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GREA.T LAKES FILTER A MEMBER OF
THE ACME GROup
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Are Your Dust Collecting Techniques Gathering Dust?
I fyou·ve been using the same style dust collecting bags for many years, operating your dust collector could be costing much more than it should.
Here are five areas of concern where current technology can save you money the next time you change bags ...
L Reduce Energy Consumption: Proper fabric selection can lower pressure differentials reducing the cost of electricity per cubic foot of air.
2. Longer Bag Life: More durable fabrics can increase the length of time bags will function efficiently creating annual savings in bag costs and installation.
3. Lower Bag Cost: Replacement of existing fabric , felt or woven, with lower cost media having equal durability and filtration efficiency.
4. Less Installation Cost: Modern sealing and fastening devices can save time and labor of bag replacement. Assured fit and tensioning can lead to better filtration and longer bag life.
5 . Proper Conditions for Efficient Filtration: Assuming proper fabric selection, important factors influencing bag life are installation, maintenance, temperature regulation, and moisture control.
Frequently, multiple savings will result from prudent fabric selection.
Following are several examples of effective techniques for improved dust collector operation.
130
120
110
100
90
80
70
60
50
40
30
20
Reduce Energy Consumption
FILAMENT POLYESTER WARP KNIT VS. TWILL WEAVE
Warp Knit Twill Weave
Many collectors are presently equipped with all filament polyester twill weave fabric bags to overcome the difficulty of poor dust release. The key is t he use of filament yarns. Offsetting the improved dust release feature of this fabric are reduced bag life. insuff icient particle retention and relatively high energy consumption.
All three deficiencies can be overcome by using all filament yarn. warp knit fabric. This construction is considerably stronger in burst. tensile st rength and abrasion resistance. has better particle entrapment. less ai r resistance. and even better cake discharge. Your system can be operated at t he same air flow capacity with significantly less energy consumption.
FABRIC PERFORMANCE: ENERGY COSTS Based on $.062/kwh
V" ~
_......
---,.
/ 5 OZ POLYESTER TWILL
.1 .......
~ I,"
~i, -~., 1- .......
--I.- ._, II OZ POLYESTER WARP KNIT
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"""""" 50 70 90 110 130
S'l'SlEM CAPACITY (" IOO0CFM)
NOTE: This comparison relates to warp knit constructkms only . .. not to be confused with circular knits.
150
Reduce Energy Consumption
NEEDLED FELT VS. WOVEN POLYESTER
Possibly the most dramatic recent innovation in dust bag media is the development of needled felt especially designed to replace woven fabric in shaker clean collectors. This creates the opportunity to reduce energy cost per cubic foot of air. improve filtration efficiency and maintain bag life at no increase in bag cost.
• sW!' Shaker Applications
CONCLUSIONS OF COMPARATIVE STUDY
Fabrics:
Test Dust: Air to Cloth Ratio:
Dust Loading:
FILTERABILITY Woven:
Needled:
CLEANABILITY
10 oz. polyester felt with 1.8 oz. scrim reinforcement 9.1 oz. polyester sateen 0.5 micron silica 2.5 : 1 10 grains per ACF
Efficiency- 97.94% Pressure Drop 3.46 in. H20 Efficiency- 99.94% Pressure Drop 2.47 in. H20
Values determined after five cleaning cycles at two hour intervals Woven: Pressure Drop - Initial - 2.00 in. H20
Final - 4.92 in. H20 Needled: Pressure Drop- Initial- 1.70 in. H20
Final - 3.24 in. H20
DURABILITY Fatigue determined after 250,000 MIT flex cycles - Loss of tensile strength.
Woven: Warp-29.72% Filling - 29.86%
Needled: Warp - 29.69% Filling - 29.93%
Results taken from data compiled by Environmental Consulting Co. -Report TLN 5661. Complete report available on request.
,. 5.0 IN H,O
MICRO-FINISH@ FELT
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Section of unfinished felt showing needle hole ~f-~'~" ~- ; ij;i.._-,.-, , -~- . =---•-~~- .... ;;.... ~.:;. - ----~ -·.;-_c~~~~, ~,t~·,~:~~ ·-
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Section of comparable felt. micro-finish upper surface
Characteristic of an unfinished felt surface are geometrical discontinuities inherent in the needle felting process creating high air point velocities ... points at which dust is driven deeply into the felt where it is difficu lt to dislodge. This requires frequent pulsing and inhibits proper cake formation.
Great Lakes· Micro-Finish minimizes surface discontinuities and creates a surface sheen which promotes uniform cake formation and its easy discharge. Considerably lower pressure drops will be experienced reducing energy consumption along with less frequent cleaning cycles.
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2.o.t.---V~4---+-+--t---t--1-1
10--~.LJ~ - +--+--+--t--1---r--1
20 40 60 BO lOO 120 140 HOURS
THE BOTTOM LINE IS THE POWER LINE
Measuring energy consumption is no longer a mystery resolved on ly by the use of expensive inst rumentation. With an cMc nomograph and readily available ,,formation its easy to compute annua l
.:_)~•wer cost and determine the t?'.:'\?ct veness of various media. Havi ng s::1 ec:ed a more efficient medium. the - :- ce becomes that of either
--, man ng aT flow and reducing cash --:-\\ 2 1creasing air flow wh ile "e2:::- r; cashflow constant. Either way, : :_; es:: cost per cubic foot of air filtered.
POLYESTER VS. COTTON SATEEN
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4
Cotton
Comparative Taber Abrasion Wear After 1.448 Cycles
Reduce Energy Consumption
A c• C' D
12 _ii, 15 150.000 CFM
11 140,000
14
10 120,000
12
100.000
90,000
80,000
6 '
60.000
5'
50.000
40,000
3 ' 30.000
TO USE THE NOMOGRAPH THE FOLLOWING STEPS SHOULD BE TAKEN ,
1. DRAW LINE FROM A TO B.
2. DRAW LINE FROM C' PERPENDICULAR TO C'.
3. DRAW LINE FROM POINT ON C' TO DESIRED POWER COST ON LINE E.
4. READ ANNUAL FAN POWER COST ON LINED IN DOLLARS PER YEAR.
5. REPEAT PROCEDURE FOR COMPARISON.
Longer Bag Life
Cotton sateen was the standard of the industry for many years and is still widely used in shake collectors. However, the logical replacement in most applications is the equ ivalent polyester sateen fabric.
Comparative abrasion test results reveal the superior wear resistance of polyester; tensile, tear, and burst
COMPARISON OF PHYSICAL PROPERTIES Cotton Versus Polyester Sateen
15
13
11
S120,000 .035/KWH
90,000 ,033
.031
.029
.027
.025
.024
.023
.022
.021
.020
12.000 BASED ON,
10.000 55% EFFICIENCY FOR
8,000 FAN& MOTOR
6,000 8760 HOURS1YEAR
4.000
H = HOURS/YEAR
Q = C.F.M.
E = DOLLARS/KWH
2,000 SP = PRESSURE DROP
strengths are about double. Hence. life expectancy under identical operating conditions is two to three times as indicated by comparative test results.
Polyester also provides advantages of superior chemical resistance. low moisture absorption and higher temperature limitations when heat set.
Cotton Polyester
Weight - oz per sg. yd. 9.35 9.16
Yarn Count 97.2 X 60.8 97.0 X 61.8
Tensile - Lbs. 157 X 156 376 X 291
Elongation 12.6% X 13.8% 38.4% X 29.7%
Tongue Tear - Lbs. 13 X 13 24 X 27
Trae Tear - Lbs. 14 X 14 68 X 51
Permeabili~ - CFM 15.2 20.8
Mullen Burst - PSI 303 580
-
SATEEN VS. POLYESTER TWILL
Sateen Weave
PTFE, MEMBRANE VS. APPLIED FINISH
• • 0
0 0
00
0
• 0
•
Longer Bag Life & Lo~~r-Cost _ _ _ ________ _
A fabric still in use extensively is combination _(spun and filament yarns) polyester twill. The historical reasons for its use are no longer valid .
If it was installed for improved cake release. polyester warp knit will out perform it. But. more likely. it was
COMPARISON OF PHYSICAL PROPERTIES Polyester Sateen Versus Combination Twill
Yarns
Weight - oz. per sq. yd.
Yarn Count
Tensile - lbs.
Mullen Burst - PSI
Maximum Operating Temperature
Approximate Relative Cost
Lower Bag Cost
Not all the tough applications requ ire PTFE membranes now that a viable alternative exists.
chosen to replace cotton at slightly elevated temperatures. In that case a change to heat set. polyester sateen is recommended . You'll benefit from bags that last longer . filter better. and cost less.
Sateen Twill
All Spun Fil / Spun
9.16 6.54
97.0 X 61.8 79 X 80
376 X 291 322 X 243
580 385
275 F° 275 F°
100% 138%
POLYESTER FELT EFFICIENCY
STD PTFE PTFE
At one time membrane felt laminates were the only solution to critical filtration and difficult dust cake release situations. The economical alternative is PTFE surface finish on polyester or Nomex® felts which will clean and filter adequately in many of these applications. Quite likely you will experience lower pressure drops and less frequent cleaning cycles.
HOURS FELT FINISH MEM-
Comparative testing using 1 /2 micron silica dust reveal favorable results after a brief conditioning period.
BRANE
84.627% 97.441% 99.987%
2 86.931 98.536 99.999
5 88.472 99.218 99.999
7 94.873 99.923 99.999
14 95.918 ·99.946 99.999
To determine if it's right for your plant. try a set of bags or let us arrange a laboratory comparison with your dust. You 'll welcome the cost savings.
5
HI-TENA.CITY FELT
0
SINGLES VS. PLIED GLASS YARNS
SINGLES
PLIED
Fiber Glass Yarns
Lower Bag Cost & Energy Saving
Your felt bags will cost less with equivalent efficiency when made of Great Lakes Hi -Tenacity felt. Add to th is the potential for energy saving and you 'll pocket a tidy annual WINDFALL.
An advanced concept of fiber orientation achieves equal particle
retention with lower fabric weight. typically 12 oz. versus 16 oz. Test data using 1 /2 micron silica challenge dust reveal 92 - 95% efficiencies at 5:1 ai r to cloth ratios. Superior calendering propeties create more uniform. smoother surfaces for better cake release.
COMPARATIVE TEST RESULTS CONVENTIONAL VERSUS HI-TENACITY FELTS
Conventional Hi-Tenacity
Nominal Weight/Sq. Yd . 16 oz 16 oz 12 oz
Fiber Content Polyester Polypropylene
Rated C.F.M. 20-30 20-30 30-40 Finish None None None Max. Opeating Temp. 275 F" 200 F0 200 F0
Avg. Weight/Sq. Yd . 15.7 oz 15.8 oz 12.0 oz Thickness .061 in .080in .065in Avg. C.F.M. 22.9 25.0 36.1 Avg. Mullen Burst 460 PSI 550 PSI 440 PSI
CONCLUSION: At temperatures less than 200°F. Great Lakes Hi -Tenacity 12 oz felt will provide equivalent particle retention. lower pressure drop. lower cost per bag and similar bag life compared to conventional 16 oz felt.
At the same weight. 16 oz. and cost Hi -Tenacity felt will offer superior filtration efficiency and longer bag life under most conditions.
Lower Bag Cost & Longer Life
The premium cost of pl ied yarns in woven fiber glass fabrics is usually not necessary in filtration. Singles yarns create stronger, tighter fabrics ideal for high temperature. hot gas filtration. Where ultimate collection efficiency is required. such as cement. carbon black and lime, texturized filling yarns enhance particle retention.
COMPARISON OF PLIED VS. SINGLES YARNS 9.6 oz. 54 x 30 Count Fiberglass Gl-096 Acid Resistant Finish
Finish Content-%
Permeability---CFM
Mullen Burst...:..Psl
Tensile Strength LBS/IN Warp
Filling
Plied
4.4
70.4
213
131 93
Flexfold Cycles Warp 15440
Filling 221
Singles
4.0
65.0
448
202 110
26944 556
_ _ _ _ _____________ ______________________________ ,_
Less Installation Cost
BEADED SNAP RING QUICK, AIR TIGHT BAG SEAT
0 Get rid of those old thimbles or garter springs. Just make sure the tube sheet holes are true circ les and all the same diameter.
You can then equip you r bags with double beaded snap rings . . 3/4 ' or 1" wide stainless bands w ith upper and lower
gaskets to fit the tube sheet. made to + / - 1 /32" accuracy to prevent bypass.
Insta llation is easy. Simply collapse the bag bottom by squeezing opposite sides together. place in tube sheet and release. Removal is even easier. You ·II never own another thimble or double garter spring type again. Recommended for bag diameters of 4 to 6 inches.
TENSION SPRING AND CAP INSTALLATION
"'J"' Hook and Spring Assembly Old Style Strap Hanger
End the annoying task of tensioning each bag separately every time you change bags. Replace the conventional strap hangers in your bag house with spring loaded ·•J" hooks. These need only be adjusted once and they're set forever . The bags come w ith disposable caps instead of hanging straps which hook in place. ready to operate.
Bags wi ll clean better because they'll be fu lly open top to bottom. no restricting pleats. Increased usable cloth area. 7 - 10% more fi ltration area. wil l expand air flow capacity and extend bag life.
Proper Operating Conditions
Your collector is no better than its bags and the fabric they're made of. However . to achieve best resu lts. bags must be installed correctly and the equipment function ing properly. Several common problems that can impede performance are:
• Improper tensioning • Incorrect seating • Excessive air to cloth ratios • Sparks entering collector • Poorly timed cleaning frequency • Formation of excessive dust cake • Deficiencies causing worn bags • Excessive temperatures • Moisture in gas stream • Chemical attack of fabric or
sheet metal • Leaks in system
Providing the information called for in our questionnaire along with a " failed " bag wi ll set the stage for creative recommendations.
7
What's Best for Your Collector
OUR SPECIALISTS MAKE HOUSE CALLS
Though phone calls cost less and often suffice. frequently there's nothing better than a "house call " ... . bag house. that is. A hands-on learning experience will enable a specialist to cope with problems seldom unique to him. At the same time. he'll make a survey of all your bag houses and present a consolidated report. This will highlight operating conditions
and experience within a given plant providing comparative information which often leads to significant economies.
The familiar stance. "If it ain't broke. don't fix it" may be comfortable but not affordable.
FILTRATION SURVEY
APPLICATION COLLECTOR AN~MB~~NizE PRESENT MEDIA CLEANING
INDUSTRIAL FILTRATION APPLICATIONS Our Only Business
APPROXIMATE SERVICE LIFE
HL(. O MMENOATION
,111~= i,"FILTER
.-;;;;---.,,, ... , .... Ust~ BAG HOUSE MANUFACTURER
CLEANING METHOD (J SHAKER
Eou,..,..E..,. ~fating(
Tor Al NO BAGS 0 REVERSE AIR...__ --
AIR/CL ------- r J PULSE Jr-T 0TH RATIO NO COMPARTME c
MECHANICAL CO ---- AIR VOLUME ACFM NT$
NOITION -------- SCFM ------
APPLICATION
TEMPERATURE
CLEANING CYCLE
DIFF~~~!~~~~ESSUAE
NATURE OF ousr,_/
OPEAATJffQ CONornoNs
OPERATING ----FREQUENCY ---- -AFTER CLEA NING DURATION ---
PfAI(
---CHEMICAL CONDrTJONS
---- BEFORE CLEANING
LENGTH
PRESENT FABRIC
-8,\Q DESIQN & CONon-,
WIDTH OHS
--DIAMETER
PfAMEAarury BAG LIFE ------
- CFM_ FINISH ------
80TTOM
[) DUSTING
0 BURNING 0 HIGH DELTA ·p·
5151 lora,ne • D
{800) s21.e56s ,u;: ;,1, ':'c~,~J • f J t JJ 89◄-1950 556-9129 (MICH) ----
The same thoughtfu l procedure to select the best possible dust bags obtains for all types of dry and liquid filtration. Great Lakes commitment to excellence is uncompromised in any of these product lines. whether our own make or manufactured for us for distribution.
With virtually every type of industrial filter available. our only constraint is what's best for your application.
AC DELCO-Vehicle Filters ALSOP ENGINEERING-Pads & Housings AIR MAZE-Filters and Air/ Oil Separators FILTERITE- Vessels. Cartridges, and Membranes FLUID DYNAMICS-Metallic Elements FLUITEK-Replacement Elements KOCH-Air Filtration U F STRAINRITE-Vessels and Bags HVAC Filters Coolant Media Die Cut Filter Media Filter Presses, Cloth, Paper. and Pads Flat Bed Filters Oil Reclamation Systems Oil/Water Coalescer Separators Sand Filters Strainers and Screens Waste Water Treatment Systems
REt..TlAKES FIi 'JER A MEMBER OF I. THE ACME GROUP
5151 Loraine Detroit. Michigan 48208 Telephone (313) 894-1950 Toll Free (800) 521 -8565. U.S. (800) 556-9129 Mich.
Supporting data from independent testing laboratories available to confirm technical information in this report.