McCrometer invented the V-Cone® in 1985 and has set the standard for cone-type meters ever since.
However, despite this innovation, orifice plates are more widely used differential pressure (DP) flow meters, particularly by engineers for flow measurement projects.
So what are the differences between these two types of flowmeter, and how are they used in various flow measurement projects? Let's take a closer look.
The V-Cone® is a highly customizable flowmeter that measures flow based on the Bernoulli principle. Thanks to a flow detection design that calms vortices and turbulence, this flowmeter maximizes accuracy and minimizes line intrusion.
Its reduction ratio of 10:1 or more gives it great flexibility in a wide range of difficult flow applications with large flow ranges. Thanks to its self-conditioning technology, the V-Cone® requires little or no straight pipework upstream and downstream of the meter.
This makes it an ideal solution for retrofit projects or sites where space and weight are an issue. Offered in line sizes ranging from 0.5″ to 120″, it is suitable for a variety of applications in the oil & gas and industrial segments.
V-Cone® technology is offered in a range of products including Wafer-Cone®, which offers the technology in a flangeless, field-replaceable element, and VM V-Cone®, specially designed for municipal water applications.
The orifice plate is probably the best-known DP flowmeter, as its popularity and "off-the-shelf" qualities have made this disc-shaped device commonplace. Less flexible, the diaphragm meter has a lower measuring dynamic, typically averaging 4:1, and requires up to 40 diameters of straight line upstream and 20 diameters downstream.
There are several variants of orifice plates, such as concentric, eccentric, multipallet and segmental plates, which are implemented according to the medium in the pipe. Changes in process conditions affect the reliability of orifice plate flow readings.
Unlike a V-cone, which can be calibrated over the entire Reynolds range, an orifice plate is not usually calibrated, and accuracy is only guaranteed if it is manufactured and installed precisely to standard.
V-Cones and orifice plates can be built in a wide variety of materials, including exotic ones, at the customer's request.
The orifice plate is less suited to environments where there are flow fluctuations, whereas the V-Cone® can solve problems such as pressure loss and high measurement dynamics.
Where the V-Cône® doesn't compare is in the "commodity" version of the orifice plate. The orifice plate is easy to acquire and well understood by engineers, making it a popular offering with many flowmeter manufacturers.
It's also very simple to produce, whereas V-Cone® is a highly customized quality product, designed and produced to address application-specific concerns.
This customization factor contributes to the higher price of the V-Cone® compared to the more nominally priced orifice plate; the price of the V-Cone® is often offset by the total installed cost and the expected 25+ year life of the meter. For a less customized V-Cone®, the Wafer Cone is a good option, especially for customers who want the reliability of V-Cone® technology but require less customization.
Although both flowmeters are built from durable materials, the orifice plate can be worn away by objects in the flow. The orifice plate is easily worn away by the sharp measuring edge, requiring replacement. The V-Cone® design offers gusseted supports for larger pipe diameters.
Depending on application requirements, it prevents the effects of resonance frequencies, flow-induced vortices, thermal shock and reverse flow scenarios.
In orifice plate applications requiring high measurement dynamics, customers can build parallel pipes to measure both high and low flows.
This additional piping can increase overall equipment cost and space requirements, as two parallel piping systems with the necessary straight passage for orifice plates can take up a lot of space.
The high measurement dynamics of the V-Cone® can solve this problem, as this durable flowmeter can measure over a wider range of flow conditions.
Although it uses the same differential pressure technology, the V-Cone® is most often considered for projects alongside Venturi flowmeters and vortex meters, rather than orifice plates.
If a project doesn't necessarily require a more advanced flowmeter, there's no need to implement anything more complex than an orifice plate.
Nevertheless, both types of flow meter are often used in the same oil, gas and industrial applications, with the exception of those requiring a flow meter with less permanent pressure loss, such as the V-Cone®.
In addition, applications such as offshore platforms and FPSO (Floating Production Storage and Offloading) vessels frequently choose the V-Cone®. Thanks to its minimal straight pipe length requirements, it helps the engineer to meet the project's space and weight restrictions.
When flow changes are not to be expected and straight lengths are not a problem, a basic orifice plate is an economical choice for applications that don't require an advanced flowmeter. It'll get the job done with minimal impact on your budget!
However, if accuracy and reliability are crucial for a project involving delicate factors such as variable flow rates and space and weight restrictions, it's well worth investing in the V-Cone.
This deltaP flow meter is virtually maintenance-free and has a service life of over 25 years. It's a measuring device you can set up and forget about - while the flowmeter collects accurate, consistent data.
Translated from https://blog.mccrometer.com/v-cone-vs-orifice-plate-similarities-and-differences/
