Wednesday, October 31, 2018

Overpressure Protection Devices

Fluid pressure exerts force on any surface area it contacts, as described by the formula F = PA. One practical consequence of this fact is that process vessels and pipelines may catastrophically burst if subjected to excessive fluid pressure. If subjected to excessive vacuum, some vessels and piping may implode (collapse in on themselves). Not only do these potential failures pose operational problems, but they may also pose severe safety and environmental hazards, especially if the process fluid in question is toxic, flammable, or both.

Special safety devices exist to help prevent such unfortunately events from occurring, among them being rupture disks, relief valves, and safety valves. The following subsections describe each of these protective devices and their intended operation. In a P&ID, rupture disks and relief valves are represented by the following symbols:
Overpressure Protection Devices

A rupture disk acts like an electrical fuse for overpressure protection: when the burst pressure is exceeded, the disk ruptures to let fluids escape through it. Safety and relief valves work like self-resetting circuit breakers: they open to relieve pressure, then re-close to seal the process system once more.

Two common causes of process overpressure are piping blockages and overheating caused by fires. Although it may sound ridiculous, a number of fatal industrial accidents have been caused by something as simple as shut block valves that should have been left open. When fluid cannot escape a process vessel, the pumping forces may exceed the burst rating of the vessel, causing catastrophic failure. Fires may also cause overpressure conditions, owing to the expansion of process fluids inside sealed vessels. Overpressure protection devices play a crucial role in such scenarios, venting process fluid so as to avoid bursting the vessel. It should be mentioned that these two causes of overpressure may have vastly differing protection requirements: the required flow rate of exiting fluid to safely limit pressure may be far greater in a “fire case” than it is for a “blockage case,” which means overpressure protection devices sized for the latter may be insufficient to protect against the former.

Overpressure protection device selection is a task restricted to the domain of process safety engineers. Instrument technicians may be involved in the installation and maintenance of overpressure protection devices, but only a qualified and licensed engineer should decide which specific device(s) to use for a particular process system.

For more information on overpressure protection devices, contact Flow-Tech by visiting https://flowtechonline.com or by calling 410-666-3200 in MD or 804-752-3450 in VA.


Reprinted from "Lessons In Industrial Instrumentation" by Tony R. Kuphaldt – under the terms and conditions of the Creative Commons Attribution 4.0 International Public License.

Thursday, October 25, 2018

Portable Industrial Gas Analyzers

SERVOFLEX portable analyzers deliver high performance gas analysis in hazardous and non-hazardous areas. Using the same precision sensing technology of Servomex fixed analyzers, these ergonomically designed, easy to use portable analyzers provide compact, precise and reliable gas analysis in a wide range of applications from labs and plants to food production and universities.

The portable product line includes:
  • Micro i.s. 5100 - Intrinsically safe analyzer measures oxygen, carbon monoxide or carbon dioxide
  • MiniFoodPack 5200 -  Benchtop analyzer for checks / quality control in Modified Atmospheres Packaging
  • MiniHD 5200 - Resilient IP65 analysis of oxygen, carbon monoxide and carbon dioxide in industrial applications
  • MiniMP 5200 - Benchtop analyzer offering single or dual measurements of oxygen and carbon dioxide
For more information, view the video below. Contact Flow-Tech in Maryland and Virginia with application questions. They can be reached at 410-666-3200 in Maryland, 804-752-3450 in Virginia, or by visiting https://flowtechonline.com.

Monday, October 15, 2018

Part 2 - A Shift for Process Instrumentation: Solving Process Control Problems with Cloud-Based Solutions

Automated Device Commissioning
Click for larger view.
ADC is an abbreviation for "Automated Device Commissioning", sometimes referred to as "Smart Commissioning". From a practical standpoint, it is a set of engineering techniques and processes to check, inspect and test every operational component of a project. Workflows incorporating lean engineering can benefit from designing instrument configurations before the hardware is actually delivered to the facility.

ADC/Smart Commissioning can be used to do the following:
  • Reduce commissioning time to a fraction of the original hours needed.
  • Mechanically binds control configuration.
  • Reduces the need to verify I/O assignments.
  • Helps avoid costly errors in wiring and termination.
  • Automates intelligent device testing and documentation.
Use of ADC/Smart Commissioning promotes efficiency for automation projects.  In the early stages of projects, engineers used to have to deal with repetitive and complicated tasks to get the project set up.  Now with this new approach, teams of engineers can work on the project collectively, and at the same time, without needing to be physically at the same site.  Cloud-based engineering activities are also handled separate from the project hardware so the schedule doesn't necessarily drive the project.

ADC/Smart Commissioning helps engineers to confirm that the right transmitter is landed on the correct controller input/output module. (I/O)  If a mismatch is determined, the engineer can fix the mismatch in real time.  Then, once the hardware configuration is confirmed, the user can perform loop checkout as well.  The tool's loop test checkout template is simply modified using Excel and then the ADC/Smart Commissioning function runs the test according to the project plan.

In the industrial sector, capable engineers are retiring from the workforce and manufacturing companies are being forced to accomplish their work with fewer experienced employees. At the same time, as always, there continues to be the need to reduce maintenance costs and operating costs. Companies are looking for new answers and solutions to optimize project results  to track performance, monitoring, and reliability of process instrumentation.

Cloud-based engineering tools have the opportunity to make employees more productive and to drive efficiencies in manufacturing plants.  They reduce engineering hours and make commissioning steps more efficient, shortening device commissioning time.  They also have the potential to improve user safety, streamline usability, and significantly decrease budges for maintenance.

Flow-Tech, Inc.
https://flowtechonline.com
In MD 410-666-3200
In VA 804-752-3450

Saturday, September 29, 2018

The Hoffer Flow Controls HIT-4U Flow Rate Indicator and Totalizer

HIT-4U
The HIT-4U, manufactured by Hoffer Flow Controls, is a battery, DC or loop-powered microprocessor-based flow rate indicator and totalizer with data logger and Modbus Communications Protocol. The instrument can accept a low-level signal from a magnetic type pickup coil, a DC pulse signal, contact closure or modulated carrier pickup (MCP/RF). Pulses from the signal input are converted into volume and rate values based on flowmeter calibration settings stored in the instrument. The total volume and flow rate are displayed on a two-line liquid crystal display (LCD). A 4-20 mA analog signal proportional to the flowrate is output on the current loop. The HIT-4U is configurable from the instrument front panel keypad or via Modbus communications.

For more information, download the HIT-4U Flow Rate Indicator and Totalizer Users Manual here, of view the manual in the embedded viewer below.

Flow-Tech, Inc.
https://flowtechonline.com
In MD 410-666-3200
In VA 804-752-3450

Tuesday, September 25, 2018

Presentation: The Yokogawa YS1000 Series as Replacement for Siemens/Moore 353

Siemens has recently discontinued their popular 353 SLC controller (also referred to as the Moore 353). This process controller was very popular and it's discontinuation leaves many companies without a path forward.

This video is a complete presentation on why and how the Yokogawa YS1000 Series is an excellent replacement for Siemens 353's in the field. To stop on a specific screen, push the pause button.


Wednesday, September 12, 2018

Brooks Instrument

Brooks Instrument is the global leader in flow and pressure instrumentation, enabling precision process control for industrial and semiconductor applications.

Products include:
  • Mass Flow Controllers & Meters
  • Variable Area Flow Meters (Rotameters)
  • Pressure & Vacuum Products
  • Vaporization Products
  • Semiconductor Products

Represented in Maryland and Virginia by Flow-Tech, Inc.
https://flowtechonline.com
410-666-3200 MD
840-752-3450 VA