Report on the Shrivenham train crash of 15 January 1936/Appendices
Appendix I.
Particulars of Damage to Rolling) Stock of 10.30 a.m. Special Coal Train:—
Vehicle. | No. | Owner and Description. | Damage. |
48th | 53107 | G.L.M. 12-ton Coal Wagon | One long Gedge drawbar hook broken. |
49th | 2961 | Stephenson Clarke. 20-ton Coal Wagon | Metal of bearings fractured, and one end door locking bar broken. |
50th | 4226 | Stephenson Clarke. 12-ton Coal Wagon | 1 Headstack broken. 2 Buffer castings broken. |
51st | 234 | Wallace Spiers. 10-ton Coal Wagon. Registered No. 58958 L. & N.W., 1915. | Completely Smashed. |
52nd | 0841 | Stephenson Clarke. 10-ton Coal Wagon. Registered No. 33808, G.E.R., 1907. |
Completely smashed. |
53rd | 6312 | Stephenson Clarke. 12-ton Coal Wagon. Registered No. 55482, G.W.R., 1923. |
Completely smashed. |
Brake Van | 56923 | G.W.R. 24-ton. | The verandah end, which was trailing, was destroyed, and the wheels were torn from the under frame. |
Formation of, and particulars of damage to, 9.0 p.m. Express, Penzance to Paddington
Engine No. 6007.
Frames.—R.H. main frame, front end, bent (not cracked), standing off inside cylinders ⅜ in., wants rebolting. R.H. footplate wants renewing, front end and back. R H . front corner brackets bent. R.H. hanging bar, bent front and back. R.H. motion plate bent. L.H. main frame. front end, bent and broken. L.H. corner bracket missing. L.H. hanging bar, front end, bent. L.H. motion plate, outside, bent. Buffer bar, box angle iron, angle irons and screw connection, broken.
Cylinders.—All cylinders good. R.H. back cover, broken.
Valve Gear.—R.H. valve spindle, bent.
Reversing Gear.—Reversing screw and box, bent, will not reverse.
Cab—Weather board, cab sides, leg plates, windows, cab handrails, pillars and T, irons, smashed. 4 cone, handrails, top feed pipes R.H. side, all smashed.
Boiler Mountings.—Good.
Sand Gear.—R. trailing sandbox, smashed.
Brake Gear.—Brake hangers, cross stays and rods, smashed.
Bogie.—Both frames bent. Leading cross stay and life guard missing. R.H. bogie centre controlling spring and case smashed. L.H. inside T. springs and hangers all bent. Bogie centre pin casting broken in two webs only.
Springs.—Engine springs good. Spring hanger hrackeb and spring hangers on L.M.D. bent.
Miscellaneous.—Damper gear and cylinder cock gear on footplate damaged. Cylinder cock gear and cocks on R.H. outside cylinder broken off.
Tender No. 2572.—All axleboxes broken. Brake rods, stays and hangers bent. Brake column broken and shaft bent. One brake hanger bracket miasing. Draw gem side and centre links bent. Four handrails and two lamp irons back of tender bent. Tank water indicator gear column broken. Water pick-up scoop broken. Leading and trailing dragboxes damaged. Number plate broken. Intermediate buffers bent. Vacuum pipes damaged trailing end. Vacuum drip trap plate bent. Toolboxes badly damaged. Draghook bent. Middle wheels slightly out of gauge.
Back and front footplates broken and buckled. Right hand side footplate broken and buckled, back end. Two toolbox angle irons broken, right side. Coal door and coal door top broken, right side. Coal door wing broken, right side. Coal plate bent front end, right side. Shovel plate broken. Footboard supports broken. Tank, back end, badly bent, and broken, right and left sides. Tank, back end, inside plates and top angle irons broken.
Rolling stock, all bogie vehicles, screw coupled, electrically lighted:—
Coach No. | Class and Particulars. | Damage. |
4000 | Corridor Third. 8-wheeled. | |
1203 | Newspaper and guard's van. 12-wheeled. |
Wrecked. |
9088 | First Sleeper. 12-wheeIed. |
Both ends of body driven in ; leading end, lavatory and corner extensively damaged; mirror on partition, No. 6 compartment broken; drop window, No. 5 compartment, broken; large window on corridor side centre of coach broken ; and filter broken. 1 broken buffer guide. |
9073 | Third Sleeper. 8-wheeled. |
Leading end of body driven in. 4 bent buffers. |
4606 | Brake Third. 8-wheeled. |
2 bent headstocks (slight) on underframe. 2 bent buffers. |
7756 | Composite. 8-wheeled. |
2 bent buffers. 1 bent drawbar. |
3484 | First Sleeper. 12-wheeled. Tare 42 tons 13 cwt. Built 1929. Length 63 ft. 6½in. Underframe, steel. Body and roof, wood framing and steel |
1 large window broken. 2 shghtly bent headstocks on underframe. 2 bent buffers. 1 bent drawbar. 1 coupling screw bent. |
9070 | Third Sleeper 8-Wheeled. Tare 35 tons 5 cwt. Built 1929. Length 63ft. 6½in. Underframe, Steel. Body and roof, wood framing and steel panels. |
1 door off its run. 2 bent headstocks (slight). |
3484 | Brake Third. 8-wheeled. |
1 Coupling screw bent |
Appendix II.
Broken Drawbar Hook From G.L.M. Wagon No. 53107—Accident at Shrivenham, 15/1/36
I give below the results of my examination of the above broken drawbar hook
Description of fracture.
The hook broke in the position shown in the attached sketch in a plane at an angle of approximately 60 degrees to the axis of the drawbar. the fractured surface. having the appearance of a typical shock fracture. The cross-sectional area at the point of fracture was 5.9 square inches.
The whole of the face of the fracture was bright and had a coarsely crystalline appearance with the exception of a portion measuring 4 in. by 8 in. which extended inwards from the surface at the top of the hook. This area was covered with an oxide film and appeared to be a flaw which had been in existence for a considerable time and was produced probably during manufacture of the hook.
Chemical Analysis.
Analysis of the material adjacent to the fracture gave the following results:—
Carbon | 0.02 per cent. |
Silicon | 0.127 per cent. |
Manganese | 0.08 per cent. |
Sulphur | 0.016 per cent,. |
Phosphorus | 0.276 per cent. |
These results prove the material to be wrought iron. The proportion of phosphorus present in rather high, but not higher than is found frequently in iron having good physical properties.
Physical Tests.
Test pieces cut from the hook as close as possible to the fracture and in a direction parallel to the axis of the drawbar were tested with the following results:
Breaking stress, tons per sq. inch on 0.25 sq. inch area | 21.6 |
Elongation on 2 inches, per cent | 31.5 |
Contraction of area, per cent. | 39.2 |
Yield Point, tons per sq. inch. | 11.6 |
Ratio of Yield Point to Ultimate Stress, per cent. | 53.7 |
Izod Shock Teat, foot lb. | 10.2 |
10.2 | |
Brinell Hardness Number | 118 |
A machined test piece measuring l½ in. by ¾ in. by 7 in. cut from the hook in a direction parallel to the axis of the drawbar broke when bent cold through an angle of 80° over a round bar 2½ in. in diameter.
The results of the tensile test are satisfactory for wrought iron of good quality. The Izod figure, however, is very low, being less than a third of that given by good quality iron. The result of the bend test is poor.
Macrostructure.
A sulphur print prepared from a transverse section adjoining the fracture showed the characteristic uneven distribution of sulphides normally encountered in wrought iron. In no part was there any indication of unduly high sulphur segregation.
Macro-etching revealed lack of homogeneity of the material and the presence of wide boundaries containing large slag inclusions between adjacent areas of iron having different grain sizes.
Microscopic Examination.
The microscopic examination of polished and etched sections showed that the metal contained a considerable amount of slag which was present in rather large masses unevenly distributed throughout the material. The shape, mass and distribution of these slag inclusions indicated that the metal had not been subjected to sufficient forging to produce the degree of homogeneity which is desirable. The grain size of the iron varied in different parts of the section, but was generally very large and suggests that the metal was overheated during forging.
Conclusions.
The results of my examination indicate that the wrought iron of which the hook was made was of fair quality chemically, but that it had been insufficiently worked to produce homogeneous material free from coarse slag inclusions.
The hook appeared to have been heated to a high temperature during forging which resulted in the production of a very coarsely crystalline structure to which the poor shock-resisting property of the metal, as shown by the low results of the Izod Test, is chiefly due.
The existence of the small defect in the hook, to which reference is made in the description of the fractured surface, was, in my opinion, a contributory cause of the failure, resulting in the production of "notch brittleness" at the low temperature existing at the time the fracture occurred.
R. W. Dawe.
Appendix III.
Rules and Regulations Applicable to Goods Guards.
148.-(b) The Guard of a goods train must keep a good look-out and should he see any reason to apprehend danger, he must make every effort to attract the attention of the Driver.
If there is any Danger to & train on an adjoining line, the Guard must, should his train pass a signal box, exhibit to the Signalman a red hand signal waved slowly from side to side, and the Signalman must, on receiving this signal, act in accordance with Block Regulation 17.
(d) In the case of trains not fitted with the continuous brake, the Guard must, unless special instructions are issued to the contrary, always apply his brake as soon as he becomes a ware that the Driver is applying the engine brake.
Rules and Regulations Applicable to Enginemen.
126. The Driver and Fireman MUST:
(viii) observe signal boxes when passing them and look back frequently during the journey to see that the whole of the train is following in a safe and proper manner.