1819.] 



THE CIVIL ENGINEKR AND ARCHITECT'S JOURNAL. 



S3£ 



6, c, d, e, the plate /, is taken off, and the pipe or cylinder is re- 

 moved from the mould. 



The apparatus employed for castina: circular-shaped hollow 

 vessels is represented, in sectional elevation, at fig-. 4. It consists 

 of a framing n, in which two shafts o, p, are mounted; to the shaft 

 0, motion is given by a band passing around the pulley q; and this 

 motion is transmitted by the bevel-wheel r, and pinion s, to the 

 upright shaft ;), which carries the mould t. On the upper edge of 

 the mould an annular plate ti, is bolted, to retain the fluid metal 

 during the revolution of the mould, and to admit of the casting 

 or vessel v, being removed when the metal has become sufficiently 

 set. At the bottom of the mould is formed a socket, to fit upon 

 the top of the shaft p; so that, when placed thereon, it will accom- 

 pany the shaft in its revolution; and tlie mould may be readily 

 removed from the shaft and replaced thereon, w, w, are the 

 handles by which the mould is lifted. 



METAL CASTINGS. 



David Henderson, of the London Works, Renfrew, Scotland, 

 engineer, for ^''improvements in the mnniifiicture of metal castings." 

 —Granted March 20; Enrolled September 20, i84.9. [Reported 

 in the Patent Journal.^ 



This invention has reference: First — to the manufacture of 

 pipes, columns, girders, and other similar castings, presenting an 

 uniform section throughout the whole or greater part of their 

 length, by means of a short moveable part pattern, and also in close 

 mould-boxes. Secondly — To the casting of pans, basins, or other 

 like circular figures, by means of part patterns, in moulds formed 

 in close mould-boxes. Thirdly — To the producing a succession of 

 castings, of the uniform section mentioned, from the same mould, 

 without destroying it at each casting, as is usually the case. 



In the manufacture of castings of the kind mentioned (having 

 an uniform section throughout) he employs what he terms a close 

 mould-box, instead of the ordinary box used, which is open at the 

 back; the sand or loam being rammed from tlie back. This mould 

 consists of two parts, as usual, dividing at tlie centre line, in the 

 case of small pipes, representing two halves of the tube, each hav- 

 ing numerous small holes bored through them to allow the air and 

 gases to escape. Each half-mould is furnished with two internal 

 lips or flanges, of the full length of the mould, which project 

 towards the centre, their inner edge being suited to the external 

 form of the casting; or they may he of a breadth that will admit 

 of a slight thickness of sand between the edge and the casting. 

 These lips form a secure hold for the sand constituting the mould, 

 which in the upper half (with the mould in a horizontal position) 

 may be said to represent the abutments of the arch formed by the 

 sand. The lips are carried out thin, or tapered towards the centre, 

 and planed or otherwise rendered true on the face, so that they 

 may fit accurately together to form the entire mould. The pattern 

 employed to form the body-part of the mould consists of a short 

 semi-cylindrical piece, having a plate on the flat side or back of 

 the part pattern, which slides on the dividing surfaces or lips of 

 the mould, retaining it always in the same central position as it is 

 travelled throughout the length of the mould, and may either be 

 held at the difl'erent positions required, by bolts at the edges, or by 

 clumps embracing the hack part of the lialf-moulds. In commenc- 

 ing the moulding, the mould to form the socket or lower end is 

 introduced, and the sand rammed round it from the top; the part 

 pattern is then placed in a position immediately above the socket 

 part, and the sand rammed in the space left between the pattern 

 and mould-box, the previously-rammed sand of the socket part 

 closing the bottom of the space. The part pattern is then raised 

 a step higher, and the operation repeated, and continued through- 

 out the whole length of the mould, which is afterwards surmounted 

 by a jet-piece or mould, into which the metal is poured. If the 

 spigot end of the pipe is furnished with a bead, it is produced at 

 the junction of the mould with the sand in the jet-box, one-half 

 being in each; that in the mould being produced by a half-bead on 

 the upper end of the part pattern, and the other formed in the jet 

 part of the mould. Two half-moulds thus formed are placed and 

 bolted together by clumping-rings, or other suitable means, and a 

 core introduced in the ordinary manner, and sustained in a central 

 position at either end. In this manner various other articles may 

 be formed, such as columns, girders, gutters, and other like cast- 

 ings; using the half or single mould-box for such purpose, with 

 the projecting lips, and a plate for the other half, faced with sand, 

 having a core or internal figure of the gutter. Cornices, and other 

 like figures, are also capable of being moulded in a similar manner; 

 the muuld-box in each case being suited to the- shape of the article, 



so that only a thin uniform or nearly uniform coating of sand i» 

 required on the interior to form the mould. An example is also 

 given of a grooved roller or pillar, having sharp angular grooves 

 running throughout its length, which in the ordinary mode of 

 casting would require a complicated pattern to produce the mould, 

 whereas it may be formed as readily as a plain casting by this mode 

 of operation. Moulds of this description maybe formed in mould- 

 boxes, without lips, to retain the sand, the edges of the box being 

 planed true and out of winding to ensure accuracy in the sliding 

 of the part pattern, which is guided by pieces that embrace the 

 sides of the box, and are carried out to its full length. 



In all castings having their interiors formed by cores, the ordi- 

 nary modes are resorted to for carrying such part into efl^ect. In 

 pipes or cylinders of the larger sizes, it may be advantageous to 

 divide the boxes into three or moi'e parts, in which case, each 

 division is provided with lips, as before explained, which will retain 

 the sand in each individual part. Bend pipes are also represented; 

 in this case the mould-box is divided in the centre line, at the 

 sides of the bend, and suitably faced and lipped at the junction, to 

 admit of tlie correct worl<ing of the part pattern, which is curved 

 to correspond with the curve of the bend. The outer lialf of the 

 bend is placed on a foot, so that the socket projects in a horizontal 

 direction, suitably furnished with guide-pins, to ensure the parts 

 of the mould meeting correctly. 



The second part lias reference to the casting of pans and otlier 

 basin-like shapes. This is effected also in close mould-boxes, 

 somewhat appri'aching the shape of the pan to be cast, having a 

 number of perforations, as before explained, and also with an in- 

 ternal flange or lip projecting towards the centre, the distance of 

 the said coating. A pin stands up in the centre of the pan at the 

 bottom, on which is placed a part pattern, — that is, the lower end 

 is stepped on it, the part pattern being perhaps 3 or 4 inclies 

 broad, and carried up to the edge of the mould-box, where it is se- 

 cured. This pattern is on the side next tlie box of the form to be 

 given to the exterior of the pan, and between the pattern and the 

 pan is the space to be filled with sand or loam. When first com- 

 mencing the operation, one side of the space is closed with a board 

 until the first breadth of the pattern is complete, when it is un- 

 bolted at the upper or lip edge of the mould-box, and the pattern 

 moved nearly its breadth in the direction of the circumference, 

 in which it will be guided by the central pin on which it works, 

 and the part bearing upon the lip; the ramming is then con- 

 tinued, — the previously-formed part of the mould forming the 

 stop against which the successive breadths opened are pi-essed. 

 In this manner, the whole circumference of the interior is lined, 

 wlien the outer half of the box will be ready to receive the 

 internal part of the mould which is formed on the exterior of 

 a similarly-shaped mould-box, and produced by a part pattern in 

 the same manner as the other; but with this difference in the part 

 pattern — that it is the reverse of that used for the other box. The 

 lialf-moulds or external and internal parts, so formed, are then 

 placed together and secured in the ordinary manner, when suitable 

 jets are produced in the sand for the introduction of fluid metal. 



The third part of this invention refers to the production of suc- 

 cessive castings from the same mould, — that is, without destroying 

 the form of the sand of which it is composed, but which is only 

 applicable to such articles as pipes or otlier plain castings easily 

 removed from the mould; in which case he employs close mould- 

 boxes, having lips which retain the sand. If the casting is re- 

 moved with care, which is to be done immediately the metal has 

 set suflRciently for that purpose, after the black-wash with which 

 moulds are usually coated has been scraped off, the several parts of 

 the mould which have been injured are then to be made good, and 

 the black-wash repeated while the mould yet retains sufficient heat 

 to dry it. Moulds used in this manner should be of dry sand or 

 loam and care taken in the removal of the casting and repairing at 

 each time; thus several castings in succession may be produced 

 from the same mould before its total destruction is necessary. 



VALVES AND COCKS. 



Peter Llewellin, of Bristol, brass and copper manufacturer, 

 and John Hemmons, of the same place, brass-founder, for ^^im- 

 provements in the manufacture of cocks or valves for drawing off 

 liquids."— Grantei November 23, 1848; Enrolled May 23, 1849. 



The improvements relate to the introduction of a screw or disc- 

 valve in cocks, to render the same steam and water-tight. The 

 valve is raised for closing the way, or lowered for opening the way, 

 by means of a hollow screw in the rotary stem of the handle; 

 which screw acts upon the disc-spindle. By the turning of thi« 



