US2003094A

US2003094A - Metal article and method of preparing same

Info

Publication number: US2003094A
Application number: US473004A
Authority: US
Inventors: Shimer William Robert; James A Kinney; Frank O Kichline
Original assignee: Bethlehem Steel Corp
Current assignee: Bethlehem Steel Corp
Priority date: 1930-08-04
Filing date: 1930-08-04
Publication date: 1935-05-28
Anticipated expiration: 1952-05-28

Description

May 28, 1935 w. R. SHIMER ET AL METAL ARTICLE AND METHOD OF PREPAfiING SAME 3 Sheets-Sheet 1 Original Filed Aug. 4, 1930 ay 5- w. R. SHIMER ET AL. 2,003,094

METAL ARTICLE AND ME'fHOD OF PREPARING SAME Original Filed Aug. 4, 1930 s Sheets-Sheet 2 y 1935 w. R. SHIMER ETAL 2,003,094

METAL ARTICLE AND METHOD OF PREPARING SAME Original Filed Aug. 4, 1930 3 Sheets-Sheet 3 Patented -May 28, 1935 EQUE'IE'AL TECILE IVIETH OD 6F PRE- v v PABDTG SAME William Robert Shimer, Bethlehem, and James A.

ey and Frank 0.

Kichline, Lebanon, Pal,

assignors to Bethlehem Steel Company, a corporation oil Pennsylv Application August 4, 1930, Serial No. 473,004

Renewed October 27, 1934 5 Hart Our invention relates to sucker rods and similar articles and methods of preparing same. It also relates to corrosion resisting articles and methods for. preparing them. An important purpose is to obtain sucker rods or similar articles which shall have mechanical properties superior, to those of the ordinary sucker rod because of subjection to a particularheat treatment. Another object is a sucker rod or other article which shall be relatively incorrodible' in' service.

Our invention comprises a sucker rod having a normalized structure through the greater portion of its length and having a microstructure in the pin ends resultingv from a rapid cooling through the critical range, such metal structure of the pin end merging gradually into the nor.- malized structure of the remainder of the rod. Furthermore, our invention comprises articles, whether sucker rods or other articles, having a surface highly resistant to corrosion producing conditions;

a In presenting our invention we'shall set forth a specific example of its application but of .course it is to be understood that this example is merely illustrative and is not intended to be limiting to the protection which is sought.

In setting forth the invention we shall first briefly state the steps of an illustrative process and the cheats produced in a sucker rod and then later we shall set forth somewhat more fully the operation when employing particular equipment.

First, setting forth an outline of the process: A round bar of diameter, for example, is rolled in the regular way from steel of the fol lowing analysis: Carbon .25 to .80, manganese .50 to .80, nickel .40 to 1.00, and chromium .20 to 55. This is prepared in the desired lengths, say, 25 or 30 feet, for instance, the ends heated in the furnace to a temperature between 2000 and 2250 F. and then subjected to a series of upsetting or forging operations to form a pin end and wrench square. Next the bar is placed in a furnace and is uniformly heated throughout. itslength to a temperature above the critical range, say from 1550 to 1650" F. This may well take about fortyfive minutes. The bar is then removed from the furnace and gripped at its two ends, at the wrench squares, in gripping mechanism, which will later be described. The bar is then placed under ten- 50- sion by exercising a pull on one end against a resistance applied to the other end. The pulling 1 force is suddenly applied so that the condition of tension is initiated with a snap,'thereby effecting a straightening of the rod. At about the 55 same time of placing the rod under tension a cooling fluid is applied to the region at each end which includes the wrench square and the pin end. This application of cooling fluid is continued until these'resions of the sucker rod have been rapidly cooled through the critical range. The 5 I streams of ,fluid are discontinued, however, before the greater part of the metal in the remaining regions of the rod has cooled through the critical, range. The residual heat in the remaining portion of the rod is utilized to eilect a draw" of the 10 quenched regions. Tension is maintained, in the manner indicated, on the rod until the entire rod passes through the critical range. I The rods are now released from the gripping mechanism and allowed to cool upon a cooling table until the temperature has dropped to a temperature of from 600 to 700 F.- While at this temperature the rod is immersed in a bath of coke oven tar and then ture is uniform throughout the greater portion 5 Q of the rod length merging gradually toward the ends into the structure produced by the quenching-operation. There is no sharp line or zone of demarcation between the quenched portions and those portions which were normalized in the 30 air. The pin ends, and those portions adjoin- .ing the pin ends, where failure frequentlyoccurs,

are uniform in structure and much more resistant to failure than with ordinary rods.

The manner in which the rod is straightened and the maintaining of tension on the rod during the cooling through the critical range avoids the use of any of the ordinary straightening operations which might introduce defects or weaknesses in rod structure. 7

The-treatment with tar in some way changes the condition of the surface of the metal so as to resist corrosion. Apparently, it is not merely due to the protection afforded by the coating of tar baked on the surface, as evenbeneath the coating the rod surface is resistant to corrosive influences. Y

Having briefly outlined the process and the eflects of such process, we shall now proceed to a more detailed statement of the invention with reference to the apparatus. empl yed, Accordlngly, referring to the drawings:

Fig. L is a plan view of the equipment used; Fig. 2 is an end viewlooking in the direction of the arrows 2-2 of 8. 1; 5

Fig.3 is a'detail longitudinal view of the gripping and quenching mechanism;

in position upon the wrench square l2 at each end of the rod, the pressure of spring 4| serving Fig. 4 is a cross section of the same mechanism to efiect a gripping engagement of fingers 33 taken on the line 4-4 of Fig. 3 and upon the rod. Air is admitted to cylinder 26 Fig. 5 is a detail view of the quenching apand cross head 25 is carried suddenly to theright, paratus; as viewed in Figs. 1 and 3, jerking the rod in the To facilitate an easy understanding of the insame direction and elevating the weight 3|. This vention, it may be well to first describe the jerking action is very important as it serves very straightening and tensioning and quenching eifectively to eliminate any kinks or other condimechanism, 7 tions tending to prevent straightness in the rod. Device 22 is adapted to grip one end of sucker At the same time the rod is placed under a subrod l0 and device 23 the'other end. Device 22 stantial tension. For a rod of cross section such fingers 33. These arms'are provided at an in:

' shank proper of the rod and collar between is connected by means of chain 24 head 25 mounted on piston 26' of air cylinder 26. composition and with the particular tempera- Device 23 is connected by means of chain 21 and tures involved, about 1000 lbs. has been found suitswivel 21' to cross head 28 to which is attached able for weight 3|. cable 29 passing over pulley 30 and connected The placing of the apparatus and rod under to weight'3l. tension as "just outlined, serves to actuate the Devices 22 and 23 are essentially the same in toggles containing links 33 to produce an eflecstructure;-therefore a description of one of them tive' gripping of fingers 33 upon the ends of the will'sufilce for both. Arms 32 have rod gripping rod. The motion of cross head 25 serves to operate erm d at region with lugs 34 which contain contactor 5| which closes the circuit through openings 35 whereby the arms may be pivotally solenoid 5| and thereby serves to open air valve mounted in opposing relationship on pin 36, 52 to admit air to manifold 46 and thus to prowhich latter is mounted in the inwardly projectduce a flow of air through openings 49 of nozzle ing lugs. 31 of supporting body 38. Pivoted to pipes 48 to effect a'rapid cooling of the end regions the outer ends of arms 32 are links 39, which of the sucker rods including pin end l2, wrench latterare pivotally oonnee ed'to olevis T square l3 and collar l4. The air flow continues clevis 40 of device 22 is attached one end of chain until timer mechanism 53 in the same circuit 24 and to a correspondingclevis of device 23 is opens the circuit through solenoid thereby causve l d an end f chain 21. By means of ing valve 52 to close. The time of the quenching with cross as in the present example and of the particular a 13113581011 Spring Placed between a 3 and operation will vary somewhat but should be sufilheld in position by rod r s 32 normally tend cient to permit practically the entire mass of the to effect 8 ppi g action onfthe rod by pp end regions which are receiving the flow of air fingers 33. to cool below the critical range. Following the S pp r ng bodies 38, which supp rt devices uenching operation the principal mass of the 22 nd are provided wi h ir ar an 1' rod is still above the critical range and the tires Which r t pon Smooth Plates ,AW h residual heat in the rod serves to effect a draw 45 of bodies. are provided with circular holes of th h d tal f the ends.

ou h which pass no e 43 0f the end q Tension is maintained on the rod until the 8 mechanismentire mass thereof has passed through the Eaoh o the quenching devices Comprises 8 critical-range. When the rod has cooled below manifold 46 which is connected with a source th itic l range the gripping mechanisms are .of compressed air by means of pipe 41. released from the ends of the rod which is allowed nected with manifold 46 are nozzle Pipes 43 Which to cool to a somewhat lower temperature on are adapted to pass through the holes in web 45. table 2|; Pipes 43 are Provided i opehihgsi disposed The rod is not completely cooled on table 2| i p x ty to the end regions 1 e Sucker d but while still at an elevated temperature, say at 3. whereby air may be streamed upon wrench square temperature or from 600 to 700 F., the rod is .l3 and pin ends 12 of the sucker rod. moved therefrom into dipping rack 54 wherein Now pro e i to a'descrirtion of the the rod is dipped into a bath of tar as and then pl pr The sucker rod h v pin end raised therefrom'while still at an elevated tem- Wrench Square d with the thickened perature to permit, the tar to bum on". The portion l3 between the wrench square and therodjs t discharged t stand 55,

, Following the treatment just outlined the pin the Wr nch q re 811d the P end ll, is ro ends are machine turned and threaded. from the stock stand 15 into sins trough Sucker rods thus treated have certain char- This trough is mount d up 2 5 adapted acteristics which especially fit them for. the parto r p n kw ys The trough mved ticular type of environment in which sucker rods into P i pp grooves of heating IIII- are used. The quenched end and normalized rod nace l8 and th r p she from the in structures, merging gradually into each other, t ugh into the furnace. 1 Here the rod i h t give to the rods just the qualities which enable a Period 01 about y-fi minutes to v them most effectively to resist failures in service.

i a temp a 0! from say 5 0 to 6 The treatment with tar produces a surface which t tially un rm fr m end to end of the is very resistant to corrosion under conditions D a g trough mounted upon t s where the life of the ordinary rods is frequently 20' and rolling upon traokwfly is moved into seriously curtailed on account of corrosive inposition opposite the rod in furnace 13 and the flugncs,

rod drawn into the trough- Th trough is then Having thus described our invention what we moved to table 2l.-: claim and desire to secure by Letters Patent is: Devices 22 and 23 are now brought intoposition 1, In process 01 the class described, the steps at the ends ofthe r d, an ar 32 are p s of upsetting the end of a rod, heating the entire litogether ageinst the c n f pr 4| to p rod above the critical range, subjecting such rod th nn el en an h e are placed to sufllcient tension to straighten, qucncm tne end, drawing such the residual heat rod to cool in the quenched end by means of in the rod and allowing the air.

malized structure.

3. In a process for treating articles or the class described, the steps 01' upsetting the ends of the rod, heating the entire rod above the critical range, applying sudden tension to straighten the rod, maintaining said rod under tension, quenching the ends 01' said rod, drawing such quenched ends by means of the residual heat in the rod, and allowing the rod to cool in air through the 3 critical range to produce a normalized structure in the rod while maintaining tension thereon.

4. A sucker'rod of steel con carbon between .25% and .80%, nickel between .40% and 1.00% andchromium between 20% and .60%. having a normalizedstructure throughout the greater portion of its length, and ving a structure in its pin ends resulting from quenching and drawing, the normalized and quenched and drawn metal structures m rging rad ally into each 4 other.

5. A sucker rod 7 tween 25% and .80%, nickel between 40% and 1.00% and chromium between 20% and .60%, having a normalized structure throughout at least the greater portion oi its length.

WILLIAM ROBERT SHIMER. JAMES A. KINNEY. FRANK O..KICHLINE.

of swimming when bei Patent No. 2,003,094.

7 CERTIFICATE OF CORRECTION.

May' 28, 1935 WILLIAM AROBERT SHIMER. ET. AL. 0

I t' is hereby certified that error apoeare in the above numbered patent requiring correction as follow Bryan' M. Better (Sezil) Acting Commissioner of Patents.