Document gaEBoaXVDBRMMgojZO3b5ybBG

ST0402866 PLAINTIFF'S EXHIBIT ENGINEERING SEMINAR NO. 30 September 29, 1976 Instil ation Linings Coatings Fiberglass Reinforced Plastic ST0402866 ST0U02361 TEXAS DIVISION ENGINEERING SEMINAR INSULATION The five basic reasons why we insulate are as follows: For Process Control; For Personnel Protection; For Freeze Protection; For Personnel Comfort; and For Energy Conservation. In each case different criteria are used to determine the most economical thickness. In COLD INSULATION (temperatures below ambient), the thickness is greater than the economic thickness. Cold insulation is designed to prevent condensation on the outer surface of the insulation. In Dow, Gulf Coast Area, the criteria used are ambient temperature of 90 F, relative humidity 852 and wind velocity 0 mph. The dew point in this situation is 85 F and the heat gain ranges from 4.6 to 7 BTU per hour per square foot of insulation. For PROCESS CONTROL thicknesses are governed by the desired energy loss; therefore, they also may be greater or less than the economic thickness. In processes where it is desirable to gain or lose heat, insulation may not be necessary and is not recommended. For hot equipment PERSONNEL PROTECTION, the outer surface tempera ture of the insulation should not exceed 150 F when the average ambient temperature is 70 F and the wind velocity 8 mph. Personnel should be protected from highly conductive metals, such as aluminum, when the metal temperature is above 145 F. Steel lines should have personnel protection at temperatures above 150 F. ST0402867 TEXAS DIVISION ENGINEERING SEMINAR - INSULATION Page 2 FREEZE PROTECTION as with PROCESS CONTROL insulation are special cases and thicknesses are determined for each set of conditions. PERSONNEL COMFORT is normally thought of as areas that would not he insulated except to allow employees to work in an area. F.NERCY CONSERVATION is usually associated with hot insulation, lor 11H11, energy conservation, massive amounts of insulation would lie inquired. Since it is not practical to talk of 100" conservation, the most beneficial amount is determined by economic analysis. Graph No. 1 shows how the thickness is arrived at. The minimum of Curve C is the economic thickness, which is usually arrived at by computer. The evaluations are based on the average annual temperature and the average wind velocity; however, it may also be necessary to determine the heat losses at the most severe conditions expected. Curve A is representative of energy cost and includes fuel costs, operation costs, steam plant maintenance, steam plant depreciation, taxes and return on investment. Curve B is the equal annual cost of insulation in dollars per square foot per year and includes applied insulation cost plus taxes multiplied by the capital recovery factor which includes " ROI and depreciation, and finally maintenance. ST0I.02868 ST0402868 ST0402869 COST MOTORS NUT: FUEL COST CAPITAL INVESTMENT COST OF MONET INTEREST DEPRECIATION MAINTENANCE NO. HRS. OF OPCR. INSULATION: CAPITAL INVESTMENT COST OF MONEY INTEREST DEPRECIATION MAINTENANCE INSULATION THICKNESS, INCHES <qR aph N.. 1 ST0402869 0 L 8 2 0 `)01S TEXAS DIVISION ENGINEERING SEMINAR - INSULATION Page 5 The current specifications in the 5A book are based on: Projected 1980 Steam Costs in 1975 Dollars = $2.91/M BTIJ 1975 In-Place Insulation Costs Average Ambient Temperature 68 F. Average Wind Velocity 8 mph 30 Annual Return on the Insulation 10-Year Depreciation Maintenance, 1% of Capital Insulation Cost Per Year Overhead, 1% of Capital Insulation Cost Per Year Taxes, 1.1% of Capital Insulation Cost Per Year By using a present worth factor all dollars are converted to the same time period. Material selection is the next determination to be made. The information needed to select the proper insulation material follows: RIGID POLYURETHANE FOAM is used primarily for cold insulation (temperatures below average ambient]. With proper care during appli cation to leave space for insulation expansion, as specified in specifications 56-508 and 56-558, polyurethane foam may be safely used up to a product temperature of 200 F. It is also used for freeze protection insulation. STYROFOAMS, which is a Dow product, is also an excellent cold insulation, but the solvents in vapor barriers attack the STYROFOAM. A barrier coat of a water miscible material, such as an emulsion or a latex can be put over the STYROFOAM. Then the vapor barrier can be applied. This is done, especially where the polyurethane is not ST0402870 I L 8 2 0 G0 1 S TEXAS DIVISION ENGINEERING SEMINAR - INSULATION Page 4 readily available. In the near future, a new STYROFOAM should be available that is resistant to vapor barriers solvents. The material is called STYROFOAM MA. FOAMGLAS (cellular glass) is used for cold insulation on vessels in hazardous areas. Foamglas alone is used up through Class N - (-25 F For Class 0 - (-26F) and colder 2" of Foamglas is put over the poly urethane to protect it from a possible fire. When this is done, 1" of the polyurethane insulation is deducted. For example, specification 56-576 calls for 5" thick polyurethane for Class R-6. In a hazardous area, where Foamglas is used as a thermal barrier to protect the poly urethane, only 4" of polyurethane would be used for Class R-6 with 2" of Foamglas. Usually, the thermal barrier is not used above 35 feet above grade. However, there are exceptions to this. Additionally, if normally cold equipment must be steam cleaned where the temperature will exceed 300 F, Foamglas can be used as the complete system, if above -20 F, or can be an inner layer with polyurethane as the outer layers, if below -26 F. In the second case, interface temperatures during the steam cycle must be calculated to determine the thickness of Foamglas to use. Foamglas is also used for hot insulation for specific conditions: For safety on piping carrying liquid flammables, such as ethylene oxide, - propylene oxide, hot oils, Dow Therms, etc. Foamglas, being cellular glass does not absorb these materials and therefore reduces the hazard if a line or valve containing flammable liquids should leak. ST0402871 ZL 820'lOiS TEXAS DIVISION ENGINEERING SEMINAR - INSULATION Page 5 For product temperatures from 200 F down to freezing, care must be exercized that no water gets between Foamglas and a steel surface. The Foamglas, being impermeable, will not let the water evaporate. This could result in corrosion under the insulation. HjS is the blowing agent used in Foamglas. This promoted corro sion when water was present, especially when there was breakage of the Foamglas which released H2S. A guide coat or in some cases 2-coats of paint over the primer should retard the corrosion. Finally, Foamglas has a higher "K" factor than other materials and requires additional thickness. Therefore, the cost is slightly higher on a square foot basis. Special conditions are needed to justify the use of Foamglas, so each case must be examined carefully. HEAVY DENSITY FIBERGLASS is used for hot insulation for the following conditions: For hot piping and equipment from 80 F up to 600 F, except it is not recommended for flammable liquids, nor for a thermal barrier. Foamglas is indicated for these two cases. Fiberglass is a good material to use. It has a better "K" factor than calcium silicate and a much better "K" factor than Foamglas, and the applied cost per inch of thickness is slightly less than calcium silicate and Foamglas. Light density fiberglass, being rather fragile, and therefore easily damaged, is not normally recommended, except inside buildings and other areas where it is not exposed to pedestrian traffic. ST0402872 ST0U02873 TEXAS DIVISION ENGINEERING SEMINAR - INSULATION Page 6 This material is recommended for pilot plants and temporary insulation. It is less expensive than heavy density fiberglass. MINERAL WOOL may be used in the same services as heavy density fiberglass, except it may he used up to 1,000 F. Some mineral wools have service temperatures up to 1,200 F, or higher. Forty-eight insulations MF wrap on mineral wool is easily applied and therefore may result in less cost than the preformed pipe insulation. CALCIUM SI LI CATE is a very good insulating material. Its "K" factor is better than Foamglas, but not quite as good as fiberglass. Since calcium silicate is hygroscopic, it should not be used where the process temperature will be below 200 F, nor should it be used on items that will be out of service for more than 1/4 of the time. Only asbestos - free calcium silicate is used because of the potential hazard of working with insulations containing asbestos. Because of the very low emissivity of aluminum, aluminun jackets are recommended for practically all insulation where the aluminum is corrosion resistant to the exposure. Aluminum jackets are comparable in cost to the standard finish on hot insulation; whereas, on cold insulation, the aluminum jackets are an added cost because they are placed over the standard vapor barrier. However, the aluminum jackets over hot and cold insulation actually save money because the aluminum retards heat flow due to its very low emissivity. ST0402873 ST0402874 TEXAS DIVISION ENGINEERING SEMINAR - INSULATION Page 7 For simplicity a flat surface is used in the following calcula tions. Similar results would be obtained on cylindrical surfaces using "equivalent" insulation thicknesses. Product Temperature, tp = 600 F Abmient Temperature, ta = 68 F Wind Velocity 8 mph Using 5" of calcium silicate insulation and a black finish, the heat loss is 45.08 BTU/S.F./Hr. ; and the outer surface temperature of the insulation finish is 83 F. The emissivity of black asphalt asbestos felt is 0.91 at 69 F. Whereas the emissivity of heavily oxidized aluminum is 0.20 at 200 F. The emissivity range of aluminum jackets is from 0.039 to 0.12; however, to be conservative 0.20 will be used in the examples. In the foregoing example, the radiation component of the heat transfer, using a black finish with an emissivity of 0.91, is 13.1 BTU/S.F./Hr. With an aluminum jacket, the heat transfer by radiation would be only: 2.9 BTU/S.F./Hr. This shows a difference in heat loss by radiation of 13.1-2.9, or 10.2 BTU/S.F./Hr., which is a considerable difference, considering that the total heat loss is only 45.08 BTU/S.F./Hr. However, this does not give the whole story. Under the conditions given the heat flow through the insulation would still be at the rate of 45.08 BTU/S.F./Hr., but since the combined radiation and convection heat transfer from the aluminum jacket at a service temperature of ST0402874 STO1(02875 EXAS DIVISION ENGINEERING SEMINAR - INSULATION Page 8 83 F and an ambient temperature of 68 F is less than 45.08 BTU/ S.F./Hr., the heat would be absorbed by the aluminum, thus raising its temperature to such a point that the heat transfer through the insulation equals the heat transfer from the aluminum. This, inci dentally .will then reduce the heat flow through the insulation since the AT will be smaller. Actually, the energy savings resulting from the use of aluminum jackets depends on the insulation thickness. If the insulation is thick enough, the surface finish would not have a significant effect on the heat transfer. For example, using only 2" of calcium silicate the aluminum jacket will show a six percent energy savings under the conditions given for case one. Whereas, with 6" calcium silicate the aluminum jacket will show only a two percent energy savings over a black finish. The energy savings will vary, of course, with the conditions. Graph No. 2 shows the change in heat loss due to rising surface temperatures (Curve A). The Curves B and C represent different rates of heat loss at certain surface temperatures with two different emissivities. B = .2 and C = .8. The energy savings is reflected in the change of heat loss Q. In this example, the energy savings is 3.3 BTU/F.S./Hr. with a total heat loss of 66 BTU/F.S./Hr. or 5% savings. Painting and insulating towers, piping and other equipment before erection can save expensive scaffolding, which can be a costly item. Large labor savings can also result because labor efficiency is greater on the ground, or a few feet above the ground, than it is a hundred feet or so in the air. On tow'ers a hundred and fifty feet tall. ST0402875 71 11/70 CHARGE NO.______ SUBJECT DOW CHEMICAL. U.S.A. TEXAS DIVISION SHEET AUTH. NO. FILE NO. _____ ___________ BY_____ ______________DAT E__ O PCHECKED BY. STO'-t 02876 ST0402876 ST040287? TEXAS DIVISION ENGINEERING SEMINAR - INSULATION Page 9 the labor efficiency will drop to around 1/3 of what it would be on the ground. Thus, savings in time and money can result. These savings can amount to several thousand dollars on a project. In fact, a study was made for pre-insulating towers on one project, which indicated the savings would be approximately $60,000. Pre-insulating applies only to towers that are fabricated prior to erection. Pre-painting and pre-insulating, in some cases, could reduce con struction time. This is very important. Where a month can be cut off of construction time, it would permit the investment in the plant to start making returns a month sooner than it otherwise could. Insula tion is quite often one of the last things to be done. Some of the towers on a recently constructed plant were painted and insulated before being erected. Pre-painting and insulating is planned for the Canadian vinyl job and is being considered for other projects. Towers on a Western Division job have already been done this way. Last but not least, painting and insulating towers before erection should be somewhat safer than doing the work on a scaffold after erection; safer for the men on the ground and safer for those in the air. ST0402877 TEXAS DIVISION ENGINEERING SEMINAR - INSULATION Page 10 In summation, the materials guidelines included in the back of this report are to be used in general cases. The guidelines are based on the facts presented in this paper. The included questionnaire is to help you determine if your specific job is a special case or not. If additional assistance is required, please feel free to contact me at 141S or come by my office at B-2402. vgm Attachments David W. Barnett Insulation Technology 8L920h01S ST0402878 ST0U02079 GUIDE LINE QUESTIONNAIRE 1. Is the equipment in a corrosive area? Caustic, Chlorine, etc. If yes, see Note A. 2. Does the equipment contain: E.O., P.O., Flammable organic liquid? If yes, see Note B. 3. Is fire protection needed? If yes, contact Insulation Technology. 4. Does the quipment vibrate? If yes, see Note C. 5. Is the operating temperature between 20 F and 250 F? If yes, see Note D. 6. Is the equipment made from aluminum or stainless steel? If yes, see Note E. 7. If the operating temperature is below 80 F, will the equipment be steam cleaned or the temperature get above 200 F ever? If yes, contact Insulation Technology. 8. Is insulation really necessary? Is insulation for energy conservation, process control, or personnel protection? NOTE A: Materials such as fiberglass and cellular glass foams are attacked by alkaline chemicals. In hot service, calcium silicate should be substituted in caustic areas, if the operating temperature is above 200 F. Aluminum jacketing is not recommended in either acid or alkali service, therefore, specify the felt jacketing. NOTE B: Some insulation materials may cause the auto-ignition temperature of a product to change. Check with the Glycol lab for your specific material and specify the insulation by trade name and manufacturer. They are not equal! In many cases, fire protection will also be required. Check! NOTE C: Block insulations are subject to vibration damage, especially Foamglas. Blanket type insulation may be layered under the block to prevent damage. A bore coating may also be used to reduce damage. In cases where vibration is severe, contact Insulation Technology for help. NOTE D: This temperature range can cause severe corrosion, through condensed ion, to your equipment. Additional coatings are required to prevent damage to the equip ment. Hygroscopic materials, such as calcium silicate, ST0402879 GUIDE LINE QUESTIONNAIRE Page 2 NOTE E: should not be used for operating temperatures below 200 F Also, special attention to the insulation finish (proper installation) is warranted. Special coatings are req uire d for aluminum and stainless steel. Calcium sil icat e materials should not be used on either. Spec ial care must be used in insulation materials selecti on. See chart for materials and coating selection. 0 8 8 ^0 l>01S D.W.BARNETT:vgm 9-16-76 ST0402880 ST0402881 28820*1015 TEXAS DIVISION ENGINEERING SEMINAR DESIGNING TO PREVENT LINING FAILURES Poorly designed equipment could possibly cause corrosion problems. Equipment with crevices, cracks, or pockets could fail due to corrosion caused by either oxygen or concentration cells. Products which are otherwise not corrosive to steel could become problems to hold, if the equipment has riveted joints or has internal parts which have only been skip welded. Definitely, poorly designed equipment will cause premature lining failures and application difficulties. The accompanying Engineering Specification Guide 57-301 covers some aspects that should be considered in designing and fabricating equipment for linings. Also, sufficient openings for adequate ventilation are required. Most lining systems contain some type of solvent which must be removed to prevent toxicity and/or explosion natards. The accompanying table shows the recommended ventilation for various sized tanks. To obtain the recommended ventilation, amDie size openings must be provided in the equipment. The minimum area in square feet of openings required is found b/ dividing the volume of the tank in cubic feet by 2,640. At least 2S"s of the opening area must be at the top. For example, tu obtain the necessary openings for a 23,00-gal Ion tank, divide 3,342 by 2,640 to get 1.3 square feet. Of this total, 0.3 ST0402882 TEXAS DIVISION ENGINEERING SEMINAR DESIGNING TO PREVENT LINING FAILURES Page 2 square feet are required in the top. A 24" manway has an area of 3.1 square feet, so only an 8" nozzle would be needed on top to meet the requirements for ventilation. vgm Attachments 9-16-76 G. T. Sikes C882060IS ST0402883 ST0402884 RECOMMENDED VENTILATION FOR VARIOUS SIZED TANKS This data is based on a specific coating. To obtain the giiloiu required of any coating lo make 1% by volume of solvent vapor in air: (a) Multiply the percent solvents by volume by the cubic ft of solvent vionr per gallon (Table 13-8). If there ere more than I solvent, multiply the percentage of each by the cubic ft of vapor per gallon and add them. Thu will give the cubic ft of solvent vapor per gallon of coating, fb) Divide the cubic ft of solvent vapor to make 1% by volume (Table 13-2. third column from the left) hv the cubic ft of solvent vapor per gallon of coating. This will give the gallons of coating required to make \% by volume of solvent vapor in atr. ST0402884 c;98Z0 l40iS ENGINEERING SPECIFICATION GUIDE Texas Division 57-301 7-15-74 Page 1G of 3g SURFACE PREPARATION AND LININGS GENERAL SPECIFICATION GUIDE 1. Purpose: This guide is to aid in the application of the specification of the same number. The guide is not normally issued to contractors. Please file in front of the specification. 2. Notes: 2.1 To obtain the maximum life from a lining, the equipment must be designed, fabricated, and surface prepared correctly. The following methods should be followed to eliminate application problem areas that could cause premature lining failure. 2.2 Design methods: Do Don't 1. Specify butt-welded vessels in prefer- ^ ence to lap- welded or riveted vessels. Grind Smooth Gap Gap Specify flanged and dished heads in preference to flat heads. T Grind Smooth Gap 3. Specify oversize and flanged outlets. ^-Round corners .Threads 4 v>sSharp corner ST0402885 ENGINEERING SPECIFICATION GUIDE Texas Division 57-301 7-15-74 Page 2G of 3g 2.2 Design methods (Contd.): 4. Specify that all con struction involving pockets or crevices should be avoided. 5. Specify that stiffener members be external tc the vessel. 6. Avoid interior use of rolled structural members such as angles, channels, etc., in a back-to-back position or lying flat against the vessel. 7. Avoid use of any arrangement whereby the chemical is pocketed and cannot drain. 8. Avoid use of long, curved nozzles where the interior cannot be reached or seen. Do Don't -?L Inside of Vessel Angle Stiffener - Skip r Weld Inside of Vessel If necessary, -"'specify full rro^seam weld f- Round --' Corners (----- ' . Skip ' Weld r3 Weep l/JTHole Round Edges 2 Channels Back-to-Back ^ Full Seam Weld Slf t n Wn 1 H Min. V ST0402886 9. Specify a minimum *j" clearance between nozzle wall and insert piping such as spargers and thermowells. Min. V ILs nru Min. V ST0402886 ENGINEERING SPECIFICATION GUIDE Texas Division 57-301 7-15-74 Page 3G of 3G 2.3 Fabrication Methods Do 1. Specify that all weld splatter be removed and all weld flux be removed. 2. Specify that all welds be free of under cutting, cracking, and pinholing. Clean /--------------- ^------/_ Ground Smooth Held Cross-section Plate 3. Specify that all welds be ground suitable for the anticipated lining L Plate Don't Weld Splatter t--f' 1 Held Flux Pinhole > Undercut _____ _ Plate t= Plate Sharp CnmT 2.4 The fabricator should understand the kind of welds required so that the welds can be made correctly initially and minimize grinding. 2.5 The Materials and Methods Development Department should be contacted if there are any questions on the methods listed above. 2.6 It is possible to apply a coating (not sheet) lining in a lap welded vessel, but failures are more likely and this should be avoided. L8820*101$ ST0402887 ST0U02888 TEXAS DIVISION ENGINEERING SEMINAR COATINGS COST OF PAINTING: According to the Texas Division Engineering Estimating Guide, the average cost of painting a new plant ranges from 0.9% to I.51 of the total cost of the plant. For a $300M plant, that can he as much as $4.5M. Any savings is always welcome, and our job is to save, without sacrifice, wherever we can. PRE-ERECTION OR POST-ERECTION PAINTING: To get the most protection for the money spent, consider where and when you want the painting done. Should you wait until the plant is erected or is it advantageous to have some or all of the painting done off site? IVhat are the advantages and disadvantages of pre-erection painting done off site? The advantages of having steel blasted and coated off site with a primer and at least one coat of paint extend beyond cost reduction. Between coat contamination is reduced. Plant startup is not interrupted by blowing sand and paint spray. Inspection is more easily performed. The job presents less safety hazards. There are disadvantages such as handling damage, weld or cut areas which require touch up, and difficulty in matching colors to a weathered paint. However, the advantages outweigh the disadvantages. ST0402888 68820*1 CHS TEXAS DIVISION ENGINEERING SEMINAR - COATINGS Page 2 OTHER FACTORS AFFECTING COST: Other factors which affect the cost are the degree of surface preparation required and the coating system necessary to protect against rusting. The most economical system for a particular job may call for the most expensive coating on the market or the cheapest. Usually, though, it is neither extreme, hut a compromise somewhere between. DEFERRED PAINTING: There is a way to effectively cut painting costs, if the environmental conditions permit. Is it necessary to do the complete paint job in the construc tion phase? Or, can the steel be abrasive blasted and primed before erection, and application of the guide and finish coats be deferred until a later date? The DERAKANE Plant in Joliet, Illinois was primed with inorganic zinc and painting put off for several years. At that future time, the protective coating for the zinc can be applied as a maintenance cost. By deferring finish painting, a savings of 40? is realized. Assuming the cost of painting to be 1? of the capital investment, the above 40? savings in painting translates into $4,000 capital saved per $1,000,000 invested. On a $300M plant, that's $1,251. Storage tanks at the Epoxy Plant, Texas Division, were primed with inorganic zinc and not top coated until around three years later. The primer was still in excellent condition. ST0402889 STOL02890 TEXAS DIVISION ENGINEERING SEMINAR - COATINGS Page 3 There i s a tank in the B58 Block which was primed with inorganic z inc about a year ago and is still not top coated, The zinc is compatible with the environment in this plant location. This is the mos t important criterion for deferred painting, What is the nature of the environment? GENERAL DESIGN AIDS: Before the plans for a new plant leave the drawing board, forethought and planning can eliminate corrosion traps through proper design. Some of the more important design tips are: 1. Avoid crevices. Moisture collects in them and results in severe localized corrosion. 2. Avoid sharp edges and corners. The surface tension of coatings causes the film to be thin in such places. Breakdown of the film results. 3. Grind welds smooth and remove weld splatter. Surface preparation is improved and coating can cover better. 4. Avoid skip or spot welding in highly corrosive areas or where moisture condenses. Fill crevices with mastic before painting. 5. Drain all surfaces so moisture will not stand. 6. Avoid lattice construction. Much of the surface is inaccessible to coating. 7. Avoid back-to-back angles for reasons listed in 6. 8. Avoid dissimilar metals or galvanic cells. The metal of higher EMF will sacrifice to protect the other. 9. Place tank relief vents and process vents where they ST0402890 ST040289I TEXAS DIVISION ENGINEERING SEMINAR - COATINGS Page 4 will not blow or spill on the paint and destroy it. CHOOSING THE CORRECT COATING SYSTEM: Consider the corrosion rate of the location when selecting a coating for a new plant. Corrosion maps of the Texas Division which define the corrosion rates throughout the division are available. After determining the corrosion rate of the area, the nature of the environment should also be determined. Is it acid or alkaline, neutral salts or merely marine environment? Will there be spillage of solvents or corrosive chemicals? Will the surface be subjected to fumes? What is the worst exposure? Corrosiveness Very Mild Mils Per Year Penetration 4.6 Lbs. Steel Losc/Sq.Ft. Per Year 0.19 Equipment & Coating MARINE Inorganic Zinc Painting ia pri- Galvanize marily for looks. Alkyd Thin Film Epoxy Surface Preparation NACE it 2 NACE #4 Neutral Mild 9.2 0.37 Acid Thin Film Epoxy Alkaline Thin Film Epoxy Salts Thin Film Epoxy NACE it2 Alkyd Galvanize* Alkyd Galvanize* Alkyd NACE //4 Galvanize* Medium 18.4 27.6 0.74 1.11 Chlorinated Rubber Thin Film Epoxy Thin Film Epoxy NACE it 2 36.8 1.48 Vinyl Vinyl Vinyl Tex Cote Tex Cote Thin Film Epoxy Severe 46.0 1.85 Chlorinated Vinyl Vinyl NACE it 2 55.2 2.22 Rubber Amine Cured Hi-Build Vinyl Ester Epoxy Epoxy Vinyl (Maximil) Tex Cote Tex Cote Hi-Build EpoxyCoal Tar Epoxy Hi-Build EpoxyCoal Tar Epoxy *Not to be used where subject to spills of corrosives. ST0402891 ZfiSZOhOlS TEXAS DIVISION ENGINEERING SEMINAR - COATINGS Page 5 A rule of thumb to remember is that protection is directly proportional to coating thickness. But, be sure it's the right generic type coating. Every now and then, we find the exception to a rule. Tex Cote is one such exception. Alkyds do not have the chemical resistance to withstand our severest environment nor should they be applied over inorganiz zinc. Tex Cote over inorganic zinc, provides good protection in highly corrosive areas; it is, as you have probably guessed, an alkyd. The Thermal Oxidizer struc ture in the B8 Block is primed with inorganic zinc and top coated with Tex Cote. In deciding the nature of the environment, remember that more than one system might be required. In chlorine cell buildings, both epoxy and vinyl paints are used. From 10' elevation down, the coating is epoxy because of alkaline cell effluent. Above 10', vinyl is used because the environment is acidic. WRITING THE JOB SPECIFICATIONS: The scope of the work should be very clearly defined. What is to be painted, and what is not to be painted. Be specific about what painting is done on site or m the contractor's yard. If the steel is only sandblasted and primed, remember that a primer left too long in a corrosive enviionment will not survive. Make provision in the specification so that an added expense will not be incurred to clean and rrprine the surface. ST0402892 ST0L02893 TEXAS DIVISION ENGINEERING SEMINAR - COATINGS Page t Texas Division and ECS Coatings Specifications cover approved paint suppliers and application procedures. These specifications are general in nature, and the engineer must anticipate problems peculiar to his own area. TEXAS DIVISION COATING SPECIFICATIONS: Texas Division Coatings Specifications contain lists of coatings which are used in the Texas Division, but do not define which coating is recommended for a particular service. A guide is being worked on which will aid in selection of coatings. If you have any recommendations, please submit them to me. COATING STAINLESS STEEL: One of the most frequently asked questions is, How should [ protect stainless steel? There are two situations which require that stainless steel be protected from chlorides which cause chloride stress corro sion cracking. Stainless steel equipment, awaiting erection and stored in the open, can collect enough chlorides from the industrial and marine environment atmosphere to cause cracking. It needs protection at this time. After the equipment has been erected and is ready for opera tion, it must have protection if the operating conditions are such as will promote cracking. Failures are most common at ST0402893 *ifi820*l01S TEXAS DIVISION ENGINEERING SEMINAR - COATINGS Page " 100 C, but have been known to occur at ambient conditions. If it is insulated, it must be coated to protect against leachable chlorides from the insulation. Several coatings have been used. The choice is governed by the operating conditions and service. Thurmalox 70, a silicone coating containing chloride inhi bitors, provides excellent protection for stainless steel. How ever, it does not withstand weather. It has a maximum service temperature of 800 F. It is used under insulation. Equipment which will not be operated above 300 F can be coated with Plasite 7122 or the epoxy paint specified in speci fication 57-227. Both are barrier coats which resist chloride penetration. Plasite 7122 is a phenolic-modified epoxy coating normally used as a tank lining. This material is not inventoried. The epoxy coatings in specification 57-227 call for an epoxy primer which contains zinc chromate. About 3% zinc and 200 to 400 ppm lead are present. If any welding is to be done, at any time, the coating must be removed so that no zinc or lead will be involved in the weld. This could lead to cracking. Epoxy coatings can be burned off, but caution is required. Harry Edwards, Environmental Health, has studied the effect of fumes from burning epoxies. A potential health hazard was found to exist if ventilation is inadequate. However, when proper ST0402894 TEXAS DIVISION ENGINEERING SEMINAR - COATINGS Page 8 precautions and safeguards are taken, the burning can be done safely. Sepcifically, burning should be done out of doors where the fumes will be dispersed in a place where ventilation is provided. RECENT DEVELOPMENTS: Actually, some of these "recent" developments have been around for a while. The economics now make them desirable. Others are new and offer features or properties heretofore unavailable. Some of the developments in the coatings field can be taken advantage of whether or not they are in our specifications. They can be written into individual job specs. FUSION-BONDED POWDER EPOXY PIPE COATINGS: First, the use of fus ion - bonded powder epoxy coatings is strongly recommended for pipe coating. This coating gives out standing performance above grade and below grade. It is avail able in a limited choice of colors but mostly in oxide red (or brown, as you prefer). The cost of coating larger size pipe is SO.35 per square foot, which is about one-half the price of the dope-and-wrap process. It can be color coated at a later date under a deferred painting plan. Powder epoxy coatings for pipe are covered in specification 57-277 and 57-277SP. ST0402895 I iii | i J | i ! ST0402895 TEXAS DIVISION ENGINEERING SEMINAR - COATINGS Page 9 i ST0402896 WATER-BASE EPOXY ACRYLIC PAINT: Second, an epoxy/acrylic water-base paint has been developed by Texas Division Research. This coating has excellent chemical resistance and is undergoing extensive lab and field tests. It is being used in the Mag 3 basement and in Plant B Mag Casting building. The latter application is over hand-cleaned steel. If these tests are successful, a specification covering this paint will be written. FUSION-BONDED POWDER EPOXY REBAR COATINGS: A third development is the fusion-bonded powder epoxy coating of concrete reinforcing bars. This was developed for bridges up north which are protected from freezing by salt. Penetration of salt through the concrete causes corrosion of the rebars and subsequent spalling of concrete. The added cost for the coating depends on the size of the rebar and the quantity ordered. The economics for your particular case would determine whether or not to use them. If you need more information, call John Tushek or me. SINGLE PACKAGE INORGANIC ZINC PRIMERS: Single package inorganic zinc primers have been introduced to the market. Ease of application, lack of mud cracking, and r pot life make this a desirable product. It is being tested in the lab now. We currently use a primer which requires mixing of the zinc powder into ethyl silicate liquid. All the mixed primer must be used or discarded the same day. The single package primer needs no mixing and any unused portion can be used later. ST0402896 TEXAS DIVISION ENGINEERING SEMINAR - COATINGS Page 10 COAL TAR MASTIC REPLACEMENT: The coal tar mastic coatings which have been used to protect piping in sleeper pipeways are being replaced with a new petroleum base product, Versa-Kote 1. Coal tars are very irritating to the skin and cause burns and this prompted the change. The applied cost of Versa-Kote 1 will be less than for coal tar. The required surface preparation is minimal and the recommended dry film thick ness is 12 mils, as compared to 1/8" for coal tar. A specifica tion will be written for this material. COATING FRP SURFACES 57-224: 16820101S Pigmented gel coats have exhibited poor adhesion and flake and peel away, exposing plastic surfaces to damaging ultra-violet rays. Lab tests have shown that epoxy paint adheres well to glazed FRP surfaces and a specification has been written. SUMMARY: Coatings costs of new plants can be controlled to get the most protection for the fewest dollars. Decide where the coating can be most advantageously applied, on site or off site, before or after erection. Decide if part of the coating can be deferred until several years hence and applied as an expense item. Utilize design aids to avoid corrosion traps and choose the coating to fit the requirements of the environment. Write a definitive job specification which incorporates Texas Division Coatings Speci fications. Finally, be aware of recent developments, and if they fill a need, use them in your plans. J . E.THOMSON:vgm:9 - 15- 76 i ST0402897 ST0402898 TEXAS DIVISION ENGINEERING SEMINAR FIBERGLASS REINFORCED PLASTICS I'm going to initially talk about the comparisons between metals and FRP. That's "fiberglass reinforced plastics" (commonly miscalled "fiberglass") for those of you who are unfamiliar with the terminology. After this comparison, I'm going to ask that you completely forget about metals when you design with plastics because plastics fabrication and metal fabrication are not and can not be accom plished in the same way using current manufacturing techniques. COMPARATIVE PHYSICAL PROPERTIES OF METALS AND REINFORCED PLASTICS" (Room Temperature) Table M Carbon rtrrt tOtO Density, Ih/in.'................................................ Coefficient of thermal expansion, in./fin.KTHIO-*)....................................... Modulus of elasticity, psi X 10*. in tension (Young's modulus)..................................... Tensile strength, psi X 10'........................... Yield strength, |isi X 10'. ......................... Thormnl conductivity, Utu/(hrKft*)<*F/fl)................................... Strength/weight rntio. Id'.......................... 0.283 6.5 hd.o m :t:i 28.O 2:10 Stainless sleet SIS Hatlrlloij C .Iftimi'nuni (ilnsatttal laminate Cam po.ti/rstructurr giaas-mat troten roving CrVn.lJrtinforeni *voiy, filamenttrorind* 0.280 0.324 0.098 0.0.10 0.06.1 0 1)6.1 0.2 6.3 13.2 17 13 o 12 28.0 85 35 26.0 80 50 10 0 12 4 0.7-1.Of 0-15 f 9-l5t 0.8-1.5 12-20 12-20 1 ft 4 1 too )<)( 0.4 G. .1 135 1.5 1 l .1 2.0 300 250 122 300 308 l.KMI ktk: The rrne't, figures used here for (he glass-reinforced plastic laminates are most conservative. For example, some filament-wound r|mxy (ensiles will run (o 300,000 Hi, giving them phenomenal strenglh/eight ratios of 4,500 X 10*. * Data on gloss-renifnrerd filnincnt-wnund epoxy Jinvc been drawn from a variety of sources. Filament w inding, in general, he it polyester or epoxy, will result in mueh higher physical strengths. t These doln are from the Keeninmended Product Standard for Custom Contact Molded Iteinforeeil Polyester Chemical Hrilant Process I'lquipmcnt, TS-I22C, Sept. IS, 1908. i ST0402898 TEXAS DIVISION ENGINEERING SEMINAR FIBERGLASS REINFORCED PLASTICS Page 2 You will note in the comparative table above that the physical properties of FRP vary greatly depending on the method of fabrication used, such as glass mat, mat roving, or filament wound. I would like to point out that the figure used for filament-wound epoxies is pretty optimistic, except under special conditions. Normally, we use about 45 x 103 psi for filament-wound structures. In filament-wound equipment, there is a difference in axial and hoop tensile strength. This difference depends on the winding angle used by the manufacturer. One item of particular interest to the designer is an under standing of how reinforced plastics break. The yield strength and the ultimate tensile strengths are the same. There is no bending or deforming of the reinforced plastics. Whereas, in metals the yield strength is a fraction of the metal's ultimate breaking strength. In service, failures of FRP, however, result in a "weeping" of the structures rather than catastrophic failures. This weeping effect is due to fiber separation when the resin fails. This mode of failure acts as a safeguard in warning the process people that immediate action is required to prevent further damage to the equipment. I don't mean to imply that catastrophic failure can not occur. It can and has, particularly in vacuum service. fifiBEOIOlS 1 I Another item of particular interest to the designer is the significant difference in elastic modulus of metals and reinforced i i ST0402899 ST0U0290U TEXAS DIVISION ENGINEERING SEMINAR FIBERGLASS REINFORCED PLASTICS Page 3 plastics. Due to its low modulus, reinforced plastic line can be installed with virtually no expansion joints or loops, if properly anchored. On the other hand, support members, beams, and columns must be looked at very closely in reinforced plastics design. A tall slender column can deflect alarmingly in a high wind. We very recently received a set of calculations on some stacks being fabricated for us and the vendor had neglected calculations on wind deflection. Both stress and strain calcula tions were within the specified limits, but even so, in a 124 mph wind, the deflection calculated to be 2 feet at the top of the stack. Our specifications allowed 2 inches. Another significant factor in the selection of materials is cost comparison. Attached is a cost comparison chart which with the help of Mr. D. D. Kennedy was developed about four months ago. This chart compares the cost of purchasing a glass-reinforced plastic storage tank with a similar vessel of other types of construction. In the late 1960's, FRP vessels still cost about one and one-half times as much as a 1020 carbon steel vessel. Some other advantages of FRP are: 1. Self-insulating, 2. Strength-to-weight ratio, 3. Maintenance against atmospheric corrosion, 4. Ease of handling during installation. ST0402900 TEXAS DIVISION ENGINEERING SEMINAR FIBERGLASS REINFORCED PLASTICS Page 4 5. Ease of repair, and 6. Nonconductivity. In all fairness to its metal counterparts, let me say, FRP does have its disadvantages: 1. Fire resistance, 2. Temperature range, 3. Poor solvent resistance, and 4. Low Young's modulus of elasticity. In my opening remarks, I said that you can't design with plastics (FRP) like you do with metals. I would like to explain why this is so. I'll do this by first describing to you what a corrosion-resistant laminate is. Lenlnating Seouence ! i Ii tt ST0U029Ul : Woven RoMng 1. For laminates 3/16" thick or less, use only Chopped strand mat for laminate interior. 2. Outside layer shall always be chopped strand mat, unless otherwise specified. ST0402901 TEXAS DIVISION ENGINEERING SEMINAR FIBERGLASS REINFORCED PLASTICS Page 13 A corrosion-resistant laminate is pictured above. The first layer (process side) is composed of a thin veil of glass, or synthetic material,such as Dacron, and is composed of 90$ resin and 10$ reinforcing. This is by far the most important part of ' ` i your laminate with regard to corrosion resistance. This veil layer and the next two layers of mat comprise what is referred to as the liner. The balance of the laminate, which' Is, alternate layers of veil and mat, is the structural or strength,supplying part of the laminate. When you speak of welding with metals, you mean in some way fusing two or more pieces of metal with heat and pressure, or with heat and a filler rod, so that the finished piece will be a more or less homogeneous piece of material; not so with FRP`. i, ' - In "welding" together items of reinforced plastics, we really mean overlaying two existing items with glass-resin layers (laminate) and actually bonding the two together in a manner which would probably be described as an adhesive bond.; This brings up problems not encountered in fusion welding. You no longer have a material of uniform thickness because the overlay must be of the same construction and thickness as the items joined. Consequently, problems of this nature may occur. ST0V02902 j | i } ST0402902 TEXAS DIVISION ENGINEERING SEMINAR FIBERGLASS REINFORCED PLASTICS Page 6 O' CD I !i i i E06Z010IS You will notice that the bolt circle fc is actually passing through the overlay where the flange was attached to the pipe. Seating a nut and washer on the back side of this flange will pose problems. This problem has been encountered on very heavy flanges in pressure service. Another example of how this type joining method may present problems may occur in connecting a bottom into a tank. A flat plate may not be welded to a cylinder such as is done on a steel tank. This would be such a weak joint that it would surely fail. In an FRP vessel, the bottom must be fabricated as an integral part of the bottom shell section. The attachment of a continuous flange-type ring around a vessel bottom as a method of anchoring the vessel introduces many problems to the fabrica tors. Consequently, we may receive unsatisfactory vessels, because we have imposed difficult laminating problems on the vendors. ST0402903 TEXAS DIVISION ENGINEERING SEMINAR FIBERGLASS REINFORCED PLASTICS Page 7 In designing any attachments onto an FRP vessel, one must be constantly aware that these attachments, lugs, clips, anchor devices, etc., must be attached using laminates which increase thicknesses and decrease working room. They cause bumps, uneven surfaces, increased thickness in some areas, and all of these conditions must be taken into account when considering bolting, washers, structure clearances, or ladder-platform situations. When we design joints in FRP, we do not consider weld efficiency as in metals. The governing factors are overlay thickness, laminate strength, and bond area, because these are the proper ties which give us our laminate integrity. To any of you who are unfamiliar with Texas Division Engineer ing Specifications 54-100 through 54-104, let me say that if you have to design with FRP, you can be 951 sure of getting a top quality vessel or fabrication of any kind, if you call out on the inquiry and purchase order that your equipment must be in accordance with these specifications. The 54-100 specification is an instrument designed to build quality into your equipment. The others are for specific types of equipment such as tanks, duct, pipe, etc. These specifications are a compilation of about 20 year's Dow experience, and all of the reinforced plastics information made available to us from outside sources over the years. They are excellent specifications and cover many areas of FRP fabrication which can not be included on drawings or *10620101$ r i ii f i ST0402904 TEXAS DIVISION ENGINEERING SEMINAR FIBERGLASS REINFORCED PLASTICS Page 8 purchase orders. They will keep you "warm and safe" at night. USE THEM PLEASE! In closing, I would like to remind you that all of the speci fications, calculations, and good intentions on earth won't buy good equipment unless the fabricator follows those directions, which you supply him. Inspection is an essential part of buying and installing good equipment in your plants. Inspection is the only real control you hold over a fabricator and then only if you have included a good set of specifications as a guide. Our inspectors first look for a good in-spec liner; this is the "life blood" of your equipment. You will find attached to this paper a Capital Project Review Checklist for FRP Equipment. This is an excellent guide to use when designing and buying any FRP equipment. vgm Attachments T. G. Hagemeier Engineering Projects Maintenance Technical Services ST0402905 ST0402905 TABLE A 6" SCHEDULE 40 PIPE DERAKANE - Custom Hand Lay-up DERAKANE - Filament-wound 304 Stainless Steel Monel Inconel Nickel Titanium Hastelloy B $9.42/ft. $11.70/ft. $37.48/ft. $128.50/ft. $146.91/ft. $178.00/ft. $259.63/ft. $289.00/ft. TABLE B TANK - 10' x 15' - 1/4" WALL FRP Filament-wound 3/16" FRP Hand Lay-up Carbon Steel Aluminum 3/8" Carbon Steel - Rubber-lined 304 Stainless Steel 316 Stainless Steel $3,780.00 $5,030.00 $8,400.00 $9,000.00 $14,100.00 $21,600.00 $24,600.00 vgm 7-19-76 STOL02906 ! I \ ST0402906 r- CAPITAL PROJECT REVIEW CHECKLIST FOR FRP EQUIPMENT 1. Have you contacted the Plastics 5 Nonmetallic Materials Section of Maintenance Technical Services? 2. Have you attached Texas or ECS Plastic Engineering Specifications? 5. For proper resin selection, it is necessary to consider all materials (even ppm) that may be in the process stream along with the operating and upset conditions (temperature and pressure). Have these been communi cated? 4. Should this piece of equipment have a post cure? 5. On applications involving caustic or hydrofluoric acid, has the proper synthetic surfacing veil been specified? 6. Has a BPO/DMA cured system been specified for hypochlor ites? 7. If a fire hazard exists has fire-retardant resin been specified? 8. Is pipe adequately supported? Plastic pipe requires more support than steel pipe. 9. Do pipe supports provide sufficient contact area? An area of 120-180 of circumference is desirable. 10. Are heavy valves and instruments independently supported? 11. Has hydraulic shock or water hammer, due to the closing of a valve, been considered? ST0402907 L0620101S CAPITAL PROJECT REVIEW CHEKCLIST FOR FRP EQUIPMENT Page 2 12. Have provisions been made for growth due to large thermal coefficient of expansion? 13. Discharge vents should be adequately sized to prevent over pressuring of tanks due to the AP between the escaping liquid (vent) and the tank intake. 14. Have vacuum relief devices been properly sized to eli minate accidental collapsing due to pumping or thermal conditions? 15. On vacuum vessels and ducts, are stiffeners sufficient for the required vacuum? Have temperature conditions been taken into account? 16. Are lifting lugs provided? 17. Are hold-down lugs provided? 18. Are the supports for tower internals adequate for the intended loads? _ 19. Can you eliminate all encapsulated metalhardware(clips, hangers, bolts, etc.)? This causes spalling and delamination. 20. Is a stainless steel that issusceptible tochloride _ stress cracking being used in a chloride atmosphere? 21. Are mating flanges the same? (ASA vs. Duct, duct to vessel) _ 22. Are an adequate number of Bell and Spigot joints designed into the system to allow for ease in assembly? _ 906Z0h01S i ST0402908 CAPITAL PROJECTS REVIEW CHECKLIST FOR FRP EQUIPMENT Page 3 23. Raised face pipe flanges should not mate with flat face FRP unless spacers are used to eliminate flange damage due to over torquing. 24. Have torque wrenches been specified for tightening all bolts where plastic flanges are used? Dow-lined pipe? 25. Are manways provided on all tanks and vessels when applicable? Handles on manway covers? 26. Sloped bottoms and drains that allow complete drainage should be considered when low ppm of RCl's and other highly corrosive materials are dissolved in the major liquid if they can settle or "layer" upon standing. 27. Do flat bottom tanks and vessels have full and proper support? 28. Have you contacted the Plastics 6 Nonmetallic Materials Section of Maintenance Technical SErvices? 3T0402909 JEC:vgm 3-20-75 ST0402909