PANEL DISCUSSION MODERN MATERIALS TECHNOLOGY IN OIL STORAGE, PROCESSING AND HANDLING (INCLUDING HIGH AND LOW TEMPERATURES) Chairman: H. G. GEERLINGS (Netherlands) Vice-chairman: J. GORDON PARR (Canada) Prof. Dr. H. G. GEERLINGS welcomed the delegates. Dr. GEERLINGS had agreed to take the chair at this meeting owing to the absence of Prof. Dr. Ir J. C. VLUGTER who regretfully was unable to be present because of personal reasons. Unfortunately, for various reasons, several authors could not attend. The paper by Professor VERBRAAK, was presented by Dr. GEERLINGS and that of Messrs. LAN- CASTER and HOYT by Mr. ZEIS. Because the subject matter covered such a wide field, the Chairman decided to divide discussion into three areas. The first three papers relate primarily to the application of the stronger steels to the con- struction of oil storage tanks and similar types of construction. This section was chaired by Prof. Dr. J. G. PARR of the University of Windsor, Canada. It was considered that as low stress fracture is an im- portant aspect in the testing and operation of tankage, these papers would provide a convenient introduction to a second group of five papers, the subjects of which relate to weldability, brittle fracture and other materi- als problems, and to the standardization of specifica- tions. Into a third section were grouped those papers on the newer materials which are being gradually introduced into the petroleum industry. The discussion which followed the papers is summarized briefly as follows : Tankage and similar construction Chairman, Prof. J! G. Parr Much of the discussion on the first three papers related to brittle fracture characteristics and the sig- nificance of test methods. Mr. M. J. NOONE (Whessoe Ltd., U.K.) asked Mr. LANGEVELD why a 40 ft-lb Charpy V-notch had been selected as a criterion for the steel and the Charpy keyhole test for the welds. In reply, Mr. LANGEVELD and Dr. GEERLINGS indicated that while there is a necessarily arbitrary nature to any decision of this sort, their decisions were based upon their particular experience. They also referred to tests carried out by Pellini years ago indi- cating that for high strength steels a higher value should besetthanformildsteels, andto requirements of Lloyds. Specific experience was quoted to show that Charpy keyhole 15 ft-lb levels did not always correlate with satisfactory performance, and operational failvres have arisen. On this basis, the Charpy V-notch test is to be preferred. Several of those present emphasized the importance of the thickness effect. The panel generally agreed with Mr. NOONE about the dangers of extrapolating thin plate data to thick plate, and the difficulties of relating any laboratory test to field performance. A question about vanadium and niobium additions elicited the reply that higher yield strengths could be attained while preserving the notch toughness if the rolling practice and finishing temperature are very carefully con
SYNTHESIS OF CYCLOHEXANONE BY LIQUID-PHASE OXIDATION OF CYCLOHEXANE, PHENYLCYCLOHEXANE, AND CYCLOHEXANE CARBOXYLIC ACID Abstract The efficiency of the technical preparation of cyclo- hexanone by liquid-phase oxidation of cyclohexane is limited owing to the fact that, to effect a sufficiently rapid oxidation, the process has to be carried out at temperatures at which the hydroperoxide formed as an intermediate product decomposes in a non-directed way, and the resulting products (mainly cyclohexanol and cyclohexanone) are further oxidized. A survey is given of the reactions involved. Subsequently, three methods devised to avoid con- ditions detracting from the process efficiency, are dis- cussed, viz. : 1. Oxidation of phenylcyclohexane, i.e. introduction of the activating phenyl group; the oxidation can then be carried out under conditions preventing decom- position of the hydroperoxide, and this hydroperoxide can be decomposed in the absence of oxygen to form phenol and cyclohexanone. 2. Oxidation of cyclohexanecarboxylic acid by means of steam and air, the cyclohexanone formed in this process being removed from the oxidation zone immediately after its formation, so that further oxida- tion is prevented. 3. Oxidation of cyclohexane in the presence of boric acid, so that the decomposition of hydroperoxide, though taking place during the oxidation, is directed to the formation of cyclohexyl borates, which are less liable to further oxidation than the mixture of cyclo- hexanol and cyclohexanone obtained in the absence of boric acid. Résumé Dans la préparation technique de cyclohexanone par l'oxydation dans la phase liquide de cyclohexane, le rendement est limité par suite du fait que, pour obtenir une oxydation suffisamment rapide, il faut opérer á des températures auxquelles l'hydroperoxyde formé intermediairement se décompose sans direction déter- minée et que les produits formés (essentiellement du cyclo-hexanol et du cyclohexanone) sont oxydés plus loin. On donne un aperçu des réactions qui se produisent. Ensuite on traite trois méthodes selon lesquelles on a essayé d'éviter ces circonstances limitant le rendement. Les voici: 1. L`oxydation de phénylcyclohexane dans laquelle, par l'introduction du groupe de phényl activant, l'oxydation peut être effectuée dans des circonstances où I'hydroperoxyde ne se décompose pas, après quoi l'hydroperoxyde peut, en l'absence d'oxygène, être décomposé en phénol et en cyclohexanone. 2. L'oxydation d'acide cyclohexane-carboxylique á l'aide de vapeur et d'air, dans laquelle le cyclohexanone formé est, immédiatement après sa formation, enlevé de la zone de réaction de sorte qu'il ne peut être oxydé plus loin. 3. L'oxydation de cyclohexane en présence d'acide borique de sorte que la décomposition de l'hydro- peroxyde se produit pendant l`oxydation, il est vrai, mais qu'elle est tout de même dir
EXPLORATION IN THE GULF OF MEXICO Abstract The Gulf of Mexico occupies a large sedimentary basin 1,000 miles by 600 miles with 375,000 square miles having a water depth less than 1,000 fathoms. Tertiary and Mesozoic Sediments including salt are known to be present. Explorationin the Gulf of Mexico started in 1938 as a logical extension of operations on land. By 1966,4,300 crew months of seismic work had been completed and 7,500 wells had been drilled, resulting in proved reserves of approximately 2.2 billion barrels of oil and 20.7 tril- lion cubic feet of gas. Industry had approximately 58 mobile drilling rigs, 24 seismic crews and 900 geologists and geophysicists engaged in exploring the Gulf for oil and gas. Offshore exploration depends primarily on geophy- sics of which seismic is the most important. Recent and continuing improvements in technology give reason to expect that the effectiveness of these methods will be much better in the future. Drilling equipment and techniques are keeping pace, providing the capability to produce any prospect having adequate potential. Modern developments in geology, geophysics and drilling will enable the explorationist to locate major hydrocarbon deposits wherever they may exist in the Gulf of Mexico. Résumé Le Golfe du Mexique occupe un grand bassin sedi- mentaire, long de 1 .O00 miles et large de 600 miles, dont les 375.000 miles carrés ont une profondeur d'eau de moins de 1.000 brasses (500 mètres). L'exploration du Golfe du Mexique a commencée en 1938 comme évolution naturelle des activités sur terre. Jusqu'en 1966 on avait achevé 4.300 mois-équipes d'ex- ploration par sismique et 7.500 puits, à base de quoi on avait établi l'existence définitive de 2,2 trillions de barrils (billions américains) de pétrole et 20,7 quin- tillions de pieds cubes (trillions américains) de gaz. I1 y avait en 1966 environ 58 appareils de forage mobiles, 24 équipes sismiques et 900 géologues occupés dans l'exploration du pétrole et du gaz dans le golfe. L'exploration pétrolière au large dépend pour la plu- part de la géologie et surtout de la sismique. Vu le progrès récemment acquis et toujours en train on peut croire à des améliorations progressives pour l'avenir. Les techniques et les moyens de forage marchent de pair avec ceux de la géophysique, qui doit nous assurer de développer toute accumulation rentable. Avec la marche en avant dans la géologie, dans la géophysique et dans le forage les explorateurs pétroliers pourraient trouver tous les depôts qui peuvent exister dans le Golfe du Mexique. Even though the oceans and the Sediments beneath the oceans are making substantial contributions to the ever-expanding needs of man, it is generally recognized that we have only begun to develop the potential of these marine areas. Consequently, oceanographic studies and exploration of the ocean floors have been expanded tremendously in the past four years. Thus, a review of exploration
PANEL DISCUSSION DEVELOPMENTS IN THE PRODUCTION AND USE OF LUBRICANTS (INCLUDING MARINE DIESEL ENGINES) Chairman: R. M. JUBLOT (France) Vice-chairmen : J. ROMNEY (Great Britain) V. BISKE (Great Britain) For both presentation and discussion, the eight papers were divided into four groups. Initial general comments on each group were made by the Chairman, while more detailed reviews and questions were pre- sented by Mr. BISKE for group 1, the papers dealing with refining and production, and Mr. ROMNEY for groups 2,3 and 4. Developments in production of lubricants Mr. ROMNEY queried whether the actual lubri- cating properties of oils were being disregarded in view of the importance of other functions which modern oils had to fulfil. The author had indicated the need for very high VI oils and Mr. ROMNEY wondered whether, since VI improvers tended to interfere with the functioning of other additives, there were prospects of non-derating negligible shearing VI improvers. Further, would it be correct to say that refining methods, before the introduction of hydrogenation processes, were capable of making good oils from any crudes, if sufficient were spent? The Author replied that lubrication properties were certainly being watched, that progress in VI improvers was undoubtedly on the way, and that the modern hydrogenation processes made possible the production of oils which could be economically raised to appro- priate performance levels with additives in the normal way. However, should unusually high VI levels be sought in the future, this would probably lead to selection of special crudes, even for feed to the hydro- genation units, thus bringing us back to economic and additive interaction problems. As to the capabilities of the pre-hydrogenation processes, he felt that unless the desired final product were present in the crude, such processes could not produce good lubricants however much were spent. Mr. BISKE confirmed Mr. PETRY'S comment that acid refining was still viable, and was in fact legally called for in some cases. IV-23 In answer to other questions from the panel, Mr. PETRY stated that the avoidance of excessive exhaust valve burning, especially in Diesel engines, would need close control of the use of metal containing additives; with regard to future high quality transmission oils, it was hoped that this level would be obtainable through new developments of mineral oils, and that the use of Synthetics could be avoided in most cases. If this turned out not to be feasible, and if Synthetics were the only technical answer to future requirements, car builders would have to accept the fact, and the cost. As regards the trend towards paraffinic oils for lubri- cation of marine engines, there was strong pressure in that direction from the petroleum industry, but it was also true that there was opposition from many engine builders, and it was to be expected that the acceptance of this change might yet require some time. In reply to
PRODUCTION OF LOWER FATTY ACIDS BY THE LIQUID PHASE AIR OXIDATION OF PETROLEUM NAPHTHA ; ESPECIALLY NAPHTHENIC NAPHTHA Abstract For the purpose of producing lower fatty acids such as formic, acetic, propionic and succinic acid, liquid phase air oxidation of light naphtha, especially naphthenic, was investigated. From basic research, new information about the Co-oxidation effect and the effect of catalysts, etc., were derived and under the optimum reaction condition formic, acetic, propionic and succinic acid were obtained in the yield of 5-45, 50-70, 3-12 and 2-5 wt. In the small scale pilot plant test, many important techniques were developed such as the method of continuing the reaction safely and a unique process for removing water from the oxidate mixture, etc. respectively. Résumé L`étude a pour objet un procédé de fabrication d'acides gras inférieurs, acide formique, acétique, pro- pionique et succinique par oxydation par l'air en phase liquide des naphta légers particulièrement des naphta de pétroles naphténiques. Des recherches fondamentales ont fourni des connaissances nouvelles sur l'effet de la Co-oxydation ou l'effet des catalyseurs, etc. . . . , et dans les con- ditions optima de réaction, les acides formique, acétique, propionique et succinique sont obtenus avec des pourcentages en poids respectivement égaux à 545, 50-70, 3-12 et 2-5. Au cours des essais sur une unité pilote à petite échelle, diverses techniques importantes ont été mises au point, notamment une méthode pour la poursuite de la réaction en toute sécurité, et un nouveau procédé pour extraire l'eau du mélange oxydé.
For preparing lower fatty acids by the oxidation of petroleum naphtha, some processes using butane', n-paraffins2 and isoparaffinic light naphthas3 as raw materials have been presented. Already in 1958 the authors started the basic research of the liquid phase air oxidation of saturated hydrocarbons, especially naphthenic hydrocarbons which had not been recom- mended as raw materials. As the result of this investigation, following facts have been found out; that is, by adapting adequate reaction conditions as well as the choice of catalyst, lower fatty acids can be obtained from naphthenic hydrocarbons in high yield and the ratio of (acetic acid)/(formic acid) can be varied in a wide range according to the requirement. On the other hand a small scale pilot plant test was carried out and completed successfully in 1965. Following are the outlines of the result of those studies. by NOBUTO OHTA, Chief of 4th Division, Govern- ment Industrial Chemical Research Institute, Tokyo, and TAKE0 NAKAMURA, Director of Central Research Institute, Tekkosha Co., Ltd., Japan. OXIDIZABILITY OF NAPHTHENIC HYDROCARBONS AND PRODUCIBILITY OF LOWER FATTY ACIDS The oxidation of pure naphthenic hydrocarbons In the liquid phase oxidation of naphthenic hydro- carbons, the reaction rate and the composition of produc
USE OF PETROLEUM DERIVATIVES IN THE BUILDING INDUSTRY i Abstract The petrochemical industry provides plastics and rubbers, which are used in increasing quantities in the building industry for non-structural as well as for structural applications. They play an important part in the development of the industrialization of the building industry. Uses of plastics and rubbers are already being made at building sites, in services (plastic plumbing, etc.), finishing, protective and decorative coatings, insulation (foamplastics), interior and exterior panels, etc. Research on structural applications leading to "plastic houses", with or without conventional frames, roof constructions, etc., is in full development.
The petrochemical industry produces a large variety of chemicals and polymeric products, using oil fractions or natural gas as primary materials. Many industrial solvents and by far the greater part of the group of high molecular synthetics, comprising plastics, rubbers, resins and synthetic fibres are produced by the petrochemical industry and can therefore be considered as petroleum derivatives. Exceptions are, of course, synthetic products derived from coal, while an important polymer such as polyvinylchloride contains a large amount of chlorine, which is produced from rock salt. When discussing the use of petroleum derivatives in the building industry, plastics and related products should be given first attention, as these products are being applied in rapidly increasing quantities. As is well known, the plastics industry throughout the world shows a growth rate surpassing that of all other industries. It is useful to compare world production and growth rates of plastics with those of a number of important materials, as is done in Fig. 1. This figure shows that for the present the production of plastics and synthetic rubbers, expressed in tons per annum, is only a minor fraction of that of oil and gas or the most by PROF. DR. Ir. A. J. WILDSCHUT, Technological University, Delft, Holland, Department of Civil Engineering, section Building Materials. , Rsum L'industrie ptrochimique fournit les matires plastiques et les caoutchoucs qui sont utiliss en quantits croissantes dans l'industrie de la construction de btiments pour les applications non structurales aussi bien que structurales. Ces matriaux jouent un rle important quant au dveloppement de l'ndustrialisation dans le btiment. Les matires plastiques et les caoutchoucs sont dj utiliss dans les chantiers de construction, les installations (plombage plastique etc.), les revtements de finissage, de protection et dcoratifs, l'isolement (mousses de plastique), les panneaux d'intrieur et d'extrieur, etc. Les travaux de recherche se poursuivent activement sur les applications structurales. important building materials. However, if we assume that the growth rates of oil and gas on the one side and of plastics and rubbers on the other continue unchanged ti
PANEL DISCUSSION NEW OIL PRODUCING REGIONS CHAIRMAN: F. NAFICY (Iran) VICE-CHAIRMEN : A PERRODON (France) H. KÜPPER (Austria) Chairman's introduction Mr. NAFICY: It is indeed a great honour for me to be selected by the Scientific Programme Committee and by the Permanent Council of the World Petroleum Congress to preside over a meeting which brings to- gether some of the most distinguished personalities of the Exploration side of the Petroleum Industry. It is further a great honour for me that so many of the personalities have responded to my appeal and have accepted to present papers, which I am confident will remain as works of reference for many years to come. In the growing need for petroleum, whether liquid or gas, and its products, the search for petroleum extends farther and farther not only into the different parts of the world, both on land and offshore, but also into the deeper parts of the stratigraphic column and the earth's crust. Realization that there seems to be no hard and fast rule to the occurrence of petroleum as to the rock type, age, depth, environment or setting, except for a few basic prerequisites, coupled with advances in the field of technology, perfection and development of finer tools as well as progress in analy- sis and rationalization of the basic factors governing such subjects as migration, accumulation, recovery and so on, gradually resulted in new discoveries and development of new, and revival of old, oil producing regions. It would even seem that the sky or the so- called basement are no limits, since some statements have already appeared in print concerning whether there might be petroleum on some heavenly bodies or in the basement. It is, therefore, natural that a panel discussion such as this one has an immense task of not only high- lighting and authoritatively examining the widely separated territories of the world, but also in some instances of continents that would qualify under the title of this panel discussion within the prescribed time limits. It is hoped that such a goal will be achieved. From the Cook Inlet Basin, Alaska, where oil and gas fields produce from the tertiary sandstones and conglomerates of continental origin, to the vast pro- vinces of Siberia, where oil and gas accumulations have been found in Mesozoic and Paleozoic. From the North Sea where active exploration is still continuing at a fast pace and where gas accumulations have al- ready been discovered, through the Groningen gas- field in Netherlands, which established itself as a major find, and the Ayoluengo oil-field in Spain to Libya- Algerian Sahara and Niger Delta on the West Coast of Africa, rocks of different ages have been found to be 290 New Oil Producing Regions petroleum-bearing, establishing new oil-producing regions. Australia has also come a long way since a decade ago with oil and gas discoveries ranging from Ordo- vician to Tertiary. Further discoveries were also made in the Persian Gulf and th
INDUSTRIAL PROCESSES FOR THE CATALYTIC VAPOR-PHASE OXIDATION OF HIGHER ALKYLATED AND CONDENSED AROMATICS TO FORM POLYCARBOXYLIC ACIDS AND THEIR ANHYDRIDES Abstract oxidation processes : The paper reviews the following vapor-phase (I) Production of phthalic anhydride from naphtha- (2) Production of maleic anhydride and fumaric acid (3) Production of pyromellitic dianhydride from (4) Production of naphthalic anhydride from acena- Modern industrial processes are briefly described. The economic aspects, raw materials to be used and the future development of raw materials to be used for the above mentioned processes are critically reviewed. The by-products, their economic utilization and their removal in post-installed purification units are dis- cussed. Finally, a forecast of future development is made. lene and orthoxylene; from benzene; durene and 1, 2,4, 5-alkyl benzenes; phthene. Résumé phase gazeuse: L`auteur étudie les procédés suivants d`oxydation en (I) Fabrication d'anhydride phtalique à partir de naphtaline et d'orthoxylène; (2) Fabrication d'anhydride maléique et d'acide fumarique à partir de benzène; (3) Fabrication d'anhydride pyromellitique à partir de durène et de benzènes d'alcoyles 1,2,4, 5; (4) Fabrication d'anhydride naphthalique à partir acénaphtène. Après une description succincte des procédés de fabrication industrielle, l'auteur donne un aperçu critique sur leur rentabilité, les matières premières utilisées et l'évolution future de ces dernières. En outre, il traite des sous-produits obtenus, de leur élimination dans des unités d`épuration ultérieures. En conclusion, l'auteur donne un pronostic pour l'avenir.
In the last twenty years or so carboxylic acids with two and more carboxylic groups, particularly their anhydrides, have become extremely important for the production of plasticizers, synthetic resins, polyesters, synthetic lubricants, insecticides and many other products. In 1966, for example, the production of phthalic anhydride will reach I million tons a year or even exceed this figure. In addition to acetic acid and its anhydride (approx. 1.6 MM tons per year) and tere- phthalic acid and its methyl ester (approx. 750 M tons per year) phthalic anhydride is, thus, the most im- portant synthetic organic acid for the chemical industry and the yearly rate of increase is estimated at 7 per cent at least. Another important dicarboxylic acid which is like- wise obtained as anhydride on an industrial scale is maleic acid with a world production estimated at 150,000 tons in 1966. These two dicarboxylic acids are manufactured in almost all industrial countries. There by G. W. IBING, RUHROL. Bottrop, West Germany. are probably 100 phthalic anhydride plants and 45 maleic anhydride plants in operation. The subject matter of this paper is polycarboxylic acids and their anhydrides which can be manufactured by economic processes t
STRESSES IN TUBULAR GOODS IN PRODUCING WELLS Abstract Résumé In the assessment of the strength of tubulars special En vue d'estimer la résistance des tubes, les effets des attention is given to the effect of hydrostatic stress. contraintes hydrostatiques sont étudiés. Certains Several phenomena are shown not to be affected by the phenomènes dépendent des conditions hydrostatiques, hydrostatic condition while others are. A distinction is d'autres en sont indépendants. Ceci conduit à la made, therefore, between absolute quantities and distinction entre les valeurs absolues et les valeurs "effective" quantities, i.e. the departure from the hydro- "effectives" qui ne correspondent pas aux conditions static condition. hydrostatiques. The first part of the paper gives a method for deter- La première partie de l'article est la description d'une mining axial forces resulting from changes in tempera- méthode de détermination des forces axiales engen- ture and pressure, internal or external. The method is drées par les changements de température et des applicable to both casing and tubing strings, uniform pressions internes ou externes. Cette méthode s'app- or composite. Buckling as well as various completion lique aussi bien au train de tige qu'au tube de cuvelage, and landing methods are considered. The forces being qu'ils soient homogènes ou composités. Le flambage, known, the stresses can be determined, les differentes méthodes de complétion et de scellement I n the second part of the paper strength is assessed sont considerées. La connaissance des forces permet under combined loading by axial force and internal or de déterminer les contraintes. external pressure. The method is based on the Huber- Dans la seconde partie de l'article, une étude est Hencky-von Mises yield criterion. Account is also faite sur la résistance à l'action de la contrainte axiale taken of the consideration that, under simple loading et des pressions internes ou externes. La méthode est conditions, discrepancies between API strength data basée sur le critère de limite de fluage de Hubrr- and theoretical values for ideal tubes result from imper- Hencky-von Mises, en tenant compte de fait que dans fections affecting the tangential and radial effective le cas d'une surcharge simple, la différence entre les stress, while both axial and hydrostatic stress remain valeurs de la résistance API et les valeurs théoriques uniformly distributed. Criteria are developed that, in pour le cas d'un tube idéal, sont la conséquence the case of simple loading, reduce to the API data. d'imperfections qui affectent les contraintes tangen- Results are in accord with the scanty experimental tielles et radiales, tandis que les contraintes axiales et data on combined loading, both in cases of yield hydrostatiques sont distribuées de se ramener aux collapse and elastic collapse. données API, dans le cas d'une surcharge simple. Ils sont en
BRITTLE FRACTURE OF HEAVY WALL VESSELS Abstract Résumé In this paper, data will be given of test procedures for high-strength and extra-high-strength steels especially for applications in high-pressure equipment. It will be argued in the paper that the specifications for impact tests in these applications should be based on the results of large-scale tests. Dans cet article des renseignements sont donnés sur les procédés d'essais relatifs aux aciers de haute et très haute résistance spécialement orientés vers la construc- tion d'appareils de haute pression. On a également attiré l'attention sur le fait que, en vue de telles applications, les spécifications pour les essais de résilience doivent être basés sur des essais utilisant des échantillons de grande dimension.
Not so many years ago the requirements for pressure vessels could still be met by the use of low strength steels. Fracture-safe design was mainly based on prac- tical experience and a few simple mechanical tests. A great number of service failures had been analysed and translated into improved methods of design and steel specifications. In the past two decades this procedure has certainly led to a gradual decrease of service failures after the first explosion of brittle fractures during the World War II period. At the moment that we have learned to walk in this field without too much stumb- ling we are told by industry, however, that walking is too slow and that we should drive a car. The develop- ment of new chemical processes asks for pressure vessels of ever increasing size and operating pressure. To meet these modern more severe requirements new high strength steels of the normalized or quenched and tempered type have to be used. There is, however, insufficient experience with the new high strength steels to formulate specifications, which will guarantee the same degree of safety as the old specifications for the conventional steels. In solving this problem we are hampered by the lack of knowledge on the micro and macro aspects of fracture initiation and propagation. There are nearly as many theories of fracture as there are actual service failures. Moreover, it seems to be a special hobby of scientific investigators in this field to devise their own tests for determining the ductile-brittle by Prof. Dr. Ir. C. A. VERBRAAK Metaalinstituut TNO and Technological University Twente í Holland) transition in steel. There is a rich choice of divergent test methods and no general accepted order of merit for these various tests. Still each day many engineers have to take the responsibility for the choice of a specific steel for the fabrication of a large variety of equipment. The national specifications might be either too severe or too vague according to the personal opinion of an individual engineer. One consideration, however, is predominant for him : there should be no failure in practice, because this could mean the end of his career as an