Flow meter Avery Hardoll BM Series BULKMETERS
- Positive displacement liquid measuring instruments
- Unequalled performance in measurement
- Free from installation effects
Flow Rates of 25 gall/min (115 lit/min) to 850 gall/min (3870 lit/min)
BM SERIES METERS
Avery-Hardoll bulkmeters are precision made, positive displacement, liquid measuring instruments,which maintain accurate metering over long periods of operation. Simplicity of design and construction together with sustained accuracy has led to the widespread use of these meters on aviation refuelling vehicles, in oil terminals throughout the world and also as master meters for use in calibration.
The positive displacement principle is the ONLY accurate method of measuring fluid flow. No other technology can achieve such accuracy because measurement becomes inferred, that is indirect and subject to assumption.The Avery-Hardoll bulkmeter directly converts volume to rotational output with minimum scope for error and with minimal disturbance from surrounding conditions, eg. turbulence from nearby valves, bends, etc.
The product enters the meter through the inlet manifold (1) and causes the rotor (4) to revolve by pressure on the vanes (3).
The proximity of the rotor (4) to the body (2) forms an efficient seal, whilst the profile of the casing ensures that the vanes (3) are guided through the measuring crescent (5), where the volume of product is accurately measured.
Product at line pressure fills the spaces between the inner (6) and outer (7) end covers providing `pressure balanced inner end covers’ which are therefore protected from distortion due to changes in line pressure.
An extension shaft driving through a pressure tight gland in the meter front cover, transmits the rotor revolutions to the calibrating gearing (8) which drives the counter (9).
MANIFOLD : Fabricated steel or ductile iron (ductile iron not available ontriple capsule meters)
BODY : Ni-Resist cast iron
VANES : Carbon
ROTOR : Aluminium or Ni-Resist cast iron
OUTER COVERS : Aluminium or Ni-Resist cast iron
INNER COVERS : Ni-Resist cast iron
BEARINGS : Stainless steel
SEALS : High nitrile or fluorocarbon
Maximum working pressure : 10.5 bar (150 psi)
Test pressure : 21 bar (300 psi)
Temperature range : -28ºC to 100ºC
Volume per revolution : 2.27 litres (single capsule)
4.54 litres (double capsule)
6.82 litres (triple capsule)
Repeatability typically : 02%
Typical accuracy curves for basic meter build (10:1 turndown)
Calibration adjustment is provided to minimize the meter error at any selected flowrate. Adjustment is stepless; no gear changing is necessary; and the calibration screw is easily accessible after breaking a seal and removing a sealing screw.
All meters are tested to 300 psi (21 bar).
All Avery-Hardoll meters are tested before despatch at a range of flowrates and test certificates can be supplied if requested.
The fluid used for testing is odorless kerosene.
Specific gravity at 60/60ºF, 15/15ºC = 0.8 Viscosity at 60ºF, 15ºC = 2.4 centistokes.
Suggested correction to be made to the calibrating mechanism when used with products with different viscosities as follows:
|Gasoline||+ 0.1%||+||means increase counter readings|
|Kerosene||–||0.0%||–||means decrease counter readings.|
BM series meters Flow range
The low pressure drop for the BM series of Avery-Hardoll bulkmeters is shown opposite.
Avery-Hardoll bulkmeters can be used on all petroleum products of all viscosities that are normally pumped. However there is obviously an increase in pressure drop with more viscous fuels which will, under normal circumstances, limit the maximum flowrate obtainable.
It is recommended that the pressure drop through a bulkmeter should not exceed 15 psi (one bar), above which the load on the bearings will start to cause wear. Consequently when using products with viscosities (at operating conditions) above 100 centistokes, it is necessary to reduce the maximum permitted flowrate. As a guide it is suggested that the pressure drop through the meter should not exceed 10 psi (0.7 bar) for continuous running at maximum speed or 15 psi (one bar) for continuous running at half speed.
A full range of accessories is available for use with all Avery-Hardoll bulkmeters and these are described in the following paragraphs. Details may be obtained from each relevant leaflet.
The meters are fitted with standard Veeder-Root counters, having a five large figure zeroising drum and a seven figure small non-zeroising totaliser and can be supplied to read in any of the following units:
|Imperial gallons||US gallons||Cubic metres|
MECHANICAL PRESET AND PRESET VALVE
A Veeder-Root preset register with five figure resettable counter is used to preset a batch to be delivered. This controls a lever operated preset valve via a mechanical linkage, providing two stage closure and precise shut off of flow.
MECHANICAL PRESET WITH MICROSWITCHES
Microswitches can be fitted to the preset register to control pump start and stop, and solenoid operated preset valves.