HVAC Energy Management - Thermal Metering With Non-Invasive Technology

Ultrasonic flow measurement is an optimal choice
for thermal metering, with it non-invasive installation.
Image courtesy Flexim Americas Corp.

The modern business climate has, for some time now, been spooling up demand for accountability and, even more so, efficiency. Whether you think of efficiency as "doing more with less" or just avoiding the expenditure of financial, human, or natural resources the end result is the same and calls for similar prerequisites.

We live in a society of buildings, each with a mapped out function. Most buildings are predominantly occupied by people, bringing a requirement to maintain temperature, relative humidity, and air quality at levels of suitable comfort for human occupants. The energy consumption involved with providing that level of comfort stands as a bold line item in the operating expense ledger for any building. That is where accountability and efficiency come in. It is in the building stakeholders' interest to have knowledge regarding rates and quantity of thermal energy usage, as well as efficiency measures of delivered output per unit of input energy.

HVAC (Heating, Ventilation, Air Conditioning) primarily is an endeavor that generates and moves thermal energy throughout an enclosed space. Commercially available technology now allows a building operator to accurately measure that movement of thermal energy throughout a system or building. The process is generally called BTU metering and has a number of justifiable benefits.

• Real time equipment performance measurement.
• Sub metering can indicate specific areas of consumption.
• Ability to directly bill multiple tenants in a single building for their thermal energy usage.
• Monitor and balance energy flows.

BTU metering essentially involves inlet and outlet temperature measurement of heat transfer liquids, along with their flow rate. While the principle is simple, the intricacies of the measurement methods and equipment accuracy can have a substantial impact on the accuracy, and thus the benefit, of the measurement data. Additionally, adding more instrumentation to an already complex system can create an additional on-going maintenance and calibration burden to retain the necessary levels of accuracy and function. Success at gaining the benefit of the performance data while minimizing the additional maintenance burden due to the instrumentation should be the goal.

One solution calls for the use of clamp on ultrasonic flow meters to measure liquid flow, coupled with temperature measurement in a single unit that will perform necessary calculations and provide output data in useful engineering units. An overarching benefit of the clamp on meter is its non-invasive nature, allowing its retrofit to in-place systems with no disturbance to existing piping. Here are some other characteristics of a highly effective BTU measurement unit:

• No wear mechanism as part of the flow measurement unit
• Traceable accuracy of flow and temperature measurements
• Simple installation in new or retrofit applications without disruption to system operation
• Reliable and maintenance free operation
• Accurate measurement from near zero flow rate to maximum system flow
• Stable sensing with no zero drift
• Communications protocol to match building energy management system
• Large storage cache for data, in case of communication failure
• Common output signals, 4-20 ma or other, usable with selected ancillary equipment

Selecting the right equipment or instrumentation is the most important step along the path of adding measurement capability to increase efficiency. Without a solid stream of reliable data, useful decisions become difficult. Contact a product application specialist and share your goals and challenges. Leverage your own knowledge and experience with their product application expertise to develop an effective solution.

BTU Metering Using Non-Invasive Flow Measurement from Classic Controls, Inc.

Industrial Process Pressure Transmitters

One of many variants of industrial pressure transmitters.
Image courtesy Yokogawa USA

The measurement and control of fluid pressure is ubiquitous throughout many industrial processes. Measurements of pressure, directly and indirectly, provide real time information about what is happening in places that cannot be seen, such as inside a pipe, tank, or machine. The very nature of “process” suggests movement and change, the control of which is necessary to produce a consistent desirable outcome. Industrial pressure transmitters employ specific technologies and physical principals to derive a measurement of process pressure, then deliver or transmit, the measured value to a controller or recording device.

Fluid pressure tells a process operator much about what is currently happening. The pressure variable can be used to determine, among many industrial process elements:

• Degree to which the process is conforming to a recipe or specification
• Whether machinery is performing within its specified operation range
• If conditions of the process remain within the bounds established for safety
• A quantity measurement of flow, mass, or volume

Global industrial processes have widely varying physical arrangements, operating environments, and measurement requirements. Manufacturers of industrial pressure transmitters have responded with an immense array of transmitter technologies, arrangements, and configurations. When selecting the best suited pressure transmitter for your application, consult a sales engineer and consider some of the following:

• Signal requirements – Type, distance, possible sources of interference
• Device environment – Hazards, extreme conditions of temperature or corrosion
• Accuracy and stability of measurement
• Response time to changes in the process condition
• Ratings and certifications required for the device
• Configuration, arrangement, and mounting aspects of the transmitter device

Explore the differing technologies and how they can be best applied to implement or improve your process. Experienced sales engineers are a useful sounding board for discussing your needs. Share you process measurement challenges with them and leverage your own knowledge and experience into an effective solution.

Coalescing Filters For Compressed Air

Coalescing filters for industrial compressed air service.
Image courtesy Parker Hannafin - Balston Div.

Coalescing filters remove liquid aerosols from a gas by causing very small droplets to contact others, forming successively larger liquid droplets that eventually are moved via gravity to a drain. A combination of filter media and housing properly direct an inlet stream to maximize the combining, or coalescing, of the fine droplets. The filter media will also serve to trap solid particulates, as well. An automatic drain arrangement is a useful feature that prevents accumulation of liquid in the filter housing without operator attention.

Compressed air systems will typically produce output that contains moisture and small amounts of liquid lubrication oil. Leaving the compressor, the air is hot. As it cools, the moisture will condense in the piping system and utilization equipment without a means to remove it. Coalescing filters, properly located throughout the system, will trap and remove liquids entrained in the compressed air stream. The nature of the filter media also results in efficient capture of solid contaminants, such as rust, dust, welding flash and more.

The installation must route the compressed air through the filter in the proper direction. Improperly piped units can have their automatic drain function inhibited, leading to failure and a need to reconnect the unit correctly. Size selection is simplified with tables providing maximum flow rate for rated filtration performance. Oversizing a selection will not produce a negative impact. The filter media pressure drop increases as solids are collected and retained, requiring replacement when pressure drop is excessive.

Share your compressed air system requirements and challenges with filtration specialists. Leverage your own knowledge and experience with their product application expertise to develop an effective solution.

Compressed Coalescing Filters for Industrial Use from Classic Controls, Inc.

Pressure Regulating Valves

Pressure regulating valve, or pressure regulator.
One of many types.
Image courtesy Cash Valve

Pressure regulating valves (PRV) are common components of many processes and equipment. The function of a PRV is to maintain a desired outlet fluid pressure under varying conditions of supply pressure or outlet flow demand.

Many variants exist in the market, each specifically designed to address a range of process conditions or offset a performance characteristic deemed undesirable in another design. Each has a suitable place in the range of possible applications, with cost, size, construction material and complexity primary differences among the offerings.

In its simplest form, a pressure regulating valve (PRV) consists of a flow restricting element, a measuring element, and a setpoint element. Outlet pressure applies force to the measuring element, often a diaphragm. As the outlet pressure increases, the diaphragm will move the flow restricting element toward the closed position, reducing the flow from the inlet. The restricting element is commonly a plug, disk, or some other recognizable valve trim arrangement. The setpoint element, likely a spring, provides a counterbalancing force on the diaphragm. When the force applied to the diaphragm by the outlet pressure reaches equilibrium with the counterbalancing force applied by the spring, movement of the restricting element stops. In this way, outlet pressure is controlled without the need for electric power, sensors, transmitters, or even a process controller. The entire assembly is self-contained and requires little attention.

Selecting a PRV for an application requires coordinated consideration of process performance range, desired conditions, and valve attributes to produce a selection that will provide the desired service. A valve improperly selected for an application may perform poorly. Some of the items to be considered include:

• PRV Type
• Body size
• Construction
• Pressure Ratings
• Maximum Flow Rate
• Outlet Pressure Range
• Accuracy
• Inlet Pressure
• Orifice Diameter
• Response Speed
• Turn-Down Ratio

A PRV is not a safety device. An independent means must be provided to protect the system from excessive pressure. Product specialists are a good source of help in selecting a properly sized and configured valve for an application. Share your fluid process control challenges with a product application specialist. Leverage your own process knowledge and experience with their product application expertise to develop an effective solution.

Flow Measurement in Subsurface Pipes

Ultrasonic flow measurement, properly configured, can be the preferred solution for flow measurement in water and wastewater pipes, especially those in subsurface locations. Demands for increased monitoring of system flow at numerous points throughout a network or system create a need to install flow measurement instrumentation on existing pipes that are unlikely to have built-in accommodations for the needed sensors.

Ultrasonic flow measurement transducers are mounted on the exterior of existing piping and require no pipe cutting or service interuption to install. The rugged transducers are suitable for subsurface installation and provide long term uninterupted operation. Ultrasonic flow measurement functions over a wide range of flow, providing accurate data during normal, peak, and off-peak hours. The data derived from the measurements can also be used for leak detection. Data output from the instrument can be used locally or transferred by a number of methods to remote monitoring stations for system wide analysis.

The video provides some additional application advantages of ultrasonic flow measurement for subsurface pipe applications. Share your flow measurement challenges of all types with process measurement specialists. Leverage your own knowledge and experience with their product application expertise to develop effective solutions.

Auma Heavy Duty Electric Valve Actuators

Cutaway view of electric valve actuator.
Image courtesy Auma Actuators, Inc.

Electric actuators are used to enable remote control of industrial valves, allowing complex processes to be managed and controlled by remotely located control systems. Other means, including hydraulic and pneumatic, are used as  motive forces for valve actuators, but electric actuators bring a particular set of features that make them an advantageous choice for many applications.

Valve actuators are available in a wide range of variants to suit every application scenario. Auma, a globally recognized manufacturer of electric actuators, manufactures heavy duty actuators for demanding applications throughout every industry. Specializing in electric actuators, the company keeps their design and engineering efforts focused on a single product, its performance, reliability, and ruggedness.

• Part turn, linear and multi-turn operation
• Large selection of torque ranges
• Variable or fixed speed operation
• Controller options ranging from simple open-close to micro-positioning with logging of operating data or fieldbus interface
• Numerous gearbox options and mountings to accommodate any application
• Enclosures rated for a variety of installations, including underwater.

Learn more about the electric actuators from Auma. Share your valve and damper automation challenges with industrial application experts, leveraging your own knowledge and experience with their product application expertise to develop effective solutions.

Electric Actuators for Industrial Valve Automation from Classic Controls, Inc.

Fox Thermal Instruments Releases New Gas Flowmeter Targeted at Oil and Gas Operations

The FT4X thermal mass flow meter accommodates
inline, insertion, and retractor installations.
Image courtesy Fox Thermal Instruments, Inc.

Keeping up to date on the latest product information....

Fox Thermal Instruments, an acknowledged innovator in thermal mass flow technology and instruments, has released a flow meter targeted for gas flow measurement in the oil and gas industry. The FT4X delivers a long list of advanced and useful features for flare and waste gas monitoring, gas studies, royalty and allocation, and general gas flow research.

The instrument utilizes a constant temperature differential technology to measure gas or air mass flow, employing two precision RTD sensors. One temperature sensor follows the media temperature, while the other is heated by the instrument electronics to maintain a constant temperature differential between the two sensors. The amount of applied heat to maintain the differential is proportional to the mass flow rate. A linearized 4-20mA output signal is the final output of the transmitter.

The flow meter is available for inline or insertion installation, along with another variant that features retraction of the instrument from the line without flow interruption. Various probe lengths accommodate line sizes to 70 inches. Flow bodies, flow conditioners, and other accessories are available to customize the instrument assembly to fit each application.

There is a wealth of additional information provided in the brochure included below. Share your flow measurement challenges and requirements for process measurement specialists. Leverage your own knowledge and experience with their product application expertise to develop effective solutions.

Thermal Mass Flow Meter for Oil & Gas Applications from Classic Controls, Inc.