Improvements in or relating to the Coverings of Hand Holes in Steam Chests, Headers, Boilers, Economisers, or other Vessels.
Year: 1892

page_text: Date of Application, 9th Mar., 1892
Complete Specification Left, 8th Dec., 1892-Accepted, 14th Jan., 1893
PROVISIONAL SPECIFICATION.
'
Improvements in or relating to the Coverings of Hand Holes in
Steam Chests, Headers, Boilers, Economisers, or other Vessels.
I, JOHNSON MILLS of Swinton Park Manchester, in the County of Lancaster
Engineer do hereby declare the nature of this invention to be as follows:-
This invention relates to the coverings for hand holes for use in steam chests,
headers, boilers, economisers, or other vessels in which pressure is contained, and
the object of this invention is to construct a cap or corer with a shank or shanks
formed thereon in one piece, by which a perfectly tight joint may be obtained, and
in the event of any defect in the several parts in connection with cover will
prevent the sudden outflow or explosion of steam or other contents through said
hole.
In this invention I form the hand hole in the boiler or other vessel, preferably
of an elongated or oblong form. I place round near the edge and on the inner side
of said hole, or on the claw edge of clamp hereinafter described, a ring of asbestos
or other suitable packing material; I form a clamp of a convex form with a claw
edge of an elongated or oblong shape corresponding to the shape of hand hole but
somewhat larger than said hole so as to form an internal cover terminating with a
shank or spindle.
I insert the aforesaid convex end into the boiler or other vessel by passing the
narrow part of convex end through the wider part of hand hole and then turning
the convex end round so that the claw edge rests on the ring of asbestos or other
packing hereinbefore described, with the shank passing through the hole to the
outside and terminating in a screwed end.
I form the centre portion of shank, by turning said shank so as to fit thereon a
cap or cover, or cross bar to the outside of hand hole, with the edges of said cover
resting on the outer edge of hand hole.
The screwed end of shank is of smaller diameter than the hole in aforesaid
clamp, so as to pass easily through said hole. I secure the hereinbefore described
convex end of clamp that is placed over hand hole on the inside of vessel, and also
the cap that is placed over the outside of hand hole, by means of a nut fitted on
screwed end of shank or spindle, which when tightened effectually prevents any
escape of steam or other contents by compressing the aforesaid ring of asbestos or
other packing material between the claw edge of clamp and the inside of plate of
boiler or other vessel.
By these means the effect of increased pressure in the boiler or other vessel is
to cause a tighter joint, irrespective of any defect in the bolts, screws or other
parts in connection with cover, or the destruction of the outside cover as the convex
form of the internal cap or cover would prevent the sudden explosion of steam.or
outflow of contents.
THOMAS PRESCOTT,
53, Arcade Chambers, St. Mary's Gate, Manchester,
Agent for Applicant.
COMPLETE SPECIFICATION.
Improvements in or relating to the Coverings of Hand Holes in
Steam Chests, Headers, Boilers, Economisers, or other Vessels.
I, JOHNSON MILLS of Swinton Park, near Manchester, in the County of
Lancaster, Engineer, do hereby declare the nature of this invention and in what
Price 8d l

page_text: manner the same is to be performed, to be particularly described and ascertained in
and by the following statement :-
This invention relates to the coverings for hand holes, for use in steam chests,
headers, boilers, economisers or other vessels in which pressure is contained, and
the object of this invention is to construct a cap or cover with a shank or shanks
formed 'thereon in one piece, by which a perfectly tight joint may be obtained, and
in the event of any defect in the several parts in connection with cover will.prevent
the sudden outflow or explosion of steam or other contents through said hole.
I attain this object by the means hereinafter described and as illustrated in the
accompanying sheet of drawings in which
Fig. 1 is a plan view and Fig. 2 a sectional view of a cap or covering for hand
hole constructed according to my invention.
↓
I form the hand hole b in the boiler or other vessel preferably of an elongated or
oblong form.
I place round near the edge b' and on the inner side of said hole or on the claw
edge al of clamp a hereinafter described, a ring of asbestos c or other suitable packing
material.
I form the clamp a of a convex form with the claw edge a¹ of an elongated or
oblong shape corresponding to the shape of hand hole d but somewhat larger than
said hole so as to form an internal cover terminating with a shank or spindle e.
I insert the aforesaid convex end into the boiler or other vessel, by passing the
narrow part of convex end through the wider part of hand hole d and then turning
the convex end round so that the claw edge a¹ rests on the ring of asbestos c or
other packing hereinbefore described with the shank or shanks e passing through
the hole d to the outside and terminating in a screwed end or ends e'. I form the
centre portion of shauk e by turning said shank so as to fit thereon a cap or cover
or cross bar to the outside of hand hole, with the edges of said cover resting on
the outer edge of hand hole. The screwed end e' of shank e is of smaller diameter
than the hole in aforesaid clamp f so as to pass easily through said hole.
I secure the herein before described convex end of clamp that is placed over
hand hole on the inside of vessel and also the cap that is placed over the outside of
hand hole, by means of a nut e² fitted on screwed end of shank or spindle which
when tightened effectually prevents any escape of steam or other contents by
compressing the aforesaid ring of asbestos or other packing material between the
claw edge of clamp and the inside of plate of boiler or other vessel.
i
By these means the effect of increased pressure in the boiler or other vessel is to
cause a tighter joint. irrespective of any defect in the bolts, screws, or other parts
in'connection with cover, or the destruction of the outside cover, as the convex
form of the internal cap or cover would prevent the sudden explosion of steam, or
outflow of contents.
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:-
Covering the hand holes in steam chests, headers, boilers, economisers or other
vessels by the use of a hollow clamp or cover of a convex form such as a with a
shank or shanks such as e formed thereon in one piece in the manner and for the
purpose substantially as herein before described.
Dated this 7th day of December 1892.
THOMAS PRESCOTT,
53, Arcade Chambers, St. Mary's Gate, Manchester,
Agent for Applicant.