Diamond Thermal Systems
Tim Mullen
Specialize in Industrial Electric Heat Trace Applications
Since 2003 – primarily focused on Power Industry
Skill sets and Knowledge base for Gas-fired cogeneration facilities
Best Practices:
Electric Heat Trace Systems and
Winterization
Description & Objective of a Freeze Protection System
Realities of Most Operating Plants
What to expect from an Audit
Winterization Best Practices
Description: Electric Heat Trace System
Control
Power Distribution
Heating cable and accessories
Description: Electric Heat Trace System
Control - various methods
Full Control Panel / PLC
Temp Controller
Tstat
Breaker
Ambient Sensing (total system)
Line Sensing (individual line)
Diamond Thermal Systems
Division of Benchmark Industries, Inc
Typical Ambient Sense Power Distribution Panel
STANDARD 12, 30 AND 42 POLE VERSIONS
Power Available Light
Panel Energized Light
Three Position Selector Switch
NEMA 4 or 4X Enclosure
Description: Heat Trace Cable and Accessories
Self Regulating electric heat trace cable
Mineral Insulated electric heat trace cable
Description: Heat Trace Cable and Accessories
Objectives of a properly functioning heat trace system:
1. Safeguard against catastrophic failures caused by freeze-up
1. Plant trip
2. Plant “no start”
2. Maintaining critical process availability
1. Instrumentation
2. Lube oil
3. Boiler Feed
4. Fire Suppression/Deluge Lines
5. Plant service air
Realities of most Plants:
Maintenance and troubleshooting are a nightmare:
Initial Construction
Ongoing Operations
Maintenance and troubleshooting are a nightmare:
Initial Construction = Adversarial
1. Poor installations during construction – lack of installation
specs and lack of expertise
2. “Ganging” heat trace lines onto circuit breakers – save $$ in
bid process
3. Poor or non-existent labeling of HT circuits
4. NO MONITORING at time of construction – HT systems are
always at end of construction
Poor Installation Practice: SR Cable
Poor Installation Practice: SR Cable
Poor Installation Practice: MI Cable
Poor Installation Practice: MI Cable
Poor Design/Install Practice: “Ganging” heat trace lines
Poor Design/Install Practice: Labeling
Correct tubing bundle specified?
Correct tubing bundle specified?
Correct Instr. Enclosure Specified?
Correct Instr. Enclosure Specified?
No “system” approach to sample line
and instrument enclosure
Realities of most Plants:
Maintenance and troubleshooting are a nightmare:
Ongoing Operations
1.
Maintenance on operating devices (pumps, valves, etc)
2.
Insulation problems
3.
Moisture intrusion from poor installation practices
4.
“As Built Drawings” rarely reflect final installation
5.
NO MONITORING – you know you have a problem after it’s too late
Maintenance on Operating Devices
Moisture Intrusion
Realities of most Plants:
Maintenance and troubleshooting are a nightmare:
How to overcome these realities?
Utilize “Best Practices”
1. Audit of Heat Trace system
A. Repair / Replace recommendations
B. Prioritization by plant personnel
2. Specifications
A. AUDIT: ensure you get necessary information
B. PRODUCT: cable – enclosures & bundles
C. INSTALLATION: piping – instrumentation
3. Monitoring of (at least) critical applications
4. Heat Trace Specialists
Audit Specifications:
1.
Power Distribution Panel
Amperage / Ohms / Megohms
2.
Junction Boxes
Review of physical installations
Labeling of Junction Boxes
3.
Insulation issues
Damaged - Moisture Intrusion
4.
Report
ALL of the information that you
need to make appropriate decisions
Audit Specifications:
A. Repair / Replace recommendations (can potentially save
significant costs based on repairing cable (MI)
B. Prioritization by plant personnel
C. Audit - ensure you get necessary information
(amperage, ohms, megohms)
By Breaker - By HT line – Descriptions – Pictures
D. Format for Year – over – year comparisons
Best Practices
Define priority of found “issues” with plant personnel and develop
list of recommendations with pricing (repair vs. replace)
www.DiamondThermalSystems.com
PROBLEM LINES SUMMARY
Location :
Pooleville, TX
Date :
Tech:
Panel #
Brk #
Brk A
10/15/2012
Tim, Roy, Teo, Aaron, Dan
Brk Ohm
11BGA10GS007 (#1)
1
20.6
6.25
11BGA10GS007 (#1)
5
16.4
11BGA10GS007 (#1)
6
20.5
11BGA10GS007 (#1)
10
11BGA10GS007 (#1)
17
Brk
MegOhm
Pass / Fail
.5
F
6.8
.1
F
6
1.4
F
4.8
9.2
0
F
16.5
6.3
.1
F
Line #
Breaker Comments
Repair / Replace Comments
$$$
FOUND OFF --- EXTRA NOTES: Panel front "alarm" light broken - 120v 18mA red 800E-3N5R
SER.A Allen Bradley - red exterior threader lens missing.
282
Unit 1 blow down tank above ground - MI cable number 20E2L - 2S -110
don't worry about it - David S 10/25/12
0
FOUND OFF - INRUSH
0
201
TRIPPED. Next to LP drum on top of HRSG #1, cold lead is cut. D/MIQ-70E2L-2S - 60
Roy to replace cold lead
650
406
HRSG #1 top enclosure box west side platform far left (north) box-no faults found but self reg
polymer found up against the ground braid. Circuit tested good after wires were moved.
Roy to add "pants" to existing heat trace inside of power
connection kit
135
TRIPPED. Top of HRSG, west side at wind break. D/MIQ-70E2L-2S-60-949
all on top of HRSG #1. Line needs to be strippped - many
valves/instruments
1387.15
213
11BGA10GS007 (#1)
20
18
6.8
0
F
11BGA10GS007 (#1)
25
17.6
6.8
0
F
One of three identical MI lines on top of HRSG #1 fed from self reg power connection boxes on
the east side. All failed meg test. Cable is a A form K cable, 919K-06-04. Grommet missing from
far North Clox power connection kit. Tubing bundle should be OK
Change out MI cable - install new cable in place of old
625
218
F
One of three identical MI lines on top of HRSG #1 fed from self reg power connection boxes on
the east side. All failed meg test. Cable is a A form K cable, 919K-06-04
Change out MI cable - install new cable in place of old
625
218
One of three identical MI lines on top of HRSG #1 fed from self reg power connection boxes on
the east side. All failed meg test. Cable is a A form K cable, 919K-06-04
Change out MI cable - install new cable in place of old
625
Heater inside instrument enclosure on East side of HRSG #1
replace heater inside of enclosure
850
218
11BGA10GS007 (#1)
25
17.6
6.8
0
11BGA10GS007 (#1)
25
17.6
6.8
0
F
11BGA10GS007 (#1)
25
17.6
6.8
0
F
409
Best Practices
Define priority of found “issues” with plant personnel and develop
list of recommendations with pricing (repair vs. replace)
Panel
10BGA10GS006 (#3)
Brkr #
24
Description / Findings
Amp
8.9
Ohm
26
Meg
0
Vlt
120
Status
30E2-L2S/90/534 120/4/12 7234; Located under IP roter air cool line on S end; TDR read show
need a cold lead and 15ft hot
ready to quote - repair
Line #
315B
P/F
Fail
Price
$ 1,440.00
Audit Typical results:
•
Each Panel will be loaded with 20 – 24 Brkrs
•
Each Brkr will have 4 – 8 heat trace lines associated with
it
Audit Typical results:
•
2012 – 2013 – 2014 random sampling of Sites
•
total breakers audited
•
•
Total breakers FAILED
•
•
2717
411
15 percent on average
Audit Typical results for TEXAS sites
•
2012 – 2013 – 2014
•
total breakers audited
•
•
Total breakers FAILED
•
•
1128
194
17 percent on average
Specifications
A. PRODUCT: cable – enclosures & bundles
B. INSTALLATION: piping – instrumentation
Specifications
A. PRODUCT:
Cable
Specific application (temp range, etc)
Manufacturer’s product spec’s
Design software & reports
Enclosures & bundles
Specifications: Instrumentation
1. Sample Lines
1.
Is the heat trace “protected” from the high temperature of
the line that it is supposed to keep warm?
A. Pressure / Temperature ratings of tubing bundle vs actual
application
2. Instrument Enclosure
1.
2.
Heater sized correctly? Heater working?
Enclosure itself – “not all enclosures are created equal”
3. System Concept – critical to proper fit and function
System concept is critical
to proper fit and function
Specifications - Installation
Installation:
If you write a
spec for
what you
expect….this
can be your
outcome!
3.
“Monitoring Systems”
The cost of plant trip/no-start vs. knowing when you are starting
to have a problem, and having the time to fix it
Even with proper audits – “stuff happens”
Types of Monitoring available:
“Sneaker-net” lights on panel or on pipe (end of circuit)
1. Low cost to install
2. Low cost to operate (“have to pay the operators anyway”)
3. Not very reliable – lights burn out, don’t necessarily
provide accurate information
4. Doesn’t provide any diagnostic information
Best Practices:
Types of Monitoring available:
1.
Current – good but limited
2.
Temp/Current – better, and useful for diagnostics
3. Temp/Current/GFI – best for diagnostics and predictive
maintenance
4. COST has been the single biggest issue with adding a Monitoring
system after initial install is complete
5. Wireless COST for hardware is comparable to “Wired” but install
cost is approximately 20% of wired
Best Practices:
BEST PRACTICES:
4. Heat Trace Specialists
1. Qualifications / References / Experience
2. System Design capabilities (level of familiarity with
applications)
3. Audit and Recommendation Services
4. Turnkey Project Execution (as owner’s agent)
1.
Alignment of objectives
1.
2.
Collaborative vs. Adversarial
Plant Operations vs. “Get in – Get out” thought process
5. Maintenance and Repair (MI cable repair can save $$$)
6. Material Supply
TAKE AWAYS:
1. Freeze Protection Systems
• Audit – at least it’s a baseline and a “snapshot”
• Systems require maintenance:
•
•
•
Caulking dries out / Insulation gets wet / People use piping as “ladders”
Work on valves / pumps / instruments often leads to HT failures
Plan on failures - Budget for annual maintenance
2. Prioritize your systems and concentrate on what can hurt
you the fastest – spend your budget there!
3. Monitoring as much as possible – be alerted to an issue
before it’s a PROBLEM (24/7 vs. “snapshot)
Areas for Improvement / Discussion
1. Audit timing – Outage work on piping systems – Imperfect
world
2. Given the nature of why plants need “freeze protection”, how
does the cost justification model work for capital dollars
needed for Monitoring systems? What other productioncritical systems are Monitored and why?
Thanks for listening!
Tim Mullen
President
Diamond Thermal Systems