VAF Instruments - Positive Displacement Flowmeters, Oil Meters, Biofuels Metering

VAF Instruments are one of Europe’s leading manufacturers of positive displacement flowmeters with over 65 years experience and expertise in flowmeter manufacture and design.  Quality and reliability form the cornerstone of VAF’s world-wide reputation as a market leader in high accuracy flow measurement equipment.  The VAF sliding vane flowmeter incorporates a simple yet rugged patented design which offers unparalleled
performance and exceptional reliability – When you purchase a VAF flowmeter you are Investing in a true Dutch masterpiece.

Principle of operation

VAF Instruments positive displacement flowmeters operate on the sliding vane principle. The meter consists of a specially shaped housing in which a rotor can rotate freely. Two pairs of vanes are placed into four slots in the rotor. Each pair is held in position by a rod and can move in and out of the rotor freely.  The radial movement of the vanes is guided by the special inner shape of the housing. This patented construction provides a constant seal between the inlet and the outlet of the meter. The incoming liquid forces the rotor to rotate and the rotation of the rotor is transferred via a magnetic coupling to a readout device such as a mechanical or electronic counter  or a pulse transmitter for remote readout, flow data processing or connection to a process computer (EMS)..

To accurately measure extreme low flows of liquids the “Milliflow” uses the dependable four-piston positive displacement technique.  Miniature precision machined 316 stainless steel pistons running inside carbon cylinders enable flow rates as low as 1.0 l/hr to be accurately measured.  Pressure rating is 25 bar as standard with options up to 200 bar.  All wetted parts are manufactured from stainless steel, FTFE and carbon which make the flowmeter compatible with most clean liquids.  The Milliflow can be fitted with a six digit mechanical totaliser with or without pulse transmitter, pulse transmitter only or electronic Flowcount which provides digital flow rate / total readout with an optional 4-20mA output.  Both the NAMUR pulse transmitter and the electronic Flowcount are ATEX Certified for installation within Hazardous Areas.

VAF have employed highly accurate machining technology to manufacture their patented sliding vane flowmeters in 10mm and 15mm bore sizes providing an extremely accurate means of measuring low liquid flows.  LoFlow Vane meters will measure a wide variety of liquids from low density LPG through to highly viscous resins.  Models are available in carbon steel and stainless steel, with pressure ratings up to 200 bar.  LoFlow meters can be fitted with a six digit mechanical totaliser with or without pulse transmitter, pulse transmitter only or electronic Flowcount which provides digital flow rate / total readout with an optional 4-20mA output.  Both the NAMUR pulse transmitter and the electronic Flowcount are ATEX Certified for installation within Hazardous Areas.

The ProFlow Series is the latest addition to the VAF sliding vane positive displacement flowmeter range and was specifically developed for the measurement of all kinds of hydrocarbon liquids, in particular diesel, medium & heavy fuel oils for combustion engines, lubricating oils and many other oil-like liquids.  Available from 15mm to 50mm bore sizes with flanged PN16 or ANSI 150 ends to handle flow rates from 2.5 l/min to 500 l/min.  ProFlow meters can be fitted with a six digit mechanical totaliser with or without pulse transmitter, pulse transmitter only or electronic Flowcount which provides digital flow rate / total readout with an optional 4-20mA output.  Both the NAMUR pulse transmitter and the electronic Flowcount are ATEX Certified for installation within Hazardous Areas.

Applications

• Dye and additive injection to fuel and petroleum spirit
• Ammonia and caustic addition to adjust Ph during chemical reactions
• Calibration of metering pumps
• Dosing perfumes for soaps and proprietries
• Applying size to paper

Applications

• Injection of resin and catalyst into plastics moulding machines
• Metering oil in high pressure hydraulic systems
• Addition of fats and vegetable oils to food and animal feed
• Continuous dosing of additives into petroleum spirit and fuel oil

Applications

• Fuel consumption measurement
• Oil injection
• Measurement of fluid movement in hydraulic systems
• Accurate measurement of viscous fluids at low flow rates

MidFlow sliding vane flowmeters are used in continuous metering applications, in-line blending processes and batch control applications.  They have a simple, rugged design and with only a few almost frictionless moving internal parts there is hardly any internal wear.  This feature helps to provide a long service life.  MidFlow meters have no mechanical seals saving you from regular maintenance and possible leakage of process liquids into the environment. The flowmeter is driven by the process liquid which makes it suitable for locations without power supply.  The high accuracy of the flowmeter (down to 0.1% and repeatability
0.05%) is not influenced by process pressure, temperature,
mechanical pipe strain or liquid turbulence and therefore straight
inlet and outlet pipe diameters are not required.

HiFlow sliding vane flowmeters are manufactured in ductile iron and stainless steel and available from 150mm to 300mm bore sizes to handle flow rates up to 16000 l/min.  They offer exceptional accuracy and repeatability, with a low pressure drop.  The simple, rugged design provides a long service life.  All industry standard Veeder-Root registers and ticket printers can be fitted to the HiFlow making it a very versatile meter, and a true work horse.  The flowmeter is driven by the process liquid which makes it suitable for locations without power supply.  The high accuracy of the flowmeter (down to 0.1% and repeatability 0.05%) is not influenced by process pressure, temperature, mechanical pipe strain or liquid turbulence and therefore straight inlet and outlet pipe diameters are not required.

VAF was founded in 1938 in Dordrecht, Holland.  Initially the company manufactured electric petrol pumps but as a result of fuel shortages in the 1940's the demand for petrol pumps dropped sharply.  However there continued to be a demand for precision measuring instruments, and after WWII the company decided to specialise in this field.  In the 1950's the range of measuring instruments offered by VAF was extended considerably and the company's main target became the processing industry followed later by the maritime industry.  In the early 60s VAF decided to respond to the demand for dosing systems and actively sought a supplier of shut-off valves.  A link was established between VAF and Conoflow, an American company specialising in control valves and in 1963 it was decided to join forces.  In 1966 the company in turn was taken over by the ITT Corporation. This take-over enabled VAF to become known internationally and the company was the first to develop a viscosity meter for the shipping industry which was marketed under the name viscotherm.  To this day viscotherm continues to be a watchword on the majority of seagoing vessels all over the world.  In the 1980's ITT decided to concentrate solely on telecommunications and VAF saw this as an opportunity to go its own way.  In 1988 the company was taken over by its present owners and since then it has continued as an independent enterprise specialising in the manufacture of fluid measuring and control instruments and supplying customers all over the world.

Applications

• Batching solvents, varnishes and oils into mixing vessels
• Blending high temperature bitumen products
• Metering flows of fuel oil and lubricating oil to large diesel engines
• Injecting high viscosity resins into plastic moulding machines

Applications

• Loading / unloading of road and rail tankers
• Ship refuelling
• Measurement of large fuel flows in power stations
• Accurate measurement of viscous fluids at low flow rates
• Blending of additives in the process industry
  
  

Calibration and Service

All VAF flowmeters undergo a rigorous quality control procedure prior to despatch.  Calibration is carried out on a state of the art computer controller calibration rig, traceable to European Weights & Measures Standards, to ensure each flowmeter conforms to, or exceeds, its published specification.  

Each VAF flowmeter leaves the factory accompanied by its own unique calibration certificate.  This is your personal guarantee that your new investment has been manufactured and tested to the highest standards.

VAF have appointed Flowquip as an official sales and service agent and their relationship with VAF flowmeters goes back more than 20 years.  A vast amount of technical expertise in the form of product and application knowledge has been accumulated over this time and heavy investment in terms of personnel and equipment undertaken.

Flowquip hold a comprehensive stock of VAF flowmeter spares and can also provide function testing and full traceable calibration via their own in-house calibration rig.

Certification and Approvals

VAF flowmeters comply with all the latest European legislation – including ATEX and the Pressure Equipment Directive.  VAF has a dedicated full-time Quality Department whose sole task is to ensure that VAF flowmeters achieve the highest possible quality standards.