Hydrocarbon Processing - November 2021 - 42
Engineering and Construction
* Thickness of the support plate;
bolt holes location and size
* The centerline of the gauge
chamber will remain at least
8 in. from any ferrous material
to comply with API 5516
* Any project specifications for
support plates will determine
design requirements such
as size, thickness, etc.
FIG. 12 shows a typical drawing of a
magnetic level gauge with support plate,
and FIG. 13 shows standard support detail
on a vessel that can be used as a reference
in designing the support on the level
gauge chamber.
Bolt holes orientation for a level
gauge process connection flange.
Bolt holes are placed in multiples of four,
should be equally spaced, and pairs of
bolt holes should straddle fitting centerlines,8
meaning:
*
For a vertical flange face (the
flange face is the vertical and the
line is horizontal), the bolt holes
should straddle the vertical and
horizontal centerlines (FIG. 14).9
* For a horizontal flange face
(the flange face is horizontal,
and the line is vertical above
or vertical down), the bolt
holes should straddle the plant
north centerlines (FIG. 15).9
This " natural " centreline rule for
flanges is known, understood and followed
by all responsible equipment
manufacturers and pipe fabricators. It is
essential that the bolt holes orientation
of the vessel flange and level gauge flange
are the same; otherwise, the gauge will
not fit to the vessel. When the mechanical
vessel reached the site in a modularized
project, the bolt holes of the vessel
flange (for mounting the level gauge)
were not straddled across the centerlines
and were rotated 1° in a clockwise
direction. The instrument vendor was
informed of the error and asked to rotate
the mating flange of the level gauge chamber
connection 1° counter-clockwise so
the flanges' bolt holes were aligned.
FIG. 14. Bolt holes orientation for a
vertical flange.
Gauges in high-pressure rating.
Few manufacturers produce magnetic
level gauges that can withstand a highpressure
rating of 2,500 lb and 10,000 lb.
Moreover, 10,000-lb rated flanges are not
covered in ASME B16.5 standards-the
API 6A standard is followed for 10,000lb
rated flanges and bolts, and great care
must be taken when selecting these gauges.
Most of the time, the designs are proprietary,
but the design must still meet
the project specifications: all materials
should be rated to design pressure and
temperature of the level gauge; the liquid
chamber should be designed as per Boiler
and Pressure Vessel code, ASME Section
VIII, Division 1; and all bolting and
torque values, size categorization (113/16
in. or 29/16 in.) and flange facing must also
comply with API 6A.
FIG. 15. Bolt holes orientation for a
horizontal flange.
42 NOVEMBER 2021 | HydrocarbonProcessing.com
Takeaway. Magnetic level gauges are safe
and reliable instruments of level measurement
and are widely used in the energy
and chemicals industries. Since the size
of level gauges vary (based on c-c length
and float length), the best practices and
methodologies of selection detailed here
can aid in satisfactory installation of magnetic
level gauges. Detailed modeling of
a modularization project allows factors
such as nearby steelworks, grating, beam
supports, access, customized chamber
support and float removal clearance to be
determined well in advance, saving space,
cost and schedules. This approach to
modular construction has been adopted
by many companies. With emerging technologies,
the engineering and construction
industry is evolving and adopting
advanced techniques to execute projects
in a more efficient manner.
LITERATURE CITED
1
Modular Building Institute, " What is modular construction? "
2021, online: https://www.modular.
org/HtmlPage.aspx?name=why_modular
2
LJ Star, " How does a magnetic level gauge work? "
March 2020, online: https://www.ljstar.com/howdoes-a-magnetic-level-gauge-work/
3
Himes,
T., " Benefits of a top-mount design for
level indicator, " WIKA, June 2018, online: https://
blog.wika.us/products/level-products/top-mountdesign-for-level-indicator/
4
Himes,
T., " The magnetic level indicator working
principle: Simple and effective, " WIKA, October
2018, online: https://blog.wika.us/knowhow/
magnetic-level-indicator-working-principle/
5 Magnetrol/Ametek, " Magnetic
level indicators, "
online: https://www.magnetrol.com/en/magnetic-level-indicators
6
American
Petroleum Institute (API) Recommended
Practice 551, " Process measurement, " 2nd Ed.,
February 2016.
7
Orion Instruments, " Magnetic level indicators, "
online: https://msjacobs.com/images/msj/PDFs/
Orion-Instrument-Magnetic-Level-Indicators.pdf
8
American Society of Mechanical Engineers
(ASME) B16.5-2013, " Pipe flanges and flanged
fittings: NPS 1/2 through NPS 24, Metric/inch
standard, " 2013.
9
EWP, " Bolt hole orientation, " online: http://www.
wermac.org/flanges/flanges_bolt-hole-orientation.
html
SHIKHA SARDANA is a Control
Systems Engineer with more than
9 yr of experience working on
various greenfield and brownfield
projects in the chemicals,
petrochemicals, and oil and gas
(upstream and downstream)
industries, among others. Her main responsibilities
for Fluor, New Delhi include carrying out engineering
and design activities for proposals, FEED and EPCM
projects. Ms. Sardana earned a BTech degree in
instrumentation engineering and an MBA.
MADHUMITA SINHA works in
Control Systems at Fluor Daniel,
India. She has more than 16 yr of
work experience with companies
such as Jacobs Engineering,
Petrofac and Fluor, and has worked
across various industries, including
upstream and downstream oil and gas, chemicals
and fertilizers, dyes and petrochemicals. Ms. Sinha
has executed a variety of projects in the detail
engineering, EPC, FEED and basic engineering
phases in both LSTK and cost reimbursable formats.
Her global experience includes leading various
projects in India, UAE, Europe and Kazakhstan.
https://www.modular.org/HtmlPage.aspx?name=why_modular
https://www.modular.org/HtmlPage.aspx?name=why_modular
https://www.ljstar.com/how-does-a-magnetic-level-gauge-work/
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https://blog.wika.us/knowhow/magnetic-level-indicator-working-principle/
https://blog.wika.us/knowhow/magnetic-level-indicator-working-principle/
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http://www.wermac.org/flanges/flanges_bolt-hole-orientation.html
http://www.HydrocarbonProcessing.com
Hydrocarbon Processing - November 2021
Table of Contents for the Digital Edition of Hydrocarbon Processing - November 2021
Contents
Hydrocarbon Processing - November 2021 - Intro
Hydrocarbon Processing - November 2021 - Cover1
Hydrocarbon Processing - November 2021 - Cover2
Hydrocarbon Processing - November 2021 - Contents
Hydrocarbon Processing - November 2021 - 4
Hydrocarbon Processing - November 2021 - 5
Hydrocarbon Processing - November 2021 - 6
Hydrocarbon Processing - November 2021 - 7
Hydrocarbon Processing - November 2021 - 8
Hydrocarbon Processing - November 2021 - 9
Hydrocarbon Processing - November 2021 - 10
Hydrocarbon Processing - November 2021 - 11
Hydrocarbon Processing - November 2021 - 12
Hydrocarbon Processing - November 2021 - 13
Hydrocarbon Processing - November 2021 - 14
Hydrocarbon Processing - November 2021 - 15
Hydrocarbon Processing - November 2021 - 16
Hydrocarbon Processing - November 2021 - 17
Hydrocarbon Processing - November 2021 - 18
Hydrocarbon Processing - November 2021 - 19
Hydrocarbon Processing - November 2021 - 20
Hydrocarbon Processing - November 2021 - 21
Hydrocarbon Processing - November 2021 - 22
Hydrocarbon Processing - November 2021 - 23
Hydrocarbon Processing - November 2021 - 24
Hydrocarbon Processing - November 2021 - 25
Hydrocarbon Processing - November 2021 - 26
Hydrocarbon Processing - November 2021 - 27
Hydrocarbon Processing - November 2021 - 28
Hydrocarbon Processing - November 2021 - 29
Hydrocarbon Processing - November 2021 - 30
Hydrocarbon Processing - November 2021 - 31
Hydrocarbon Processing - November 2021 - 32
Hydrocarbon Processing - November 2021 - 33
Hydrocarbon Processing - November 2021 - 34
Hydrocarbon Processing - November 2021 - 35
Hydrocarbon Processing - November 2021 - 36
Hydrocarbon Processing - November 2021 - 37
Hydrocarbon Processing - November 2021 - 38
Hydrocarbon Processing - November 2021 - 39
Hydrocarbon Processing - November 2021 - 40
Hydrocarbon Processing - November 2021 - 41
Hydrocarbon Processing - November 2021 - 42
Hydrocarbon Processing - November 2021 - 43
Hydrocarbon Processing - November 2021 - 44
Hydrocarbon Processing - November 2021 - 45
Hydrocarbon Processing - November 2021 - 46
Hydrocarbon Processing - November 2021 - 47
Hydrocarbon Processing - November 2021 - 48
Hydrocarbon Processing - November 2021 - 49
Hydrocarbon Processing - November 2021 - 50
Hydrocarbon Processing - November 2021 - 51
Hydrocarbon Processing - November 2021 - 52
Hydrocarbon Processing - November 2021 - 53
Hydrocarbon Processing - November 2021 - 54
Hydrocarbon Processing - November 2021 - 55
Hydrocarbon Processing - November 2021 - 56
Hydrocarbon Processing - November 2021 - 57
Hydrocarbon Processing - November 2021 - 58
Hydrocarbon Processing - November 2021 - 59
Hydrocarbon Processing - November 2021 - 60
Hydrocarbon Processing - November 2021 - 61
Hydrocarbon Processing - November 2021 - 62
Hydrocarbon Processing - November 2021 - 63
Hydrocarbon Processing - November 2021 - 64
Hydrocarbon Processing - November 2021 - 65
Hydrocarbon Processing - November 2021 - 66
Hydrocarbon Processing - November 2021 - 67
Hydrocarbon Processing - November 2021 - 68
Hydrocarbon Processing - November 2021 - 69
Hydrocarbon Processing - November 2021 - 70
Hydrocarbon Processing - November 2021 - 71
Hydrocarbon Processing - November 2021 - 72
Hydrocarbon Processing - November 2021 - 73
Hydrocarbon Processing - November 2021 - 74
Hydrocarbon Processing - November 2021 - 75
Hydrocarbon Processing - November 2021 - 76
Hydrocarbon Processing - November 2021 - 77
Hydrocarbon Processing - November 2021 - 78
Hydrocarbon Processing - November 2021 - 79
Hydrocarbon Processing - November 2021 - 80
Hydrocarbon Processing - November 2021 - 81
Hydrocarbon Processing - November 2021 - 82
Hydrocarbon Processing - November 2021 - 83
Hydrocarbon Processing - November 2021 - 84
Hydrocarbon Processing - November 2021 - 85
Hydrocarbon Processing - November 2021 - 86
Hydrocarbon Processing - November 2021 - 87
Hydrocarbon Processing - November 2021 - 88
Hydrocarbon Processing - November 2021 - 89
Hydrocarbon Processing - November 2021 - 90
Hydrocarbon Processing - November 2021 - Cover3
Hydrocarbon Processing - November 2021 - Cover4
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_200904
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200903
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200902
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200901
https://www.nxtbookmedia.com