WMRC Reports
Waste Management and Research Center
Effect of Barrel Design On Dragout Rate
CMFI The Chicago Metal Finishers Institute
RR-95 July 2002 Electronic Version
About WMRCs Electronic Publications:
This document was originally published in a traditional format. It has been transferred to an electronic format to allow faster and broader access to important information and data. While the Center makes every effort to maintain a level of quality during the transfer from print to digital format, it is possible that minor formatting and typographical inconsistencies will still exist in this document. Additionally, due to the constraints of the electronic format chosen, page numbering will vary slightly from the original document. The original, printed version of this document may still be available. Please contact WMRC for more information:
WMRC One E. Hazelwood Drive Champaign, IL 61820 217-333-8940 (phone) www.wmrc.uiuc.edu
WMRC is a division of the Illinois Department of Natural Resources
Identification of barrels evaluated in this study: #1 Tscherwitschke Galvanet - Series 03/18 #2 Stutz Company - Model 2000 #3 Sterling - Model B612K #4 Hardwood Line Mesh Barrel - Model # not available #5 Northwestern - No barrel identification #6 Tscherwitschke - Galva E #7 B & P Plating Supply Basket Plater - Model 2X18 #8 Hardwood Line Slotted Barrel
CMFI Chicago Metal Finishers Institute Chicago, Illinois

July 2002

Submitted to The Illinois Waste Management and Research Center One E. Hazelwood Dr. Champaign, IL 61820 www.wmrc.uiuc.edu
Printed by the Authority of the State of Illinois 2002/50
This report is part of WMRCs Research Report Series. Mention of trade names or commercial products does not constitute endorsement or recommendation for use.

ACKNOWLEDGMENTS

The authors would like to thank the following for their assistance, patience and guidance as we conducted this study: Northwestern Plating Works, Mr. David Jacobs, President Artistic Plating Company, Mr. John Lindstedt, President The Stutz Company, Mr. Gerry Stutz Sterling Systems, Mr. Jerome D. Schultz, President B&P Plating Supplies, Mr. Ron Landrette. General Manager Reinewald Plating Company, Mr. Ted Reinewald, President Reliable Plating Corporation, Mr. Jim Greenwell, President The Chicago Metal Finishing Institute, Mr. Bill Suzuki, President and Ms. Evelyn Hallberg, Secretary Chris Hayes, Pollution Prevention Technical Assistant, WMRC Tim Lindsey, Manager, Pollution Prevention Programs, WMRC Nandakishore Rajagopalan, Sr. Research Engineer, WMRC
TABLE OF CONTENTS Page Number Acknowledgments Table of Contents List Tables List of Figures Abstract Executive Summary Body of Report Introductory Material Methodology Results Discussion Conclusions Recommendations References Appendices Appendix A: Dragout Data/Graphs/Figur es Appendix B: Photographs of Tested Barrels A.A.1-A.A.24 A.B.1-A.B.iii iv v vi vii viii
LIST OF TABLES Page Table 1: Dragout Rates Measured from Various Barrel Types Table 2: Summary of Questionnaire Responses Regarding Barrel Toughness 8 9
LIST OF FIGURES Figure Figure A-1 Figure A-2 Figure A-3 Figure A-4 Figure A-5 Figure A-6 Figure A-7 Figure A-8 Figure A-9 Figure A-10 Figure A-11 Figure A-12 Figure A-13 Figure A-14 Figure A-15 Figure A-16 Figure A-17 Figure A-18 Figure A-19 Figure A-20 Figure A-21 Figure A-22 Figure A-23 Figure A-24 Figure C-1 Figure C-2 Figure C-3 Figure C-4 Figure C-5 Figure C-6 Figure C-7 Figure C-8 Figure C-9 Figure C-10 Figure C-11 Figure C-12 Figure C-13 Figure C-14 Figure C-15 Figure C-16 Figure C-17 Figure C-18 Title Graphed Raw Dragout Data - Barrel Design 1 - Trial 1 Graphed Raw Dragout Data - Barrel Design 1 - Trial 2 Graphed Raw Dragout Data - Barrel Design 1 - Trial 3 Graphed Raw Dragout Data - Barrel Design 2 - Trial 1 Graphed Raw Dragout Data - Barrel Design 2 - Trial 2 Graphed Raw Dragout Data - Barrel Design 2 - Trial 3 Graphed Raw Dragout Data - Barrel Design 3 - Trial 1 Graphed Raw Dragout Data - Barrel Design 3 - Trial 2 Graphed Raw Dragout Data - Barrel Design 3 - Trial 3 Graphed Raw Dragout Data - Barrel Design 4 - Trial 1 Graphed Raw Dragout Data - Barrel Design 4 - Trial 2 Graphed Raw Dragout Data - Barrel Design 4 - Trial 3 Graphed Raw Dragout Data - Barrel Design 5 - Trial 1 Graphed Raw Dragout Data - Barrel Design 5 - Trial 2 Graphed Raw Dragout Data - Barrel Design 5 - Trial 3 Graphed Raw Dragout Data - Barrel Design 6 - Trial 1 Graphed Raw Dragout Data - Barrel Design 6 - Trial 2 Graphed Raw Dragout Data - Barrel Design 6 - Trial 3 Graphed Raw Dragout Data - Barrel Design 7 - Trial 1 Graphed Raw Dragout Data - Barrel Design 7 - Trial 2 Graphed Raw Dragout Data - Barrel Design 7 - Trial 3 Graphed Raw Dragout Data - Barrel Design 8 - Trial 1 Graphed Raw Dragout Data - Barrel Design 8 - Trial 2 Graphed Raw Dragout Data - Barrel Design 8 - Trial 3 Barrel Design 1 Barrel Design 1 - Hole Design Barrel Design 1 - Drive Shaft Barrel Design 2 Barrel Design 2 - Hole Design Barrel Design 3 Barrel Design 3 - Hole Design Barrel Design 3 - Gear Dragout Barrel Design 4 Barrel Design 4 - Hole Design Barrel Design 5 Barrel Design 5 - Hole Design Barrel Design 6 Barrel Design 6 - Hole Design Barrel Design 7 Barrel Design 8 Barrel Design 8 - Hole Design Fasteners Used In Test Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page A-A-1 A-A-2 A-A-3 A-A-4 A-A-5 A-A-6 A-A-7 A-A-8 A-A-9 A-A-10 A-A11 A-A-12 A-A-13 A-A-14 A-A-15 A-A-16 A-A-17 A-A-18 A-A-19 A-A-20 A-A-21 A-A-22 A-A-23 A-A-24 A-B-1 A-B-1 A-B-2 A-B-3 A-B-3 A-B-4 A-B-4 A-B-5 A-B-6 A-B-6 A-B-7 A-B-7 A-B-8 A-B-8 A-B-9 A-B-10 A-B-10 A-B-11

ABSTRACT

New barrels for electroplating have been developed and manufacturers of some of these newer designs have claimed significant improvements in drag-out losses by their new barrels. Since water consumption and waste generation are directly tied to dragout rate from processing solutions, it is clear that there is a need to produce a method of evaluating such barrels, so that the user minimizes pollution. This study, funded by The Illinois Waste Management Research Center (WMRC) produced a benchmark test to compare drag-out rates of plating barrels. The study used this test to compare two size ranges of plating barrels, small and large. For small barrels (6 x 12), testing showed that a reduction in dragout rate, as high as 48%, may be achieved. For large barrels (16 x 36), testing showed that a reduction as high as 44% may be obtained. A survey was conducted to determine the relative durability of the barrels under study. The survey indicated that some of the barrels that produce lower levels of dragout (those using fine mesh) may unfortunately provide less service life, but other low dragout rate barrels offered service life that is similar to traditional barrels.

EXECUTIVE SUMMARY

Metal finishing operations typically process large numbers of small parts such as rivets and fasteners in perforated cylindrical barrels for operations such as electroplating, electropolishing, phosphating, black oxiding, and several other coating operations. Because this type of processing produces large volumes of entrapped liquid (called dragout), it is a major source of waste, as the dragout typically is waste treated yielding F-006 hazardous waste in many cases. Further, the dragout chemical must be rinsed during the processing steps and the volume rate of rinsewater is directly related to dragout rate. As an example, for an ideal single rinse, the rinsewater flow necessary to achieve a specific purity of rinse is determined by the equation: F = D (C t /Cr), where F is the rinse flow rate, D is the dragout rate and Ct/Cr is the rinse ratio (concentration of contaminant in the process tank divided by the concentration of the same contaminant in the rinse tank). Therefore, reduction of dragout from barrel processing operations prevent pollution in several ways: 1. Reduces water consumption 2. Reduces hazardous waste generation 3. Reduces operating costs by saving chemicals purchased The Illinois Waste Management Research Center agreed to fund a study that would produce a benchmark test to compare drag-out rates of plating barrels. We used this test to compare a small sample of barrel designs, in order to illustrate the efficacy of the test and provide the metal finishing industry with guidance that can be used to reduce dragout rates, making it easier to achieve their goals under SGI. The information can also be used by equipment manufacturers to improve the designs of their plating barrels, so that lower levels of dragout rates can result in lower levels of pollution on a nation-wide basis. The study was limited to two size ranges of plating barrels, small and large. For small barrels (6 x 12), testing showed that a reduction in dragout rate, as high as 48%, can be achieved by replacing commonly used existing barrels constructed of solid walls and drilled holes with newer designs that incorporate meshed material into the walls of the barrel. The results obtained were: Summary of Dragout Rates-Small Barrels Lowest Dragout Rate 142.2 mL, 23.7 mL/lb. of parts Highest Dragout Rate 270.8 mL, 45.1 mL/lb. of parts Average of 4 Barrels 200.35 mL, 33.4 mL/lb. of parts

For large barrels (16 x 36), testing showed that a reduction as high as 44% can be obtained. The barrels yielding the best results included one design that utilizes portable oblique rotating baskets as opposed to the commonly used plastic walls perforated with drilled holes. The other well performing design utilized slots instead of drilled holes, and this design yielded the best over-all results for large barrels. Test data generated showed: Summary of Dragout Rates-Large Barrels Lowest Dragout Rate 1670 mL, 11.2 mL/lb. of parts Highest Dragout rate 3881 mL, 25.9 mL/lb. of parts Average of 4 Barrels 2400 mL, 16.3 mL/lb. of parts
The average dragout rates can be used as a benchmark by metal finishers in evaluating their own equipment. Barrels that dragout less than the average can be considered to be pollution prevention friendly. A survey was conducted to determine the relative durability of the barrels under study. The survey indicated that some of the barrels that produce lower levels of dragout may unfortunately provide less service life. These types of barrels typically utilize a fine mesh for part of the barrel wall. Responses from metal finishers using barrels with fine meshed sides indicate tha t they last only about 33% as long on average as other barrels with polypropylene sides with holes/slots etc. Barrels with larger, reinforced mesh appeared to yield service life along the same level as traditional barrels. Other failures commonly mentio ned include gear failure. Alternate drive methods (belts for example) or better gear design appear to be desirable design features. The newest barrel designs yielding the lowest dragout rates were too new to yield extensive service information. The slo tted barrels and portable oblique basket plater were in use only for about 1 year without indication of any deterioration. This study yielded the following: 1. We have developed a procedure for benchmarking barrels used in various metal finishing operatio ns. This procedure is relatively easy to conduct and can be conducted by any metal finisher at reasonable effort and cost. 2. We have demonstrated that there is a significant difference in dragout rate produced by different barrel designs, with newer designs reducing dragout rate almost 50%. Our results compare favorably with those reported by one barrel manufacturer4 who indicated that 26 to 49% reduction in dragout rate can be achieved by changing from a traditional barrel with drilled holes to one with a mesh pattern.
3. We have surveyed barrel users and found in general that barrels offer a long service life, with a possible exception to barrels that utilize a fine mesh as part of their wall design.

Using this study any metal finisher utilizing traditional barrels can evaluate the economics of changing over to one of the newer designs incorporating either a mesh pattern or slots and can significantly reduce pollution. Any metal finisher can also determine if his existing barrel equipment matches the performance of the newer designs. Additional work that would be highly desirable is: 1. We would like to replace the conventional barrels at the metal finisher that allowed us to conduct this study with one of the newer designs and then obtain real- life dragout loss data, along with data on the ruggedness, plating efficiency differences (if any) and service life of the barrel. 2. We would like to have the opportunity to test barrels of other sizes and designs to yield a more complete guide for the metal finisher.

INTRODUCTORY MATERIAL

Barrel plating pre-dates the past century and is not significantly different today, in that a rotating cylinder with perforations for the purpose of allowing transfer of DC current and processing solution is still used today. However, there have been significant improvement claims in the technology of barrel plating, especially in the area of lowering dragout rates and improving barrel plating efficiencies. The American Electroplaters and Surface Finishers Society (AESF, Orlando FL) conducted a research project (AESF Research Project 34) on the Theory of Metal Distribution in Barrel Plating2 , but this study did not cover barrel designs. AESF Research Project 44 studied the optimization of barrel zinc plating solutions1. Stein, Te ichman and Thompson4 compared vibratory plating equipment with barrel plating equipment for nickel plating of small parts, and concluded that barrel plating was more suitable than vibratory systems for nickel plating of small batches of small sized parts. More recently, LaVine3 reported on a new barrel design incorporating a staggered cells and meshed walls to improve solution transfer and lower drag out rates. LaVine reported the new design could reduce dragout rates in nickel plating solutions by 26-49%, when compared to two traditional barrel designs. No details of the method of evaluations are given. Tremmel5 mentions tapered slots as part of a continuous plating system that is designed to replace conventional barrel plating equipment. Additio nal manufacturers lay claim to reduced dragout rates6. None of the above literature in our background search compared various barrel designs under identical conditions to yield comparative dragout rates and relate results to design parameters and barrel service life. The purpose of this study was to accomplish such a goal. Barrel electroplating is commonly known to present a higher degree of trouble in recyclerecovery schemes and in wastewater treatment operations due to the high dragout rates during barrel processing. The high dragout rates are caused by a combination of high surface area loads and retained liquid on the barrel and superstructure. While little can be done about the part loading/surface area in any given barrel plating operation, there have been revised barrel designs that may result in lower dragout rates. Complicating the issue of barrel design vs. dragout reduction is the possibility that a given design may reduce dragout rate, but will not provide long term service, as some of these designs utilize thin- wall construction, that may fracture over the life of the barrel, reducing productivity and decreasing the acceptability of alternate barrel designs by the industry. This study intended to determine: a. If significant reductions in dragout can be achieved by replacing an existing barrel with a newer design. b. If the newer design barrels offer similar barrel service life (when compared to conventional barrel designs).

The study was funded and conducted under the WMRC ADOP2 T program which assists industry members in achieving goals in pollution prevention. The study was further sponsored by an individual metal finishing job shop, Northwestern Plating Works, located at 3136 S. Kolin Ave. Chicago IL 60623. Mr. David Jacobs, President allowed us to utilize an actual barrel plating line to conduct our experiments, and provided us with an example of a traditional plating barrel that we could use in our study. Letters of invitation were sent to all barrel manufacturers listed in Metal Finishing Guidebook and Directory. Of eight requests, three barrel manufacturers volunteered to supply us with barrels to include in the study (a fourth, Whyco Technologies also volunteered, but was not included due to miscommunication between the sponsor plating company and Whyco). Also, Artistic Plating Company, Milwaukee WI, Mr. John Lindstedt, President; Reinewald Plating Company, Chicago IL, Mr. Ted Reinewald, President ; and The Stutz Company, Mr. Gerry Stutz, added additional barrels for testing. The intent of our study was not to create a competition between barrel manufacturers to see who could lay claim to the lowest dragout rate and therefore we do not identify which company manufactured which barrel. This study had three goals: 1. Relate performance in dragout reduction (or lack thereof) to specific design parameters, so that future barrel designs might incorporate the better ideas. 2. Provide guidance to metal finishers as to barrel designs that would allow them to reduce dragout rates. 3. Begin the establishment of a benchmarking system that could be used to determine if a metal finisher was using barrel plating equipment that was above average in reducing pollution loading.
Equipment Descriptions A total of eight (8) different plating barrels were evaluated in this study. To keep the comparisons as fair as possible, we separated the barrels into two size groups. Of the eight barrels evaluated, four were small barrels (six inch diameter) and four were large barrels (14 to 16 inch diameters). The following are descriptions of each barrel tested, any unique features in the barrel that may affect dragout, and the estimated cost of the barrel.

1. Small Barrels Evaluated Barrel Design-1 (See Figure C-1) Description of Barrel: Barrel one is a 6 x 12 hexagonal plating barrel with replaceable mesh sides. Mesh sides have slots measuring 0.010 x 0.150 with approximately 384 slots per panel and 6 panels per side (See Figure C-2). Slots are tapered slightly and are larger on the outside of the barrel than on the inside. Unique Feature(s): Vertical Drive Shaft (See Figure C-3), Replaceable Mesh Side Panels, Variable Speed Drive System Approximate Cost: $1,000 (as shown) $ 550 (Cylinder, gears only)
Barrel Design-2 (See Figure C-4) Description of Barrel Barrel is a 6 x 12 round corrugated plating barrel with round holes. Holes are 3/32 in diameter and there are approximately 36 holes per square inch. The corrugated barrel provides more holes for drainage than a standard round barrel with the same dimensions. Unique Feature(s) Corrugated sidewalls (See Figure C-5), Gear driven on only one side. Approximate Cost: $1300 $ 510 (Cylinder, gears only)
Barrel Design-3 (See Figure C-6) Description of Barrel Barrel is a 6 x 12 octagonal plating barrel. The sides of the barrel are ribbed on the outside and have holes between the ribs. This barrel has square holes 0.100 x 0.100 with approximately 30 holes per square inch. (See Figure C-7) Unique Feature(s) Ribbed walls increase strength while allowing areas with holes to be made thin. The barrel is gear-driven on both sides for better distribution of torque. However, the teeth on the gears are a large source of dragout (See Figure C-8). Square holes help break surface tension of solutions to allow better drainage. Approximate Cost: $1200 $ 600 (Cylinder, gears only)
Barrel Design-4 (See Figure C-9) Description of Barrel Barrel is a 6 x 12 round plating barrel with a finely woven mesh sides. The sides of the barrel are ribbed and covered in a woven plastic mesh (See Figure C-10). This barrel is gear driven on one end but the drive mechanism can be placed on either end of the barrel. Unique Feature(s) Woven mesh sides will retain all sizes of parts. The ribbed sides provide added strength. The barrel is gear-driven on only one side. Approximate Cost $1200 $ 650 (Cylinder, gears only)
2. Large Barrels Evaluated Barrel Design-5 (See Figure C-11) Description of Barrel Barrel is a 16 x 36 hexagona l plating barrel. This barrel has round holes and has approximately 695 holes per side. It is mounted on a frame and is belt driven. Unique Feature(s) The barrel is belt driven providing less surface area than a gear driven barrel (See Figure C-12). Approximate Cost: $2250 $1500 (Cylinder, gears only)
Barrel Design-6 (See Figure C-13) Description of Barrel Barrel is a 14 x 36 hexagonal, belt driven plating barrel. This barrel has a unique hole design consisting of 3/32 round holes on the outside of the barrel with 0.220 square on the inside of the barrel walls tapered to the round external holes (See Figure C-14). There are approximately 16 holes per square inch. Unique Feature(s) A square-to-round hole design funnels the solution out of the barrel. The belt driven design reduces overall surface area. Approximate Cost: $2000 $1300 (Cylinder, gears only)

Barrel Design-7 (See Figure C-15) Description of Barrel The barrel is a portable oblique plater designed to replace 16 x 36 horizontal plating barrels. This barrel has two (2) rotating baskets with 3/16 diameter round holes. There are approximately 10 holes per square inch. The baskets are set at an angle of about 45o. Unique Feature(s) It is easier to load and unload manua lly or on an automated basis (no door) and different baskets can be used in same frame improving versatility. Approximate Cost $2,000
Barrel Design-8 (See Figure C-16)) Description of Barrel Barrel eight is a 14 x 36 hexagonal, gear driven plating barrel. This barrel has staggered 0.16 x 1.0 and 0.16 x 0.5 slots (See Figure C-17). There are approximately 572 slots per side. Unique Feature(s) It utilizes slots instead of holes. The irregular shape of slots prevents liquid from staying in opening. Approximate Cost: $2400 (Cylinder, gears only)

METHODOLOGY

This section will discuss the methodologies used to determine dragout from the different barrels and barrel toughness. Dragout evaluation The following equipment was used and conditions adhered to during the dragout evaluation: A. Single process tank made of polypropylene B. Single static rinse tank C. Manual barrel handling D. Process solution contained only metal salt (copper sulfate), acid and water (no rinse aid) E. Measured the increase in metal ion concentration in the rinse tank after each barrel load rinse F. Barrels from volunteer manufacturers or metal finishers Process Solution: The dragout evaluation was performed using a solution of copper sulfate, sulfuric acid and water. These ingredients were chosen to keep the process solution as simple and free of additional
variables (such as wetters) as possible. This also allows an individual metal finisher to duplicate our experiment with his own equipment in order to compare his performance with the equipment tested here. The initial copper concentration in the copper sulfate solution ranged from 117.00 ppm to 846.00 ppm and is relatively unimportant to the results obtained, as long as the concentration of copper can be reliably measured in the rinse. Comparative tests conducted by others should use solutions of similar concentrations to minimize viscosity effects (from concentration differences). Process Parts: Plating barrels tested were charged with 6 pounds of assorted stainless steel fasteners for the small barrels and 150 pounds of assorted stainless steel fasteners in the large barrels. The fasteners used were an equal mixture by weight of: 3/8 tapered hex washer head screws, 1 flat head Phillips screws and 1 slotted head cap screws (See Figure C-18). The exact same load of fasteners was used for each barrel evaluation. A total of three (3) trials were performed on each plating barrel tested. Each trial was conducted according to the following steps: a) The copper sulfate solution was made up containing 117.00 to 846.00 ppm of copper. b) A second tank used to simulate a dead rinse was filled with tap water. c) A sample was collected from each tank prior to starting the test. d) The plating barrel to be tested was loaded with the proper amount of parts and then lowered into the copper sulfate solution. e) The barrel was rotated in the solution for thirty seconds and then removed from the tank. f) After being removed from the copper sulfate solution tank, the barrel was rotated 1- revolutions, stopped, and then allowed to drain for a total time of thirty seconds above the process tank. g) The plating barrel was then lowered into the rinse water and rotated for thirty seconds. h) The plating barrel was then removed from the rinse tank, rotated 1- revolutions above the rinse tank, and then allowed to drain for thirty seconds. i) After mixing the water in the rinse tank manually, a sample of the rinse tank was collected for use in determining the amount of dragout. j) Steps e through i were then repeated nine more times to conclude the trial.

Barrel Number Small Barrels 1
Large Barrels 29862 /12852 /1670 15.3 16.7 14.0 15.3 19.4 19.6 20.7 19.9/25.9 12.6 10.9 11.5 11.7 9.3 8.9 7.5 8./11.2
*Each individual trial result is an average of the ten individual runs conducted in each trial
1 The dragout results for Barrel 7 were based on the first seven runs only. Runs 8, 9, and 10 in all three trials were erratic and significantly higher than the first seven runs. Including Runs 8, 9, and 10, the average dragout for Barrel7 would be 4800 mLs. 2 The dragout results for Barrels 6 and 8 are based upon testing a 14 x 36 barrel, while the others are 16 x 36. Second set of numbers are adjusted by a factor of 1.3 to compensate for size difference.
Barrel Toughness Results The following is a summary of the completed questionnaires received from polling barrel electroplaters regarding barrel toughness:
Table 2: Summary of Questionnaire Responses Regarding Barrel Toughness
Barrel Type Round Barrel with Round Holes Hexagonal Barrel with Fine Mesh Hexagonal Barrel with Large Mesh Hexagonal Barrel with Square Holes Tapering to Round Basket Plater with Round Holes

Number of Responses 12

Range of Average Life Average of Barrel Life of Barrel from Responses 2-10 years 6.5 Years
Most Common Cause of Failures Gears Fail and Holes Enlarge Mesh Failure

1-12 years

4.5 Years

10-12 Years

11 Years

Mesh Failure

12 Years

Polypropylene Failure

Unknown
Barrel is only 1 year old
Hexagonal Barrel with Small Round Holes Hexagonal Barrel with Large Round Holes Hexagonal Barrel with Tapered Holes Hexagonal Barrel with Slots Hexagonal Barrel with Round Countersunk Holes

Years 12 Years

Gears Fail, Panels Split

Years 11 Years

5 Years
Aging of Polypropylene Barrel is only 1 year old

Holes Close Panels Split

RESULT SUMMARY
Summary of Dragout Rates-Small Barrels Lowest Dragout Rate 142.2 mL, 23.7 mL/lb. of parts Highest Dragout rate 270.8 mL, 45.1 mL/lb. of parts Average of 4 Barrels 200.35 mL, 33.4 mL/lb. of parts Testing showed that a significant reduction in dragout rate can be achieved by replacing older design barrels with newer designs. A reduction as high as 48% may be obtained. Summary of Dragout Rates-Large Barrels Lowest Dragout Rate 1670 mL, 11.18 mL/lb of parts* Highest Dragout Rate 3881 mL, 25.9 mL/lb. of parts* Average of 4 Barrels 2079 mL, 13.9 mL/lb. of parts Testing showed that a significant reduction in dragout rate can be achieved by replacing older design barrels with newer designs. A reduction as high as 44% may be obtained*. * This barrel was 14 x 36 vs. while the others were 16 x 36 (we were unable to obtain a 16 x 36 slotted barrel, as the manufacturer declined participation in this study). We have adjusted by the difference in area of a solid 14 x 36 cylinder vs a solid 16 x 36 cylinder (a factor of 1.3) the adjusted dragout rate of this barrel is as shown. The actual results obtained with the smaller barrel are shown in Table 2.

DISCUSSION

Small Barrel Dragout Results A plater using a plating barrel of similar size to those we evaluated should expect a dragout rate of less than 200 mL (33.4 mL/lb. of parts) when tested as described in this report for above average levels of pollution prevention. Barrel 1: This performed very well in the dragout evaluation, dragging out an average of 147 ml per cycle. The low dragout rate may be attributed to several design features: 1) A vertical drive shaft that reduces the size of the gear and consequently, the number of teeth on the gear (See Figure C-3). 2) A very narrow side frame (approximately 7.5 inches compared to 10 inches for the other small barrels we evaluated).
3) Unique gear positioning (See Figure C-3). We noticed that the more traditional gears tended to trap liquid between gear teeth. 4) This barrel had a gear on only one side as compared to the others (gears on both sides).
All four of these design features reduced the amount of surface area of the barrel that comes in contact with the plating solution, thus reducing the amount of wetted area of the barrel and the amount of solution dragged out by the barrel itself. The low dragout rate of Barrel 1 may also be attributed to the fact that the openings in the barrel are slots (See Figure C-2). As discovered while evaluating the large barrels, slots seem to be more efficient in draining solution than holes. Some barrel manufacturers claim that round holes tend to generate equal wall pressure and surface tension that causes the liquid to be entrapped within the holes. Barrel 2: This barrel produced 270.8 mL (45.1 mL/lb. of parts) of drag out rate, yielding results that were significantly above the average of the four barrels. The higher dragout rate may be attributed to the fact that this barrel had two, large gears that entrapped a significant amount of liquid (See Figure C-8). Also, the side frames were significantly wider than on Barrel 1 (10 x 10 vs. 7 x 10). This barrel had an estimated 60 square inches more of surface area contacting the solution than Barrel 1. Barrel 3: This barrel produced 241.4 mL (40.2 mL/lb. of parts) of dragout rate, yielding results that were significantly above the average of the four barrels. The higher dragout rate may be attributed to the fact that this barrel had two, large gears that entrapped a significant amount of liquid (See Figure C-8). Also, the side frames were significantly wider than on Barrel 1 (10 x 10 vs. 7 x 10). This barrel had an estimated 60 square inches more of surface area contacting the solution than Barrel 1. Also, Barrel 2 was corrugated (See Figure C-5). Some think that the corrugated sides allow for an increased number of holes, thus, increasing drainage efficiency. The test data indicate otherwise. Barrel 4: This barrel yielded dragout losses similar to Barrel 1, dragging out and average of 142 mL per use. This barrel had the identical frame and gears as Barrels 2 and 3. However, the barrel itself was constructed of a very fine, replaceable, woven mesh. Even with similar areas or wetted surface due to the large frame and the two large gears, this barrel outperformed drilled holes.

Economics-Small Barrels The sponsor plating company for this project does not use barrels of this size. A metal finisher that uses such small barrels can consider the following options: Option 1 Replacing Barrels En Masse: A newer design barrel costs about $1200.00 and saves about 140 mL of processing solution in each process step (soak clean, electroclean, acid dip, electroplate, post plate dip) per run. Assuming 1,000 runs per barrel per year, and 5 processing steps, a total of 185 gallons of processing solution would be saved annually. The value of the processing solution saved, plus labor to make up the solution, cost of chemicals for waste treatment, and cost of disposal of hazardous waste would need to be $3.24/gallon for a two- year payback. Option 2 Replacing Barrels As They Are Consumed: Since there is either no cost difference between the newer slotted barrels and traditional designs, or because mesh wall barrels may actually be lower in cost than traditional units, it appears that instant cost savings can be realized by replacing traditional barrel designs with one of the newer ones (mesh wall or slotted), as the need to replace a barrel arises. The mesh walled barrels should be carefully evaluated for wall life. The mesh walled barrel design we tested was actually 20-30% lower in cost vs. traditional designs and allowed for easy replacement of the mesh. Large Barrel Dragout Results Barrel Number 5 (traditional design): This barrel was in use by the sponsor plating company. The dragout loss per barrel was almost 2300 mL (15.3 mL/lb of parts); which was below the average performance for the four barrels tested. Barrel Number 6 (the square to round holes): This barrel was only 14 x 36, yet it yielded the highest level of dragout in this evaluation, dragging out 2986 mL per cycle. If corrected for surface area (factor 1.3) to allow for a more accurate comparison with the 16 x 36 barrels, the dragout rate would be 3881 mL (25.87 mL/lb. of parts). In fairness, the holes in this barrel were too small for the parts that were plated. Larger holes would have been usable and would have resulted in better performance. If anything, the data reported confirm the importance of matching hole size to part size to reduce dragout and improve plating efficiency (a task often ignored by metal finishers). Barrel 7 (the portable oblique barrel): Test results for this barrel were based on only the first seven runs of the trial. Runs 8, 9, and 10 in all three trials showed significantly more dragout than the Runs 1-7 and the results, for unexplained reasons were highly erratic (see graphs in appendix). We have therefore used the data from only the first 7 runs in each trial, but include all our data in the appendix. Further investigation into the erratic results towards the end of each run is warranted, especially in light of the modified results being the second best over-all performance in dragout reduction. When the last three runs in each trail are deleted, this equipment yields similar results to the slotted barrel (after the slotted barrel results are adjusted for size differences).

The portable oblique plater yields lower levels of dragout because each basket has a curved wall that acts much like a funnel channeling trapped solution to a low-point in the curved basket wall where hydraulic pressure tends to build up, forcing more liquid through the holes than if the walls were horizontal as in a conventional barrel. Barrel-8 (slotted holes barrel): This was the best performing large barrel in our study, dragging out 1285 mL, 8.6 mL/lb. of parts (1670 mL, 11.2 mL/lb. of parts when adjusted for size difference). Although the dwell time of each barrels evaluated was 30 seconds, test personnel noticed a significant difference in drain time. Water tended to gush out of this barrel in noticeably less time. Economics-Large Barrels The sponsor plating company for this project turns over approximately nine barrels per hour or approximately 18,720 barrels per year in a nine (9) station plating tank. Since the slotted barrel drags out approximately 0.6 liters per cycle less than their current barrels (slotted barrel results adjusted to simulate a 16 diameter barrel), the pilot plating company would save approximately 3100 gallons each of soak cleaner, electrocleaner, acid and electroplating solution each year. The metal finisher would have at least two options: Option 1-Replacing All Barrels At One Time: Nine replacement slotted barrels would cost an estimated $21,600.00. Nine replacement portable oblique plating systems would cost about $18,000.00. For a two-year payback, the total sum value of the processing solutions plus labor costs to produce the solutions, plus waste treatment and disposal of hazardous waste would need to be $3.32/3.48 per gallon for the portable oblique system and slotted barrel, respectively, which is below the cost/value of most barrel plating solutions used in metal finishing. Based on the dragout evaluation results, the pilot plating company would save approximately 2700 gallons of process solutions per year using the portable oblique system versus the current plating barrel. Option-2 Replacing Barrels As They Are Consumed: In this option the metal finisher would replace barrels that are damaged beyond repair with one of the new designs. The cost basis would then be the difference between the cost of the new design vs. a traditional barrel. For the slotted barrel, the difference in cost is approximately $900.00. If one of the nine barrels is replaced with the new design, it would save 344 gallons of processing solution per year. The total value of the saved processing solutions would need to be $1.31 per gallon for a two year payback on the difference in cost between the two barrel designs. For the portable oblique barrel, the difference in cost is $500.00 (cost of replacement of cylinder and gear for traditional barrel vs. cost of entire portable oblique barrel system). The total value
of the processing solutions would then need to be $0.83 per gallon or less for a two-year payback. A metal finisher replacing only a portion of a set of barrels may be faced with varying plating efficiencies between the newer designs (tend to be higher in plating efficiency) and older designs. On manual lines, adjustments may be possible (the plater can remove the more efficient barrel sooner), but on automated lines, it would most probably be best to replace all barrels at one time. The additional benefit of higher productivity with the new barrel designs was not part of this study and has therefore not been included in our economic analysis. Discussion of Survey Results Responses from metal finishers using barrels with fine meshed sides indicate that they last only about 33% as long on average as other barrels with polypropylene sides with holes/slots etc. Barrels with larger/reinforced mesh appeared to yield service life along the same level as traditional barrels. Service on fine meshed barrels was reported at an average of 4.5 years by 5 users, with the shortest level of service at 1 year and the longest at 12. Large meshed and conventional barrels (horizontal cylinder with drilled holes) yielded a service life range of 5-25 years, with an average of about 12 years before evidencing wall failures. Other failures commonly mentioned include gear failure. Alternate drive methods (belts for example) or better gear design appear to be desirable design features, especially since at least some gears were found to exacerbate dragout levels. The newest barrel designs yielding the lowest dragout rates were too new to yield extensive service information. The slotted barrels and portable oblique basket plater were in use only for about 1 year without indication of any deterioration.

CONCLUSIONS

1. We have developed a procedure for benchmarking barrels used in various metal finishing operations. This procedure is relatively easy to conduct and can be conducted by any metal finisher at reasonable effort and cost. 2. We have demonstrated that there is a significant difference in dragout rate produced by different barrel designs, with newer designs reducing dragout rate almost 50%. Our results compare favorably with those reported by one barrel manufacturer4 who indicated that 26 to 49% reduction in dragout rate can be achieved by changing from a traditional barrel with drilled holes to one with a mesh pattern.

RECOMMENDATIONS

Based on this study we would recommend that any metal finisher utilizing traditional barrels evaluate the economics of changing over to one of the newer designs such as the portable oblique plating system or a newer design horizontal barrel incorporating either a mesh pattern or slots. The portable oblique barrel is a radical departure from existing barrel plating technology, and may offer advantages in plating efficiency not realizable in traditional horizontal barrel systems. Careful evaluation for suitability is warranted, due to the radical design difference. The favorable cost comparison and significant reduction in dragout rate make this system desirable. The slotted barrel appeared to us to be highly desirable in manual operations, where workers may not allow the barrel to drain fully. Since the slotted barrel appears to gush most of the liquid it will drain in the first few seconds, it would appear that this equipment would allow most of the dragout benefits, even when a worker impatiently moves a barrel to the next station prematurely. We are aware that our study was limited in scope and that there are numerous other barrel designs that may offer even better results. The benchmarking procedure described in this report can be used to yield comparative data on any of these barrels. Additional work that would be highly desirable is: 1. We would like to replace the conventional barrels at the metal finisher that allowed us to conduct this study with one of the newer designs and then obtain real- life dragout loss data, along with data on the ruggedness, plating efficiency differences (if any) and service life of the barrel. 2. We would like to have the opportunity to test barrels of other sizes and designs to yield a more complete guide for the metal finisher.

REFERENCES

1. Casey, G. J. and Asher, R. K., The Optimization of Barrel Zinc Plating Solutions, AESF Research Project 44, Plating & Surface Finishing. vo l. 66, August, 1979, page 51. 2. Craig Jr., S. E. and Harr, R. E., A Theory of Metal Distribution During Barrel Plating, AESF Research Project 34, Plating. vol. 60, June, 1973, page 617, December, 1973, page 1101. 3. LaVine, Mark, Choices, Metal Finishing. vol. 96, August 1998, page 36-40. 4. Stein, Berl, Teichmann, Robert J. and Thompson, Peter L., Mass Nickel Electroplating: A Comparison Study, Metal Finishing. vol. 90, July, 1992, page 42-45. 5. Tremmel, Peter H., Alternative Methods of Barrel Plating, Metal Finishing. vol. 97, March 1999, page 34. 6. Product Showcase: Barrel Plating, Metal Finishing. vol. 97, February, 1999, page 48-53.

Figure A-18 - Graphed Raw Dragout Data - Barrel Design 6 - Trial 3
318.00 286.00 0.665 3.140 4.140 5.890 7.430 9.200 10.600 11.800 13.200 14.700 15.800
ml dragged out per lbs/parts ---------------------------------5084.646 2054.403 3595.204 3163.780 3636.292 2876.164 2465.283 2876.164 3081.604 2259.843 3109.34 20.72892
30.000 Copper Level mg/L 25.000 20.000 15.000 10.000 5.000 0.10 Trial Number
12000.000 10000.000 ml dragged out 8000.000 6000.000 4000.000 2000.000 0.10 Trial Number

Page A-A-18

Figure A-19 - Graphed Raw Dragout Data - Barrel Design 7 - Trial 1
197.00 186.00 0.18 0.46 0.76 1.17 1.64 2.59 3.43 4.17 8.24 8.76 10.30

Barrel Design #7

ml dragged out per lbs/parts ---------------------------------928.55 994.87 1359.66 1558.63 3150.43 2785.64 2454.02 13497.11 ** 1724.45 ** 5107.02 ** 1890.26 * 12.60173 ***
30.00 Copper Level mg/L 25.00 20.00 15.00 10.00 5.00 0.4 Trial 7
12000.00 10000.00 mL Dragged Out 8000.00 6000.00 4000.00 2000.00 0.4 Trial 7
* Based on Samples 1-7 ** Not Included in Averages or on Graphs *** Does Not Include Samples 8-10 Page A-A-19
Figure A-20 - Graphed Raw Dragout Data - Barrel Design 7 - Trial 2
148.00 141.00 0.20 0.73 1.14 1.41 1.83 2.05 2.35 2.79 6.24 9.21 12.70
ml dragged out per lbs/parts ---------------------------------2339.52 1809.82 1191.83 1853.96 971.12 1324.26 1942.24 15228.95 ** 13110.14 ** 15405.52 ** 1633.25 * 10.88833 ***
* Based on Samples 1-7 ** Not Included in Averages or on Graphs *** Does Not Include Samples 8-10 Page A-A-20
Figure A-21 - Graphed Raw Dragout Data - Barrel Design 7 - Trial 3
117.00 108.00 0.02 0.18 0.29 0.30 0.35 0.73 1.57 2.19 8.00 9.00 10.00
ml dragged out per lbs/parts ---------------------------------893.40 591.88 61.42 256.85 2138.58 4690.36 3461.93 32441.65 ** 5583.76 ** 5583.76 ** 1727.78 * 11.5185 ***
12000.00 10000.00 mL Dragged Out 8000.00 6000.00 4000.00 2000.00 0.00 -2000.4 Trial 7
* Based on Samples 1-7 ** Not Included in Averages or on Graphs *** Does Not Include Samples 8-10 Page A-A-21
Figure A-22 - Graphed Raw Dragout Data - Barrel Design 8 - Trial 1
131.00 128.00 0.00 0.13 0.47 0.66 1.16 1.12 1.20 1.57 1.84 1.82 2.27

Barrel Design #8

ml dragged out per lbs/parts ---------------------------------798.36 2088.02 1166.83 3070.61 -245.65 491.30 2272.25 1658.13 -122.82 2763.55 1394.06 9.293715

Page A-A-22

Figure A-23 - Graphed Raw Dragout Data - Barrel Design 8 - Trial 2
130.00 121.00 0.27 0.65 0.79 1.04 1.26 1.43 1.65 1.79 2.01 2.31 2.43

Your Exam Content Outline
The following outline describes the content of one of the Vermont insurance examinations. The outlines are the basis of the examinations. The examination will contain questions on the subjects contained in the outline. The percentages indicate the relative weights assigned to each part of the examination. For example, 10 percent means that 6 questions will be drawn from the section on a 60-question exam, 10 will be drawn on a 100-question exam and 15 will be drawn on a 150-question exam. Vermont Adjuster's Examination for Workers Compensation Insurance Series 14-questions One-hour time limit 1.0 Insurance Regulation 9% 1.1 Licensing requirements Qualifications (4803(a)) Process (4800) 1.2 Maintenance and duration Renewal (4798) Expiration (4798) Records (4803(c)) 1.3 Disciplinary actions Denial of license (4800(3)(E)) Cease and desist order (3661) Suspension, revocation or nonrenewal (4804; 4806) Fines (4804(d)) Administrative penalties (RR 95-20 Rule 45 Sec 5000) 2.0 Workers Compensation Insurance 55% 2.1 Workers compensation laws and rules (RL 21 Sec 601711) Vermont Workers' Compensation Law and Department of Labor Rules (RL 21 Sec 602; RR 94-1 Rule 1.0000) Definitions (RR 94-1 Rule 2.0000) Exclusive remedy (RL 21 Sec 622) Employment covered (required, voluntary) (RL 21 Sec 616, 706) Independent contractor versus employee Statutory employer Covered injuries (RL 21 Sec 618620, 649) Benefits provided (RL 21 Sec 632635, 640 648) Out-of-state injuries (RL 21 Sec 619, 620, 623) Jurisdiction Subrogation (RL 21 Sec 624) Bars to recovery (RL 21 Sec 649) Willful intention Intoxication Failure to use safety appliance Statute of limitations Average weekly wage (RL 21 Sec 650; RR 94-1 Rule 15.0000) Choice of physician (RR 94-1 Rule 12.0000) Medical examination (RL 21 Sec 655; RR 94-1 Rule 13.0000) Notice of injury and claim (RL 21 Sec 656660; RR 94-1 Rule 3.0000) Compensation agreements and disputed claims (RL 21 Sec 662; RR 94-1 Rule 17.0000) Termination of compensation (RR 94-1 Rule 18.0000) Lump-sum payments (RR 94-1 Rule 19.0000) 2.2 Workers compensation and employer liability insurance policy General section Part One Workers compensation insurance Part Two Employers liability insurance Part Three Other states insurance Part Four Your duties if injury occurs 3.0 Workers Compensation Claim Principles 36% 3.1 Role of the adjuster Duties and responsibilities 3.2 Controlling medical costs Designated provider Medical fee schedule (RR 95-22 Rule 40.01.11) Hospital bill auditing Reimbursement requirements (RR 95-22 Rule 40.02) Fees for depositions, mileage and supplemental reports (RR 95-22 Rule 40.11) 3.3 Investigation and evaluation Compensability Employment relationship Compensable injury Casual relationship Timely notice Workers compensation fraud Documentation First report of injury Types of evidence Time limits Surveillance Adjuster's log notes Medical determination Medical authorization Casual relationship
Aggravation/recurrence Disability status Independent Medical Examinations (IME) 3.4 Claim reserves Components Indemnity Medical Expense Factors affecting reserves 3.5 Claims management Analysis Identifying treating physician Identifying treatment plan Identifying return-to-work capacity Contested claims adjustment procedures Form 27 (RR 94-1 Rule 18.0000) Notice and application for hearing; filing of papers (RR 94-1 Rule 4.0000) Representation (RR 94-1 Rule 5.0000) Informal resolution (RR 94-1 Rule 6.0000) Formal hearing (RR 94-1 Rule 7.0000) Appeals (RR 94-1 Rule 9.0000) Attorney's fees (RR 94-1 Rule 10.0000) Dispositions Resolving medical disputes (RR 94-1 Rule 14.0000) Resolving permanency disputes Settlement negotiation Form 14/Form 15 3.6 Vocational rehabilitation programs Referral (RR 94-1 Rule 30.0000) Individual written rehabilitation plan (RR 94-1 Rule 33.0000)