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A SHORT HISTORY OF RESIDENTIAL WATER METERS
PART I MECHANICAL WATER METERS WITH MOVING PARTS
Installations for Buildings and Ambiental Comfort Conference XXI- edition
Timisoara - ROMANIA 18-20April 2012, pp. 27-35
By, Dr. Phys. Monica Sabina Crainic,
S.C. AEM S.A., Research Department,
26 Calea Buziaşului 300693 Timişoara, Romania Tel: 40-256-222200, Fax: 40-256-490928,
E-mail: sales@aem.ro, or monicasabinacrainic@yahoo.com
Abstract
Water is one of our most important natural resources. We drink it, use it for cooking and cleaning, and depend
on it in many aspects of our lives. For this motive she must be protected and managed economically. It should
not be surprising, then, that we have a need to measure the amount of water we use. In this paper we present a
short history of mechanical residential water meters with moving parts such as displacement and velocity water
meters.
Key words: water meters, public utilities, history of technology
Introduction
Water meters - a device used to measure the volume of water usage - are used at each
residential and commercial building in a public water supply system.
Figure 1 show types of water meter which are classified by the flow metering
techniques commonly in current use. In a mechanical water meter the meter has a moving part
to measure flow and for the non-mechanical water meter there are no moving parts.
Fig. 1 Type of residential water meters
For mechanical water meters there are two major methods of flow measurement in
use, displacement and velocity, with sub-technologies within each of them. Common
displacement designs include oscillating piston and nutating disk meters. Velocity-based
designs include jet meters and turbine meters.
Displacement water meters
A positive displacement water meters, or PD meter, measures the volume flow rate of
a continuous flow stream by momentarily entrapping a segment of the fluid into a chamber of
known volume and releasing that fluid back into the flow stream on the discharge side of the
meter. By monitoring the number of entrapments for a known period of time or number of
entrapments per unit time, the total volume of flow or the flow rate of the stream can be
ascertained. The total volume and the flow rate can then be displayed locally or transmitted to
a remote monitoring station.
Common displacement designs include oscillating piston and nutating disk meters.
a). Oscillating piston meters
Although patents for liquid meters were issued earlier, it is believed that the first water
meter was proposed in 1850, by William Sewell of Williamsburg, New York, USA, and the
first meter actually produced (see fig. 1) is claimed to be made by Henry R. Worthington of
New York [1-2].
Fig 2 Original duplex-piston meter [1-2] Fig. 3 Thomas Kennedy water meters
The early meters were of reciprocating piston design, after the familiar D-slide valve
used in steam engines. Worthington’s original meter consisted of two cylinders and plungers
with inlet and outlet ports arranged in such a way that as water is in one cylinder was
discharged by the piston, the other cylinder was filling. Water flow through these meters was
subject to pulsation cause by the action of the piston, and high friction losses were
encountered. Close accuracy was impossible, because the meter counted the number of piston
strokes, whose length varied with the flow rate. Variations in velocity of the strokes caused
variable compression of the rubber cushions at each end of the cylinders.
In 1824 by Thomas Kennedy from Argyle shire United Kingdom, with the help of
local, Kilmarnock, clockmaker, John Cameron made a single-piston, double-acting water
meter (see fig.3). Water coming into the meter is directed by a small valve either above or
below a piston in a cylinder of known volume. The rise and fall of the piston, apart from
expelling the measured quantities of water, also drives a counting mechanism and recording
dials.
The Worthington water meters was widely known in the United States and Kennedy
water meters was one of most perfect of the meters used in England.
Between 1870 and 1910 more than 400 patents were issued on liquid meters. Many of
these patents describe constructions that were hopelessly impractical and complicated [3-8].
One of these patents [2] issued to J.P. Lindsay in 1871, described an oscillating disc meter,
which today would be called a reciprocating meter with a single piston. This meter was round
and flat in shape and controlled by a reversing valve. Most of these early designs had
impractical features, such as the use of moving valves; the need for some parts to start and
stop during each cycle of measurement; the use of floats, of back-and-forth oscillating motion
of the pistons, and of the inner face of the housing as the measuring chamber; the inlet and
outlet not on a common axis centered in the meter; inadequate capacity resulting in excessive
pressure loss; and apparently no consideration for manufacturing costs.
These meters, although purporting to be displacement meters, were only semipositive.
The high friction load and complex moving parts must have permitted much slippage, thus
impairing low-flow accuracy. Present displacement meters have capillary seals rather than
packing seals to prevent slippage, but, in any event, the excellences of manufacture reduce
slippage to a negligible factor.
In 1884, the first practical oscillating-piston meter was issued to Lewis H. Nash. He
stated in his patent [9-10] that this meter was an adaptation of an existing steam engine, but
the piston shape and movement are similar to the oscillating-piston meters of today. It was a
simple, workable measuring unit.
b). Nutating disc meters
In the 1820s the mill owners Edward & James Dakeyne of Darley Dale, Derbyshire
designed and had constructed a hydraulic engine (a water engine) known as "The Romping
Lion" to make use of the high-pressure water available near their mill [11-12]. Little is known
of their engine other than from the somewhat unclear description accompanying the patent,
which was granted in 1830.
The first people to develop steam-powered disc engines based on the Dakeynes' design
were George Davies and Henry Taylor who patented their engine in 1836. It was fitted with
valves to control the admission of steam and also differed from the Dakeynes' version in that
the axis of the engine was horizontal and the casing of the engine rotated around the disc, the
opposite of the original. More patents followed over the next eight years, mainly introducing
expansive working and improving the engine's sealing.
A competitor to Davies and Taylor was former locomotive engineer George Daniell
Bishopp, who builds his first engine in 1840, and a patent was granted in 1845.s However, it
was not an efficient prime mover because of the lack of sufficiently tight packing around the
edge of the disc portion of the piston; thus it fell into disuse.
A nutating-piston liquid pump, using what today would be called a conical disc was
patented in United States in 1854 by Stephen D Carpenter [13]. A modification, also for use
as a pump, was patented by Charles H. Hersey in 1868 [14]
The date of the first nutating-piston or disc meter is not clear. Limited patents on this
type were issued in 1887 and 1888, and patent issued in 1892 to James A. Tilden [15],
covered features of a flat-disc meter. In the same year, two companies that are still in the
meter business today NIAGARA METERS and HERSEY METERS from USA were
organized, one to manufacture conical-disc meters and the other flat-disc meters.
These manufacturers had problems with hard rubber discs breaking at fast flows. One
solution, developed by John Thomson [16], was for a thrust roller to control the
circumferential thrust of the disc in its movement and thus prevent jamming of the disc
against the diaphragm at the slot. This method continues to be widely used.
Another approach was to mold a metal reinforcement into the hard rubber disc section
of the nutating piston. The diaphragm was then used as a thrust plate to prevent rotation. In all
these designs, the disc section (whiter flat or conical) was made as thin as possible to reduce
weight; however, this necessitated a very close fit between the edge of the disc and the
chamber wall to minimize slippage. In 1892, George B. Bassett [17] designed and began
manufacturing 15 mm conical-disc meters with the disc section 6 mm thick, instead of 2 mm
or less. He found the added weight to be no apparent disadvantage, but the greater thickness
gave a more capillary seal against a slippage for a given clearance. A reinforcing plate was
later added.
Velocity water meters
A velocity-type meter measures the velocity of flow through a meter of a known
internal capacity. The speed of the flow can then be converted into volume of flow for usage.
There are several types of meters that measure water flow velocity to determine totality usage.
They include among others turbine and jet meters (multi-jet). Most velocity-based meters
have an adjustment vane for calibration of the meter to required accuracy
a). Turbine meters
Turbine meters have been around for many years. In fact, the generally accepted view
places the invention of the first turbine meter in 1790, when Benjamin G Hoffman, in
Hamburg, Germany, published a booklet describing a form of current meter, invented by
Reinhard Woltman, for measuring flowing air and water [1, 18]. This device seems to be the
first practical meter for the purpose; it has since changed materially in design and
construction.
In general, the meter (see fig. 4) consisted of a very light waterwheel operated by the
current and carrying on its axis a worm for actuating gearing and a totalizer. The rate of flow
was computed from the rotations during a given period.
In 1878 it was not generally accepted that the meter could be used in a closed pipe.
The first water meter was a reaction turbine counter with a cast-iron housing lined with
bronze and other nonferrous metals [1-2]. This water meter was apparently designed in 1850
by Mr. Werner von Siemens working with Mr. Adams in Germany. It will be seen from the
fig. 5 that the water entered the measuring chamber through angularly position inlets, causing
the flow to impinge on one side of the vanes of the rotor at a 90 angle. To prevent the rotor
from spinning too fast, other, much smaller inlets entered in the chamber at an opposite angle,
creating a small force in the other direction
Fig. 4 Original form of the Woltman meter
(a) (b)
Fig 5 Siemens water meters (a) English, (b) German [1]
The two Siemens meters, English Siemens manufactured by Guest & Chrimes of
Rotherham, England (now Siemens from United Kingdom) which somewhat resembled a
centrifugal pump reversed, using a drum reaction wheel controlled by regulating vanes and
the German Siemens manufactured by Siemens & Halske of Berlin (now Diehle Metering
from Ansbach) which was an early form of rotary-vane meter are probably the most
extensively employed in Europe.
This meter was substantially different from the conventional turbine meter in which
the water strikes the blades of a rotor at approximately 45.
Whereas the Woltman meter (see fig. 6 a) had a horizontal axis that permitted a
straight through flow, the current or turbine meters developed in the United States since 1890
and until 1960s, (see fig. 6 b) usually had a vertical rotor spindle. This design facilitated a
vertical drive to the register, but necessitated changes in flow direction within the meter to
keep the inlet and outlet in a straight line.
Fig. 6 Woltman meters (a) parallel (b) perpendicular to the axis of the pipeline
With the advent of magnetic drives, some models have returned to horizontal rotor
spindle, which gives lower pressure loss.
b). Multi-jet Meters
Multi-jet meters use multiple ports surrounding an internal chamber, to create multiple
jets of water against an impeller. The impeller rotation speed is in relation to the velocity of
water flow.
Multi-jet meters were first designed and produced in Germany beginning with
Siemens-Halske in 1867. At least one United States meter manufacturer marketed a multi-jet
meter in late 1920s and into the 1930s for export, primarily to Latin American countries. They
have been available to United States water industry since the early 1960s [2].
Multi-jet meters are manufactured in two basic designs, which are classified as wet
register model where the impeller shaft is connected directly with the counter and dry register
model where only the turbine functions in the wet chamber. The introduction of magnetic
drives for meters has made the dry register more prevalent.
References
[1] Ross E. Browne „Water Meters” Van Nostrand’s Engineering Magazine, vol XXXIII,
July-December 1885, p. 1
[2] *** “History of Water Measurement and Development of Water Meters” in Manual of
Water Supply Practices M6 American Water Works Association 1999
[3] James Reginald William “Improvements in Water Meters and the like” GB Patent No.
10435 from 6 May 1898
[4] Dubuison Gustave “Water Meters and the like” Belgium Patent No. 16328 from 7 Oct.
189
[5] Duncan William “Improvements in Water Meters” GB Patent No. 2288 from 31 Mar 1900
[6] Wilhelm Germultz “Water Meters” GB Patent No. 9285 from 4 Aug 1900
[7] Sharp John “Improvement in and relating fluid meters, motors and pump” GB patent No.
20058 from 7 Sept. 1905
[8] Kelley John “Water Meter Piston” US Patent No. 950636 from 1 Mar 1910
[9] Lewis H. Nash “Rotary Water Meter” US Patent No. 280220 from 26 June 1883
[10] Lewis H. Nash “Water Meter” US Patent No. 280221 from 26 June 1883
[11] *** “The History of the County of Derby” The Materials collected by the Publisher
Stephen Glover, Edited by Thomas Noble, Esq, London, Henry Mozley and Sons Publisher
1829, pp 354, 363
[12] Bryan Bunch, Alexander Hellemans “The History of the Science and Technology : A
Browser's Guide to the Great Discoveries, Inventions, and the People Who MadeThem from
the Dawn of Time to Today” Houghton Miffin Company Boston New York 2004
[13] Stephen D Carpenter „Rotary pump” US Patent No 11776 from 10 Oct. 1854
[14] Charles H. Hersey “Improvement in rotary pumps” US Patent No. 82833 from 6 Oct.
1868
[15] James A. Tilden “Disk water meters” US Patent No. 486992 from 29 Nov 1892
[16] John Thomson „Disk water meter” US Patent No 476102 from 31 May 1892
[170] George B. Bassett „Disk water meter” US Patent No. 501203 from 11 July 1893
[18] Arthur H. Crazier „Water Current Meters in the Smithsonian Collections of the National
Museum of History and Technology” Smithsonian Institution Press City of Washington 1974