Archive | 2015

We want your opinions

Survey 1We recently launched two new annual opinion surveys – building on a number of surveys that we have conducted in the past –to examine industry trends.

The new surveys look at the challenges facing manufacturing and production, regulation, safety, international standards and general trends. One lucky respondent will win a Kindle for taking part.

One survey is specifically for oil and gas, the other is for the general process sector.

Meeting the requirements of safety standards including safety integrity levels (SIL), pressure equipment directive (PED), positive material identification (PMI), ISO17025 and the control of major accident hazards (COMAH) can help to avoid the potential failure of a critical component which could lead, in the worst case, to a catastrophic failure of a process and loss of life.

There has been increased focus on safety issues in the offshore and process sectors over recent years. We want to make sure that our manufacturing focus is on safety in relation to both the environment and industry trends.

Issues surrounding the environment and hydrocarbon releases, asset aging and life extension drive the focus on safety. We want to be able to help in the process of recognising hazards and reducing risk as well as help engineers to take ownership of risk and asset integrity through proving assertions about the functionality and construction of instruments.

Asset integrity management ensures that the people, systems, processes and resources that deliver integrity are in place, in use and will perform on demand over the asset’s lifecycle.

Being able to prove assertions about the manufacture and functionality of equipment are vital in this process.

That’s why we are seeking the views of design engineers, industry leaders and decision makers across industry.

To take our survey – and perhaps you could win a Kindle – visit or and spend just a few minutes answering the questions.

The versatile VFF

Litre Meter was founded 40 years ago as a manufacturer of industrial flowmeters. Today, the company still manufactures flowmeters, but with a slight shift in focus – more than 80% of its products are designed specifically for the harsh conditions of the offshore oil and gas industry.

The shift towards offshore supplying happened largely due to Litre Meter’s ability to engineer new products, as many offshore oil and gas rigs require custom-built flow measurement solutions for chemical injection; however, the ability to engineer new products has sometimes been a setback for Litre Meter, as the majority of orders would often require custom engineering despite the company’s extensive catalogue of standard products.

Litre Meter defines its company by the strapline, ‘Specialist flow measurement engineering’, representing four of its unique and client-oriented company principles:

  • Specialist: Litre Meter is a specialist manufacturing company, focusing solely on products for measuring flow, rather than level or pressure.
  • Flow: its products drill down into the finer flow details, such as flow rate and flow total.
  • Measurement: its products measure flow accurately – they are not flow switches or flow indicators.
  • Engineering: although it offers a catalogue of standard products, Litre Meter can engineer bespoke solutions for unique challenges.

The VFF series

Litre Meter’s shift in focus began a little over 25 years ago, when it first adapted a standard industrial flowmeter for use on a North Sea oil rig. The popularity and success of this custom device led to the eventual production of their flagship range: the Viscous Fluids Flowmeter (VFF) series.

The VFF series is hugely popular and very adaptable, but its standard range has still been largely overshadowed by a flood of custom orders – until recently. One of the innovations for the 2015 range of VFFs included a new by-product: the FlowPod. The device itself is two-wire and fully HART compatible, with stainless steel housing. It opens up the popular VFF series to an even wider range of low-flow applications, and gives even the most obscure requirements near-instant access to Litre Meter’s innovative engineering without the need for custom designs.

Introducing the FlowPod

Flow Pod direct mount

The FlowPod mounts directly on the VFF flow meter.

Litre Meter decided quite early on that the FlowPod would be its only supporting instrument, and it has completely transformed the way the VFF range can be used.

Designed as Exi and Exd from the outset, the FlowPod was built in an enclosure small enough to be mounted directly onto the meter body, and gives Litre Meter an innovative method of incorporating extra functionality like reverse flow and redundancy measurement.
For Litre Meter, introducing the FlowPod to the VFF range was a great way to combine multiple design elements, gathered over 30 years of experience, to make an impressive and useful meter with a focus on utility plus weight and size reduction.
The 2015 VFF range includes more than 800 end-user drawings, representing more than 115,000 meter combinations and covering almost every conceivable possibility. While previously, around 80% of Litre Meter’s sales were for custom products, the introduction of the FlowPod means that only 5–10% of meters will now need any extra engineering at all. Most customers can simply access instant PDFs of general arrangement drawings, parts-list drawings and lifting diagrams, together with STEP files, as part of their Litre Meter quotation.
For Litre Meter, this means a faster sales cycle and more revenue; for the customer, it means much faster quotation, production and manufacturing times. 2015 has already been a big year for Litre Meter, and by raising its game and producing a range of meters without equals, it has truly cemented itself as a top-tier supplier of flowmeter technology to the chemical injection industry.

First published in Gas Technology Review



IMG_9572 LF03 white bgWe recently re-designed our popular VFF (Viscous Fluid Flowmeter) range of positive displacement flowmeters. The innovations in VFF technology make it ideal for bespoke flow measurement.

Innovations include a new compact size and design with reduced weight using high strength material specifications for high pressure applications. The new range of meters is suitable for low and high viscosity liquids at pressure ratings from 414 bar right up to 4,000 bar (60,000 psi). The range covers the measurement of fluids from 0.3 centistokes (cSt) to 100,000 cSt and flow rates of 0.0008 l/hr to 16,200 l/hr.

We have 40 years’ experience in successfully designing and manufacturing bespoke flowmeters for extreme environments for the most demanding industries and applications.

The VFF series has been distilled into one series to meet the specific requirements of chemical injection flowmetering. The new 2015 VFF range uses the same ultra-reliable rotary/oscillating piston technology that Litre Meter has developed and refined over the past 30 years. With one moving part the flow meter is a robust and low maintenance component within a chemical injection system.

The VFF range has a wide of standard options so we can quickly respond to fulfill most chemical injection enquiries. A full drawing package is available detailing every option in either PDF or STEP formats.

Specifying the right meter for a system is now even easier to specify with a new VFF meter software, a step-by-step builder that takes the user through all the meter options available. When the meter has been selected the user can search the Litre Meter database of over 400 general arrangements and parts listing drawings. For more details the user can browse 3D STEP files for the correct meter to download and insert into the skid assembly.

Meters are constructed from 316L stainless steel, Duplex Super Duplex, titanium and 6Mo. Other materials are available on request. Standard connections include NPT, Autoclave, ANSI flanges, Grayloc hubs, Galperti hubs and Techlok hubs. Two wire Exia and 2/4 wire Exd versions are available and 4-20mA, HART7 communications is standard with new pickup sensor capabilities.

Other innovations in the 2015 VFF range include a new rotatable and positionable Exd approved display union, new sensing options with increased reliability, reverse flow detection and increased resolution.

We are excited about the new range. The new compact and lightweight design has been developed specifically for integration within chemical injection skids. Its footprint is further reduced because positive displacement flowmeters don’t require straight lengths of pipe in the system before or after the meter.

We have also responded to industry demands with regard to lifting requirements for offshore by adding lifting eyes manufactured from certified forged material to every meter that weighs 16 kg or more.

New reed sensors now available

IMG_9574 sensor white bgWe have launched new sensor solutions to complement our revamped range of VFF flowmeters.

Our reed sensor package has been improved and now comes in a 316 stainless steel enclosure which is easy to install within the VFF range. The sensor comes complete with two reed switches that can be set for reverse flow detection or redundancy.

The sensor is tested to one billion pulses and environmentally tested in accordance with BS EN 13628-6: 2006. It is temperature rated to -20 to +80°C and it is available with the two or four wire Flowpod – the new explosion proof flow indication display unit for Litre Meter positive displacement flowmeters.

The non-wetted part has an M6 connector and the sensor is compact and designed for use at high pressures.

The new optional field sensor package comes in the same robust 316 stainless steel housing in order to make the sensors interchangeable with one another. The field sensor enables the output resolution of the VFF meter to be increased by a factor of twelve and it can still detect reverse flow.

Litre Meter strengthens South Asia team

LM1 - Claus Weihermueller(1)As part of part of the TASI group of companies Litre Meter now has new representation in Singapore. A new KEM/TASI Flow office in Singapore has been established with Claus Weihermueller appointed as regional manager of KEM/TASI Flow Asia Pacific & Middle East Operations. 
Claus has spent the past 15 years working in the field of flow metering and has been living and working in Singapore for eight years. He will promote and further expand the KEM/TASI business in the region, including Litre Meter.

Slim line customisation

Litre Meter’s ability to highly customise its meters has led to the company winning a significant order to supply meters to a company that produces hydraulic systems to the oil and gas industry. The fluid to be measured was Castrol Transaqua HT 2, with a viscosity of 3,95 cSt at 20 degree Celsius. The meters were bespoke slimline ones with a wide turn-down to allow for additional meters on a skid.

VFF positive displacement meters had to be made to operate at different pressures and flow ranges with different connections ranging from a VFF8 meter with a design pressure of 44 Bar, a scale of 0.3-30L/min with 25mm Female BSPP or equivalent size connections up to HP20 Flowmeters designed to work at a pressure of 950 Bar with a scale of 0.1-10L/min and 3/8” MP Autoclave connections.

All the flowmeters were located and certified for in Zone 2, Gas group IIB and Temperature class T3 so had to be EEx D or E. The minimum accuracy had to be within ±1.0% of full scale and the meters were constructed from 316SS quality stainless steel for all wetted parts.

The solutions provided were:

VFF8/690bar/AGPVD/V/9/16″AE MP

VFF8/1035Bar/AGPVD/V/9/16AE MP

HF20/207Bar/AGPDV/V/1″NPT all with


Significantly we were able to offer measurement over the whole of the flow ranges required which competing flowmeter manufacturers were not able to deliver. In addition, the bespoke slimline VFF8 1035bar on drawing enabled the end user to get an additional meter on the skid without having to increase the available space.

Now we are 40

LM1 - Mug shotLitre Meter is 40 this year and to celebrate we are giving away commemorative mugs.

To get yours while stocks last email us at and we will get one in the post.

See you at ACHEMA

Staff from Litre Meter will be at the ACHEMA exhibition in Frankfurt in 2015. We will be joining over 3,000 other exhibitors at the show.

ACHEMA will this year be focusing on products, technologies and solutions for the bio-based economy, industrial water management and innovative process analytical technology. At Litre Meter we have solutions for flow control and measurement in all three areas.

To register for the show visit the ACHEMA website.

Next Generation Flowmeters for Fluid Measurement and Control Solutions

Charles Wemyss, Litre Meter Limited

Types of Flowmeters fall into many categories. One could use the involvement of moving parts and electronics to define this. Mechanical meters, used and invented before domestic electricity was prevalent must be Old Generation. These would include what you and I have outside our houses for the measurement of domestic water. They would also include meters in our gas supply for the measurement of our consumption of gas. The very first turbine meters credited to Woltmann in 1790 were considered for calculating the loss of energy in open canals. It would be true to say that these were used for counting or totalising flow rather than providing an instantaneous rate display or output.

From the Old to the New

Those using electricity or electronics with a moving part like a rotor are also Old Generation as turbine meters have been around for several decades, for example. The first of these were axial turbine types developed, in essence from Woltmann, in the Second World War for accurately determining the fuel consumption of military aircraft and torpedoes. The pick-up or sensor with a magnet and rotating conductor enabled the number of rotations to be counted, totalised and used for rate display.
If we define Next Generation meters as having no moving parts so that the definition encompassed Thermal, Coriolis, Ultrasonic and Electromagnetic, then there would be a modern outlook. Apart from the fact that Faraday tried making an electromagnetic meter to measure the River Thames almost 200 years ago! He only failed because his instrumentation wasn’t sophisticated enough.
The obvious question to ask is: What is Next Generation, What is Current Generation and What is Old Generation? We can be certain that Old Generation does not mean unusable. We can also be certain that Old Generation in some people’s eyes is more than adequate for various tasks. This article explores the provenance of some flowmeter technologies, what might be round the corner and how to select the best meter for each project.

Some new and not-so-new flow measurement techniques:

New Technology

Coriolis, inertial force was first formulated by Gustave Coriolis in 1835 but MicroMotion didn’t release a commercial unit until 1977.

Electromagnetic, proven by Faraday but commercially produced from 1952. *Ultrasonic, from 1963.

Vortex, using the van Karmann effect of the generation of alternate vortices past a bluff body commercially from 1969, famously spotted by Leonardo da Vinci in 1504.

Thermal, hot wire anemometers were used from the early 1900s, commercially from the 70s.

Sonar, unconventional and measures turbulence since 2003.

Optical, measuring the speed and direction of individual particles using a laser beam, in research labs in the 70s and 80s but only commercially used in flare gases.

Traditional Technology

Differential Pressure like an orifice plate or Dall tube with a separate differential pressure transmitter. Also nozzles, pitots, Venturis and wedges. Still the most popular non-domestic meter type.

Positive Displacement, commercially pre 1830s for diaphragm gas meters with sheepskin diaphragms and sheet steel enclosures.

Turbine, first drawn up in 1790, commercially available post Second World War.

Variable Area, available for most of the 20th century.

Low Flow technology and the next ten years

There are various technologies that present themselves for low flow shown below. Many of the others mentioned elsewhere do not scale effectively.

Coriolis: Most manufacturers concentrate on ½” (15mm) and above. The issues of balance and producing thin wall tube to the required dimensional tolerances are hard to overcome. Smaller sizes exacerbate this.

Thermal: Microelectromechanical systems (MEMS), generally 0.01 mm to 0.1 mm in size, consist of a CMOS circuit on a thin silicon substrate. For lower flows these will replace a larger heated element and sensor. Liquids have a massively different thermal conductivity so the same device can measure at grams per hour rather than grams per minute.

Positive Displacement: Generally their purpose is to positively measure a trapped volume of fluid ? either gas or liquid. Gas versions tend to be for higher flows with the most popular one being used for domestic gas measurement. At lower flow the leakage between successive volumes is too large for effective measurement. For liquids where there is more viscosity the PD meters work well. Developments focus on some novel types and constant improvements to existing designs. There is a law of diminishing returns as the smaller the mechanical parts are, the harder they are to manufacture accurately. Also, leak paths are proportionally larger. One of the new types is the pendulum. This has one moving part with low mass and minimal friction loss, enabling it to respond to extremely low flow volume rates from 0.3 litres/hour. Unusually, this unit only works with viscosities up to 5 centiStokes. The rotary piston meter also has one moving part. In terms of flow rate, like most PDs, these prosper on viscosity. At 10 cSt a typical meter will start measuring at 0.08 l/h and when water is measured this increases to 0.4 l/hr.

In line ultrasonic: What happens when the pipes reduce in size and the type where a sensor is clamped on the outside of the pipe is no longer applicable? The sensors are mounted inside the pipe usually contrived in the shape of a U so that the ultrasound is passed between sensors at the base of the U. By knowing the diameter of the tube and the velocity between sensors, the volumetric flow can be calculated. Liquid flow rates down to 2 ml/min can be measured.

So if it’s not the methods of measurement we use that define Next Generation what is it? Perhaps: intelligence? The rise of smart meters i.e. those with digital communications and with the ability to self-verify are undoubtedly modern but were defined decades ago and have been in use for many years.

What’s Next?

Wireless communication is similarly up-to the- minute. HART digital communication has been around since the mid-1980s when it was developed by Rosemount Inc. for a range of measuring instruments, not just flowmeters. The HART foundation was formed in 1993 and the wireless version came along in 2007. So quite modern but Next?
So, is it the flowmeters that inhabit university laboratories and the R&D departments of flowmeter manufacturers that constitute Next Generation? Can we speculate what a cutting edge meter might look like in ten years’ time?

No Moving Parts

It would be fair to say that this Future meter would have no moving parts. This improves the chances of long term use as it would not suffer from mechanical degradation either planned or unplanned. It would ideally be non-invasive i.e. it would fit on the outside of a pipe and nothing would actually breakthrough the pipe wall. Currently, just ultrasonic meters match this criterion so let’s say that’s less than likely and the meter will therefore be non-intrusive. The sensor will break through the pipe wall but won’t impede the flow or perhaps just negligibly. What will the sensor measure, what techniques will it employ? That’s the $64,000 question. A single sensor is less likely as there will have to be a reference point for comparison.
Probably two sensors set apart, then, monitoring a property of the fluid. The clever part will be the intelligence of the signal processing; looking for perturbations in the signal amplitude and comparing it to the next sensor. Dumping thousands of comparisons for the sake of a few, locking onto patterns and pumping out high strength signals. In fact, the real hurdles will be firstly customer acceptance and secondly, electronic component obsolescence. Will the customer accept this meter and will it continue to find the small perturbations in property? Can he see it in action? Does he get a sense of goodness in the signal, in the rejection rate? What if the pipe vibrates, if the temperature ramps up, if the ‘property’ disappears? Then we find out that metering and measuring is about confidence, experience rather than Next Generation.

Bringing the Oil and Gas Industry Up-to-Date

The Oil & Gas industry is relatively conservative, relatively slow moving. The prevalence of HART and 4-20 mA signals decades after their introduction speaks volumes. Wireless, Bluetooth and fancy bus protocols are only just now making significant in-roads offshore. The creep of domestic innovation exemplified by the rise of the smart phone encourages instrument designers to bring their act up-to-date. Most instrumentation can only be compared with the most basic mobile phone. There is an inherent expectation that the modern user will have something easy-to-use, colourful and dangerously (?) customisable. The smartphone has many different uses of course beyond that of making calls. Arguably, it’s an instrument display in its own right. The logical conclusion is that the meter ‘display’ will be with the operator the whole time, in his/her hand. The obsolescence of components that bugs the subsea side of the industry is irrelevant in the actual instrument as this is replaced by the mobile phone and it’s ‘app’.
That still leaves the problem of the fast-moving world of miniature components for the clever parts – that will always be a thorn in the side of designers. Just as with most technologies, we’re not trying to design something to last for 30 years; the likelihood is that it will be overtaken by a new Next Generation device in ten years and then again in twenty years. All we can hope for is that the unit is still working in ten and twenty years and only needs replacing in thirty.
To select the best flowmeter for each application it is not just a question of looking up the first flowmeter you thought of on Google. Nor is it asking the engineer on the next desk or even consulting the internal specification guides issued by your employers. And it certainly shouldn’t be by selecting the cutting-edge meter of the day. It should be by consulting a flowmeter specialist – a specialist that has a wide range of solutions, not just one that is shoehorned into every application. Ideally, an independent specialist who can give unbiased advice and who will, if necessary, recommend an external solution.

Looking to the Future

In conclusion, the Next Generation of flowmeters is already operating, they’re already proven and they’re probably on the specification lists. Most applications can be met, more than adequately, by existing techniques. But the manufacturers aren’t standing still. They’re continually leveraging current technology with creeping demands. It’s more evolutionary than revolutionary but we’re all getting there – safely, economically and technically.