US2259669A - Nozzle stopper - Google Patents

Description

01.21, 1941. I RLSWANK 2,259,669

' NOZZLE STOPPER Filed July 18, 1941 INVENTOR P04 PH L Swen/K ATTORNEY -tries; as sleeves or stopper rod sleeves.

Patented Oct. 21, 1941 OFFICE;

V This invention relates to the construction and manufacture of nozzle stoppers, or stopper rods as they are sometimes referred to in the steel foundry industry, for controlling the pouring of molten metal from ladles into ingot molds or flasks designed to give the shapes of castings wanted. a r

The ladle forholding the liquid must of necessity not leak and provision must be made for the removal'of the liquid'through a hole left in the'bottom of the ladle. The flow of this liquid must be controlled in order that the ladle may be movedfrom one mold to another without spillage, until the ladle is emptied of its contents. To accomplish this the stopper rod is used and on the end of this rod is placed a head usually of carbon or clay designed to adjust itself properly on the seat of the nozzle. The stopper rod is operated by a man from the pouring platform by means of a lever which gives the stopper rod a raising and lowering'movement. W'hen raised the nozzle opens to allow the metal to flow and when loweredthe flow. of metal through the nozzle is shut Qfifg The stopper rod beingiof steel would melt and be uselessunless protectively covered by a refractorymaterial. Heretofore the protection has been provided by sections of refractory material of various sizes which are commonly known within the refractory, steel and foundry indus- Such sleeves are commonly provided with a male and female joint as component parts of the body of the sleeves and with attendant exacting dimensional limitations to permit of their properly fitting together. Whenever the joints as described do not fit properly, the operators seldom try to use the sleeves due to the risk involved of molten steel infiltrating through the joint and attacking the steel rod itself and burning it off, causing loss .of control of the flow of the remaining metal in the ladle through the nozzle with resultant monetary loss and. in instances the severe burning of workmen with fatal results. No consumer of sleeves would knowingly use sleeves with the male and female joint not properly fitting and thereby endanger property and human life. With this type of joint severe accidents can happen and have happened. Only one defective sleeve joint on a stopper rod, which may not have been noticed during assembly, is enough for complete spoilage of the ladle contents. Furthermore, the use of the male and female type of joint on a sleeve, permits of no flexibility in the use of that sleeve along with other such sleeves of different dimensions. Sleeves as heretofore producd, with themale and female joint. are'made with various outside diameters, such as 4-",- 4

4 5", 5 5 5%", 6" and larger, also some in-between sizes, each carrying a male and female joint of different dimensions and proportions. This practice has precluded the use of one size of sleeve with another size sleeve on the same stopper rod assembly. Furthermore, the maleand female joint types of sleeves are quite susceptible to breakage or damage before assem- 161,644 and Andrew J. Haws No. 205,084, the latter showing the commonly employed male and female type of joint. I

By virtue of the invention herein described, the male and female type of joint with its inherent disadvantages is eliminated. Instead the sleeve is made with an indenture at each end which is not necessarily of one particular sizeor shape but is centrally located to enlarge the hole at the sleeve end. A number of cross sectional shapes of the hole in the sleeve can be adopted with attendant advantages but without affecting the utility of'the stopper rod assembly or detracting from the efiiciency of the joint. In assembling sleeves, indented in this way, on the stopper rod, the'cavity provided between adjacent sleeves by the juxtaposed indentures, is filled with plastic refractory material. Precise or even approximate registry of the indentures is not necessary. This material when dried forms an effective seal ,at the joint and serves to support the sleeves concentrically at their ends upon the steel rod.

Thesleeves used in this new stopper rod assembly'are, preferablyformed by the extruding method which is most economical and by subsequent grinding of the indentures at the sleeve ends. On the other hand there is no known way to produce the old male and female type of joint other than by pressing the sleeves in a mold. Any attempt to grind the male end would result in the grinding tool tearing or shattering the protruding dried clay part of the sleeve at that end.

The process of making the sleeves with indentures at both ends is as follows: A perforated column of plastic refractory material is extruded and squarely cut off into sleeve lengths or secsleeve.

tions while in the plastic stage. The individual sleeves are then dried and the centrally positioned indentures are formed by suitable grinding tools. Both ends of a sleeve may be thus formed in one operation. When so formed the sleeves are baked in a kiln.

The hole through the sleeve is preferably noncircular in cross section. It may, for example, be fluted, thus insuring ample air Docket space between the rod proper and the surrounding The fluting of the interior surface of the sleeve adds strength with a saving in weight of the material. The fluted hole can readily be formed in the extruding step. Because of the safety features contributed by the joint, sleeves made in this way, i. e., by the extruded and grinding method may be formed 'in greater the sections of heat from the molten metal to the rod ll. When the clay is dried out it forms,

together with the sleeves, a complete and efiec-' sections and then grinding indentures at both ends thereof. After being thus formed the sections are baked to prepare them for use as hard refractory sleeves. Usually with thesteel rod held horizontally, the head is first fastened lengths than is practical with the old male and female type of sleeve.

A description of a stopper rod assembly em bodying the invention follows, with reference; to the accompanying drawing wherein; I

Fig. 1 illustrates a portion ofa nozzlestopper assembly, partly in longitudinal; section, 3

Fig. 2 is a cross sectional view n the line 2 2 ofFig.1. Figs. 3 and 4 are views similar to Fig. 2 show ing practical variations. in the cross sectional shape of the hole in the sleeve, and W Figs. 5 m9 are fragmentaryviews' -in longitudinal section showing several practical: variations of shape of the indentures at-the ends. of the sleeve. l I I p A steel rod H for-raising and lowering a. head l2 secured to the lower end of? the rod by a bolt I3 is protected throughout that part of its length which is to be immersed in. the molten steel; by a series of sleevefs'ections. such as l4, l5 and I6 which abut one another'end to. end. lEachsleeve preferably has a holefluted in crosssection, as shown in Fig. 2, or the'hole may be round in cross section as shown in Fig. 3, or be of polygon. shape as shown in Fig, 4'. The. advantages of; the noncircular hole in the sleeve. are that air pockets I-D' still will be maintainedat any side of the rod should it ben'd' that way. Atjthe'sainei time with a given amo'unt'of' air smegma re better held against excessive bending thahby a sleeve having'a round hole; i

The indentures at the. endlofi the tions maybe. oi bevel shapeas. shown; at li'llin Fig. 1, simple concavefas shown, at" [8 in Fig. 5, convex, as shownat I9 inFi'g'. djbevelwith' a notch 20 in the beveledfsurface and a. notclil'l in the end' surface, as shown in "(,f concave with anotch 22; in the conca e'surfacaas shown in Fig. 8, or convex'with a' notenza'm theconvex surface, as shown in Fig. 9;; These several shapes at the sleeve ends are of a. like'character in that they all provide centrallyj positioned, indentures that, when in' juxtaposed positionsgfo'rm cavities. These are filled with plastic refractory material such as clay 24- to' obstruct thj'elentrance between sleeve" See'- thereto at oneend. The workman then wipes plastic clay over the end of the head and shoves a sleeve over the other end of the rod, pushing it on until it meets with; the head. Hethen applies enough plastic clay to the following and of thatfirst sleeve to fillacavity provided by two juxtaposed indentures and shoves on another sleeve until itmeets with the first. one. This causes the plastic clay 24 to be molded into the cavity, which is thus filled completely. Alittle of the clay may squeeze in between. the abutting end surfaces of the sleeves, as at 25, and more will flow into-contact with the steel rod adjacent the joint. When the rod is thus fully covered by sleeves and plastic. clay in this manher, a nut on the threaded upper end oftherod is drawn down to push the sleeves together-and hold' them in place... Then the rodis: placed in a. drying oven after which it is ready to be hung in the ladle to receive the molten metal whenthe nut may be released'somewhat ta permit of thermal expansion. 5

'I claim:

1. In a nozzlestop'per for ladles, the combination with a rod,.of a series of, perforated sections of baked refractory material covering said rod, each of said sections having indentures centrally positioned at each end thereof. and plastic refractory materiaffillihg. the. cavities between adjacent sections provided by suchindentures.

2. In anozzle stopper forl'adles, the combination with a rod, of a series. of perforated. sections of baked refractory material concentrically embracing said rod and substantially covering it lengthwise, the cross-sectional area of the per- 'forations of said sections being greater than the cross-sectional area. "(if said rod, each. of said sections having inden'tures centrally positioned

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