Improvements in Mine Shafts, Well Linings, Chimney and other. Shafts, and Apparatus for Construoting the same.
Year: 1894

page_text: Date of Application, 15th May, 1894'
Complete Specification Left, 15th Feb., 1895-Accepted, 11th May, 1895
PROVISIONAL SPECIFICATION.
Improvements in Mine Shafts, Well Linings, Chimney and other.
Shafts, and Apparatus for Construoting the same.
I WILLIAM SPIERS FREEMAN Invicta Works Otford Kent Civil an 1.
Mechanical Engineer, do hereby declare the nature of this invention to be as
follows:--
Mine shafts, well linings and chimney shafts have hitherto been chiefly con-
structed of brickwork but in my invention I construct them of cement concrete by
means of improved moulds as herein set forth by which they are made monolithic
and impervious, and of great strength and smoothness (both within and without)
so that unlike brickwork they have in the case of mine shafts and well linings little
tendency to become earth bound in sinking.
In sinking a shaft by my method a strong cast iron curb or ring is laid upon
the ground and the mould (consisting of two cylinders) is fixed thereon; the
annular space between the two cylinders is then filled with strong cement
concrete and allowed to set; when set the two cylinders (which are supported)
are eased off or loosened as hereinafter described and the excavation for the shaft
commenced from the interior, when the concrete cylinder will sink as the earth is
removed.
In shaft sinking, the moulds are usually kept at the same level, and, when
the concrete cylinder has sunk to within a short distance of the bottom of the
mould, the mould is again filled and the process of sinking continued as before.
Additional vertical strength is given where required by the insertion of iron.
bars (suitably jointed) in the concrete by which means, should the concrete cylinder
become earth bound -towards the top and free at bottom there is no fear of its
being pulled asunder, these bars can also be used for the support of the concrete
lining when it is necessary from any cause to support it from top to bottom to
prevent it sinking further."
i
Should the concrete cylinder become earthbound or a large bed of rock (having
a large quantity of water resting thereon) be encountered, the iron curb
allowed to rest thereon and caulking proceeded with to keep back the water
The earth or rock is then excavated to form an egg shaped or domed chamber
so as to give room for the erection of a segmental mould of the same (or a
smaller) size as the first. The shaft can then be proceeded with as before at
the lower level. The chamber may be dispensed with if a smaller shaft be sunk
within the larger one.
The chamber should in all cases have a strong brick lining domed over at top
for making good to the shaft above.
Suitable shoes or wall boxes are inserted in the concrete whilst filling the
moulds or any fixings that may hereafter be required.
Chimney and other shafts are constructed in the reverse order viz.: by raising
the moulds as the work proceeds.
'
The moulds (preferably of iron) are truly cylindrical the external mould may be
in one or mere segments with a vertical joint or joints: on loosening the joints
the concrete is freed. In the case of mine shafts and well linings the moulds
may be slightly tapered so that the concrete eases itself as it sinks.
In the building of concrete chimney and other shafts they may be ornamented
by flutes, the flute moulds being arranged symmetrically round the interior of

page_text: the extermal mould and rigidly fixed thereto. If great heat has to be encountered
the internal mould is not used but fireclay flue tubes are inserted instead.
Hollows may be left in the concrete both for economy and lightness.
The interior mould is of iron and is sprung out by means of set screws on setting
it ready for filling. When filled and the concrete set, the mould springs in on easing
the set screws, thus freeing the concrete. In the case of a mine shaft or well
lining the internal mould may be slightly tapered so that the concrete eases itself
as it sinks.
With solid moulds (without joints) but having taper clearance the process can
go on continuously but in this case I prefer that the vertical bars should be
corrugated or grooved horizontally to afford good hold on the concrete and for the
purpose of fixing flat iron sole plates för the same purpose viz.: of pulling the
concrete through the mould free from disintegration.
In the construction of large and tall chimney shafts or columns 1 employ a
special multiple screw elevating gear & by suitable gearing 1 am enabled to turn
all the elevating screws at the same time, and at the same rate: the nuts of the
elevating screws being formed in the concrete, the screws being well greased so
that the concrete will not adhere to them. The necessary scaffolding is fixed to
the moulds either inside or out and rises with the moulds.
Dated this the Twelfth day of May 1894.
Improvements in Mine Shafts, Well Linings, Chimney and other
Shafts, and Apparatus for Constructing the same.
I WILLIAM SPIERS FREEMAN Invicta Works Otford Kent Civil and
Mechanical Engineer 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 :-
Mine shafts, well linings & chimney shafts have hitherto been chiefly constructed
of brickwork but in my invention I construct them of cement-concrete by means
of improved moulds as herein set forth, by which they are made monolithic and
impervious and of great strength and smoothness, (both within & without) so that
unlike brickwork they have in the case of mine shafts and well linings little
tendency to become earth bound in sinking.
In sinking a shaft by my method a strong cast iron curb or ring is laid upon
the ground & the mould (consisting of two cylinders) is fixed thereon; the annullar
space between the two cylinders is then filled with strong cement concrete &
allowed to set; when set, the two cylinders (which are supported) are eased off or
loosened as hereinafter described and the excavation for the shaft commenced from
the interior when the concrete cylinder will sink as the earth is removed.
In shaft sinking the moulds are usually kept at the same level, and when the
concrete cylinder has sunk to within a short distance of the bottom of the mould,
the mould is again filled and the process of sinking continued as before.
Additional vertical strength is given where required by the insertion of iron bars
(suitably jointed) in the concrete, by which means, should the concrete cylinder
become earth bound towards the top and free at bottom there is no fear of its
being pulled asunder, these bars can also be used for the support of the concrete
lining when it is necessary from any cause to support it from top to bottom to
prevent it sinking further.
Should the concrete cylinder become earthbound or a large bed of rock (having
a large quantity of water resting thereon) be encountered, the iron curb is allowed

page_text: to rest thereon and caulking proceeded with to keep back the water. The earth or
rock is then excavated to form an egg shaped or domed chamber so as to give room
for the erection of a segmental mould of the same (or a smaller) size as the first.
The shaft can then be proceeded with as before at the lower level. The chamber
may be dispensed with if a smaller shaft be sunk within the larger one.
The chamber should in all cases have a strong brick lining domed over at top
for making good to the shaft above.
Suitable shoes or wall boxes are inserted in the concrete whilst filling the moulds
for any fixings that may hereafter be required.
Chimney and other shafts are constructed in the reverse order viz.: by raising
the moulds as the work proceeds.
The moulds (preferably of iron) are truly cylindrical the external' mould may be
in one or more segments with a vertical joint or joints on loosening the joints the
concrete is freed. In the case of mine shafts and well linings the moulds may be
slightly tapered so that the concrete eases itself as it sinks.
In the building of concrete chimney and other shafts they may be ornamented
by flutes, the flute moulds being arranged symmetrically round the interior of the
external mould and rigidly fixed thereto. If great heat has to be encountered
the internal mould is not used but fireclay flue tubes are inserted instead. Hollows
may be left in the concrete both for economy and lightness.
The interior mould is of iron and is sprung out by means of set screws on setting
it ready for filling. When filled and the concrete set, the mould springs in on
easing the set screws, thus freeing the concrete. In the case of a mine shaft or
well lining the internal mould may be slightly tapered so that the concrete eases
itself as it sinks.
With solid moulds (without joints) but having taper clearance the process can
go on continuously but in this case I prefer that the vertical bars should be corru-
gated or grooved horizontally to afford good hold on the concrete and for the
purpose of fixing flat iron sole plates for the same purpose viz. of pulling the
concrete through the mould free from disintegration.
In the construction of large and tall chimney shafts or columns I employ a
special multiple screw elevating gear and by suitable gearing I am enabled to turn
all the elevating screws at the same time, and at the same rate: the nuts of the
elevating screws being formed in the concrete the screws being well greased so
that the concrete will not adhere to them. The necessary scaffolding is fixed
to the moulds either inside or out and rises with the moulds.
The principal features of my invention will be made more clear by reference to
the accompanying drawing.
Fig. 1 represents the mode of constructing and using the mould for well sinking
linings.
W. represents the well just started to be sunk.
1. C. represents the iron curb for supporting the weight of the concrete lining
and for cutting its way down as the earth is excavated from the interior.
C. represents the finished lining which has sunk through the mould M¹ M" the
annular space between MM" is slightly wider at bottom than at the top to give
clearance to the lining as it sinks.
S. S. are the mould supports.
H. H are the hangers to support the internal mould M" & having distance
pieces or guides D thereon to keep moulds parallel.
These moulds may have easing joints similar to that shewn at C. J. Fig. 2 on M¹
and similar to that shewn at J Fig. 3 on M" if desired, but rapping the moulds
when the concrete is partially set is usually sufficient, the sliding of the lining
through the moulds producing a hard & smooth surface.
Fig. 2 represents the mode of using a mould for constructing a monolithic lining
to a well already dug H. H. being the hanger arms B. B. the bosses to ditto Sp
the spindle passing through the axis and having an eye at the end to which a wire
rope W. R. or chain is attached drawn up by windlass Wn by wheel Wh fixed on

page_text: gantry G. thus the mould is always kept true & plumb. This mould also has
slight clearance to enable it to be drawn up easily when rapped and also a
contracting joint or joints as shewn at C. J. to be used if necessary.
Should it be necessary to proceed with the lining very rapidly then I prefer to
use superimposed wood moulds from top to bottom filling round same with concrete
as each mould is added on the top of the last. These wood moulds are made by
nailing slats on wooden rings such rings having a contracting joint formed by
inserting a V shaped segment therein which is withdrawn when it is desired to take
out the moulds.
Fig. 3 represents the mode of using a mould for constructing chimney and other
shafts in concrete with or without ornamental flutes or grooves therein. The mould
shown consists of a cylinder with easing joints J. On the interior of the cylinder
are rivetted half round fluting moulds F. M. as shewn, the cylinder and the fluting
moulds having the necessary clearance to draw up easily. The mould is elevated
by means of the elevating screws Sc which are embedded in the concrete as before
described, or in case extra rapid building is required screw thrust nuts in halves
are fixed round the screws and take an extra bearing in the concrete. Each
elevating screw is attached to a pinion P gearing into a spur wheel or ring S. W.
and thrusting against the boss on the hanger H so that on turning any or all of the
pinions by means of the capstan heads Cp all must turn at the same time, thus
raising the mould truly and in a perpendicular line if the same has been truly set
to start with. The spur wheel boss S. W. B. is of sufficient internal diameter to
allow of fire clay flue tubes or a core to be inserted as shewn at F. T. round which
the concrete is placed.
The filling of the mould is facilitated by having a platform or gallery Pf round
the mould and rising therewith with protecting handrail Hr and ballusters Bl.
Pi represents the pitch of the elevating gearing. Instead of the spur wheel the
whole of the screw pinions may be joined and be made to revolve simultaneously
by means of a chain passing round the same.
Having thus described the nature of my invention and the manner of performing
the same I claim-
Firstly. In forming a well or shaft lining as the sinking proceeds. The use of
two parallel circular moulds forming an annular space into which concrete is placed
and allowed to slide through by its own weight as the earth, soil or material is
excavated from under the same substantially as set forth and described.
Secondly. In forming well linings, chimney & other shafts. The use of irou
rods or bars embedded in the said lining to give longitudinal strength substantially
as set forth.
Thirdly. In forming well or shaft linings. The use of a single internal mould
to be raised (as the concrete lining is formed) by means of a central chain rope or
screw substantially as shewn and described.
Fourthly. In forming well or shaft linings. The use of superimposed wooden
moulds with or without a V jointed segmental contracting joint for removing
same.
The use of a sliding mould to
The use of flute moulds (fixed
Fifthly. In forming chimney and other shafts.
be raised as the concrete is filled in & set.
Sixthly. In forming chimney and other shafts.
or unfixed) arranged symetrically round the above mould.
Seventhly. In forming chimney and other shafts. The use of elevating screws
embedded in the concrete for the purpose of raising the mould substantially as
described.
Eighthly. In forming chimney and other shafts. The use of pinions on the
elevating screws geared into a spurwheel common to, all for the purpose of turning
all simultaneously.
Ninethly. The use of a gear chain in lieu of the beforementioned spur wheel
for the purpose of revolving all screws simultaneously.

page_text: Tenthly. In constructing a chimney or other shaft in concrete. The use of a
platform or gallery attached to the mould.
In witness whereof I have hereunto set my hand this the Fourteenth day of
WM. S. FREEMAN.