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Chemical-resistant tanks and linings
CHEMICAL-RESISTANT TANKS AND LININGS
by C. E. Zarnitz Atlas Minerals & Chemicals Inc., Mertztown, Pa.
The dominant and most economical construction materials used in the metal-finishing industry are steel and concrete. Unfortunately, both of these materials are highly susceptible to corrosive attack from many of the chemicals used in the metal-finishing industry. Pickling and plating chemicals are highly corrosive and, without proper protection, the life span of steel and concrete is limited. Tanks and tank linings must be capable of: 1. resisting attack from organic and inorganic, oxidizmg and nonoxidizing chemicals at varying concentrations, as well as from various solvents; 2. resisting broad thermal variances including thermal shock; 3. resisting weather extremes because economics dictate that very large storage and waste treatment vessels be located outdoors; 4. resisting physical abuse that accompanies processing strip, heavy parts, shapes and castings; and S. maximizing performance, value, and ease of maintenance. TANKS AND LININGS
The type of tanks that have excelled in the metal-fmishing industries include lined carbon steel; lined, precast, or poured-in-place concrete; precast or poured-in-place polymer concrete; self-supporting plastics, i.e., thermosets and thermoplastics; and alloys. The success of steel or concrete-lined tanks is predicated on good engineering design of the structural shell. The ultimate success of the lining, besides good engineering design, is predicated on the finish and structural integrity of the substrate, as well as on the skills and proficiency of the applicator. If the structure cannot sustain the stress imposed by the process, lining failure is imminent. Similarly, plastic or alloy tanks will fail if good design engineering has been compromised.
Carbon Steel Tanks When fabricating carbon steel tanks for subsequent lining, the following are important: 1. Minimum number of pieces and sufficient reinforcement must be used to prevent bulging when subjected to optimum process stress. 2. Vertical reinforcing is preferred to horizontal. Ledges are eliminated, thus minimizing potential for drag-out to hang, concentrate, and corrode the vessel from the "outside-in." 3. Welds to receive lining are to be solid and continuous. 4. AIl comers are to be ground to a minimum radius of 1..1< in.; no sharp right angles. S. Exterior reinforcing members may be skip welded. 6. All body seams must be butt welded true and flat with variation on alignment not to exceed 25% of plate thickness and in no case more than 'AI in. 7. AIl outlets to be flanged. 8. Interior of vessel must be free of weld splatter, pits, deep gouges, and all welds ground smooth. The foIlowing typical.outlet and wel~ ~etails are s~ggested when fabricating carbon steel that will be lined with vanous types of hrungs (see FIgs. I and 2).
667
Tank Wa"
FiR. I. Flangrd nipplr outlets in tanks and covers . Welds "A" should be burned into plate so wrlds mt'('1 from opposite sides, Ihrrrhy excluding air pocket, Welds must he peened and smooth ,
JIm,,,,"
Stainless SteelTanks Stainless steel tanks can be compared to plastic tanks in the respect that they are solid steel. thus eliminating the need to protect a vulnerable exterior from fumes and splash. Stainless steels generally are classified as straight iron-ehromium alloys and iron-chromiumnickel alloys . In the metal-finishing industry. the iron-chromium-nickel alloys. i.e.. the 300 series appear to be the most popular. Types 302. 304. 321. and 347 are considered to be generally equivalent in chemical resistance. TIu: stainless steel alloys exhibit excellent resistance to such oxidizing acids as nitric and chromic. They have virtually no resistance to hydrochloric and hydrofluoric acids. The VUlnerabilityof stainless steels to halogenated acids is easy to understand when you recognize Ihat pidding solutions for stainless steel are acids such as hydrochloric and hydrofluoric lind various combinations of nitric and hydrofluoric. Figs. 3-5 provide typical oUllet and weld details for the fabrication of tanks .
Portland Cement Concrete Tanks Concrete tanks are acceptable SO long as good design engineering is practiced and includes: suflicient reinforcement to prevent buckling and cracking: minimum 3.000 psi ~~~---~r~l-_ Welding
Neck
t - - - - NIpple
Fig. 2. Flanged nipple outlets when welding neck is specified. Weld "8" to be laid in V in beads not to exceed ·'Ii••in. deep. After "8" is built up above plate outside, lire inner surface must be routed (Jut .mjJiciently 10 remove all scale and slag. Weld "C" is 10be buill up above the surface of plate, peened, and ground flush .
668
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(BOO) 423·2380 FAX (707) 778-8691 P.O. BOX 750338 • PETALUMA, CA 94975
Modern Electroplating by F. Louenbeim 801 pages $180.00
w. buitl I/,c beJI lun L
This is the third edition of this valuable textbook . Numerous authorities have contributed summaries on principles of plating and metal finishing, control, ma intenance, deposit properties , and troubleshooting. A worthwhile reference. Send Orders 10: METAL FINISllING 660 White Plains Rd., Tarrytown , NY 10591-5153 For faster service, call (914) 333-2578 or FAX your order to (914) 333-2570 All book order> must he prepaid Please Include $5 00 shipping and handhng for dehvery of each book \1141 liP S In the U ~ , SIO 00 for each book shipped express to Canada . and $2000 for t"'a ch book "ihlpp<.-d expre~ co all other countries
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QUALITY ElfGROPLATIN6 EQUIPMENT Engineered ~Ylteml and Componenn for Metal finilhing APPLE FABRICATION COMPANY QUA LI TY
EL.ECTRO~nHO
EOUIPItIENT
815 Mercury Ave.. Dallas. Texas 75137 Phone: 972-298-9898 Fax: 972 -298-8474
Fig. 3 . Pad outlets. Weld "D" is the same as "A," except penetration is not required. Drill two lis-in. diameter holes, 180·apart, through weld for vent. Weld "E" plate must be bevelled distance equal to thickness of tank wall. Weld is to be built up above the surface of plate. peened and ground smooth and flush with plate . compressive strength after 28 days; smooth. monolithic interior free of ridges, depressions, honeycomb. fonn marks . etc.; freedom from contaminants and additives. i.e.• form release agents. air entraining agents. etc.; and hydrostatically tight and waterproofed on the exterior if located below grade. Self-supporting plastic and stainless steel tanks must comply with similar structural mandates as those enumerated for carbon steel and Portland cement concrete.
Polymer Concretes Polymer concretes are a generation of materials that have rapidly matured because of their outstanding chemical resistance and physical properties. They are not to be confused
Inside Tank
.p Fig. 4. Corner of rectangular tank. Weld "F" should be burned into plate so welds meet from opposite sides. thereby excluding air pockets . Welds must be peened and ground flush .
.:~£T.n.
K'SS~_=sJ °Go
Fig. 5. Butt joint. Weld "G" to be laid in V in beads not exceeding 31J6-in. deep After "G" is built up above plate on outside, the inner surface must be gouged out sufficiently to remove all scale and slag. Weld "H" is to be built up above the surface ofplate. peened and ground flush.
670
Table I. Typical Physical Properties of Polymer Concretes Tes/ Me/hod
Property
ASTM ASTM ASTM ASTM ASTM ASTM
Tensile strength. psi (MPa) Compressive strength.psi (MPa) Flexural strength , psi (MPa ) Linear shrinkage. % Density. Ib/fl3 Water absorption, % Maximum use temperature. ' FCC) Continuous Intermiuent Thickness. in. (rnrn) 1l1e chemical resistance of polymer concretes
C 307 C 039 C 580 C 531 D 792 C 413
Typical Value 1.000-2.000 (7-14) 10.000-12.000 (70-&2) 2.000-4.000 (14-28) < 0. 1 130--145 (2.1- 2.3) < 0.1 150 (66 ) 200 (93) 0.5 (13)
IS
similar to their synthenc resin lining systemcounterparts as mdicated
In
Table VII.
with portland cement concrete or polymer-modified Portland cement concrete, The only similarity to portland cement concrete or polymer-modified Portland cement concrete is the use of properly graded and sized aggregate in order 10 optimize workability and physical properties of the composition. P?lymer concretes utilize inert siliceous aggregates with binding systems based on such resms as furan, epoxy, polyester, vinyl ester, and acrylic . (See Table I for typical physical properties of polymer concretes.) The advantages to be derived from polymer-modified Portland cement concrete when compared with portland cement concrete are:
1. 2. 3. 4. 5.
Permits placement of concrete in thinner cross-sections. Excellent bonding to existing concrete substrates. Increased impact resistance. Reduced porosity. Faster set and cure. 6. Improved resistance to salt. It does not improve resistance to chemicals.
polymer modifiers are generally based on various resins and latexes. such as natural rubber. styrene-butadiene, acrylic . polyvinyl acetate, epoxy. and urethane.
LININGS There are a host of lining matenals available for protecting concrete and steel. The three ic types are glass-fiber-reinforced sheet and molten asphaltics; sheet rubber, plastics, and ~Sstomers; and reinforced and nonreinforced ambient-eured synthetic resin systems. e a ConspicuouS by its absence from this list is protective coatings. This is not to say they 'I be used; however, 60 mils is usually considered 10 be a minimum acceptable thickness ~: a maleriallo be consid:~ed a tan~ lining . If a co~ting can be .economically applied (initial t and longevity) 10 a nummum thickness of 60 mils, free of pinholes and holidays. and can co~ t the process chemicals and temperatures as well as physical abuse, consideration should restS . e fume and splash protection and be iven to their use. GeneraIly spe akimg, coatmgs are use d lor gl ecessarily for total immersion process applications. not nAsphaltic linings . . i or app I"icatron to concrete and steel. The are equ all y appropnate 'ed molten materials, as well as sheet stock can be used on concrete tanks For steel ppll hot-a ' . . the most desirable. ' ' k glass_fiber-remforced sheet IS Both types of asphaltic linings, sheet t~ s, olten, are seldom, if ever, used without being further protected with a chemical-resistant an. k~jning. Without further protection from a brick sheathing, these linings can cold flow and bric "b ' . M asonry sheathings be easily damaged from Impact, a rasion, an d th erm aI excursions. b
671
Table II. Physical Properties of Asphaltic Linings Value
Properly Softening point. ' F r e) Ash. max .. % Pene trat ion 77'F (25T ). 100 g-s-Ssec .
II S"F (46·C). 50 g-5sec. Chemical resistan ce
Type A
TypeD
200-225 (93-107)
250-275 (121-135)
0.5
O.S 18
38 75
27
Very good
Very good
provide a rugged. chem ical-resistant insulating barrier for protection of asphaltic as well as other Iypes of linings. The physical properties and the chemical resistance of asphaltic linings are shown in Tables II and III. respectivel y. Adhesive-bonded sheet linings, such as various plasticized plastics. rubbers and elastomers are most commonly used for steel tanks. Successful applications have been made on concrete: however, it is not the most desirable substrate on which to bond and cure many of these systems . The physical properties and the chemical resistance of sheet linings are shown in Tables IV and V, respectively. Mechanically bonded rigid plastic linings/or precast and poured-in -place concrete tanls are a relatively new conce pt. Instead of bonding with adhesives. this system utilizes anchor studs sonically welded to the back of the sheet for locking or mec hanically bonding the sheet to the concrete. Ambient temperature-cured. spray- and trowel-applied synthetic resin lining systems are based on the fo llowing resins: furan, epoxy. polyester, vinyl ester, and urethane. The se systems are entirely appropriate for application to steel and concrete. They have also been successfully applied to wood, certa in plastics, and various metallic substrates. These
Table III. Chemical Resistance of Asphaltic Linings M edium
Alum inum salts Cadm ium sa lts Chromic acid. 10 10% Copper salts Gold cyan ide Hydrochloric acid Hydrofluori c acid Iron salts Magnesium sa lts Nickel sa il.'> Nitnc acid . 10 20% Perchloric acid Phosphori c acrd Sodium chloride Sodium cyanide Sodium hydroxide, to 30% Sodium salts Sulfuric acid, 1050% Trichloroethylene Trisodium phosphate Zinc salts
Type A R
R
R R R R R
R R R R
R
C
C
R R
R R R
R C
C
NR R R R
NR R R R
R
R
R R NR
R R NR
C
C
R
R
C. conditional: R. recommended; NR. not recommended.
672
Type B
round tankl
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••••••••••••••••••••••••••••••••••••••••••••••••••••• The Chemical Analysis of Electroplating Solutions by T.ll. Iroine
182 pages
$75.00
Chapters in this work are divided int~ _woup.< in al::ordancc with the penodtc table of ell" rnenlS. 11lough the procedures are traditional, theoretical aspects are included with other information. Anyone who studies this book carefully will derive a helpful undcrstandinR of what he or she is doing so that unexpected results can he searched out for cau10CS and mm'('1l'd Send Orders to- METALFINISIIING, 660 White Plains Rd., Tarrytown, NY 1OS91-'i1'i3 For faster service, call (914) 33.}-2';7fl or FAX your order to (914) 333-2'i70 All blK'k n,der,. must he prepaid. Please inc!ude $~ .OO shippinll and handlinll for ddivcry of each h,.,k vill UP~ In the U.S , $1000 for each book shipped "xp,,,,,"' In Canada. and $lO.OO fo' ,'a,h lx••k shipp,-d expres.'" to all other countnes.
Tuble IV. I'hy slcal Propt'rlles or Sh ed Lin ings rt'mpt'raturt' Rrsistunr«
Max.. "F (t:J
Chemica! Ru;stullft
1 ~ (66)
Verygood Verygood Verygood Verygood Verygood Very good
Nutural rubber Sufi Scmihurd IInnl Neoprene 8alyl ",hller Chloruhulyl rubber Polyvinyl chloride 1'lasliciU'd 1'1w.lici,.t"d rigid (2 ply) Chlon.."lfunalcd polyethylene T·' aurllcdfl'un.
1110 (!l2) 180 (82) 180 (112) IMS (8S ) 18S (MS )
Elcellent Elcellent Very good Em: llenl
1~(66)
I SO (66) 275 (135) 450 (232)
lining systems utilize such filler reinforcements as fluke glass and mica. Fabric reinforcements such as fihcrglass arc the most common; however. synthetic fabrics are used where Iluorides are present, These linings are extremely versatile and can be applied by maintenance personnel with skills in the pninling and masonry trades, Most manufacturers of these lining systems provide training programs for plant maintenance personnel. The physical properties and the chemical reslsnmce of umbient-cured synthetic resin lining systems are shown in Tables VI and VII. respect ively, Table V. Cheml cal Resistance or Shed Lin ings M..J,um
Alununum IllIIiI Cadnllurn .nhl Chmrmcacid. 10 IO'J, Copper ...h. Gllid cyanide Ilydrochiurie acid lIydmnlluric acid Imn . aU. MlIgneliulll oalll Nickel ...h. NllflC acid. 10 211':¥o Pen:hloflc acid 1~l mllh"flc acid Sud/urn chloride Sodium cyanide Sodnnn hydrolide, 10 30% Sotliarn lIlIlls Sulfuric acid. 10 20% Tnchloroeurylene Trisodium ph""phllle
Zinc oulla
'"
R R NR R R R R R R R NR NR
R R R R R R NR R R
R. rc'C'nmmtndcd. C. CondlllOJUlI: NR. not m:ommcndcd.
2
J
4
j
6
R R NR R R NR NR R R
R R NR R R R R R R R R NR R R R R R R NR R R
R R R R R R R
R R R R R R NR R R
R R R R R R R
R
NR NR
R R R R R R NR R R
R
R R R C
R R R R R R NR R R
R
C
NR R R R
R R R NR R R
'I • nUland ruhhcr-llil In,dcI; 2 • Neap~n. : J • Bulyland chlorobulyl; 4 • polyvinyl chloride; S • chlorooulfonal
674
R
R R R R R R R R
R R R
R R
Table VI. Physical Properties of Ambient-Cured Synthetic Lining Resin Systems Temperature Resistance" Max .•
Type
FCC)
Chemical Resistance
125 (52) 160(71) 180 (82) 160 (71)
Furan Epoxy Polyester Vmyl ester
Excellent Very good Very good Very good Good
150 (65)
Urethane 0Suggested lmut Without a masonry shealhmg.
The tables shown above all provide the design and corrosion engineer with basic information on the various lining systems discussed. They identify specific corrosives encountered in various metal-finishing operations. Enumerated are each of the various types of linings and a general recommendation for its use in the particular medium. It is recommended that the acceptability of specific linings, in specific media, be verified with the manufacturer.
Chemical-Resistant Brick and Tile Linings Historically, chemical-resistant brick and tile linings go back approximately 100 years, paralleling the development of sulfuric acid, various dyestuffs, and explosives. The use of masonry construction has grown in the basic steel, metal-working, and metal-finishing industries. Chemical-resistant masonry sheathings are not to be construed as hydrostatically tight tank linings. They are, in fact, porous, and consequently must be Table VII. Chemical Resistance of Ambient-Cured Synthetic Resin Lining Systems MedIum
Aluminum salts Cadmium salts Chromic acids, to 10% Copper salts Gold cyanide Hydrochlonc acid Hydrofluonc acid Iron salts Magnesium salts Nickel salts NItric acid. to 20% Perchloric acid Phosphoric acid Sodium chloride Sodium cyanide Sodium hydroxide. to 30% Sodium salts Sulfuric acid. to 50% Trichloroethylene Trisodium phosphate Zinc salts
r
2
3
4
5
R R NR R
R R NR R
R R R R
R
R
R R R R R
R Rb R
R R R
R R
R
R R R
R R C R R R C R
R
R
R
R
R
R NR NR R R R R R R R
R
R
R
NR NR R R R R R C NR
R
R
NR R R R R R
NR R R R R R R
R
R
R R C R R R Bis A Type R R C Bis A Type
R
R
R
R
R
NR R
NR
R
R
R
R. recommended: C. condmonal; NR. nol mcommended. "l = furan, 2 = epoxy: 3 = polyester. 4 vmyl ester. 5 = urethane 'Carbon filled matenals and/or final apphcallon willi syntheliC fabncs.
=
675
Table VIII. Chemical Resistance of Structural Plastics M~dillm
Aluminum salts
Cadmium salts Chromic acid. 10 10% Copper ,all' Gold cyanide Hydrochloric acid Hydrofluonc acid Iron salts Magnesium salts Nickel salts Nitric acid. 10 20% Perch loric acid Phosphoric acid
Polyvinyl Chloride
Polyethylene
Polypropy/~nt
R R R R R
R R R R R
R R R R R R
R
R
R R
R
R
R
R R
R R
R
R
R
R
R
R R
Sodium chloride
R
Sodium cyanide Sodium hydroxide. 10 30% Sodium salts Sulfuric acid. to 50% Trichloroethylene Trisodium phosphate Zinc salls
R
R C
C
R R R R
R R R R R
R R R
R R
NR
NR
R NR
R
R R
R R
R
C, condihonlll; R. recommended, NR. not recommended.
con~idered as chemical. physical, and thermal barriers for protecting membranes installed
~hJnd these sheathings. Brick sheathings contribute to the longevity of tank linings by
nlfe~ing additional chemical, thermal, and physical protection. They are excellent insulating
barriers and, consequently, can be considered as energy savers.
PLASTIC TANKS AND LININGS There are a multitude of plastics available for solving corrosion problems in the metal-finishing industry. The more popular and cost effective are polyvinyl chloride (PVC). Type I; polypropylene (PP); linear polyethylene (PE); and fiberglass-reinforced plastics (FRP). All of these plastics have been successfully used as self-supporting tanks and "drop-in" tank liners for process and storage applications. The thermoplastics (PVC, PP. and PE) are being used for mechanical bonding to concrete for similar applications. Polyvinyl chloride is one of the oldest proven plastics for fabricating highly chemicalresistant structures. (See Table VIII for the chemical resistance of structural plastics.) Type I PVC is one of the best plastics available for resistance to a multitude of strong oxidizing environments up to its thermal limitation of approximately l50'F (66'C). Type I PVC has outstanding structural integrity attributable to its high tensile, compressive. and flexural properties. It is one of the easiest plastics from which to construct tanks. tank liners, dipping baskets, and other storage and process equipment. PVC is easily thermoformed. cut. drilled, tapped, machined. and welded, consequently, making it an excellent, versatile, and cost-effective material from which to fabricate corrosion-resistant equipment. Polypropylene has arrived. Its popularity is attributable to its excellent chemical resistance and surpasses PVC because of its superior physical and thermal resistance. It is available as name and nonflame retardant homopolymer and copolymer sheet stock. Polypropylene utilizes fabricating techniques similar to those used for PVC. Small tanks for
676
pickling and plating. large tanks for continuous strip pickling lines. and pickling line covers have been fabricated of polypropylene. These and similar fabrications are enjoying an enviable record of success in challenging chemical and physical applications. Linear polyethylene fabrications have performed well in the small-parts metal-finishing industry because of their low absorption. high chemical resistance. and outstanding resistance to impact. They do not possess the rigidity and flexural capabilities of PVC or PP and. consequently, the fabrications are significantly smaller. A new generation of PE is making significant inroads into the finishing industry. Crossli~kable, high-density PE for rotational molding is being used for tanks of 5-10.000-gal capacity, These new resins exhibit excellent physical properties and good resistance to weathering. Applications for the most part have been indoor and outdoor storage tanks and portable receiver tanks. Fiberglass-reinforced plastics have been successfully used for a multitude of applications for many years. The earliest fabrications utilized furan and phenolic resin binder systems. The more popular resin binder systems in use today are polyester, epoxy, and vinyl ester. The success of FRP structures is substantially predicated on the proper choice of resin and hardener system most inert to the environment to whiqh the fabrication will be subjected. It is not enough to request an FRP tank. any more than it is to request a flake-glass-reinforced polyester tank. It i.s impo~t to either provide ~he fabricator with all chemical, thermal. and physical information pertinent to the. process 10 or~er that the proper resin and hardener system might be selected. or to have in-house technical competency capable of making the proper selection of the resin-hardener system from which the manufacturer can fabricate the desired equipment. There are numerous polyester resins available; however, for aggressive corrosion environments. such as high concentrations of alkalies and a broad range of acids, the bisphenol-A fumarate resin is the best recommendation. Vinyl esters are epoxy-resin-based, thermosetting resins that provide chemical resistance similar to that of bisphenol A polyesters. They are considered to be slightly better in high concentrations of.alkaline hy~ochl.orites th~ the bisphenol A polyester. Vinyl esters exhibit ou~tanding physical properties, r.e., tensile, flexural, and elongation that are normally associated with epoxies. The chemical resistance and physical properties of epoxy resins are functions of the resins. but equally important, they are .very much functions of the curing systems employed. Aliphatic and aromatic amine cunng systems impart better chemical resistance to epoxy resins than do polyamide curing agents. Polyamides, however, impart better impact resistance to epoxies than do aliphatic or aromatic curing systems. The intention of these three examples of the resin systems utilized for constructing fiberglass-reinforced tanks and t~k linings is to point out the necessity of knowing the chemistry of the system. or relying on reputable manufacturers to provide the technology required to make the best selection to ~ulfill end use requirements. Where the chemistry of these various systems contributes substantially to the physical properties of the structure. the most profound influence on physical properties is derived from the proper design and use of various reinforcing mediums, i.e.• glass fibers, glass cloth. roving. mat. veil. etc. Cons~lt reputable manufactu.rers for proper design consistent with the douse mandates for chemical, thermal. and physical properties. en The chemical resistance of FRP is comparable to the chemical resistance data shown in Table VII. Table ~IIl summarizes the che~ic~1 .resistance of P~C. PE, an~ PP. The mechanically bonded thermoplastic lining system previously described circumvents many of the limita~ion.s .inherent in some pl~stics, as well as coating. and many other elustomerie and resin Ilning systems. The s~mcally wel~ed anchor studs are of the same lustic as the sheet and ~ placed ~t .a~proxlmalely 2-3 m, on centers. Sheet thickness and p nor stud density provide the rigidity necessary for a successful thermoplastic lining anc li cation. The studs. being of the same plastic as the sheet, ensure thermal and physical app I .., Th e I'mmg . sys tem . f or new and eXisting . . concrete, . as properlY slmllanty. em iIS equaIIy appropnate
677
well as for salvaging used steel tanks. Upon removal of the concrete forms and the welding of all joints, utilizing thermoplastic welding techniques. spark testing is used for quality assurance of the lining. The system is available in a single- or double-wall system to ensure compliance withthe most rigid of environmental mandates. Leak detection systems are available and are integral with the lining system.
FABRICO TANK LINERS FOR TOTAL LEAK PROTECTION.., Prlll1llry Contalnm.nt 1 ForPlating T.nka Fabrlco Lintf1118 QlSlOm lIesigned 10 1M lht dimensions ofyour tank. They provide &xcell.nt resistance 10 COIIOSIvt attack bypla~ng solutions and oxidizing ,gentl.ln,tlllatlOn II quick and easy andcan usually be don.by your maintenlll1C8 peopl•. Fabrico Lintf1 can meet EPA guldlints,save you money, require less maintenance and stop hazardous leaks.
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678
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C©~(P>©~~i1'U(o)H
CallToll Free 800-255-6245.
913-362·9400, Fax 913·262-1234. E·Mall [email protected] Internet http://www.sky.nel/~amllnlng 5940Reeds Rd. Mission, KS 66202
by C. E. Zarnitz Atlas Minerals & Chemicals Inc., Mertztown, Pa.
The dominant and most economical construction materials used in the metal-finishing industry are steel and concrete. Unfortunately, both of these materials are highly susceptible to corrosive attack from many of the chemicals used in the metal-finishing industry. Pickling and plating chemicals are highly corrosive and, without proper protection, the life span of steel and concrete is limited. Tanks and tank linings must be capable of: 1. resisting attack from organic and inorganic, oxidizmg and nonoxidizing chemicals at varying concentrations, as well as from various solvents; 2. resisting broad thermal variances including thermal shock; 3. resisting weather extremes because economics dictate that very large storage and waste treatment vessels be located outdoors; 4. resisting physical abuse that accompanies processing strip, heavy parts, shapes and castings; and S. maximizing performance, value, and ease of maintenance. TANKS AND LININGS
The type of tanks that have excelled in the metal-fmishing industries include lined carbon steel; lined, precast, or poured-in-place concrete; precast or poured-in-place polymer concrete; self-supporting plastics, i.e., thermosets and thermoplastics; and alloys. The success of steel or concrete-lined tanks is predicated on good engineering design of the structural shell. The ultimate success of the lining, besides good engineering design, is predicated on the finish and structural integrity of the substrate, as well as on the skills and proficiency of the applicator. If the structure cannot sustain the stress imposed by the process, lining failure is imminent. Similarly, plastic or alloy tanks will fail if good design engineering has been compromised.
Carbon Steel Tanks When fabricating carbon steel tanks for subsequent lining, the following are important: 1. Minimum number of pieces and sufficient reinforcement must be used to prevent bulging when subjected to optimum process stress. 2. Vertical reinforcing is preferred to horizontal. Ledges are eliminated, thus minimizing potential for drag-out to hang, concentrate, and corrode the vessel from the "outside-in." 3. Welds to receive lining are to be solid and continuous. 4. AIl comers are to be ground to a minimum radius of 1..1< in.; no sharp right angles. S. Exterior reinforcing members may be skip welded. 6. All body seams must be butt welded true and flat with variation on alignment not to exceed 25% of plate thickness and in no case more than 'AI in. 7. AIl outlets to be flanged. 8. Interior of vessel must be free of weld splatter, pits, deep gouges, and all welds ground smooth. The foIlowing typical.outlet and wel~ ~etails are s~ggested when fabricating carbon steel that will be lined with vanous types of hrungs (see FIgs. I and 2).
667
Tank Wa"
FiR. I. Flangrd nipplr outlets in tanks and covers . Welds "A" should be burned into plate so wrlds mt'('1 from opposite sides, Ihrrrhy excluding air pocket, Welds must he peened and smooth ,
JIm,,,,"
Stainless SteelTanks Stainless steel tanks can be compared to plastic tanks in the respect that they are solid steel. thus eliminating the need to protect a vulnerable exterior from fumes and splash. Stainless steels generally are classified as straight iron-ehromium alloys and iron-chromiumnickel alloys . In the metal-finishing industry. the iron-chromium-nickel alloys. i.e.. the 300 series appear to be the most popular. Types 302. 304. 321. and 347 are considered to be generally equivalent in chemical resistance. TIu: stainless steel alloys exhibit excellent resistance to such oxidizing acids as nitric and chromic. They have virtually no resistance to hydrochloric and hydrofluoric acids. The VUlnerabilityof stainless steels to halogenated acids is easy to understand when you recognize Ihat pidding solutions for stainless steel are acids such as hydrochloric and hydrofluoric lind various combinations of nitric and hydrofluoric. Figs. 3-5 provide typical oUllet and weld details for the fabrication of tanks .
Portland Cement Concrete Tanks Concrete tanks are acceptable SO long as good design engineering is practiced and includes: suflicient reinforcement to prevent buckling and cracking: minimum 3.000 psi ~~~---~r~l-_ Welding
Neck
t - - - - NIpple
Fig. 2. Flanged nipple outlets when welding neck is specified. Weld "8" to be laid in V in beads not to exceed ·'Ii••in. deep. After "8" is built up above plate outside, lire inner surface must be routed (Jut .mjJiciently 10 remove all scale and slag. Weld "C" is 10be buill up above the surface of plate, peened, and ground flush .
668
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roo YfAR COMMITMENT TO QUALITY, SERVICE AND CUSTOMER SAnSFACTJON ~ [af5Ofl bners are custom manufactured fa fit any size, shape orconfiguration requirements. Our liners are constructed using an electronically lap-weided seam process which assures superior strength. Drop-in instalation is easy ancl fast. • IfJghest Wty • 3 Grades of Materiol • ChemicoJ Resistant • MoinIenonce Free • Milimal Downtime • Toicol Consultation ·lhKknesses Avoiloble-.012·3/16" • High Temperature Formulotions • Floor Covering for Secoodory Con1ainment, Sumps, Pits, Trenches • Excellent for Ele
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(BOO) 423·2380 FAX (707) 778-8691 P.O. BOX 750338 • PETALUMA, CA 94975
Modern Electroplating by F. Louenbeim 801 pages $180.00
w. buitl I/,c beJI lun L
This is the third edition of this valuable textbook . Numerous authorities have contributed summaries on principles of plating and metal finishing, control, ma intenance, deposit properties , and troubleshooting. A worthwhile reference. Send Orders 10: METAL FINISllING 660 White Plains Rd., Tarrytown , NY 10591-5153 For faster service, call (914) 333-2578 or FAX your order to (914) 333-2570 All book order> must he prepaid Please Include $5 00 shipping and handhng for dehvery of each book \1141 liP S In the U ~ , SIO 00 for each book shipped express to Canada . and $2000 for t"'a ch book "ihlpp<.-d expre~ co all other countries
urounJ
cuu/ /'ml,.!un dnilUJ i1!!!
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QUALITY ElfGROPLATIN6 EQUIPMENT Engineered ~Ylteml and Componenn for Metal finilhing APPLE FABRICATION COMPANY QUA LI TY
EL.ECTRO~nHO
EOUIPItIENT
815 Mercury Ave.. Dallas. Texas 75137 Phone: 972-298-9898 Fax: 972 -298-8474
Fig. 3 . Pad outlets. Weld "D" is the same as "A," except penetration is not required. Drill two lis-in. diameter holes, 180·apart, through weld for vent. Weld "E" plate must be bevelled distance equal to thickness of tank wall. Weld is to be built up above the surface of plate. peened and ground smooth and flush with plate . compressive strength after 28 days; smooth. monolithic interior free of ridges, depressions, honeycomb. fonn marks . etc.; freedom from contaminants and additives. i.e.• form release agents. air entraining agents. etc.; and hydrostatically tight and waterproofed on the exterior if located below grade. Self-supporting plastic and stainless steel tanks must comply with similar structural mandates as those enumerated for carbon steel and Portland cement concrete.
Polymer Concretes Polymer concretes are a generation of materials that have rapidly matured because of their outstanding chemical resistance and physical properties. They are not to be confused
Inside Tank
.p Fig. 4. Corner of rectangular tank. Weld "F" should be burned into plate so welds meet from opposite sides. thereby excluding air pockets . Welds must be peened and ground flush .
.:~£T.n.
K'SS~_=sJ °Go
Fig. 5. Butt joint. Weld "G" to be laid in V in beads not exceeding 31J6-in. deep After "G" is built up above plate on outside, the inner surface must be gouged out sufficiently to remove all scale and slag. Weld "H" is to be built up above the surface ofplate. peened and ground flush.
670
Table I. Typical Physical Properties of Polymer Concretes Tes/ Me/hod
Property
ASTM ASTM ASTM ASTM ASTM ASTM
Tensile strength. psi (MPa) Compressive strength.psi (MPa) Flexural strength , psi (MPa ) Linear shrinkage. % Density. Ib/fl3 Water absorption, % Maximum use temperature. ' FCC) Continuous Intermiuent Thickness. in. (rnrn) 1l1e chemical resistance of polymer concretes
C 307 C 039 C 580 C 531 D 792 C 413
Typical Value 1.000-2.000 (7-14) 10.000-12.000 (70-&2) 2.000-4.000 (14-28) < 0. 1 130--145 (2.1- 2.3) < 0.1 150 (66 ) 200 (93) 0.5 (13)
IS
similar to their synthenc resin lining systemcounterparts as mdicated
In
Table VII.
with portland cement concrete or polymer-modified Portland cement concrete, The only similarity to portland cement concrete or polymer-modified Portland cement concrete is the use of properly graded and sized aggregate in order 10 optimize workability and physical properties of the composition. P?lymer concretes utilize inert siliceous aggregates with binding systems based on such resms as furan, epoxy, polyester, vinyl ester, and acrylic . (See Table I for typical physical properties of polymer concretes.) The advantages to be derived from polymer-modified Portland cement concrete when compared with portland cement concrete are:
1. 2. 3. 4. 5.
Permits placement of concrete in thinner cross-sections. Excellent bonding to existing concrete substrates. Increased impact resistance. Reduced porosity. Faster set and cure. 6. Improved resistance to salt. It does not improve resistance to chemicals.
polymer modifiers are generally based on various resins and latexes. such as natural rubber. styrene-butadiene, acrylic . polyvinyl acetate, epoxy. and urethane.
LININGS There are a host of lining matenals available for protecting concrete and steel. The three ic types are glass-fiber-reinforced sheet and molten asphaltics; sheet rubber, plastics, and ~Sstomers; and reinforced and nonreinforced ambient-eured synthetic resin systems. e a ConspicuouS by its absence from this list is protective coatings. This is not to say they 'I be used; however, 60 mils is usually considered 10 be a minimum acceptable thickness ~: a maleriallo be consid:~ed a tan~ lining . If a co~ting can be .economically applied (initial t and longevity) 10 a nummum thickness of 60 mils, free of pinholes and holidays. and can co~ t the process chemicals and temperatures as well as physical abuse, consideration should restS . e fume and splash protection and be iven to their use. GeneraIly spe akimg, coatmgs are use d lor gl ecessarily for total immersion process applications. not nAsphaltic linings . . i or app I"icatron to concrete and steel. The are equ all y appropnate 'ed molten materials, as well as sheet stock can be used on concrete tanks For steel ppll hot-a ' . . the most desirable. ' ' k glass_fiber-remforced sheet IS Both types of asphaltic linings, sheet t~ s, olten, are seldom, if ever, used without being further protected with a chemical-resistant an. k~jning. Without further protection from a brick sheathing, these linings can cold flow and bric "b ' . M asonry sheathings be easily damaged from Impact, a rasion, an d th erm aI excursions. b
671
Table II. Physical Properties of Asphaltic Linings Value
Properly Softening point. ' F r e) Ash. max .. % Pene trat ion 77'F (25T ). 100 g-s-Ssec .
II S"F (46·C). 50 g-5sec. Chemical resistan ce
Type A
TypeD
200-225 (93-107)
250-275 (121-135)
0.5
O.S 18
38 75
27
Very good
Very good
provide a rugged. chem ical-resistant insulating barrier for protection of asphaltic as well as other Iypes of linings. The physical properties and the chemical resistance of asphaltic linings are shown in Tables II and III. respectivel y. Adhesive-bonded sheet linings, such as various plasticized plastics. rubbers and elastomers are most commonly used for steel tanks. Successful applications have been made on concrete: however, it is not the most desirable substrate on which to bond and cure many of these systems . The physical properties and the chemical resistance of sheet linings are shown in Tables IV and V, respectively. Mechanically bonded rigid plastic linings/or precast and poured-in -place concrete tanls are a relatively new conce pt. Instead of bonding with adhesives. this system utilizes anchor studs sonically welded to the back of the sheet for locking or mec hanically bonding the sheet to the concrete. Ambient temperature-cured. spray- and trowel-applied synthetic resin lining systems are based on the fo llowing resins: furan, epoxy. polyester, vinyl ester, and urethane. The se systems are entirely appropriate for application to steel and concrete. They have also been successfully applied to wood, certa in plastics, and various metallic substrates. These
Table III. Chemical Resistance of Asphaltic Linings M edium
Alum inum salts Cadm ium sa lts Chromic acid. 10 10% Copper salts Gold cyan ide Hydrochloric acid Hydrofluori c acid Iron salts Magnesium sa lts Nickel sa il.'> Nitnc acid . 10 20% Perchloric acid Phosphori c acrd Sodium chloride Sodium cyanide Sodium hydroxide, to 30% Sodium salts Sulfuric acid, 1050% Trichloroethylene Trisodium phosphate Zinc salts
Type A R
R
R R R R R
R R R R
R
C
C
R R
R R R
R C
C
NR R R R
NR R R R
R
R
R R NR
R R NR
C
C
R
R
C. conditional: R. recommended; NR. not recommended.
672
Type B
round tankl
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FIIJC
IIACI(ID.~~.",,'ff:l"raAlt•
••••••••••••••••••••••••••••••••••••••••••••••••••••• The Chemical Analysis of Electroplating Solutions by T.ll. Iroine
182 pages
$75.00
Chapters in this work are divided int~ _woup.< in al::ordancc with the penodtc table of ell" rnenlS. 11lough the procedures are traditional, theoretical aspects are included with other information. Anyone who studies this book carefully will derive a helpful undcrstandinR of what he or she is doing so that unexpected results can he searched out for cau10CS and mm'('1l'd Send Orders to- METALFINISIIING, 660 White Plains Rd., Tarrytown, NY 1OS91-'i1'i3 For faster service, call (914) 33.}-2';7fl or FAX your order to (914) 333-2'i70 All blK'k n,der,. must he prepaid. Please inc!ude $~ .OO shippinll and handlinll for ddivcry of each h,.,k vill UP~ In the U.S , $1000 for each book shipped "xp,,,,,"' In Canada. and $lO.OO fo' ,'a,h lx••k shipp,-d expres.'" to all other countnes.
Tuble IV. I'hy slcal Propt'rlles or Sh ed Lin ings rt'mpt'raturt' Rrsistunr«
Max.. "F (t:J
Chemica! Ru;stullft
1 ~ (66)
Verygood Verygood Verygood Verygood Verygood Very good
Nutural rubber Sufi Scmihurd IInnl Neoprene 8alyl ",hller Chloruhulyl rubber Polyvinyl chloride 1'lasliciU'd 1'1w.lici,.t"d rigid (2 ply) Chlon.."lfunalcd polyethylene T·' aurllcdfl'un.
1110 (!l2) 180 (82) 180 (112) IMS (8S ) 18S (MS )
Elcellent Elcellent Very good Em: llenl
1~(66)
I SO (66) 275 (135) 450 (232)
lining systems utilize such filler reinforcements as fluke glass and mica. Fabric reinforcements such as fihcrglass arc the most common; however. synthetic fabrics are used where Iluorides are present, These linings are extremely versatile and can be applied by maintenance personnel with skills in the pninling and masonry trades, Most manufacturers of these lining systems provide training programs for plant maintenance personnel. The physical properties and the chemical reslsnmce of umbient-cured synthetic resin lining systems are shown in Tables VI and VII. respect ively, Table V. Cheml cal Resistance or Shed Lin ings M..J,um
Alununum IllIIiI Cadnllurn .nhl Chmrmcacid. 10 IO'J, Copper ...h. Gllid cyanide Ilydrochiurie acid lIydmnlluric acid Imn . aU. MlIgneliulll oalll Nickel ...h. NllflC acid. 10 211':¥o Pen:hloflc acid 1~l mllh"flc acid Sud/urn chloride Sodium cyanide Sodnnn hydrolide, 10 30% Sotliarn lIlIlls Sulfuric acid. 10 20% Tnchloroeurylene Trisodium ph""phllle
Zinc oulla
'"
R R NR R R R R R R R NR NR
R R R R R R NR R R
R. rc'C'nmmtndcd. C. CondlllOJUlI: NR. not m:ommcndcd.
2
J
4
j
6
R R NR R R NR NR R R
R R NR R R R R R R R R NR R R R R R R NR R R
R R R R R R R
R R R R R R NR R R
R R R R R R R
R
NR NR
R R R R R R NR R R
R
R R R C
R R R R R R NR R R
R
C
NR R R R
R R R NR R R
'I • nUland ruhhcr-llil In,dcI; 2 • Neap~n. : J • Bulyland chlorobulyl; 4 • polyvinyl chloride; S • chlorooulfonal
674
R
R R R R R R R R
R R R
R R
Table VI. Physical Properties of Ambient-Cured Synthetic Lining Resin Systems Temperature Resistance" Max .•
Type
FCC)
Chemical Resistance
125 (52) 160(71) 180 (82) 160 (71)
Furan Epoxy Polyester Vmyl ester
Excellent Very good Very good Very good Good
150 (65)
Urethane 0Suggested lmut Without a masonry shealhmg.
The tables shown above all provide the design and corrosion engineer with basic information on the various lining systems discussed. They identify specific corrosives encountered in various metal-finishing operations. Enumerated are each of the various types of linings and a general recommendation for its use in the particular medium. It is recommended that the acceptability of specific linings, in specific media, be verified with the manufacturer.
Chemical-Resistant Brick and Tile Linings Historically, chemical-resistant brick and tile linings go back approximately 100 years, paralleling the development of sulfuric acid, various dyestuffs, and explosives. The use of masonry construction has grown in the basic steel, metal-working, and metal-finishing industries. Chemical-resistant masonry sheathings are not to be construed as hydrostatically tight tank linings. They are, in fact, porous, and consequently must be Table VII. Chemical Resistance of Ambient-Cured Synthetic Resin Lining Systems MedIum
Aluminum salts Cadmium salts Chromic acids, to 10% Copper salts Gold cyanide Hydrochlonc acid Hydrofluonc acid Iron salts Magnesium salts Nickel salts NItric acid. to 20% Perchloric acid Phosphoric acid Sodium chloride Sodium cyanide Sodium hydroxide. to 30% Sodium salts Sulfuric acid. to 50% Trichloroethylene Trisodium phosphate Zinc salts
r
2
3
4
5
R R NR R
R R NR R
R R R R
R
R
R R R R R
R Rb R
R R R
R R
R
R R R
R R C R R R C R
R
R
R
R
R
R NR NR R R R R R R R
R
R
R
NR NR R R R R R C NR
R
R
NR R R R R R
NR R R R R R R
R
R
R R C R R R Bis A Type R R C Bis A Type
R
R
R
R
R
NR R
NR
R
R
R
R. recommended: C. condmonal; NR. nol mcommended. "l = furan, 2 = epoxy: 3 = polyester. 4 vmyl ester. 5 = urethane 'Carbon filled matenals and/or final apphcallon willi syntheliC fabncs.
=
675
Table VIII. Chemical Resistance of Structural Plastics M~dillm
Aluminum salts
Cadmium salts Chromic acid. 10 10% Copper ,all' Gold cyanide Hydrochloric acid Hydrofluonc acid Iron salts Magnesium salts Nickel salts Nitric acid. 10 20% Perch loric acid Phosphoric acid
Polyvinyl Chloride
Polyethylene
Polypropy/~nt
R R R R R
R R R R R
R R R R R R
R
R
R R
R
R
R
R R
R R
R
R
R
R
R
R R
Sodium chloride
R
Sodium cyanide Sodium hydroxide. 10 30% Sodium salts Sulfuric acid. to 50% Trichloroethylene Trisodium phosphate Zinc salls
R
R C
C
R R R R
R R R R R
R R R
R R
NR
NR
R NR
R
R R
R R
R
C, condihonlll; R. recommended, NR. not recommended.
con~idered as chemical. physical, and thermal barriers for protecting membranes installed
~hJnd these sheathings. Brick sheathings contribute to the longevity of tank linings by
nlfe~ing additional chemical, thermal, and physical protection. They are excellent insulating
barriers and, consequently, can be considered as energy savers.
PLASTIC TANKS AND LININGS There are a multitude of plastics available for solving corrosion problems in the metal-finishing industry. The more popular and cost effective are polyvinyl chloride (PVC). Type I; polypropylene (PP); linear polyethylene (PE); and fiberglass-reinforced plastics (FRP). All of these plastics have been successfully used as self-supporting tanks and "drop-in" tank liners for process and storage applications. The thermoplastics (PVC, PP. and PE) are being used for mechanical bonding to concrete for similar applications. Polyvinyl chloride is one of the oldest proven plastics for fabricating highly chemicalresistant structures. (See Table VIII for the chemical resistance of structural plastics.) Type I PVC is one of the best plastics available for resistance to a multitude of strong oxidizing environments up to its thermal limitation of approximately l50'F (66'C). Type I PVC has outstanding structural integrity attributable to its high tensile, compressive. and flexural properties. It is one of the easiest plastics from which to construct tanks. tank liners, dipping baskets, and other storage and process equipment. PVC is easily thermoformed. cut. drilled, tapped, machined. and welded, consequently, making it an excellent, versatile, and cost-effective material from which to fabricate corrosion-resistant equipment. Polypropylene has arrived. Its popularity is attributable to its excellent chemical resistance and surpasses PVC because of its superior physical and thermal resistance. It is available as name and nonflame retardant homopolymer and copolymer sheet stock. Polypropylene utilizes fabricating techniques similar to those used for PVC. Small tanks for
676
pickling and plating. large tanks for continuous strip pickling lines. and pickling line covers have been fabricated of polypropylene. These and similar fabrications are enjoying an enviable record of success in challenging chemical and physical applications. Linear polyethylene fabrications have performed well in the small-parts metal-finishing industry because of their low absorption. high chemical resistance. and outstanding resistance to impact. They do not possess the rigidity and flexural capabilities of PVC or PP and. consequently, the fabrications are significantly smaller. A new generation of PE is making significant inroads into the finishing industry. Crossli~kable, high-density PE for rotational molding is being used for tanks of 5-10.000-gal capacity, These new resins exhibit excellent physical properties and good resistance to weathering. Applications for the most part have been indoor and outdoor storage tanks and portable receiver tanks. Fiberglass-reinforced plastics have been successfully used for a multitude of applications for many years. The earliest fabrications utilized furan and phenolic resin binder systems. The more popular resin binder systems in use today are polyester, epoxy, and vinyl ester. The success of FRP structures is substantially predicated on the proper choice of resin and hardener system most inert to the environment to whiqh the fabrication will be subjected. It is not enough to request an FRP tank. any more than it is to request a flake-glass-reinforced polyester tank. It i.s impo~t to either provide ~he fabricator with all chemical, thermal. and physical information pertinent to the. process 10 or~er that the proper resin and hardener system might be selected. or to have in-house technical competency capable of making the proper selection of the resin-hardener system from which the manufacturer can fabricate the desired equipment. There are numerous polyester resins available; however, for aggressive corrosion environments. such as high concentrations of alkalies and a broad range of acids, the bisphenol-A fumarate resin is the best recommendation. Vinyl esters are epoxy-resin-based, thermosetting resins that provide chemical resistance similar to that of bisphenol A polyesters. They are considered to be slightly better in high concentrations of.alkaline hy~ochl.orites th~ the bisphenol A polyester. Vinyl esters exhibit ou~tanding physical properties, r.e., tensile, flexural, and elongation that are normally associated with epoxies. The chemical resistance and physical properties of epoxy resins are functions of the resins. but equally important, they are .very much functions of the curing systems employed. Aliphatic and aromatic amine cunng systems impart better chemical resistance to epoxy resins than do polyamide curing agents. Polyamides, however, impart better impact resistance to epoxies than do aliphatic or aromatic curing systems. The intention of these three examples of the resin systems utilized for constructing fiberglass-reinforced tanks and t~k linings is to point out the necessity of knowing the chemistry of the system. or relying on reputable manufacturers to provide the technology required to make the best selection to ~ulfill end use requirements. Where the chemistry of these various systems contributes substantially to the physical properties of the structure. the most profound influence on physical properties is derived from the proper design and use of various reinforcing mediums, i.e.• glass fibers, glass cloth. roving. mat. veil. etc. Cons~lt reputable manufactu.rers for proper design consistent with the douse mandates for chemical, thermal. and physical properties. en The chemical resistance of FRP is comparable to the chemical resistance data shown in Table VII. Table ~IIl summarizes the che~ic~1 .resistance of P~C. PE, an~ PP. The mechanically bonded thermoplastic lining system previously described circumvents many of the limita~ion.s .inherent in some pl~stics, as well as coating. and many other elustomerie and resin Ilning systems. The s~mcally wel~ed anchor studs are of the same lustic as the sheet and ~ placed ~t .a~proxlmalely 2-3 m, on centers. Sheet thickness and p nor stud density provide the rigidity necessary for a successful thermoplastic lining anc li cation. The studs. being of the same plastic as the sheet, ensure thermal and physical app I .., Th e I'mmg . sys tem . f or new and eXisting . . concrete, . as properlY slmllanty. em iIS equaIIy appropnate
677
well as for salvaging used steel tanks. Upon removal of the concrete forms and the welding of all joints, utilizing thermoplastic welding techniques. spark testing is used for quality assurance of the lining. The system is available in a single- or double-wall system to ensure compliance withthe most rigid of environmental mandates. Leak detection systems are available and are integral with the lining system.
FABRICO TANK LINERS FOR TOTAL LEAK PROTECTION.., Prlll1llry Contalnm.nt 1 ForPlating T.nka Fabrlco Lintf1118 QlSlOm lIesigned 10 1M lht dimensions ofyour tank. They provide &xcell.nt resistance 10 COIIOSIvt attack bypla~ng solutions and oxidizing ,gentl.ln,tlllatlOn II quick and easy andcan usually be don.by your maintenlll1C8 peopl•. Fabrico Lintf1 can meet EPA guldlints,save you money, require less maintenance and stop hazardous leaks.
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Tank liners, floor liners, and secondary containment liners are our speciality Emergency fabrication service available at NO EXTRA CHARGE I,w n
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678
Top Quality (NASA is a customer) for over 25 years. .040" to 3/16". clearor colored material. Order before noon and get same-day shipment byair. Custom fabricated to any size or shape for steel or concrete. Teflon skirt availabhi"forchrometanks.
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secondary Containment Under Plating Lln.a This is aneffecbve melholl ofIOtal lIak protection. FabncO Tank Liners offer mora solutions toyour most compiicatad conlaJnment problems. WIII.O, C1I1Today Free Guide ToContainmenl Fabnco Envllonmental LJners,Inc.. 4222 South Pulaski. ChicagO, a. 60632 Phone (773) 890·5350 ToO Free (800) 621·8546 Fax (713)890-4669
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