Document 063no3d9Ve6rmXaJMK1LzvQzx

LEAD INDUSTRIES ASSOCIATION, INC. 2*2 MADISON AVENUK O NEW YORK* N. Y. 10017 mi^HONI -- AMCA C00I 111 0 MOM May 3, 15^5 SUBJECT: NEW TANK LDfDIO METHOD To Members of the Lead Industries Association, Inc.: Attached la a copy of an article describing a nev method of apply ing lead linings to chenlcal tanks, which appeared In the March 15th Issue of CHEMICAL ENGINEERING. It vas baaed on information gathered by the lead Industries Association staff and presented earlier In an Issue of LEAD, which appeared in December, 196k. The method described Is mere or less experimental, as we know of only one prior Installation using this Dethod. Since both of these In o stallations have proved successful to date and since the method Introduces rather substantial savings In applying lead linings. It may place lead In a better competitive position and offer opportunities for expanding the market for lead In chemical installations. Members cay obtain additional copies In quantities up to 25 free of charge and larger quantities at our cost of &4 per copy. Very truly yours. RLE: ok Ene. Executive Vice President a n -- r irt LIA23378 -------- ----------------------a - -` '--HT1I r,J1> ih'l-fufl M CHEMICAL ENGINEERING REPRINT Use Epoxies to Line Tanks with Lead Oiltributtd bjr Lead Industries Assoc.iaflan,Ine. 293 MADISON AVENUE NEW roKK. -V. Y. 10017 i. N 1704.01 0+m* 1 'fw11 Corrosion Forum LIA23379 \ Lead-Hard sulfuric acid storage Unki at Martinet, Calif, plant f Tidewater Oil Co., described ia this article. Use Epoxies to Line Tanks with Lead U'hrn lead is bonded to lank walls with epoxy adhesives, lighter sheets can be em ployed and considerably less lead welding (lead burning) is required. When tanks have to be lead`lined, a new technique that employs adhesive bonding may offer substantial saving*. In the conventional method of lining tanka with lead, the metal is supported on steel straps bolted to the inside of the tank. These straps are covered with lead strips, and the lead lining is welded (or "burned" In lead-wurker's terminology) to the lead atrip*. Thus, the interior of the tank present* a aurface that ia entirely of lead. However, aince the lead lining is supported by the strap* at Intervals only, it must have sufficient structural strength to support itself in the apace* between the straps. When the lead sheet is bonded to the tank wait by an adhesive, the sheet need be only thick enough to meet corrosion requirements. The Installation of such a lining, pictured in this article, took place at the Tidewater Oi! Co** refinery at Martinet. Calif. There, fhe storage tanks required relining after **x and a half years <>f exposure to acid sludge. The sludge consisted f sulfuric acid and hydrocarbon product*, and came from the treat ment uf aromatic solvents, light lube oils and kerosene during the refining process. Previously the tanks (which were originally Installed in 1911) had been lined in the conventional way with 10< and 12-lb./*q. ft. lead linings that were hung in the tanks by straps. Engineers at Tidewater decided to use a new technique of bonding the lead directly to the steel tank by employing an epoxy adhesive. The technique was used nn three of the five tanka. (A simitar installation was made several year* before *t the plant of Shell Chemical Co. at Wood River, HL) Since the steel structure would support the weight of the lead, the designers determined that they could use lead sheet weighing G Ib./sq. ft., instead of the previous 10- and 12-lb. weights. This thin, A-In. sheet saved almost 60c in the cost of the lead. 'ic'alting the Lining First, the steel shell was sandblasted to remove scale and oxide. In a new installation, the sand- ItcprJfHnl from MIE.VIC.tl. EVGI.NFKRINC, Mar. IS, IMS C*T1X1 W HHinv.lllR. In#. IJ9 W-. It Si S# Vi.ik. N Y. loose 1 O COttOSKX POtVM . . . Lr^?3380 *i Adhesive U applied to Irad hsct (on form! and to sandblasted sirrl-urk h*11. Form U raised against tank wall and braced in pUr** f*>r curing p*-nL After uru-.g. l.rarrs arr rt-m*vrd prrp.ratorjr to removing form. Adjacent section of rterl tank has bevn sandblasted and i* ready for application of the next sheet. o Q Masting *tep would probably also be required to remove mill scale aa writ as rust. Only a few sections of the tank were cleaned at one time. *n that they would remain clean tong enough for the lead bonding to t*e done. Second, all the b*dt M-V-* remaining frm the previously u.-cd !ra|>* rtr plugged nilh adhesive. Of course. such a procedure would not be required with new tanka. llonding the Uid Sheets Preparatory to installing the lead, one aide of a sheet was wire-bru*hrd to prepare it for the ad* he*ive. The adhesive applied *a Shell Chemical Co.* Epon 901-B. Thia ia an epoxy that cure* overnight at 7o F. and will withstand service temperature* up to 225 F. Adhesive wa* applied while the sheet was lying on a specially prepared form, curved when needed to match the interior of the tank, and covered with foam rubber. Workmen then applied adhesive to the tank wall at the place the sheet was to be installed. At this point, the form holding the sheet was raided a<> that the adhesive on the sheet came into contact with the adhesive on the wall. The form waa braced In place, and the epoxy adhesive waa cured for 24 hr. before the from and its brace* were removed. WeldUg (he Seams Each sheet waa overlapped on the preceding one by 2 in. Finally, the long vertical seam at the overlap waa welded by conventional kadhurmng techniques. The overlap waa used to prevent the welding opera tion from dMtnMginf the adhesive bond. The rnlire lead installation wa* handled try Western LeaJbuming Contractor*. C<*mord. Calif. In addition to the vertical seams, lead welding w a * needed ,n the bottom sheets and at the juncture of the aide and bottom. Oj the three tanka that were lined by thi* new me*.hd. one is 20 ft. nix. w.th 12-fL-high walla and a lead -urface of 1.120 *q ft. The second is 20 ft. dia., with 10-ft.-hiyh vertical will* and a 6-ft.-deep '-onicat bottom, ft has a surface area *f 2,415 *q. ft and was originally lined with 10 Jb *q. ft. lead no the vertical walls and 12-lb. lead on the cone. The third tank U rectangular. 20 ft. by IS ft., has 6-ft.-hifh walla and contain* 720 *q. ft. of lead. Advantages Several advantage* are claimed for this new leadlining procedure. Thinner lead sheet l* needed since th lead U entirely supported by the steel ihelL Much of the lead welding ordinarily required Is eliminated. The adhesive bond cannot be damaged by weathering. The adhesive is sufficiently resilient to maintain the bond even under the differential expansion of the lead and steel caused by environmental and process temperature changes. Key Concept* for This Article \*H%* l*| fntft(l(Af r*brt. all.* A|M`rt PsM* < l.lftlAtf Ur*4 A* < nrt , rriln* <!) (N'oHi Ia hoi4 as* s**l* Ali*>K tAArltna numh*rt mrr*apvn4 U -- A IA Ckfa ga0, Jtn 1. J)*J. * J> *n vtlUbl, mm KraUrr I