the nature of our
invention to be as follows :-
Our invention relates to the strums, roses, or perforated suction boxes of pumps
and has for its object the provision of means of, and apparatus for clearing the said
strums or suction boxes when choked, or blocked up by any solid material contained
in the liquid or water in which they are inserted.
It very often happens that considerable danger is incurred when the suction boxes
situated in the bilge of a vessel become choked with straw, grease, waste, or other
obstructive matter which is drawn into the holes of the said suction boxes by the
suction of the pumps. The same risk is also present in mines from the suction
pipes becoming choked and as in the case of either a ship or a mine the suction
boxes of the pump are often some feet below the surface of the liquid, or water
and entirely out of reach, it is a matter of great difficulty, and sometimes utter
impossibility to effect the clearing of the said suction boxes by ordinary means.
Our invention consists in arranging upon the suction pipe a suitable stop valve in
such a position as to be easily manipulated, and at a point in the suction pipe between
the said stop valve, and the suction box or directly into the suction box. We
introduce a steam pipe, or we may equivalently arrange a steam pipe in connection
with another water pipe in such a manner as to induce a stream of water to be
ejected from a nozzle. The action of the passage of steam through the suction
pipes or directly into the suction box in this manner is as follows:-
Should the orifices in the strum or suction box be so choked that the efficiency
of the pump is materially reduced owing to the accumulation of matter in the holes
or upon the outside of the strum, or suction box, by closing the stop valve in the
suction pipe of the pump and so stopping communication with the pump and admitting
steam to the suction pipe or box the water is forced therefrom by the steam, and
the stream of water escaping through the strum or suction box carries with it any
of the obstructive matter collected on the suction boxes and quickly moves any
obstruction that may have become fixed in the perforations.
We may also use the steam pipe surrounded by the other pipe in such a manner
that the steam being in the centre and issuing from the nose of the pipe shall induce
the current of water to be drawn from any convenient source, which stream being
directed in a direction towards the suction boxes shall more efficaciously remove any
obstructing material on account of the higher initial force exerted by the water in
comparison with the steam.
FELL & WILDING,
1, Queen Victoria Street, E.C., Agents for the Applicants.
COMPLETE SPECIFICATION.
Improved Means of and Apparatus for Clearing the Strums, Roses,
or Perforated Suction Boxes of Pumps.
We, ROBERT ALEXANDER FORSYTH, of Courtway, Gold-Tops, Newport, in the
5 County of Monmouth, Engineer, and ALFRED HENRY DAVIES, of Wilton Villa, Caerau,
Newport, in the same County Engineer, do hereby declare the nature of our invention

page_text: and in what manner the same is to be performed to be particularly described and
ascertained in and by the following statement :-
Our invention relates to the strums, roses, or perforated suction boxes of pumps,
and the pipes and valves leading thereto, and has for its object the provision of
means and apparatus for clearing the said strums, suction boxes, pipes and valves
when choked, or blocked up by any solid material contained in the liquid or water
passing through them, or in which they are inserted.
It very often happens that considerable danger is incurred when the suction boxes
situated in the bilge of the vessel become choked with grease, waste, ashes or other
obstructive matter which is drawn into the holes of the said suction boxes, pipes, and
valves by the suction of the pumps.
The same risk and cause of stoppage is also present in mines from the suction pipes
becoming choked, and as in the case of either a ship or a mine the suction boxes
are very often some feet below the surface of the liquid or water and entirely out of
reach it is a matter of great difficulty and sometimes utter impossibility to effect the
clearing of the said suction boxes by ordinary means.
Our invention consists in introducing into the suction pipe, suction valve box, or
strum, a pipe leading from any convenient steam service so that upon allowing live
steam to enter through the said pipe into the suction pipe, suction valve box, or strum,
a very effective clearing action is set up, first by the internal pressure tending to
force the obstruction outwards through the holes in the strum, secondly by an inter-
mittent and violent action caused by the steam condensing in the pipe producing a
vacuum, so filling the pipe with water, the vacuum being destroyed in a short time
by the continuous supply of steam, the water is forced from the suction pipe through
the strum until the steam meeting further cold water a vacuum is again produced
giving a reflux action; and thirdly, the parts choked being raised to a considerable
temperature by hot steam, the coagulating medium, which is usually in the form
of grease becomes melted, and the round lumps or balls, which form by the rolling
action in the strum, become broken up, so as to be capable of being blown out
through the perforated holes of the strums, or drawn up through the valves of the
pump and discharged.
In order that our invention may be the better understood we will now proceed to
describe one method of carrying our invention into effect in relation to the drawings
hereunto annexed, reference being had to the letters and figures marked thereon.
Figure 1 shows an ordinary multiple bilge suction box, and valves, showing the
various water connections, and also a convenient method of applying steam by means
of a multiple wayed cock, distributing steam to either one or other of the suction
pipes, valve boxes, or strums.
Figure 2. shows a plan of the same.
In Figure 1 the box A is common to all the valves a, a', a², a³, & a* and has a
connection B leading to the suction valve of a pump, the valves as shown are of the
non-return type, that is to say they are capable of being closed by screwing the
spindle 6 down upon them but are detached therefrom so that when the spindle is
screwed up in an opened position the valves are free to open and close at each
pulsation of the pump.
Suitable branches C C C C³ & C are provided in the lower part of the box each
forming a separate suction service from a different part of the vessel.
A multiple-wayed cock D preferably of the form in which the plug has an open
end, and one side port is arranged so that each branch d d d² d³ & d² communicates
with the suction pipes C C C C³ & C by means of the branches c c c² c³ & c¹
respectively.
Live steam is led from any convenient source to the cock D through the branch d³;
should now the suction pipe, or strum of either one of the suction services become
choked or blocked (take C for instance) the valve a is closed, and the plug of the
cock D is placed so that its side port communicates with the branch d leading
through the pipe c to the suction pipe C allowing the steam to enter the suction

page_text: pipe and blowing out any obstruction there may be therein or around the perforated
sides of the strum.
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Should any obstruction lodge upon the seating of the bilge suction valve, or the
suction valve of the pump the valve may be slightly opened and the steam allowed to
blow up, heating the valve and so dissolving the obstruction should it be of a greasy
or similar nature.
Where the bilge suction valves are not of the non-return type but are capable of
being lifted by the spindle when the latter is screwed up in its upper or opened
position we may merely use one inlet for the steam entering the box A above instead
of below the suction valves. It will then be preferable to arrange a stop valve or
cock between the valve of the suction box and the pump, so that by shutting this
latter valve or cock anyone or other of the suction valves can be lifted so as to direct
the steam from the steam cock in the top of the box to any one or other of the suction
pipes.
It is obvious that the same result can be attained as before described by arranging
a separate steam cock upon each bilge suction box, bilge pipe, or a pipe leading to
the strum or rose..
We have found by experiment that upon admitting steam to the suction pipe or
box when choked the water is forced therefrom and the stream of water escaping
through the strum or suction box carries with it the obstructive matter collected
within the said pipe, and box and upon the outside of the perforated sides of the
latter and quickly removes any obstruction that may have become fixed in the
perforations.
In some cases we use the steam pipe, surrounded by a water service pipe, in such
a manner that the steam being in the centre and issuing from the nose of the pipe a
current of water is introduced from any convenient source and is set in motion at a
considerable velocity, the steam being directed towards the suction box, so as to more
efficaciously remove any obstructing material by reason of the considerable initial
force exerted by the water set in motion by the steam.
Our arrangement is also very useful where the pump is situated at a considerable
height above the liquid to be pumped as by filling the suction pipe with a small
amount of steam a vacuum is produced thereby charging the suction pipe with liquid.
This obviates the clumsy and unsatisfactory method often employed of filling the
suction pipe by means of a funnel, when the pump fails to catch the water.
Where very high pressures of steam are used it may be necessary to pass the said
steam through a reducing valve before its introduction into the suction services.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is :-
1st. The method of clearing the strums rose boxes, suction valves and pipes of
pumps, by the introduction of live steam into the same substantially as described.
2nd. In such a method of clearing the strums, rose boxes, suction valves and pipes
of pumps, a pipe and cock leading from any live steam service in combination with
the suction service of the pump, for the introduction of live steam to the said suction
service.
3rd. In such a method of clearing the strums, rose boxes, suction valves and pipes
of pumps, the combination of a multiple-wayed cock in communication with a live
steam service, with a multiple bilge suction box, containing suction valves, each
separate branch of the said multiple-wayed cock being connected to one of the
separate suction services from the said bilge suction box, substantially as and for the
purposes set forth.
Dated thin and 1 1900
FELL & WILDING,
Agents for the Applicants.