Improvements 66 in or relating to "Manhole," Handhole," and 66 Cleaning-hole" Covers for Metal Tanks and such like Vessels.
Year: 1888

page_text: Date of Application, 9th May, 1888
Complete Specification Left, 27th Sept., 1888
Complete Specification Accepted, 9th Nov., 1888
Improvements
66
in or relating to "Manhole," Handhole," and
66 Cleaning-hole" Covers for Metal Tanks and such like Vessels.
I, EDWARD ALBERT DAVIES, of The Crown Galvanizing Works, Wolverhampton
in the County of Stafford, galvanized iron manufacturer, do hereby declare the nature
of this invention to be as follows:-
:-
A "manhole" "handhole" or "cleaning-hole" cover for a metal tank or like vessel
such for instance as a water cart body or a circulating cylinder used in hot water
apparatus, as usually constructed, is formed sufficiently larger than the hole to enable
a joint to be made between itself and a margin, immediately around the hole, of the
sheet or plate through which the hole is formed, and the lid is fixed to the outside of
the tank or other vessel by means of set pins passing through the lid and screwed
into the body of the tank or other vessel; or the hole and lid are formed of an oval
shape so that the lid, which is made sufficiently larger than the hole to allow for a
proper joint, can be passed narrow-wise through the longer way of the hole, and the
joint is in this case made inside the tank or other vessel and the lid fixed by means of
a stud pin thereon passing through a loose bridge spanning the hole and bearing at
two or more places around the margin thereof, the pin being drawn up tightly, to
make the joint and fix the lid, by means of a nut on the outer end thereof bearing
against the upper side of the bridge. In each case it is necessary, especially if the
tank or other vessel is made of sheet metal or thin plate, to rivet a thickening or
strengthening ring around the hole, either (as the case may be) for the purpose of
receiving the ends of the set-pins, aforesaid, or of strengthening the metal around
the hole to prevent it springing between the points at which the bridge bears.
Now, the chief object of this invention is to obviate the necessity for rivetting a
ring around the manhole, handhole, or cleaning-hole, to avoid the use of set-pins, or
of a bridge, and to provide a simple and inexpensive lid which may be readily fixed
and removed, the employment of which involves a less projection from the tank or
other vessel than when a lid with a bridge is employed.-
For the purpose of this invention, the manhole, handhole, or cleaning-hole is formed
oval or elongated in shape; and, according to this invention the lid, which is of

page_text: the shape of the hole but, of course, larger to allow for proper bearing, consists
chiefly of two buckled or dished sheets or plates (hereinafter terms "dishes") of the
same size and shape, one for the inside of the tank or other vessel and the other for
the outside. A bolt is passed through the centre of one dish which is then placed
inside the tank or other vessel and turned into proper position to cover the hole,
and the other dish is then passed over the bolt and tightened up around the hole by
means of a nut on the bolt. The joint is made by means of rubber, asbestos, or other
suitable material, placed between the tank or other vessel and the bearing surface of
one of the dishes. The dishing of the inner dish is of course inwards, and that of
the outer dish outwards, so that as the nut is tightened up the dished parts are sprung
slightly towards one another and are thus held firmly under an elastic strain, and
the dishing affords the necessary strength to the parts and prevents them being drawn
against one another by the screwing up of the nut. No strengthening ring is
required around the hole, as the sheet or plate metal therearound is simply
compressed tightly all around between the bearing surfaces of the dishes, or rather
between the joint under the one dish and the bearing surface of the other, and cannot
therefore be sprung out of shape. In order to prevent the inner dish from being
turned out of position as the nut is being screwed up, the inner end of the shank or
stalk of the bolt may be square and pass through a square hole in the inner dish, and
a broad flat cross-bar, having a square hole through its middle be fitted just easily
around the square of the bolt so as to be in position between the two dishes, and is
preferably prevented from slipping off the bolt by means of a peg passed through
the bolt, and such cross-bar is formed of a length to bear slightly against the sides of
the manhole, handhole, or cleaning-hole, and with shoulders to fit between such sides,
so that when the bar is placed in the position indicated, after the inner dish has been
turned to cover the hole, it cannot turn either way and consequently the pin and
inner dish are also prevented from turning. A tight joint may be made around the
bolt by means of an elastic washer or other suitable packing placed between an iron
washer and the face of the outer dish.
The cross-bar aforesaid may be dispensed with by forming the inner dish with a
"raised" rim which fits easily within the manhole, handhole, or cleaning-hole, so as to
maintain the dish in its proper position, that is to prevent it from turning, whilst the
dishes are being fixed in place.
The dish between which and the tank or other vessel the joint is to be made may be
formed with a hollow around its edge to receive the jointing material, such for instance
as a rubber or asbestos ring.
When in the case of galvanized tanks and such like vessels a strengthening ring
is omitted around the manhole, handhole, or cleaning-hole, as is intended according to
this invention, the sheet or thin plate metal around the edges of the hole is liable to
be buckled or warped as a result of the galvanizing process, and when this is the case
such margin of metal is flattened again upon a cover of the above construction being
fixed as above described, in consequence of the sheet or plate being firmly compressed
between the two dishes as above described, and thus a good joint is readily made
notwithstanding the buckled or warped condition of the sheet or plate previously to
fixing the cover.
Dated this 8th day of Mon 1000

page_text: 66
Cleaning-hole", Covers for Metal Tanks and such like Vessels.
I, EDWARD ALBERT DAVIES, of The Crown Galvanizing Works, Wolverhampton
in the County of Stafford, galvanized iron manufacturer, do hereby declare the nature
of this invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement, reference being had
to the accompanying drawings and the letters of reference marked thereon (that is
to say):
"
A "manhole", "handhole " or cleaning-hole cover for a metal tank or like
vessel, such for instance as a water cart body or a circulating cylinder used in hot
water apparatus, as usually constructed, is formed sufficiently larger than the hole to
enable a joint to be made between itself and a margin, immediately around the hole,
of the sheet or plate through which the hole is formed, and the lid is fixed to the ont-
side of the tank or other vessel by means of set-pins passing through the lid and'
screwed into the body of the tank or other vessel; or the hole and lid are formed of
an oval shape so that the lid, which is made sufficiently larger than the hole to allow
for a proper joint, can be passed narrow-wise through the longer way of the
hole, and the joint is in this case made inside the tank or other vessel and the lid
fixed by means of a stud pin thereon passing through a loose bridge spanning the
hole and bearing at two or more places around the margin thereof, the pin being
drawn up tightly, to make the joint and fix the lid, by means of a nut on the outer
end thereof bearing against the upper side of the bridge. In each case it is necessary,
especially if the tank or other vessel is made of sheet metal or thin plate, to rivet a
thickening or strengthening ring around the hole, either (as the case may be) for
the purpose of receiving the ends of the set-pins, aforesaid, or of strengthening the
metal around the hole to prevent it springing between the points at which the bridge
bears.
'
A modification of this invention, which at present I prefer to employ, is illustrated
* manhole".
by the drawings on sheet 1 herewith, of which figure 1 is a plan of a
"handhole" or "cleaning-hole" in the top of a sheet metal tank, and of the inner
dished plate hereinafter described as forming part of the lid, and of the cross-bar
and central bolt hereinafter described; figure 2 is a transverse section on line xx
of figure 1; and figure 3 is a corresponding section, but shews, also, the outer dished
plate hereinafter described, and the lid to be screwed up so as to completely close
the hole. The hole A is of an oval or elongated shape. The lid consists chiefly of
two buckled or dished sheets or plates B B (hereinafter termed dishes) of. the same

page_text: size as one another, and both of the shape of the hole A, but larger so as to allow for
proper bearing, as shewn. The dish B₁ bears, when in position, against the inside of
the tank, and the dish B against the outside. A bolt C passes up through the centre
of the dish B', and such dish is passed narrow-wise through the hole A and is turned
into proper position to cover the hole, and the other dish is then passed over the bolt
and tightened up around the hole by means of a nut a upon the bolt. The joint is
made by means of felt, rubber, asbestos or other suitable material, placed between the
tank and the bearing surface of one of the dishes (preferably the outer dish). The
dishing of the inner dish B' is, of course, inwards as shewn, and that of the outer
dish outwards, so that as the nut a is tightened up the dished parts are sprung
slightly towards one another and are thus held firmly under an elastic strain, and the
dishing affords the necessary strength to the parts and prevents them being drawn
against one another by the screwing up of the nut. The bearing surfaces or
peripheries of the dishes are curved in section, as shewn, so as to expose a concave
surface to the surface upon which they bear, both for convenience of making the joint
between themselves, or either of them, and the tank, and to facilitate the slight move-
ment which takes place as the dishes are tightened up. No strengthening ring is
required around the hole, as the sheet or plate metal therearound is simply compressed
tightly all around between the bearing surfaces of the dishes, or rather (in the case
illustrated) between the joint under the one dish and the bearing surface of the other,
.and cannot therefor be sprung out of shape.
In order to avoid the necessity for holding up the bolt C whilst the dish B is being
placed in position, so as to prevent the dish B' from falling into the tank, and also to
enable the nut to be readily screwed up to tighten the joint without liability of the
dish B¹ being turned out of position, a cross-bar D is formed with a hole through its
centre by which it is slipped down over the bolt C, and this bar is notched on its inner
side at each end so that it may just fit easily between the sides of the hole A, as
shewn, but may be carried by the projecting parts cc, forming the upper sides of the
notches, on the edges of each side of the hole A. The unscrewed part of the shank of
the bolt C is formed square, or analogous shape, in section, and passes through
correspondingly-shaped holes in the dish B¹ and cross-bar D so that the bolt cannot
turn within such holes. A split pin or other cross pin is passed through the shank
of the bolt C in such position above the bar D that the dish B¹ may be passed through
the opening A into the tank and the bolt C then be turned so as to turn the dish B¹
into its proper position and the cross-bar into a position transverse to the hole A while
the cross-bar D is itself held up just above the top of the tank. The parts may
then be locked into the position shewn by figure 2 that is with the cross-bar I)
resting upon the sides of the hole and with the dish B' resting upon the bolt
which is itself supported by the pin 6 from the cross-bar D. The dish B may then
be readily passed down over the bolt C, and the nut a be then screwed up so
as to raise the dish B' against the underside of the top of the tank and securely
tighten up the joint. The bar D is, of course, prevented from turning by fitting
easily between the sides of the hole A, as shewn, and the bar itself prevents the bolt C
from turning. It is preferred to place a washer d between the nut a and the
dish B, and in order to make a tight joint around the bolt an elastic washer
or other suitable packing may be placed between the washer d and the face of
the dish B.
The dish between which and the tank or other vessel the joint is to be made may,
if desired, be formed with a hollow around its edge to receive the jointing material
such, for instance, as a rubber or asbestos ring, in lieu of forming a convex edge to
bear upon a flat packing.
When, in the case of galvanized tanks and such like vessels, a strengthening ring
is omitted around the manhole, handhole, or cleaning-hole, as is intended according
to this invention, the sheet or thin plate metal around the edges of the hole is liable to
be buckled or warped as a result of the galvanizing process, and when this is the case
such margin of metal is flattened again upon a cover of the above construction being

page_text: fixed as above described, in consequence of the sheet or plate being firmly compressed
between the two dishes as above described, and thus a good joint is readily made
notwithstanding the buckled or warped condition of the sheet or plate previously to
fixing the cover.
A further modification of this invention is illustrated by the drawings on sheet 2
herewith, of which figure 4 is a plan shewing the lid to be fixed in position upon a
tank, and figure 5 is a section on line y y of figure 4. In this modification the lid is
shewn to be of an oval or elongated shape, but this is not essential, as it may be round
or of other desired shape. The hole is formed by cutting out a piece of metal A¹ of
the desired shape, and this piece of metal forms the lid proper, though slightly smaller
than the hole itself. A channel section ring E¹ is fixed around the hole, and inside
the tank, by means of bolts e which pass up through such ring and through holes
formed therefor in the margin of metal around the hole from which the part A' has
been cut, or such bolts may pass up through the hole itself close to the side thereof.
The outer rim of the channel bears against the inner side of the tank, and the inner
rim thereof forms a ring projecting somewhat into the opening. The plate A¹, or lid
proper, when placed within the opening from which it was cut out rests upon the
inner rim of the ring E¹, as shewn by figure 5, and is firmly held in place and is
itself, together with the margin around the hole, strengthened by means of a grooved
ring E which is passed down over the projecting ends of the pins e and is tightened
down by nuts e so as to bear at the outer face of the tank and lid A' just as the ring E¹
bears against the inner face. As the nuts e¹ are tightened up they firmly compress
between the rings E and E¹ the margin of metal around the manhole and around the
lid A', and answer an analogous purpose to the dishes B B¹ of the former described
modification. This modification is suitable rather for tanks which are used for packing
goods for export and which require proportionately large manholes, and it will not
usually be necessary to make a watertight joint of the lid; but, if such is required, a
suitable joint may be made by means of felt or other packing placed under the rims of
one of the rings E or E¹, as will be readily understood. The ring E' is held in
position until the ring E is fixed, and also when the ring E is removed, by two or
more nuts f, which are covered by the ring E when in place; when the bolts e pass up
through the hole from which the plate A has been cut, the nuts f catch on the edge
of the hole. It will be seen that the opening into the tank is somewhat restricted by
the projection thereinto of the inner rim of the ring E'. This ring, however, may be
readily removed at any time, if desired, if the hole is of an oval or analogous shape
which permits of the ring being passed narrow-wise therethrough. If the ring is
circular in shape it must be placed within the tank before the sides and bottom and
top are all joined up.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I claim is :-
1. The improvements in or relating to manhole, handhole, and cleaning-hole, covers
for metal tanks, and such like vessels, substantially as described, for the purpose
set forth.
2. Forming a joint around a manhole, handhole, or cleaning-hole of a metal tank, or
such like vessel, by the aid of a pair of loose hollowed parts which are drawn towards
one another and, respectively, held firmly against the inside and outside of the tank, or
such like vessel, so as to compress the metal of such tank or vessel firmly between
them, substantially as described, for the purpose set forth.
3. The combination of a pair of dished plates with a bolt to tighten them, respectively,
inside and outside the margin of metal around the manhole, handhole, or cleaning-
hole of a metal tank or such like vessel, substantially as described, for the purpose
set forth.
4. In combination with a pair of dishes employed as described, the means by which
the inner dish is prevented from turning as the bolt by which the dishes are fixed is
tightened up.

page_text: 5. The combination of a sheet or plate fitting, or fitting approximately, within the
manhole, handhole, or cleaning-hole, of a metal tank or such like vessel, with a pair of
channel-section rings tightened, respectively, by means of bolts, inside and ontside
both such sheet or plate and the margin of metal around the hole, substantially as
described, for the purpose set forth.
6. The improvements in or relating to manhole, handhole, and cleaning-hole covers
for metal tanks, and such like vessels, substantially as described with reference to the
drawings berewith, for the purpose set forth.
Dated this 25th day of September 1888
STEPHEN WATKINS,
Wolverhampton and Walsall,
Agent for the Applicant.