US1659775A - Splice bar - Google Patents

Description

Feb. 21, 1928. 1,659,775

c;` LANGFoRD lSPLICE BAR Filed April 25. 1927 Patented Feb; 21, 1928.

UNITED vSTATES PATENT OFFICE.

GEORGE LANGFORD, OF JOLIET, ILLINOIS, ASSIGNOR TO MCKENNA PROCESS COMPANY OF ILLINOIS, OFJOLIET, ILLINOIS, A CORPORATION OF ILLINOIS.

' sPLrcn Baa.

lateral and longitudinal movement. The advantages of thus anchoring the rails are obvious and well known. Great difficulty has been experienced, however, in anchoring the bars to the VVties in the manner stated due to what is known as flange breakage or failure of the bar. After the b ar has been in use forI a short time, due to the severe strains and stresses to which it is subjected, a crack de- Velops at the inner corner of the innerI one o the spike slotsand gradually extends to the adjacent center or inner one of the bolt openings from which it extends tothe center of the barr'esulting in breaking of the bar in two. Toovercome this difficulty, in some of the bars: of older types, the flan e portion has been materially thickened, an in others the flange has been widened to rovide closed slotsxn".vv` openings for the spikes.y In still others fillets have been provided 'at the slot corners. The filleting of the slot corners has not proved successful 'and the widening of 'a5 .the base flange to provide closed spike slots has also failed to insure. against reakage. By making the base flange unusually thick and heavy, it is possible to avoid, to a great y p extent, this flange failure or breakage, but

i 40 tliis is objectionable as very materiallyl in- ,creasing the weight andthe cost ofthe bar. The widening of the base flange to provide closed spike slots is also objectionable for the same reason. -f

The older types ofbars above referred to are being discarded in favor of what is known as the balanced I-beam or 100% splice bar. This bar is so constructed that the area of the metal above the neutral zone, which is the plane of the axes of thesecuring bolts, is approximately equal to the area 'of the metal below such zone. Constructing the bar in this manner provides an equal distribution of the metal above and belowV the neutral zone so as to balance the resistance of the upper and lower portions of the bar'to the strains and stresses to which it is subjected, insuring maximum efficiency. This type of bar is generally recognized by railroad engineers as closely approaching the ideal splice bar and possessing very high efliciency, and has come lnto extensive use. This bar, has, however, one objection. In order to properly balance the bar at opposite sides of the neutral zone, as above stated, the base flange of the bar is necessarily relatively thin and it is not practical to materially increase the thickness of this flange, as to do so would destroy, to a great extent, the high efficiency of the bar. This renders it impossible, from a practical standpoint, to thicken'the base flange lsufficiently to prevent flange failure or breakage of the bar, as was formerly done in the older types of splicev bar. I have found that this objection can be overcome by properly disposing the spikev slots in the f flange of the bar. My invention, therefore,

relates primarily to the disposition of the spike slots in the base flange of a splice barhaving a comparatively thin' base flange, in such manner as\to. prevent breakage of the bar due to the provision of the slot. More particularly, my invention is intended for use with what is known as the balanced I-beam or 100% type of splice bar.

Further objects and advantages will appear from the detailed description.

In the drawings?- j j y Fig. 1 is a transverse sectional view through a splice bar of the balanced -I-,beam

. l i Y Fig. 2 is an outer face view of the -bar rovided with spike slots arranged in ac' cordance with the present practice;

Fig. 3 is a.vie w similar to' Fig. 2 showing the' bar provided with spike slots arranged in accordance with my invention.

The. bar 1 is provided with a base flange 2`of a width to project beyond the base flange of the rail, as shown inFig. 1. This flange is provided in` its underface with a recess 3 providing what isvcalled an easement in order that the bearing surface of' the baron the rail flangey shall be approximately equal to the bearing surface of the head of the bar .on the rail head. This bar is provided, through the web portion 4 thereof, with two central bolt receiving openings 5 and two end bolt openings 6 wh1ch are related in the usual manner well known'in this 110 loo art. The bar is further. provided with two spike Areceiving slots 7 and 7a which are arranged in accordance with the present practice. By referring to Fig. 2 it will be noted that slot 7 Vis disposed within the space between the left hand opening 6 and the adjacent center opening 5; that is, the inner bolt slot is disposed within the space between the adjacent end bolt opening and the ad'acent center bolt opening. The other s ike slot 7 a is disposed well beyond the other olt opening 6 and closely adjacent the right hand end of the ba-r. It is the practice to dispose the spike slots in this manner in order that the spikes at opposite sides of the joint may be disposed in ystaggered relation thus avoiding possible splitting of the tie, such as might result if the spikes were in alignment. I have found that the disposition of the spike slot 7 Within the space between the bolt openings 6 and 5, as illustrated, andin accordance with the common practice, is responsible for what is commonly known as fiange failures oi' breakage of the bar. I

This fact has not been recognized by the railroad engineers and, due to the large percentage of fiange failures or breakage in bars of this type, some engineers have discontin ued providing. the bars with spike openings,

preferring to sacrifice the advantages of anchoring the rails to the ties in order that bars of this'type can be used.

When a rail joint is new the area of strain lies between the two center bolt holes which are, ordinarily, spaced about six inches apart, though this spacing can be varied.l

As thel bearing surfaces of the rails and the bars wear, the areaof strain extends toward the endsof the bars to include, that portion of the bar in'which the inner spike slot 7 is located. In practice the area of strain does not extend toward the ends of the bar beyond the two bolt holes next to the center holes; that is, in the bar illustrated, beyond the bolt holes 6. `As the inner slot 7 is disposed within the strain area and, in view of the fact that this slot weakensl the flange .2, a crack, indicated at c, develops at the inner corner of slot 7 after the bar has been in use for a short time. With continued use of the bar this crack extends to theq'adjacent bolt hole 5, since the greatest strain is at the center of the bar, and the stresses to which the bar is subjected extend from the center of the bar at the top thereof diagonally downwardly and outwardly to the inner corner of the bolt slot 7. This crack 0 greatly weakens the bar and it quickly fractures along the line c', extending from the bolt hole 5 to the center of the har at the top thereof, this completing the breaking of the bar. A further fault resulting from arranging vthe spike slots in the manner illustrated, in accordance with present practice, is that the slot 7"L is disposed so closely adjacent the end of the bar that the portion of the flange beyond this slot frequently breaks off along the line c due to strains to which it is subjected by creeping of the bar, or beclause of expansion and contraction of the rai s. ,i I

I have found that the objections above noted can be overcome by disposing the spike slots beyond the strain area of the bar, that is, beyond the spaces between the end bolt holes 6 and the center bolt holes 5, the spike slots being disposed between said spaces and the ends of the bar. In Fig. 3 the spike slot 7 is disposed beyond the horizontal center of the adjacent bolt hole 6 toward the adjacent end of the bar, and the slot 7a is disposed inwardly towardrthe adjacent bolt hole 6 relative to the corresponding slot 7a in Fig. 2, but is located be tween the adjacent end of the bar and the bolt hole. In my bar both of the slots 7 and 7a. are disposed beyond the strain area of the bar. Thestrain area is limited by the bolts extending through the end bolt holes 6 and does notl extend beyond the end bolts, even when the joint is badly worn.

disposing the spike slotsin the mannen illiistrated, beyond the strain area, the bar is not weakened within they strain area and, as a result, flange failures are eliminated. It will also be noted that'the slot 7a is disposed suiciently remote from the adjacent end of the bar to eliminate the less serious breakage alongthe line c. v Bars with the spike slots arranged in accordance with my invention eifectually eliminate all danger ofy breakage due to the provision of the spike slots, rendering it possible to employ the balanced I-beam or 100% type of bar.' with the additional advantage that this bar can bev spiked to the ties for anchoring the rail 'and disposed between the ends of the bar and the respective end bolt holes.

In witness whereof, I hereunto subscribe my name this 4th da'y' of April, 1927.

GEORGE LANGFORD.

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