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FILE NAME: Oil Industry and American Petroleum Institute (API) DATE: 1952 Nov 3 DOC#: API087 DOCUMENT DESCRIPTION: Trade Journal Article by E.C. Sherman - Industrial Thermal-Insulation Application NEXT WEEK New Unit Really Cleans Tube Bundles. P c t r o c h e m Report: Neches Butane Products Co. and Gulf Oil Corp. Direct Determination of Bottom-Hole Pressures. Drill-Pipe Rejects Show Good Service Life. How to Join Different Sizes of Pipe at Odd Angles. Oakford Project Dehy dration Plant. Automatic Tank-Gaging Facilities. Radioisotope Tracer Suc cessful in Products Pipe Line. Automatic Flash-P o i n t Instrument. REGULAR DEPARTMENTS They S a y ........................... 53 Calendar of Events 54 Journally Speaking 59 Editorial .................................... 61 This W e e k ............................... 63 Watching Washington 76 International News 80 Personals .................................. 85 Deaths in the Industry 87 B ooks............................... 112-116 On the J o b ............................... 125 Engineering Reference 129 Modern Drilling ..................131 Heat T ra n sfer........................... 132 Refiner's Notebook ............... 133 Engineering Fundamentals- 135 Progress in M e ta ls................... 136 Pipe-Line Construction . 137 Pipe-Line N e w s ..................... 144 Natural-Gas News 147 Natural-Gasoline News 147 Refining N e w s ............ 148 Drilling Contractors ISO Active Rotary Rigs ............... 150 Exploration Statistics............... 168 Production Statistics ............... 169 Refining Statistics ................... 170 Market Statistics . 171 Equipment Men in N e w s........ 175 Classified A dvertising............ ' 178 Advertisers' I n d e x ............... 181 EXPLORATION DEVELOPMENT Williston S k etch es...................... 153 Highlights of Week ..................153 Reports by A re a s ..................... 154 N O V E M B E R 3, 1 9 5 2 ..... V THE OIL AND GAS J O U R N A L Voi. 51, No. 26 CONTENTS FOR NOVEMBER 3, 1952 NEWS FEATURES CO' Solution in Flooding Brings Higher Oil Yields, Group Told 64 Electric Current Through Oil Sands May Raise Production ......................... 64 Reservoir Types Determine Success or Failure of Wetting A g e n ts ............... 65 Economics of Dehydration Processes Discussed by N.G.A.A. P a n e l.......... 66 Oil Discovery Indicated by Deep Test in Delaware B a sin ............................. 66 Proration Dilemma Facing Texas and New M ex ico ........................................ 67 Northern Natural's Growing Pains Typical of Industry's Problems .......... 69 U. S. Can Produce Enough Oil to Meet Needs Without Imports, I.P.A. Says 70 United States Pipe Line Co.'s Project Partially A m ortized............................. 71 Gas-Utility Industry Warned to Promote Product, Continue R esea rch .......... 72 Added Gas Research Is Needed, A.G.A. Told .............................................. 73 Westby Accepts as Head of I.P.E. Selection Committee ............................. 74 Benzene Market to Remain, But Substitutes May Curtail Demand .............. 74 Companies Ask Supreme Court to Review Rulings in Cartel Case . 75 Alkylate Output Up to 10,000 Bbl. D a ily ........................................................ 76 Oil-Country Tubular Goods Allocated for First-Quarter Operations 76 NPA Takes Over Control of Tubular Goods Made From Imported Steel .. 76 Socony Sets Up New Exploration, Production Division at C a sp e r................. 79 Fabulous Gas System Proposed From Iraq Fields to Paris , . .8 0 Workers, Employers Divided on Cut in Work Hours; Study A sk e d ............ 83 ENGINEERING-OPERATING FEATURES Southern Natural Removes Distillate From Pipe Lines ....................... 88 Pipe-line efficiency is increased by injecting absorption oil into field lines. By L. N. Brown and J. M. Phillips, Southern Natural Gas C*. New Procedures in Industrial Thermal-Insulation Application ........... 90 New application techniques, development and prefabricated shapes drasiically reduce installed cost of insulation. By C J. Kuhasz and E. C. Shuman. > Low-Temperature Insulation for Refinery S ervice............................................ 99 High cost of obtaining and maintaining low temperatures demands best of in sulation practices. By W. L. Martin, Humble Oil & Refining Co. Water Flooding in Kansas' Golden Lane ....................... 104 Performance data and field report on 32 water-flood projects in Greenwood County, Kansas. . How to Cope With Crooked-Hole P roblem s.................................................... H I Large drill collars, two-cone bits, and stabilized drill-collar strings used to straighten hide. By Gerald Burgess, Ohio Oil Co. Where Will Tomorrow's Oil Come From ....................................... .. ........ .. 119 Yet-to-be-discovered deposits of oil should meet world's petroleum needs for long time to come. By E. V . Murphree, Standard Oil Development Co. On the Job . . . la the P la n ts ............ ................................................................ 125 Tennessee Natural's control of outlet regulators. On the Job . . . In the F ie ld s ............................................................................. 126 Connecting into a full Hoc. ' Engineering Reference Section ........................................................................... 129 Modern Drilling ................................................................................................ 131 Heat Transfer ............................................................................... 132 Refiner's Notebook .................................................................... 133 Engineering Fundamentals ............................... 135 Progress in M etals ................................................................................................................. 136 1 A T TA 4 b PLAIN BLOCK 1t .......... + TEE SHIP LAP BLO CK CAP Fig' 1--Some of the shapes used in the new insulation method. NEWPROCEDURES IN... Industrial Thermal-Insulation Application Thermal insulation is required in many refinery applications, where temperatures vary from the very low values used for re frigeration processes to the very high ones encountered in furnace operation. These two articles, one on high-temperature insulation and the other on low-temperature insulation, bring together a number of pertinent facts on this important subject. New methods, mate rials, and concepts are highlighted. by C. J. K uhosz and E. G. Shum anf lt/TETHODS have been developed 1 which drastically reduce the in stalled cost of thermal insulation. These include not only new applica tion techniques, but also the develop ment of prefabricated shapes which re duce cutting and forming in the field to a minimum. Advantages are (I) greater economy, (2) a saving in the amount of critical material required, (3) greater durability, and (4) elimina- *Development engineer, the M. W. Kellogg Co., New York. tDirector of research, Kaylo Division, Owens-Illinois Glass Co., Toledo. Presented at the Petroleum Mechanical Engi neering Conference, Kansas City, Mo., Sep tember 1952, of A.S.M.E. tion of the confusion resulting from the use of various grades and thicknesses of material. These methods have been employed on three projects now in operation, with savings of $50,000 to $250,000, and on numerous others currently un der construction. Savings run from 15 to 25 per cent of the cost based on previously used processes. Reduction in number of insulating joints varies from 200 to 700 per cent, while reduction in the number of sep arate operations required for an instal lation runs from 30 to 60 per cent of those formerly required. Former difficulties . . . Difficulties of older methods are concerned with the weathercoating, and are (a), failure of weathercoating at the joints between blocks under extreme elevated temper ature service due to heat infiltration, (b) , failure of bond between the insu lation and weathercoating due in part to materials and in part to moisture sat uration of the insulation by rain, and (c) , failure of weathercoating due to insufficient weathering and heat re sistance. To avoid such difficulties and to make the method as nearly foolproof us pos sible the following steps were taken: 0 THE Oil. AND GAS J O U R N A L (a) The design of joints for high tem perature service was modified to insure that the weathercoating reinforcement would not be strained excessively as a result of expansion of the metal to which the insulation is applied, (b) The holes for the attachments were counter bored and packed to eliminate any pos- sibility of over heating the coat by con duction through the pins, (c) All insu lation was prime coated on the outside before installing against metal surfaces, in order to minimize water absorption from unexpected rains which may oc cur before the weathercoat is applied on the job. General Description of Method . . . Using this method of installing ther mal insulation it is possible to apply insulation to the metal surfaces of ves sels, equipment, piping, valves, fittings, bins, duct work, etc., at reduced in stalled costs that are well below those of other methods, even though initial material costs are slightly higher. Insulating material . . . The method can be employed for all operating metal temperatures up to 1,200 F. while specifying one type of rigid insulation material known as hydrous calcium silicate in a single thickness. The den sity of this material is approximately 11 lb. per cubic foot and its average com pressive strength about 150 lb. per square inch. The material is insoluble in water, has a high wet strength, is incombustible and its handleahility is exceptionally good, resulting in a very small amount of waste. The material is supplied in 1 to 5-in. thickness in increments of Vi in., in the forms of flat and curved block and pipe insu lation. Shop Fabricated Shapes The bulk of the insulation material is shop fabricated in standard shapes and properly identified for field assembly. The size of each piece is predeter mined for ease of manhandling and minimum damage during shipment and erection. In general, the length of each piece is 36 in. and the thickness is eith er cast or laminated up to 5 in. For cylindrical surfaces of vessels, pipe, etc., the width of the curved blocks and the number of pieces around each circumference are determined by ihe diameter. In general, pipe insulation is supplied in two pieces for diameters from Va to 12 in., three pieces for 13 to 18 in., four to eight pieces for 19 to 40 in., and in nominally 18-in. wide pieces for diameters over 40 in. up to 60 ft. For irregular curved surfaces, such as heads, cones, transitions, etc., blocks of two types are supplied: (a), 18 by 33-in. hinged blocks made by adhering woven glass fabric to individual small blocks of triangular shape (the glass fabric provides hinging action and there is little danger of the pieces breaking apart), (b), 9 by 18-in. curved blocks with the direction of curvature determined for best fit of surface cov ered. A change in radius is dictated when the space between the inside of the insulation and the metal surface exceeds Vs in. For flat surfaces such as bins, ducts, etc., flat blocks are sup plied in widths up to 18 in. For pipe fittings, valves, flanges, etc., of the butt weld type for diameters larger than 2Vi in. and for flanged types larger than 1Vi in., standard pipe insulation is cut, formed and securely held together with a water and heat resisting cement and is supplied pre assembled weathercoated in two to four pieces. Pipe bends from 3 to 10 in. arc also supplied from standard pipe insulation. Insulation used on metal surfaces operating at temperatures below 700 F. have shapes provided with straight edges cut normal to the outside surface of the piece. For metal surfaces above temperatures of 700 F. the shapes are provided with Vi-in. shiplapped edges also cut normal to the outside surface. In addition all pieces for thicknesses of 2Vi in. and over are provided with a 30 bevel cut about % in. deep along all the outside edges. Insulation used on cylindrical, flat and irregular metal surfaces (except for cylindrical surfaces smaller than 24 in. in diameter operating below tem peratures of 700 F.) the shapes are provided with two to five shoulder holes properly spaced, except for hinged block in which a multiplicity of holes are provided. For pieces 2 in. in thickness and below, the shoul der of the hole is 1 in. high and for 2Vi in. and thicker is lVi in. high. For cylindrical surfaces 24 in. and smaller operating at temperatures above 700 F. each shape is provided with two shoulder holes. As an alternate type, straight holes may be used for thicknesses of 2 in. and smaller. In all cases holes are drilled normal to the outside surface of the piece. The small diameter of the shoulder hole is made large enough to admit a ceramic ferrule for a 3/16 or V*-in. diameter welding stud, with sufficient clearance to allow proper venting of gases during welding and to prevent scraping the sides of the hole and pick ing up particles of insulation. The larger diameter is made large enough to admit a welding stud bending or speed clip fastening tool. When the alternate straight hole is used its diameter should be the same as the small diameter hole of the shoulder hole. Regardless of operating temperatures and kind of metal surfaces insulated, the pieces are protected from moisture. This is done by either prime coating or weathercoating the outside surface of each piece prior to its erection. In general, insulation for cylindrical sur faces smaller than 24 in. in diameter and all pipe fittings, valves, flanges and pipe bends are furnished with a prime spray coat and a 1 / 16-in thick finished weathercoating applied before shipping. All other pieces are furnished with a film of spray coated water re pellent primer applied to the outside surface and the ends, also prior to erection. When the outside diameter of insu lation is greater than 16 in. it is rein forced with a layer of glass fabric when used for pipe fittings, valves, flanges and specialties. Some of the shapes used in the method described have been shown on Fig. 1. Field fabricated shapes . . . For pipe fittings, etc., of the butt weld type under 3 in. in diameter, flanged type under 2 in. and for screwed type over 3'/2 in., standard pipe insulation is sup plied for field fabrication. In addition to the foregoing, on every installation certain items must be con sidered as specialties and do not fall into the present range of standard shapes. In such cases the economics of shop against field fabrication must be taken into account. A limitation against diop fabrication usually is due to dam age of large assemblies in transit; in many cases, though, this can be over come by increasing the number of pieces and shipping them disassem bled. On the other hand, if field fabri cation is decided upon it will be noted that most specialties can be nude from standard pipe or flat insulation mate rials. Mineral w ool. . . Prefabricated mineral wool is available for pipe fittings, valves, etc., of the screwed type under 4 in. in diameter. Felted mineral wool blanket in 1-in. thick layers are supplied for pipe bends under 3 in. in diameter, and for pack ing construction cracks and openings. INSULATION SYMPOSIUM HIGH TEMPERATURE Reinforcement . . . Glass fabric is sup plied for reinforcing and should be made in an evenly woven mesh, im pregnated with a water resistant com pound that is not soluble in the sol vent in the weathercoating, in order to prevent possible damage to the glass fibres, which might occur if their coat ing is partially removed and friction between strands can be induced. The trend count should be no less than 20 per inch in both directions with a min imum strength of at least 60 lb. per inch of width and should weigh about 2 Vi oz. per square yard. Fasteners . . . Welding studs are sup plied in carbon or alloy steels in eith er the 3 / 16-in. diameter split pipe type or the '/-in. diameter solid pin flux or slug loaded type with a 1-in. diam eter metal speed clip, both types are furnished in lengths of 1Vi and 2 in. with ceremic ferrules for good welding. Welding studs must be suitable for use with a welding gun of the timed volt ampere type. Weatherproofing . . . Prime coat mate rials which do not introduce water into the insulation and are suitable for spray application are used to prevent rain from being absorbed through the sur face of the insulation. In order to ob tain a good bond for the weathercoat, the primer should penetrate the surface of the block and not be soluble in the solvent of the weathercoat. Weathercoat materials suitable for indoor or outdoor spray application are used, such as asphaltic, bituminous und rubber based. The type selected should be based upon the temperature condi tions to which the weathercoating will be subjected to, such as heat transfer, magnitude of joint movement and number of times the joint opens and closes in a given period. They should be moderately fast drying, flexible and resilient over a wide range of temper atures with a working temperature of at least 300 F., have good adhesion and good weathering properties and long life. Coatings should not support com bustion to an extent that they will spread fires that reach them. It must be recognized that many solvents are flammable, so that care is essential dur ing application and for a short time thereafter. No serious problem has arisen from this condition in the field. cause of excessive metal temperatures. This high temperature cement should be fast setting, have good weathering properties, low water absorption, good adhesion to insulation and metal, high coefficient of expansion to minimize checking and cracking, and when ap plied should be of troweling consist ency. Other commonly used materials such as metal wire, bands, cables, wire mesh, lacing wire, nails, sheet metal, plastic cements, etc., will not be described herein. Installing Insulation To obtain the best results during the service life of the insulation it is very important to adhere to the proce dure described for applying the mate rials to cylindrical, flat and irregular curved metal surfaces. In order to avoid entrance of water into the insulation, whenever practical, erection of the insulation should be started at the top most part of the metal surface. Around all irregularities projecting from the metal surfaces, pieces of insulation should be cut to fit neatly. All pieces are installed in such a manner that the flow of heat by con vection is minimized along the joints between adjacent blocks. For vessels, equipment, etc., set in a vertical posi tion the longitudinal joints should be staggered and the circumferential or transverse joints should be continuous. In the horizontal position the longitu dinal joints should be continuous and the circumferential or transverse joints should be staggered. In all cases the joints between adjacent blocks are butted together tightly. Cutting reduced . . . To reduce un necessary cutting and the number of joints, a survey should be made of the metal surface to be insulated, and the first row of pieces to be installed should be started with a longitudinal joint in line with the greatest number of pro jections which are on more or less a common centerline. Where shiplapped pieces are used for irregular curved surfaces, it will be found that some of the shop fabricated material will not always fit the curva- ture and it is necessary to do some lapping in the field. In such cases a mechanically operated tool has been used to cut the lap. Where hinged blocks are used, they should be cut and fit to conform as nearly as possible to the contour of the metal surface, and protruding edges should be pounded with a wooden mal let to form a reasonably smooth sur face. ' Insulation should extend beyond the straight portion of cylindrical metal surface a sufficient amount to allow good trimming to conform to the in sulation of heads, cones, transitions, etc. The void occurring at the junc tion of the shell and head insulation should be filled with waste block whenever additional stiffness is re quired. The object of individually support ing each piece of insulation is to con trol and localize to small increments the movement caused by expanding hot metal surfaces. The effect is to distrib ute the total metal expansion to a great number of positive joints between ad jacent blocks. For example, a hot metal surface with a circumference of 95 ft. 0 in., expands 4 in. to 95 ft. 4 in.; using 18-in. wide blocks, the joint be tween adjacent blocks opens up to 1/16 in. due to the expanding metal surface. Without individual support, it is conceivable for the insulation at some place to open as much as 4 in. Fastening insulation . . . In general, all pieces of insul.ition are firmly se cured to the metal surfaces with car bon or alloy steel welding studs, either of the split pin type embedded into the insulation, where the metal surface is comparatively clean, or the solid pin flux loaded type with a speed clip, where the metal surface is heavily mill scaled, rusted or painted. When the metal thickness is within the sheet metal range the use of welding studs may be prohibited, in order not to burn through the metal. In most cases, each piece of insula tion is manually held in place while at least two welding studs are fastened to the metal surface. This procedure may be continued for a number of Cement . . . High temperature plastic ccmcni materials suitable fo r tem p er atures up to at least 1,200 F. are used to prevent rain from being absorbed by the insulation in places where the use of weathercoat is prohibited be- Fig. 2--Installation of split-pin type of weld ing stud. ' Fig. 3-- Installation o( solid-pin ftan type of welding stnd. INSULATION S Y M P O S IU M - 92 HIGH TEMPERATURE THE OIL AND GAS J OURNAL blocks or all welding studs can be fas tened in each block before proceeding to the next block. The proper number of welding studs used to secure each block will depend on the position of the piece, such as overhead, vertical, etc. To install the split pin type welding stud, the pin with a ceramic ferrule is inserted into the shoulder hole and welded to the metal surface, after which the ends of the pin are bent over and embedded into the insulation by using a special tool designed for this purpose. Refer to Fig. 2. To install the solid pin flux or slug loaded type welding stud, the pin with a ceramic ferrule is inserted into the shoulder hole and welded to the metal surface, after which the speed clip is placed on a magnetized tool inserted in the hole and pressed over the pin until it bears firmly against the shoul der. Refer to Fig. 3. Packing holes . . . In general, after blocks are securely held against the metal surface, either a calcium silicate dowel or mineral wool is inserted into the hole. Where thickness of insulation is under 2Vi in., packing may be omitted without any detrimental effects. It is to be noted that only two lengths of welding studs are required regard less of the insulation thickness, one length for 2 in. and less, and one length tor 2Vi in. or over. The object of using the packed shoul der hole is to prevent the transfer of heat from the hot metal surface through the welding stud to the weathercoating,' thereby maintaining approximately the same temperature at the stud location as is over the entire area of the blocks. Applying Reinforced Weatherproofing Insulation and spray applied weath ercoating reinforced with glass fabric is comparatively simple to install when compared with conventional methods of using metal wire mesh and multilayer troweled on water bearing plastic cement and weathercoat, or sheet metal cover ing. It is to be pointed out that one of the most 'troublesome features and costly items of the conventional meth ods was the great amount of "water bearing plastic cements, which the method described has eliminated. In general, after blocks have been se cured to th e m etal su rface an d all cracks and openings larger than Vfc in. in width have been packed with mineral wool (normal joints between adjacent pieces of insulation will be sufficiently tight to require no packing), the reinforcing and weathercoating FIr. 4--Rtbiforctai wcatiwrrtwtlaR at taw- FIS. j--huteHattaa of lation Jofaits for (Mck tasatotion. proceeds as soon as practical without interfering with mechanics. It should be noted that when at any time the insulation cannot be com pletely covered with glass fabric, due to conditions in the field, the tack spray coat must be continued until it covers all the exposed surfaces of the insulation before leaving that area of work. The finish weathercoating should be sprayed over the glass fabric to a thickness which will dry to approxi mately 1/16 in. Where metal temperatures are above 300 F. the weathercoating should not come in contact with the metal sur faces, at such places a high tempera ture cement should be used. Preferably the finish coat should be applied as soon as practical, so that scaffolding can be removed and waste cleaned up as the work progresses. With respect to patent scaffolding it can be reused more often than heretofore and a smaller initial amount is required when compared with installing insulation by conventional methods. Glass fabric reinforcing should be cut into strips about 7 ft. long, and when installing, it should be lapped along all edges at least 3 in. Prior to installing' glass fabric it is important to see that the tack spray coat is wet, be cause if it is not there will be no ad hesion between the block and the glass fabric. When embedded into the tack coat the glass fabric should net be pulled tight or stretched, rather, it should be layed on the tack coat and pressed into it just free of wrinkles. In fact, some small wrinkling will be helpful as it will show some slippage of the individual glass fibers within the weathercoating. The finish weathercoating must be uniformly sprayed to a thickness of 1/16 in. over the entire area of the glass fabric in order to protect the fab ric against deterioration. Sealing Joints Between Blocks Reinforcing weathercoating for insu lation 2Vz in. in thickness and over should be applied to the joints between adjacent blocks, in the same way and, at the same time as the block surfaces. The glass fabric should be pressed into the tack coat and formed to the con tour of the notch and covered with weathercoating. Refer to Fig. 4. This type of joint allows the hot metal surface to which the blocks are rigidly fastened to move without put ting tension on the weathercoating, thereby keeping it free from cracks. The joint functions as follows: during the first heat up of the metal surface and as the metal expands the reinforced weathercoating starts to peel back from the apex of the notch, the peeling ac tion continues until the maximum ex pansion of the metal surface is reached. - Upon cooling of the' metal surface the weathercoating recedes into the notch. The only stress to which th e ' weathercoat is subjected to is flexing action caused by subsequent cycles of heating and cooling. For extremely high temperature w teUic surfaces a joint similar to the pre ceding one is used, except a heat re tardant seal of soft asbestos rope or its equal is inserted in the notch over the joint between the blocks prior to in stalling reinforced weathercoating. Re fer to Fig. 5. This type of joint is similar to that described above, except a heat retard- ' ant seal is furnished to reduce the transfer of heat by convection from the metal surface to the weathercoat ing, thereby keeping it free from cracks and embrittlement; furthermore, the seal will prevent charring of the weath ercoating. , Miscellaneous applications. . . Although the greater part of every project re quiring insulation consists of covering plain metal surfaces, there arc many places on vessels, equipment, etc., where special considerations must be employed to provide a satisfactory in stallation. Several of the most impor tant are described herewith. Weld seam lanes . . . When weld seams in m etal surfaces require periodic in spection, the seams are covered with: 6-in. wide single or 9-in. wide ahiplapped curved or flat blocks. In gen eral, the metal surfaces to within 3 in. of either side of the weld seam are in sulated and weathercoatcd first, form INSULATION SYMPOSIUM-- ---------- HIGH TEMPERATURE `; Ifteerr. * r h r i `. b- ..-v if ' .. ?' t; * I Fig. 6--Installation of inaoiation for a d d (earns. Fig. 7--Insolation of Fig. 8--Insulation of projections, w h i c h projections w h i c h tng a lane, after which the lane blocks are cold metal sur faces. are hot metal mrfaces. are placed in the lane and secured with welding studs. Reinforced weathercoat Insulation flashing. . . The top head of eling the ends of the block at 45 in ing is then installed and lapped at least vertical vessels should be provided with direction of drainage, after which a 3 in. over the permanent insulation. a rain drip properly flashed to the in piece of galvanized sheet metal flash When it is necessary to remove lane sulation. Refer to Fig. 9. The seal ing is extended along the-metal sur blocks, the weathercoating is cut along should be made by installing two layers face about 4 in. and along the surface the edges of the lane, welding studs opened, and lane blocks lifted from place. To replace, the same procedure for installing is used. Refer to Fig. 6. of glass fabric on the vertical blocks and then extending it over the knuckle curvature by at least 12 in. A rain drip made of galvanized sheet metal at least of the block for 4 in. The flashing should be fastened to the metal surface with a continuous metallic bead. Be fore flashing is installed the blocks Projections Through Insulation Where metal surfaces project through the insulation, such as nozzles, etc., which are below 300 F. The edges of the block adjacent to the projection 6 in. wide should then be installed around the curvature by nailing it into the insulation. The edge of the drip should extend about % in. beyond the vertical blocks. The drip should be covered with a layer of weathercoating, should be weathercoated to within 2 in. of the bevel so that flashing can be extended over it. Where insulation terminates on metal surfaces for temperature below 300 F., the ends of the blocks are flashed should be beveled at an angle of 45 extending over the head insulation. against the metal surface as described 1 in. deep on the inside. The blocks The heads of horizontal vessels above, except reinforced weathercoat should be installed by extending them should be finished as described above, ing is substituted for the sheet metal. to within Va in. of the projection and except the rain drip is omitted. These seals are to prevent water from firmly secured, after which the bevel and adjacent block, and 4 in, of the projections surface should be sealed with two layers of reinforced weather coating. When glass fabric is installed Where insulation terminates on the metul surface for temperatures above 300 F. the ends of the blocks are flashed against the metal surface. Refer to Fig. 10. The seal is made by bev- entering joints between insulating blocks or between blocks and metal surfaces, thereby keeping insulation dry, which in turn reduces corrosion effects on the metal surfaces covered. it should be pressed into the contour of the bevel and overlap the glass fab Straight and Bent Pipe Application ric on the block by at least 2 in. Refer In general, shop weathercoated in to Fig. 7. sulation should be installed on straight Where hot metal surfaces project pipe of 22 in. in diameter and smaller through the insulation, which are above and on pipe bends from 3 to 10 in. in 300 F., The edges of the block adja diameter. Depending upon metal sur cent to the projection should be beveled face temperatures, either weaihcrcoai- at an angle of 45 1 in. deep on the ed hinge block or 9 in. wide shiplapped inside and 45 on the outside. The curved pieces should be installed on blocks should be installed by extending pipe bends larger than 10 in. and on them to within 1 in. of the projection irregular metal surfaces. . For pipe and firmly secured, after which the bends under 3 in. in diameter, felted space between the projection and the mineral wool blanket in 1-in. thick block should be sealed by troweling it layers should be installed. It should full of high temperature cement, which be noted that shop weathercoated pieces should be extended along the surface of are optional for indoor application. the block for at least 4 in. Whenever practicable, insulation for Water should be kept off the cement butt weld fittings, valves and pipe bends for several hours to allow setting. After should be installed prior to the pipe the cement has dried a 4 in. wide strip insulation. Where flanged type fittings of reinforced weathercoating should be and valves are to be insulated, the pipe placed over the joint between the block insulation should be insulated first in weathercoating and the cement. Refer order to allow fitting and valve insula to Fig. 8. tion to extend over the pipe insula These seals are to prevent water from tion. . getting into the insulation and behind the weathercoating and, to decrease the transfer of excessive heat to the weath Installed loose . . . Insulation should be installed w ith re c o g n itio n of the de ercoating, thereby, overcoming crack Flg. 9--(Top) Rata drip dou ld he provided sirability of a specified degree of fit, ing, peeling, embrittling, loss of resil for top bead of vertical vessels. and adjusted to be moderately loose for iency and general deterioration of the weathercoating. . Fig. 10--(Bottom) Termination of insulation ea metal auface* above 300 F. the temperatures expected. When in stalling the pieces, full circumferential INSULATION SYMPOSIUM- 04 ' -HIGH TEMPERATURE THE OIL AND CAS JOURNAL joints are used between adjacent pieces of shop wcathercoatcd insulation, and . where practicable all longitudinal joints should be placed on, or as near as pos sible to the horizontal center line of the pipe. Where prime coated pieces of in sulation are installed the vertical joints should be staggered and horizontal joints made continuous. In all cases joints between adjacent pieces of in sulation must be tightly butted to gether. Wherever shop weathercoated insu lation is used, the pieces should be secured to the metal pipe surfaces with wire loops that have the ends twisted and embedded in the insulation, or steel bands. The type of sccuremcnt and the number used for each 36-in.long piece will depend on the diameter of the pipe. Packed openings . . . Openings larger than Va in. in all insulation should be packed with mineral wool. Normal joints between adjacent pieces of insu lation will be sufficiently tight to re quire no packing. After shop weathercoated insulation has progressed along the pipe suffi ciently not to interfere with mechan ics installing it, the longitudinal and circumferential joints between adja cent pieces of insulation should be weathercoated, so that no moisture can enter the insulation. Weathercoating is either applied by brushing, troweling or smearing on with a glove to a smooth finish. All exposed surfaces such as ends and edges should also be weathercoat ed. Prior to sealing circumferential joints they should be reinforced with a band of glass fabric at least 3 in. wide embedded in the weathercoating. Where beveled edge is used the glass fabric should be pressed into the joint; where straight edge is used the fabric should be relatively loose to permit some movement when the pipe ex pands. Where projections extend through the insulation, the joint should be sealed in the same manner as described for ves sels, etc. Where prime coated insulation is in stalled, the application procedure should be thd same as described for vessels, etc. Pipe Fittings, Valves Flanges In general, shop fabricated weather coated insulation covers should be in stalled on pipe fittings, valves, flanges, etc., from 3 to 24 in. in diameter. For diameters under 3 in. either standard pipe insulation or mineral wool as de scribed herein should be installed. It should be noted that whei) the diameter of the insulation used is greater than 16 in. the fittings, etc., are reinforced with glass fabric. Shop weathercoated pieces are optional for indoor applica tion. Whenever practicable, insulation for buttweld type elbows, tees, valves, etc., should be installed prior to the pipe insulation; butt weld caps and reduc ers are considered pari of the pipe in sulation. Where flanged or screwed type fittings and valves are to be insu lated such as flanged joints, elbows, tees, valves, couplings, etc., the pipe in sulation is installed first. When butt weld fitting insulation cannot be installed as mentioned, the locution of the extremities of the fit ting should be marked on the metal surface of the pipe, so that when fit ting insulation is installed it can be butted tightly against the pipe insula tion without cutting it. ' Parallel to pipe . . . AU fitting insulation should be installed with the center lines parallel and normal to the pipe insula tion of which they are a part. All joints in the fitting insulation, and where it comes in contact with pipe insulation should be butted tightly together. Where fitting insulation overlaps pipe insulation, such as in the case of flanged type, the space between the outside of the pipe insulation and the inside of the fitting insulation should be packed with scrap insulation or mineral wool. In many cases, because of the nesting arrangement of the insulation sizes, the need for packing is eliminated. . In places where it is possible to dam age fitting insulation after it has been installed or where additional rigidity is required because of external weights resting on the fitting, such as flange type, the void between the metal pipe fitting and the inside of the insulation should be reinforced with filler pieces made from scrap insulation. Places like these are the only ones where this should be done; all other voids are to remain unfilled. Openings larger than '/fe in. in all in sulation should be packed with mineral wool. A typical case is the space left after cutting valve insulation for bon net flanges of a globe valve. Shop weathercoated fitting Insulation should be secured to the metal pipe fitting with wire loops that have the ends twisted and embedded in the in sulation, or with steel bands. The type of securements and the number used will depend on the size and the num ber of pieces installed. Flanged fitting insulation should be secured where it overlaps the pipe insulation. Joints in fitting insulation should be weathercoated, reinforced and sealed as the work progresses against mois ture as described for shop weathercoat ed pipe insulation. In addition all ex posed ends, edges, etc., should be com pletely scaled with weathercoating. Furthermore, all joints between fitting insulation and pipe insulation should be reinforced with glass fabric. When fitting insulation is made in the field, either of shop weathercoated insulation or mineral wool the indi vidual pieces of insulation should be secured with wire loops, reinforced with a layer of glass fabric and finally given a finish coat of weatherproofing. Where it is necessary to insulate fit tings larger than 24 in. in diameter, prime coated curved pieces are used. The individual pieces should be either secured with wire loops or steel cables after which the insulation should be given a first spray coat of weatherproof ing into which is embedded a layer of glass fabric properly lapped and' fi nally a finish spray coat of weather proofing. . Insulation for steam tracing. . . In some cases, the outside metal surfaces of equipment, pipe and fittings are pro vided with tubing, through which steam flows for the purpose of furnishing ad ditional heat, or for stabilizing the chemical process, usually referred to as steam tracing. - In such cases, the insulation size used on equipment and piping, includes the steam tracer tube, so that when the insulation is installed it is placed against the tubing. When fittings are steam traced the size of the insulation is not increased to include the tubing, instead, at points of interference the insulation is gouged out to accommodate the steam -tracer tube. In order to reduce the amount of gouging the tubing should be located on the metal surface where the joint in fitting insulation will oc cur. The insulation procedure for a- stalling, packing, securing, reinforcing, and weathercoating is the same as de scribed herein. Where welding studs are used to secure insulation, care must be taken to avoid welding to the steam tracer tubing. ' ' Insulation for Turbines, Pumps ' Where hinged block can be used con veniently against irregular metal sur faces, they are' installed, packed, se cured, reinforced and weatherproofed as described herein. When hinged block cannot be used conveniently, plastic cements are ap plied to the irregular metal surfaces in lVi-in. thick layers, with each layer reinforced with 1-in. hexagonal galva nized poultry mesh, as used conven INSULATION SYMPOSIUM-- ---------------HIGH TEMPERATURE . tionally. However, after the hard coat added cost is more than offset by the several materials are specified. The - of plastic cement has been applied and fact that all parts of the installation are amount of handling of individual pieces 1 completely dry, the entire surface of not only properly insulated with the and the accompanying breakage also the insulation is given a first spray coat correct material, but when the work are decreased. Furthermore, handle- ' 'of weathercoating, into which is era is finished there will be no disagree ability of hydrous calcium silicate, par i - bedded a layer of glass fabric properly ments as to the amounts of insulation ticularly where small cutouts are need fla p p e d , and finished with a 1 /16-in. used for equipment, piping, fitting, etc., ed, simplifies application. thickness of weathercoating. between purchase and applicators. On An appreciably smaller number of Weathercoating should not be ap- many installations in the past this was field operations are required; in most plied by the spray method where over not so and necessitated the employ cases about half as many when other spray will require too much cleaning ment of,measuring teams. It is to be methods of application are considered. up; in such cases it should be applied noted that when the methods described The larger pieces of insulation now by either brushing, troweling or smear- are specified the applicator can quote made available through this procedure, mg on with a glove, to a smooth fin on the insulation work, without any nominally 18 by 36 in., reduces the ished surface, doubt as to the 'correctness of the number of joints to seal, pieces to han / It should also be recognized that by amount of material and the labor in dle and the amount of breakage, using the methods described herein volved; on the other hand, the pur * more engineering of insulation is re chaser knows what he is getting when Simplified operation . . . Either single or quired than Tieretofore. However, this the work is completed. shiplapped pieces are installed and se cured to the metal surfaces by the same Advantages of Method . . procedure; this greatly reduces and sim plifies the number of field operations when multiple layer insulation is ap A. Cost Benefits plied. Furthermore, the use of shipIn general, no heat need be provided lapped pieces has eliminated continu The writers have found the follow to dry out wet insulation. The elimi ous full depth joints between the out ing major cost factors to be noteworthy. nation of water-mixed plastic cements side of the insulation and the metal It is recognized that all factors are not makes it no longer necessary to employ surface to the vanishing point. It is of the-Same importance on ail installa costly heating equipment and waiting significant to note that continuous full tions and therefore no importance is - time, previously required to dry or thaw depth joints have been observed, even attached to the order in this list. out insulation. The only time such in some cases where multiple layers of Much less basic material need be equipment is needed is when the weath 4 or 6-in. wide pieces of insulation have requisitioned. Instead of about 10 per erproofing is not applied as outlined been used. cent excess for contingencies, only 1Vi herein or when plastic cement is used Individual mounting of the pieces to 3 per cent need be requisitioned, de for irregular surfaces. makes it comparatively easy to support pending on quantities and types of ma- the insulation at places where large lerials involved. Corrosion minimized . . . Because these openings occur in the metal surfaces 3-C methods produce weather protected in and where small and large pieces of Auxiliary materials, such as struc sulation of a high degree of moisture equipment are fastened to the metal tural steel shelf angles, channels, plates, resistance, and because practically no surfaces such as metal reinforcing pads, etc., welded to hot metal surfaces sole water-mixed materials are used, corro manholes, nozzles, etc. Furthermore, ly for supporting and attaching of in sion will be minimized on all metal sur-, all metal rings used for fastening insu sulation are entirely eliminated when faces covered. Furthermore, hydrous lation cables and bands at these points split pin or solid type welding studs are calcium silicate is alkaline and there have been eliminated. utilized. Small pieces of steel attached fore rust inhibitive. The use of hinged block which are at specified locations on equipment, Insulation work may be started wher normally 4.5 sq. ft., simplified install etc., arc costly and at present critical. ever convenient; however, it is best and ing the insulation on double curved In general costly materials needed to more economical to start installing in metal surfaces by eliminating the usual protect insulation against weather dur sulation at the topmost surface and 4 or 6-in. wide field scored blocks ing erection are practically eliminated, progressively weatherproof downward equivalent to 1.0 or 1.5 sq. ft. respec and only comfort of workers need be so that rain, even though unexpected, tively, and through the elimination of considered. It is to be noted that with will not wet the insulation and run be successively applied water bearing plas the methods described, insulation can hind it, and further accelerate corrosion tic cements. be applied in subzero climates with lit of the metal surfaces. It should be tle danger of freezing; in the past this noted that wetting the insulation is also Waste reduced . . . Running the cylin was a very costly item to control. of concern to the extent that moisture drical, longitudinal or vertical insula must be removed before the insulation tion beyond the junction of double Rai: resisting . . . The material, Kdrous is completely weatherproofed, to avoid curved surfaces, firmly supports the in calcium silicate, resists rain. If applied building up vapor pressure and decreas sulation on the double curve and sim insulation becomes saturated before ing thermal efficiency of the insulation plifies installing it whenever short radii weathercoating, or before application, until it becomes drv. occur. The use of filler blocks made it is not damaged except by freezing: from scrap insulation, which is always drying before coating is ail that is re Errors reduced . . . Because only one available, not only provides the neces &- , quired, but this is essential to prevent kind of basic insulation material of a sary support where needed but helps trapping moisture in the insulation. It single thickness is used for the full to dispose of waste insulation material f ' is to minimize the danger of this oc range of temperatures up to 1,200 F., and reduce the amount of cleaning up i- curring that the insulation is prime it will be found that errors in applying when the work is completed. coated in the shop. Insulation satu the improper insulation is greatly re Reinforcing the outside surface of rated after application does not fall off. duced, compared with projects of which the insulation with glass fabric simpli- INSULATION SYMPOSIUM-- \ ---------------HIGH TEMPERATURE THE Oil. AND GAS J O U R N A L _ v .> fr* fies the application while at the same time providing an inert material not subjected to deterioration from corro sion or other deleterious effects. It is essential that material conforming to the specifications set forth herein be employed, since the use of inferior ma terial will not produce a satisfactory job. Installing an extra layer of glass fab ric and a metal rain drip at and along the juncture of head and cylindrical in sulation on vertical vessels will prevent potential cracking of the weatherproof ing at this point, and make it possible to stop water from getting behind the in sulation. Furthermore, rain water as it runs down the head is diverted from against the sides of the insulation by the rain drip. Better fit . . . Furnishing curved seg ments of insulation of different radii for double curved surfaces will allow the insulation to fit better against these surfaces and appreciably decrease the amount of cutting and cracking of the insulation during application. On metal surfaces, such as are found in rectangular and square bin and duct construction it will be seen that the use of welding studs greatly simplifies se curing the insulation at corners, stiffen ers, etc. With individual mounting, any part or piece of insulation can be removed without disturbing the remaining insu lation or have it fall off, when it is necessary to make changes to the metal surfaces insulated or to repair the in sulation. Removed material when han dled with moderate care can be re used. Each piece of insulation is individ ually mounted and the relative change in dimensions due to longitudinal and radial thermal expansion of the metal surface and the shrinkage of the insu lation need be compensated for at the joints only of the small units, usually 4 Vi sq. ft. Operations reduced . . . The strength of the insulation material and the inde pendent support method described for installing, and removing insulation at weld lanes has simplified the applica tion at these places by reducing the number of field operations, and has eliminated the double continuous steel plate border strips, previously tack welded along both sides of the seam. These plates were used to fasten the cables or bands of the permanent in sulation and provide a lane for remov able insulation over the weld seam. The use of welding studs for secur ing insulation to metal surfaces has eliminated all sagging, when insulation is installed in overhead positions or any other position where the dead weight of the insulation rests on the attachment, such as cables, bands, etc. The subsequent attachment of cables, bands, etc., for securing insulation is eliminated in the case of vessels, equip ment, etc., except when alternate meth od of application is used. Little Job cleaning. . . The strength of the material is such that workmen can walk on it without damaging any ma terials. While not recommended in gen eral, in cases where necessary, scaffold planks can be placed on the finished insulation without damage. Further more, few repairs are needed at the end of the job because both the insulation and the coating resist moderate abuse. Little expense in job cleanup is in volved. A job involving about $100,000 worth of insulation has only enough waste material accumulated to be car ried awuy in a pickup truck. After completion of the job, since practically all items are listed on a ma terials order, measuring teams are not needed for quantity surveys, with sub sequent negotiations because of dis agreements. In case of fire the mounting of in dividual pieces prevents the falling off of the insulation as occurs when cables or bands are used. B. Personnel Considerations From the standpoint of the work men, the following factors should be considered. 1. It is felt that as the installed cost of thermal insulation decreases, the amount of insulation to be applied will be increased. 2. Hydrous calcium silicate is pleas ant to handle, and permits a better ap pearing job for the conscientious crafts man. 3. There is inherently less dust than with other softer materials and the basic material is not a hazard. 4. Since the amount of gymnastic work around fittings to be applied from high scaffolds is reduced, so is the ac cident hazard reduced, 5. Due to hydrous calcium silicate being insoluble in water, it does not produce a slimy surface on planking after rain when partially redned, and thereby reduces the accident hazard. C. Maintenance A major problem in thermal insula tion in the past has been maintenance which is always necessary because of job accidents which result in damage to either the weathercoating or the insulation or both. It seems obvious that repairs to the coating or the insu lation have been simplified with pro cedures described. When damage occurs to the weather coating, it is repaired by brushing on weathercoating or brushing on weath ercoating reinforced with glass fabric depending upon the extent of damage. When damage occurs to the insu lation, if is removed and new insula tion installed. It should be noted that where the welding stud method of at tachment is used, only those pieces damaged need be removed and replaced without disturbing remaining material. If already weathercoated, the coating is cut along joints, and the replacement made and recoating applied, using glass fabric reinforcing where desirable. This partial removal also applies to parts of fittings which are damaged. In service, U`is anticipated that for high temperatures there may be some distress in joints, even though rein forced, after some tim of service. If so, maintenance crews can recoat the . checked areas easily' by brushing on ad ditional coating and reinforcing. It is felt that recurrence after such treat ment will occur rarely especially where the bevel type joint is used. Here is an item on which improve ment can be expected when more elas tic and durable coatings become avail able. It is to be noted that conven tional coatings used in the past always were a source of a great amount of maintenance due to checking and cracking. ,, In service, it is also to be noted that due to the toughness of the weather coating and strength of the insulation material, equipment and piping cov ered with insulation can readily be used to support scaffold planks with mod erate dead loads, without damage. Specifications, Equipment, and Storage. . No equipment is required for this method that is not already on the mar ket. The fo llo w in g e q u ip m e n t is u sed in addition to the usual tools of the trade of insulation applicators: 1. Welding generators, 400 amp., for every two weld guns. ; - 2. Weld gun of the timed-volt-am- pere type, equipped with proper chuck and ferrule holder. ' "> ' - 3. S p ray equipment with necessary compressed air and accessories. , 4. Hand electric drill for extra holes for weld-pins. Canvas or rubber gloves for wiping on coating, v .? ' As mentioned, code requirements or INSULATION SYMPOSIUM-- --------------------------- -- -------- -...- -- -H IG H TEMPERATURE f '," T^Jesign considerations sometimes pro of fittings have been specified. 'This . hibit any field welding of even light more positive estimate of quantities is metal, such as welding studs on equip possible because it is known where ment. In these cases, the present con each type of insulation begins and ends, ventional methods of supporting insu which had not been true in the past , iation with steel clips, etc., must be pro- when builtup fittings overlapped pipe `f' vided, and the inflation secured with insulation. >. . jcafeles, bands, or wire. Also, provision Therefore, it is no longer necessary * must be made for expansion joints. to purchase excess material in large However, from this point on, packing, quantities to make certain there is suf reinforcing and weatherproofing pro ficient quantity at the job site for com cedures described can be followed. The pletion. For the application procedure galvanized beet metal strip at expan described, no material is ordered in sion joints can be installed as noted excess of iV4 to 3 per cent above the w below. take-off quantities. On foreign proj When the use of welding studs is ects, these excess quantities are in not prohibited, and it is desired to use creased slightly. cables or bands, the steel supports can still be eliminated by using welding Specifications, , , Under this system, the studs on only the bottom row of insu designing engineers indicate sizes and lating blocks, where the insulation lengths of all units, and the thickness starts, and immediately above the of insulation required. Since the de planned expansion joint. Since this row marcation between single and ship- of blocks is fixed, and the material has lapped layers is 700 F., expected op sufficient strength to carry the insula erating temperatures are indicated tion above it to the next expansion joint, merely as above or below this tem shelf angles are not required. The in perature. By limiting the specification tervening insulation can then be at to such simple notation, the designing tached by cables or bands. engineers have not placed in the hands Again, a sufficiently strong material of the manufacturer of insulation val permits the construction of a simple uable data on expected operating tem expansion joint by nailing a 6 to 8-in. cpoenraftiduerenstiawl.hich they may wish to keep wide strip of galvanized sheet metal to From the writers' experience, this the insulation immediately above and system involves some added engineer . over the joint. The glass fabric for the ing time. The insulation manufacturer section above the joint is started flush determines quantities required to insu with the lower edge of the sheet metal late irregular shapes since these quanti and carried upward without restraining ties can best be determined by the man the possible motion in the joint. It ufacturer, who adjusts quantities to the should be noted that the glass fabric dimensions of the pieces of insulation and weathercoating is carried up to the he makes. - top of the insulation just below the joint before attaching the metal strip. Simplifications . . . In order to simplify - This permits vertical motion of the taking off and summarizing insulation metal strip without exposing any in materials for requisitioning, standard - sulation to weather. sketches and tables have been devel If staggered block construction is oped for use with equipment draw used, the blocks are installed beyond ings, insulation design specifications the planned expansion joint, and each and to-scale single line isometric draw block above the joint attached with ings. The procedure serves as a quick welding studs. Then the alternate means for determining the shape, se- blocks which span the joint are sawed curement, reinforcement, weathercoat completely through and the metal strip ing, and joint requirements for any attached as mentioned. given piece of equipment and pipe size Requisitioning Insulation Materials for any temperature and insulation thickness. With this system of insulating a Identification marks for the various more caref ully organized material take insulation shapes are also obtained, par off is required. However, with the tially by codes. It should be noted that proper factors and tables the amount this procedure in quantity survey gives of each material can be arrived at read the quantities of piping and fittings at ily with little more effort than here the same time that it gives quantities tofore. of insulation. Final quantities to be It should be noted that there is no ordered are obtained by multiplying doubt as to the exact quantities of each the square feet of areas or the lineal material needed when the take-off is feet of piping by factors. It is empha completed, because the surface areas, sized that this includes the quantities length of pipe insulation and number of auxiliary materials as well. .Identification System for Insulation Material Because all materials are "tailor made" pieces, and each piece has a definite place in the over-all erection scheme, the manufacturer marks each piece and the carton in which it is Shipped to identify its use. When items are interchangeable for dimensions on several pieces of equipment, for exam ple, all interchangeable identifications are used. Sample of marking: "A tower 80 ft. high on the shell and 10 ft. in diameter with 2-in. thick insulation, having ellipsoidal heads, des ignated E-101, would have each shell insulation piece marked 120 x 2, with the cartons marked 36 sq. ft., 120 x 2 E-101, and each piece of head insula tion marked, Hinged Block 2, with cartons marked 36 sq. ft. Hinged Block 2 E-101. For five 6-in. butt-weld elbow insulation, 2 in. thick, shop-coated with weathercoating, each piece would be marked 6 x 2 BWL and cartons marked 5 Butt weld Ell Coated 6 x 2." Detailing special insulation . . . Because it is impractical at this time to stand ardize all insulating materials including special shapes or dimensions, it becomes necessary to detail either new pieces of insulation for shop fabrication or to use combinations of standard pieces. The decision must be made on the econom ics of shop or field fabrication, taking into account the cost of possible added engineering, manufacturing and ship ping difficulties and handleability in the field. When the decision is in favor of field manufacture, the proper pieces must be requested for easy assembly, and instruction for erection forwarded to the field. Storage Arrangement The storing or warehousing of any kind of material on any size project is always a problem, with its major dif ficulty the easy withdrawal of specific items. To avoid rehandling of mate rials in finding specific items, or due to errors in selection, the markings de scribed permit predetermined locations in the storage area to be used immedi ately upon removal of shipments from railroad car or truck. More care in locating items upon re ceipt at the warehouse has been found to save an appreciable time when with drawals are made. However, the keep ing of records of receipts and withdrawings accompanying the actual mov ing of the materials, enables an accu rate running record to be kept available at all times. This is particularly de sirable when-partial shipments front the manufacturer are being handled. INSULATION SYMPOSIUM- :t 98 J -------------- HIGH TEMPERATURE THE OIL AND GAS JOURNAL