THE FATAL BOILER EXPLOSION AT EAST GREENWICH
THE ADJOURNED INQUEST – VERDICT
On Tuesday Mr. Coroner Oswald conducted his enquiry in reference to the deaths of William Wilson Shaw aged 45 of 26 Quarry Road, Wandsworth and James Peter Coombes, aged 45 of 8 River terrace, Blackwall Lane, east Greenwich, whom, as reported in the Kentish Mercury of December 21st were killed on the previous day as the result of a boiler explosion at the generating station of the South Metropolitan Electric Light and Power Company at Blackwall Point. Both Mr. Shaw who was an inspector in the employ of the National Boiler and General Insurance Company Limited of London and Manchester and Coombs who was a foreman fitter employed at the Electric Light Company were practically blown to pieces and considerable difficulty was experienced in the process of identification. At the time of the explosion Mr. Shaw, assisted by Coombes was endearing to locate a leak in the drum of the boiler – Mr. George Whale, solicitor of Woolwich, represented the Electric Company, Mr S. Row, solicitor, appeared for Mr. Shaw’s family and Mr. G. Michael Williams for the boiler company.
The Coroner said that since the enquiry was adjourned he had been informed that the Board of Trade were making an exhaustive enquiry into the cause of the explosion and trying to find out all they could. So far as he was concerned it was his duty to establish a prima facie case to enable the jury to return an intelligent verdict. In the jury being sworn the Coroner called attention to the absence through illness of one of their number (Mr Percy Rolls who was chosen foreman on the former occasion) and to that of another who he pointed out was liable to called upon to pay £20 the amount of his recognisance’s. The latter however attended before the taking of evidence commenced and his explanation was accepted as satisfactory. Mr. T..J. Jenkins was chosen as foreman in Mr. Rolls absence and he formally protested against the jury being required to investigate other cases than this of the explosion (they were required to go into the facts of the deaths of two children) the coroner however pointed out that under the terms of his warrant for summoning the jury they could be called upon to investigate any case that might arise.
Mr. John Archibald Constable electrical engineer to the company at Blackwall Point residing at No.8 The Circus, Greenwich was recalled and replying to the Coroner said that the leakage about which he spoke at the first hearing was first discovered in the damaged drain of the boiler on Wednesday, December 19th. It was known there was a slight leakage on the previous Monday, but that was not an uncommon occurrence. A leakage would be remedied by calking.
The Coroner: What was the leakage discovered on the Wednesday?
Witness: It was in the end of the drum, on the extreme right. The leakage was so narrow that it could hardly be discerned and it was only visible on account of the emission of steam. Replying to Mr. Row witness said that before the accident the thought the defect was in the joints and not in the plate of the drum.
Mr. Richard A. McLaren M.I.M.E. works manager for Messsrs. Babcock and Wilcox, Water tube and steam boiler makers of Cannon Street EC and St. Ann’s Square, Manchester, stated that the firm had constructed thermal storage drums for the company. Witness explained the construction of the boilers, drums and connecting pipes, plates of which he produced. He said that the damaged drum was made in 1905 and the accessories in 1902. The drums were 22ft 6 ins long and were manufactured of the best mild steel. All the steel which was purchased by the company from a Glasgow firm, underwent a severe test before being used, having to bear a pressure of 24 to 28 tons to the square inch, the steel was also subjected to a stretching test: a piece of steel two inches in length having to stretch 25 per cent before it could break. These tests were carried out before the steel left the Glasgow works. The drums used by the company were constructed his supervision at the works in Renfrew and before being delivered they were hydraulically tested to a pressure of 240lbs per square inch. The working pressure would be 240 bs per square inch. After being erected at the electric Company’s works they were again tested and nothing was found to be wrong.
The Coroner: when were they tested to 240 lbs? Witness: in July last year. The Coroner: How many storage drums similar to the one in question did your firm make last year. Witness: about 4,000. The Coroner: How many did you find defective? Witness: about twenty were rejected. Replying to the foreman of the jury witness said that the drums were not subjected to a test by the Board of Trade. No doubt the Boiler Insurance Company would be represented at the test after the drums were erected. About nine months elapsed between the making and testing of the damaged drums, but there would be no deterioration. There was not yet a great demand for storage drums, which were only invented eight years ago. The Coroner: Has their been a previous explosion with any to your knowledge? Witness: not to my knowledge. Answering further questions from the foreman witness said that the steel used in the construction of the drums was tested three times before they were used. He could if required produce a certificate that the drum in question was tested at the firm’s works before it was erected. The Board of Trade were not represented at tests. The Coroner: as an expert in steel have you formed an idea as to how the explosion occurred? Witness: It would he impossible I think to form a theory until there had been an examination of the steel. There must be an analysis both microscopically and chemically. The Coroner: it has been said that the steel was brittle. Witness: it may have been. Of course the analysis of the steel would show that.
Dr. William Thompson of London Street, Greenwich, said that he was called to the Company’s works at about five o’clock on 20th December. He described the shockingly mutilated condition in which he had found Mr. Shaw’s body. On the 24th ult he examined the remains of Coombs at the mortuary. The body was almost entirely mangled the remains consisting only of the skull which was smashed beyond recognition and portions of the scalp and face. The trunk and limbs were terribly torn and mutilated.
Mr. Edward George Hillier, BSc M.I.C.E. , M.I.Mech.E., chief engineer in the employ of the National Boiler and General Insurance Company said that he had examined the drum in question and found that both ends were blown out of shape. The detailed how he had found the drum in the Gas Company’s chemical works and that as the result of his examination of the fracture he had formed the opinion that some portion of it existed before the explosion occurred. From the evidence that had been given by Mr. Constable he should say that it was in that portion of the drum where the leakage was describe as being noticed. The coroner: your opinion is that the fracture was a continuation of the crack where the leakage was found. Witness: Yes. The leakage must have come from a fracture. Replying to further questions Mr. Mr. Hillier expressed the opinion that there was an old crack before the explosion and that it extended nearly through the plate going round abut two thirds of the circumference of the drum leaving a third of solid plate. The crack would not be visible from the outside but only when steam was emitted. Asked by the Coroner what he thought was the cause of the explosion, Mr. Hillier, said that the water was kept in the thermal drum at a temperature of 380 degrees and when it had reached the height it could explode – that was to say when the vessel containing it was ruptured. Part of the water might then flash into steam and burst with a tremendous volume of force. Further questioned witness said that when the explosion occurred Mr. Shaw was endeavouring to ascertain whether the crack was in the joint or in the stool itself. Although witness did not see the crack his opinion was that it wad due to some defect in the original plate, or in its treatment in the manufacture. It was possible that either a hard place was formed in the ore of the flange, or a fine crack was there before the vessel was worked. This was the first explosion that had occurred in a thermal storage drum – therefore it was unique. Police Sergeant Jackson, 21 R And Police Constable Moore 140 R having deposed to removing the remains of the two men to the mortuary, Mr. Constable was again recalled at the request of the foreman of the jury. He reiterated that he himself discovered the leak of the 17th ult and the crack two days after, he communicated by telephone with the boiler Insurance Company on the morning of the day the explosion happened. Coombes had reported to witness that there was something wrong the drum. He was engaged when Mr. Shaw arrived in the afternoon to examine the drum. There had been leakage before but the fires were not drawn. The leakage under notice was never regarded as serious or dangerous, but it was unusual because it was in the plate of the drum and not at the joints. Ion answer to Mr. Whale Mr. Constable said he agree with Mr. Hillier that it would have been difficult to have discovered that there was anything wrong until a short time before the explosion.
The Coroner in the course of summing up referred to the unprecedented nature of the accident. Which he said reminded him of the terrible lyddite explosion at Woolwich Arsenal upwards of three years ago when, after considerable difficulty, the remains of the sixteen victims were identified. In the enquiry similar circumstances arose, especially in the case of Coombes, who was recognised by his clothing. The jury after deliberating in private for some minutes returned a verdict to the effect that the two men die from shock as the result of an accidental explosion of a thermal storage boiler. They expressed deepest sympathy with the relatives in their bereavement. The Coroner said he desired to associate himself with the jury’s expression of sympathy and to say how sorry he was that such a catastrophe had occurred.
JANUARY 17TH 1908
THE FATAL BOILER EXPLOSION AT EAST GREENWICH.
BOARD OF TRADE ENQUIRY RESUMED.
At Greenwich Town Hall on Wednesday, Mr. A.A. Hudson, barrister and Mr. J.H.Hallet, consulting engineer, resumed the investigation on behalf of the Board of Trade into the cause of the fatal boiler explosion which took place at the generating station of the South Metropolitan Electric Power and Light Co, Blackwall Point, East Greenwich on December 20th 1906. The case for the Board of Trade was put forward by Mr. George C. Vaux one of the Board’s solicitors. Mr. E.C. Hills represented Messrs. W. Beardmore and Co. who supplied the steel for the drums, Mr. P.G.Nicholls the boiler makers, Messrs. Babcock and Wilcox and Mr. George Whale the electric light company.
The examination was proceeded with of Mr. Andrew McClaren works manager at the Renfrew Works of Messrs. Babcock and Wilcox. The witness said that he had come to the conclusion that the plate where the explosion occurred was brittle. It was not brittle all over but he assumed it was brittle where the fracture was first observed – the place from which, it was said, steam was issuing. He attributed the crack to brittleness thinking that it started where the steam was seen to be issuing and ran two-thirds of the way round. There was no complaint as to these particular plates – there had been complaints as to others, but Messrs. Beardmore’s plates were not worse than those of anybody else. Cracks existed where the indentations existed and they were caused, in his opinion, by a combination of brittle plate and indentation. In a good plate the indentations ought not to have cause the weakness shown in the tests. They ought to be able to indent a plate seven eighths of an inch thick to the extent of an eighth of an inch or more without doing it any damage. Examined by Mr. Hill witness said that when the plates were received they were, as far as he knew, of the best material for the work for which they were wanted. They had frequently sent out drums with indentations as deep as those in the drum in question – no one had attached any importance to them before the accident. He had, however, since discussed the matter with his managing director and they had agreed that for the future it would be better to avoid the indentations. He had heard that one boiler company objected to them. The results of the examination of the plate, wherever there were indentations, were bad, but there were other places where the results were bad too. Distortion of the metal by denting would not decrease the ductility of a good plate. In reply to Mr. Nichollas witness said that they had 42 inspectors at the works several of them engaged on this special work. Severe treatment might cause a crack in the plate if it were brittle but indentations would have no effect on a normal plate. The results of the tests which had been made confirmed him in his view as to its brittleness. He himself had made experiments with a plate taken from another drumhead. Objection was taken as to giving evidence as to the result of these experiments as no notice of the intention to make them had been given to the other parties concerned. Mr. Hudson said that such notice should certainly have been given but witnesses’s evidence was taken. He said that the pieces of this plate were indented much deeper than an eighth of an inch and the conclusion he arrived at as the result of them was that you could indent a good plate as violently as you liked – if it did not stand the dent it was brittle. Mr. Vaux explained that Mr. Carlton who had conducted the tests on the plate for the purpose of the enquiry had been told of the experiments made by the last witness before he conducted his own.
R.H.L.Fernie Inspector of New Work for Messrs. Babcock and Wilcox at the time of the explosion said that he had been inspecting new work for ten years and had examined the drum at the Renfrew works. He saw the indentations but they did not strike him as anything unusual. as he was in the habit of seeing similar indentations. He could not say whether similar indentations occurred in the knuckles of the flange heads of the other thermo-drums sent out by the firm. The indentations did not strike him as being detrimental to the job. He did not think the indentations had anything to do with the crack. He did not know that he would pass the plate now, knowing what had happened. Indentations an eighth of an inch thick would not hurt a plate seven-eighths of an inch thick but he could not say if it would hurt a plate to indent it a little more. If he saw one severely indented he would call the attention of a superior to it if he thought there was anything dangerous in it. The indentations were there because the flange of the shell-plate had come down too far – the plate was too low. Mr. Hudson: Then it was not your duty to call the attention of some one too it. Witness: No Sir. Mr. Hudson: When a plate is too low then it is out of position, is it not? Witness: Yes, but no-one had ever taken exception to it. Mr. Hudson: at what stage would you have taken notice of the indentations? Witness: If I had seen the plate had been stretched in any way or if I had considered there was anything against the plate.
Mr. John Ritchie, steelworks manager to Messrs. Beardmore and Co. a trained steel manager and metallurgist said that there had been no complaints as to other plates made from the same charge as that which failed. He had had a portion of the plate that had failed supplied to him and examined under the microscope there was great evidence of distortion due to the indentations. The cause of the failure was the crack due to the distribution of the metal due to the indentations. He produced a photograph,. magnified to 114 times of a piece of the metal cut through one of the indentations. Witness said that it showed that the metal had been crushed out of its normal condition. Mr. Nicholls complained that no notice had been given that the plate would be tested in this way and at this stage the enquiry was adjourned.
Yesterday morning the examination of Mr. Ritchie was resumed. In reply to the Chairman he said that he accounted for the drums standing a test pressure of 240 lb by the difference in a ‘dead’ load of the test and a ‘live’ working load. He thought the crack began almost immediately the plate ………
24th January 1908
THE FATAL BOILER EXPLOSION AT GREENWICH
BOARD OF TRADE ENQUIRY CLOSED – ALLOCATION OF BLAME
The Board of Trade Enquiry into the cause o the fatal boiler explosion at the generating station of the South Metropolitan Electric Light and Power Company, Blackwall Point East Greenwich, on December 20th 1906 was continued at Greenwich Town Hall on Friday. Several witnesses were recalled and Mr. W.Rosentheim, BA, a metallurgical expert gave the results of his examination of the fractured plate the steel of which he said had been considerably deformed adjacent to the indentations. The material was not quite homogenous but no less so than a large number of other boilerplates, which he had examined – a tendency to segregation existed in most commercial boilerplates. Mr. J.L. Milton chief engineer to Lloyds said that after the accident he had been called in by Messrs. Babcock and Wilcox the makers of the boiler and examined the drum and as soon as possible after the accident the seven other drum end pieces. All were marked with indentations and in all of them the deepest indentations were equally deep with the deepest on of those on the exploded end. He had made study of the fracture of steel boilerplates a special study and there had been numerous cases of the cracking of such plates in the last few years, which had not been satisfactorily explained. In his view the plate in this case was not a normal plate – if it had been he did not think this indentation would have caused the crack. In his opinion the percentage of phosperous in the plate was high.
In the afternoon the Board of Trade Commissioners inspected the scene of the accident.
On Monday the arguments of the three legal representatives of the various parties concerned were heard and on Wednesday morning Mr. A.A. Heard who with Mr. J.H.Hallett as consulting engineer constituted the Commission of the Board of Trade gave the findings of the Commission. Reviewing the circumstances at length he said that they were satisfied that Mr. Shermer inspector of outside work to Messrs., Babcock and Wilcox expressed when he was called in any doubt as to the safety of the drum to Mr. Constable the electric light company’s resident engineer. Mr. Constable would have reported the fact to Mr. Bowden, the company’s chief engineer. It did not appear that the pressure was at the time above the proper pressure of 160 lbs. The works were short of boiler power and Mr. Bowden had told them it would have been inconvenient to shut down the boiler but also that the electricity could have been supplied from the Sydenham station, as it was done in fact, within half An hour of the explosion. It was apparent that both Mr. Howden and Mr. Constable, who Nr. Hudson remarked, gave their evidence straightforwardly never anticipated any danger. The indentations in the plate that gave way were caused by fitting the end plate of the shell of the drum by a hydraulic rivetter exerting a pressure of 160 lbs to the square inch the ‘snaphead’ of which had come partly into contact with the inside of the plate at the’ knuckle’ the end plate having been brought down too low. The Commissioners had no doubt that the indentations showed bad workmanship, which was primarily the cause of the explosion although, as it was stated, the other workmanship in the drum was of the highest class. The indentations were not regarded as of any importance by the boilermakers and if other drums were with end plates in the condition of the end plate in this case they must be now a source of danger. As to the quality of the plate supplied by Messrs Beardmore and Co. The tests had shown that that was of good normal quality the fracture being in no way due to bad material. The plate was satisfactory, the fracture being in no way due to defects in the metal.
Mr. Hudson went on to say that what that Messrs. Babcock and Wilcox supplied a drum with a defectively constructed end plate, injured by rough handling due to bad workmanship. They were therefore primarily responsible for the explosion and had moreover wasted some days of the enquiry in the endeavour to show that the defect was due to bad metal. Mr R.A.McClaren, Messrs. Babcock and Wilcox’s manager was responsible for sending out bad plate. The firm had, however since the explosion, altered their methods of manufacture. Mr. Shermer, Superintendent of Erections, for Messrs. Babcock and Wilcox might have misled Mr. Constable as to his knowledge of boilers, in connection with the opinion he gave as to the leak which was noticed before the accident, but as he was not consulted as to the safety of the boiler he could be held responsible. No one had suggested responsibility against the Electric Light Co. As regards Mr.H.W.Bowden, the chief engineer of the South Metropolitan Electric Light Co., he was a highly qualified electrical engineer but as engineer-in-chief he was also responsible for the boilers and ought to have known there was a danger of explosion in continuing to work the drum. The Commissioners were sorry to have to hold him responsible but it seemed desirable that arrangements should be made in such cases that the engineer responsible for the safe working of the boiler should be someone having good acquaintance with the working of boilers. As to Mr. Constable the resident engineer, he neglected to report the state of the leak to Mr. Bowden directly he discovered it and, when he did report it, informed that it was unimportant. The Commissioners believe that he was acting to the best of his ability at the time he made the report, but thought he must have realised that the drum was in a serious condition and therefore held him responsible. They thought he existence of the indentations should been reported by Mr. Muter the insurance company’s inspector to his company. In fixing the amounts to be made to the Board of Trade towards the cost of the investigation the commissioner had had regard not only to the responsibility of the parties, but in the case of Messsrs. Babcock and Wilcox to the time which had been wasted in enquiring into the condition of the metal plate – their action was unaccountable. Messsrs. Babcock and Wilcox would therefore pay £400, Mr. C. Mclaren, their manager £50, Mr Bowden £50 and Mr. Constable £30 towards the costs of the enquiry. To remove any false impression it should be stated that nothing had occurred to throw doubt upon thermo-storage drums, but if they were badly constructed and not worked in a safe condition accident would happen, as in the case of other boilers under such conditions.
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