114 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL 



[AruiL, 



patentees empldy a mandril or trililet of the intended form for the 

 tul)e, on which a piece of sheet-metal is placed, w)iich lias heen 

 roiifjhly turned up somewhat near the form, which is then to be 

 drawn tlirough the die or draw-|)late, of a shape corresponding' 

 with tlie mandril or trililet; but tliis draw-plate, unlil<e the ordi- 

 nary draw-plates, is made of a soft yielding material, w liich gra- 

 dually expands as the tube is drawn through it, the opening 

 thereby becoming gradually larger; whereas, in the ordinary 

 draw-plates, the opening through which tubes are drawn is jierma- 

 nent, and finishes the tube of an exactly similar diameter to tliat 

 which it commenced. Fig. 1 represents an end view of one of 

 these improved draw-plates or collars; and fig. 2, a longitudinal 

 section; this is constructed to draw a taper tube, riuted through- 

 out its length, and is made of tin, which they find answers the 



Fig. 1. 



Fig. 2. 



purpose extremely well. It is made of a sufficient thickness to 

 witlistand the pressure necessary to the drawing the tube of the 

 required form, which will in a great measure depend on the thick- 

 ness of the metal to be drawn. The rough tube having been 

 placed on the mandril, is drawn through this metal collar, which 

 is placed in a holding-plate in the drawing-bench. This appa- 

 ratus, being of the ordinary kind, it is not necessary to give any 

 description thereof. The small end of the tube is held by the 

 drawing nippers, and as it is drawn through the metal collar,' it is 

 gradually drawn into form as it passes through it, and when issuing 

 from the other side, is compressed to, and assumes the shape of 

 the mandril, and tliis being of a hard and rigid material, the 

 collar is expanded according to such shape; thus delivering the 

 tube tapered and fluted in as perfect a condition as if it were a 

 parallel tube. It will be readily understood from this how the 

 other forms shown are produced, with the exception of E, which 

 involves another arrangement. This tube, it will he seen, differs 

 from the foi-egoing, inasmuch as the Hutes, instead of running in 

 the direction of its length, are carried spirally round the tiibe. 

 This form is produced either by causing the drawn collar to turn, 

 or else suffering the mandril to turn as it passes through the 

 collar. For this purpose, they prefer the latter mode, which is 

 effected by placing the mandril or triblet, on a spindle, the head of 

 which takes on the back end of the mandril, while the point pro- 

 jects through at the other end, and is laid hold of by the drawing- 

 nippers, instead of the tag-end of the brass, as usual. In this 

 mannei', the mandril and tube is drawn through the collar, while 

 at the same time it is carried round by the spiral flutes in the 

 mandril, the soft metal collar effecting the same purpose as in the 

 last case — deli\ering the tube completely formed on its mandril, 

 which is then withdrawn, being readily efl'ected by turning the 

 tube sliglitly on the mandril. In this way may various other forms 

 of taper tubes be produced, the small end, of course, being always 

 drawn through the collar first, the collar in all cases adapting itself 

 to the mandril, where there is no conti'action of tlie mandril at 

 any point to a size smaller than that which it has previously 

 passed. 



The second part of this invention has reference to the manufac- 

 ture of brass tubes, for the passage of gas, which consists in 

 simply drawing one tube within another, for the purpose of giving 

 greater security to tlie joint, which, in tlie one, is diametrically 

 opposite to tliat of the other; thus, if any leakage occurs in the 

 inner one, it will be effectually sealed by the outer tube. The 

 mode of drawing these double tubes is by simply drawing the 

 inner tube of the proper size, then placing the e.xternal tube on 

 it, which is large enough to slide on easily. The compound tube 

 is now drawn tlirough another jilate, which contracts tlie outer 

 one on the inner, and may virtually be said to be one tube. This 

 may eitlier lie efl'ected with or without the internal mandril or 

 triblet usually employed, and well known in the drawing of brass 

 and other tubes. 



Having described the nature of their invention they would have 



it understood that they do not confine themselves to the precise 

 detail, as such may be varied without departing from their inven- 

 tion; liut what they claim is: First — the manufacture of taper 

 tubes, by pressing a roughly-formed tube into contact with a 

 mandril in its interior, the said pressure being exerted by a ring 

 or mould, made of a material which will yield or expand as the 

 tube is drawn through it, but exerts sufficient pressure to force 

 the jiartially-formed tube into contact with the mandril, whether 

 the said expanding ring or mould be of the form, and used in the 

 manner described, or have a different form, or to be differently 

 used, and whether the said taper tubes have any of the forms de- 

 scribed and represented in the annexed engravings, or have any 

 other form. 



Secondly — the manufacture of gas fittings of double tubes, as 

 herein described. 



IRON BARS. 



Richard Shaw, of Gold's-green, West Bromwich, Staffordshire, 

 railway-bar finisher, for '■^improvements in the niiniujhcture of iron 

 into tyre-bars, romid bars, square bars, and flat bars; tee-iron, angle- 

 iron, and trough-iron." — Granted August 21, 18+8; Enrolled Feb- 

 ruary 21, 184.9. [Reported in the Patent Journal.'] 



This specification, wliich relates to the manufacture of iron, 

 consists of various modes of forming and arranging the bars con- 

 stituting the piles for rolling into— first, tyre-bars for tyres of 

 railway-wheels; secondly, round bars, square bars, and flat bars; 

 thirdly, tee-iron; and fourthly, angle-iron and trough-iron, in 

 place of arranging tlie bars forming the pile, so that the edges of 

 them shall appear when rolled or manufactured; thus preventing 

 the joints of the bars impairing the strength of the article made, 

 and liable to be much laminated from use. The patentee forms 

 the piles of bars bent and arranged in such manner that only tlie 

 sides of the bars shall be presented at the exterior of the article 

 made, preventing thereby to a considerable extent the lamination 

 taking place, and increasing the strength. 



Fig. 1. 



Fig. 2. 





Fig. 4. 



Tlie annexed cuts show the modes of piling described by the 

 ])atentee for forming the above-named articles: Fig. ], being the 

 section of a pile arranged for making tyre-bars, and a section of 

 the tyre rolled from it. Fig. 2 is a section of a pile for making 

 square, round, or flat bai-s. Fig. 3 is a section of a pile for making 

 tee-iron, and a section of the tee-iron made from it. Fig'. 4, 

 sections of a pile for making trough or angle iron, and of the 



