US3570455A

US3570455A - Adjustable coating bath guide

Info

Publication number: US3570455A
Application number: US823093A
Authority: US
Inventors: John Neil Laidman; Laurence B Caldwell
Original assignee: Bethlehem Steel Corp
Current assignee: Bethlehem Steel Corp
Priority date: 1969-05-08
Filing date: 1969-05-08
Publication date: 1971-03-16
Anticipated expiration: 1988-03-16

Abstract

Adjustable apparatus to be partially immersed in a container holding a molten metal bath for guiding metallic members to be coated. The apparatus includes means to adjust its width to accommodate members which are passed through the bath in runs or groups having different widths or cross sections.

Description

I United States Patent 11113,570,455

[72] Inventors John Neil Laidman [5 6] References Cited Coopersburg; UNITED STATES PATENTS [21] A l N a??? Caldwen, Bethlehem 545,430 8/1895 Lewis l18/428X [22] f M 1969 752,341 2/1904 Hopkins etal.... 193/38 [45] gf g: 1971 1,736,846 11/1929 Cole etal 134/s3x 2,324,401 7/1943 Kimball 53/75 1 Assgnee Behlehem 2,559,463 7/1951 Rasmussen... 11s/30x 3,446,326 5/1969 Sandefur 193/38 54 ADJUSTABLE COATING BATH GUIDE Primary Emmim-MfmiS KaP1an 3 Claims, 3 Drawing Figs Attorney-Joseph J. O Keefe [52] U.S. Cl 118/428, M

193/38 ABSTRACT: Adjustable apparatus to be partially immersed in [51] Int. Cl 1305c 3/02 a container holding a molten metal bath for guiding metallic [50] Field of Search 118/428, members to be coated. The apparatus includes means to ad 30, 423; 134/83, 125; 193/38, 25,25 (X), 25 (IE); 214/1 (P); 95/(Inquired); 117/113-l15, (Inquired) just its Width to accommodate members which are passed 1 through the bath in runs or groups having different Widths or cross sections.

Patented March 16, 1971 /////////////////////l KZ//////////////////// v INVENTORS Jo/m Mei/ La/aman laurencc B. Caldwel/ ADJUSTABLE COATING BATH GUIDE BACKGROUND OF THE INVENTION This invention relates to apparatus for applying a protective coating to elongated structural steel members and, more particularly, to an apparatus that guides elongated structural steel members in a semicontinuous manner through a bath of molten zinc.

In a typical batch process the uncoated members are prefluxed, placed in a frame and lowered in a molten zinc bath and remain immersed for a predetermined period of time to permit application of a sufficient amount of zinc. Thereafter the frame is removed from the bath, lowered onto the shop floor and the galvanized members are removed,

Shops wherein structural members are galvanized generally handle a variety of products, e.g., beams, channels, guard rail and angles, which come in a variety of widths and cross sections. Due to this varied product mix the members heretofore had to be galvanized by a batch process asby loading the individual members onto a frame, immersing the frame into a zinc bath and then unloading the members from the frame. While historically a batch process is the one that has been practiced, several problems associated with this process have become more objectionable in recent years.

One of the objectionable features of a batch process is the slow rate of production. Today efficiency is paramount. Foreign competition makes it necessary to reduce costs, consequently a semicontinuous method isdesirable.

In the batch process each time a frame of uncoated material, which is prefluxed with-zinc ammonium chloride, is immersed in the molten zinc bath, flux fumes are emitted. This fuming pollutes the air, presents an undesirable work environment and also accelerates deterioration of equipment and property.

In addition the immersion of the frame containing the steel members into the molten zinc bath substantially lowers the bath temperature. After a period of operation the bath temperature decreases to a level whereby proper galvanizing can no longer beconducted. Production must cease, increasing costs, in order to elevate the bath temperature back to the proper level.

SUMMARY OF THE INVENTION One of the objects of this invention is to provide an adjustable guide which permits several orders of elongated structural members, having different widths, to be passed through a mol ten zinc bath one at a time with members of the same width successively following one another through the bath until all members of that width are coated and then adjusting the guide width to accommodate a subsequent run of members of a different width.

A further object of this invention is to provide an apparatus which permits galvanizing groups of elongated structural members of varying widths in a semicontinuous manner at a reduced cost.

Still a further object of this invention is to provide an apparatus for galvanizing structural members of a variety of widths in a semicontinuous manner whereby flux fuming is materially reduced.

The objects of this invention are achieved by passing structural members one at a time through a guide which is partially immersed in a molten zinc bath. Provisions are made to adjust the guide width to accommodate a variety of widths and cross sections.

These and other objects will be apparent from the disclosure which follows.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a side view of a galvanizing pot, partially in section, containing a molten metal bath in which is immersed the apparatus of this invention.

FIG. 2 is an enlarged section of the apparatus of this invention taken along line 2-2 of FIG. ll.

FIG. 3 is an isometric view of a portion of the apparatus of this invention showing in detail the adjustable feature of the guide.

DESCRIPTION OF THE PREFERRED EMBODIMENT 11 of galvanizing pot 10 through which pass elongated structural members such as beam 15 that are to be coated with molten metal of bath 13. Guide 14 has lifting hooks 16 which may be engaged by an overhead crane (not shown), a downwardly sloping entrance portion 17, a horizontal portion 18, substantially immersed in bath l3, and upwardly sloping discharge portion 19.

As shown in FIGS. 2 and 3 guide M consists of side mem bers 20 and 20' which are connected along their bottom edges by means of adjusting member 22 as hereinafter more fully described. Intermediate the top and bottom of side members 20 and 20' are deflecting

members

21 and 21. For simplicity it is preferred that structural channels be used for

side members

20 and 20.

Adjusting member 22 consists of the following elements: tie

plate 23, retaining member 24 fastened to the bottom of vertical side member 20' and adapted to receive removable holding member 25. End A of tie plate 23 is permanently fastened to the bottom portion of vertical member 20. End 8 of tie plate 23 contains slot 26 adapted to slidably receive retaining member 24. When retaining member 24 is slidably positioned to the desired location in slot 26 holding member 25 is inserted between the bottom surface 27 of the tie plate and the lower inside surface 28 of the retaining member thereby preventing further movement of tie plate 23 and establishing the spaced relationship between the vertical side members.

Apparatus of the present invention would be used in the following manner. Prior to placing the guide into the molten coating bath the distance between channels 20 and 20' is established. This distance is controlled by the width of the workpiece. Depending upon the spread required between the channels, channel 20' is moved toward or away from channel 20, retaining member 24 slidably moving laterally within slot 26. Forcibly inserting holding member 25, a triangular-shaped wedge through retaining member 24 maintains the established spaced relationship between the channels. The guide is now ready for placement in the molten coating bath.

An overhead crane (not shown), equipped with chains (not shown), is, connected to lifting hooks 16. The guide is now transported and placed into zinc pot l0. Entrance portion 17 and discharge portion 19 are supported by vertical sidewalls ll. Horizontal portion 18 is substantially immersed in bath 13.

A prefluxed metallic workpiece 15, an elongated highway guardrail member, as shown in cross section in FIG. 2, is placed into the guide at entry end 17. Urging means (not shown) is connected to the workpiece. The workpiece is transported through the guide and rides on the bottom flange of channels 20 and 20' at a predetermined speed and emerges at discharge end 19.

As the rear of this section to be galvanized approaches entrance end 17 a second member is connected to it so that one structural member after another is pulled through the guide by the member before it. This procedure is followed until all members of that size are pulled through the bath.

To prevent workpiece 15 from twisting or floating in the coating bath as it passes through the guide, deflecting means 21 and 21' are fastened to the web sections of channels 20 and 20'.

The invention as described above permits members to be individually galvanized and passed through a molten metal bath more efiiciently than was possible heretofore. The problem of maintaining a uniform coating bath temperature which caused production delays has been practically eliminated. The

problem of excessive fuming that was associated with the batch process has been materially reduced, thereby reducing air pollution.

It will be understood that modifications and variations may be efiected without departing from the scope of the novel concepts of the present invention.

We claim:

1. In an apparatus for coating elongated metallic workpieces in a bath wherein said pieces are conveyed through elongated guide means at least partially submerged in said coating bath, said guide means comprising:

a. a pair of side members comprising:

i. a downwardly sloping entrance portion,

ii. a central portion disposed in a plane parallel to the coating bath, and

iii. an upwardly sloping exit portion; and

b. adjusting means to connect said side members at varying spaced relationships from each other and comprising:

i. a tie bar with an elongated opening adjacent at least one end; I

ii. securing means mounted on said guide means and adapted to pass through said elongated opening in said tie bar; and

iii. means adapted to engage said securing means and said tie bar to prevent movement of said tie bar.

2. A pair of side members as recited in claim 1 each said side member comprising a channel wherein said channel web sections are parallel and their flange sections are facing each other. i

3. Connecting means as recited in claim 1 wherein:

a. the securing means comprises a U-shaped member fastened to a flange section of the side member; and

b. means (iii) comprises a triangular-shaped wedge member adapted to be forcibly inserted between said U-shaped member and said tie bar.

Claims

1. In an apparatus for coating elongated metallic workpieces in a bath wherein said pieces are conveyed through elongated guide means at least partially submerged in said coating bath, said guide means comprising: a. a pair of side members comprising: i. a downwardly sloping entrance portion, ii. a central portion disposed in a plane parallel to the coating bath, and iii. an upwardly sloping exit portion; and b. adjusting means to connect said side members at varying spaced relationships from each other and comprising: i. a tie bar with an elongated opening adjacent at least one end; ii. securing means mounted on said guide means and adapted to pass through said elongated opening in said tie bar; and iii. means adapted to engage said securing means and said tie bar to prevent movement of said tie bar.

2. A pair of side members as recited in claim 1 each said side member comprising a channel wherein said channel web sections are parallel and their flange sections are facing each other.

3. Connecting means as recited in claim 1 wherein: a. the securing means comprises a U-shaped member fastened to a flange section of the side member; and b. means (iii) comprises a triangular-shaped wedge member adapted to be forcibly inserted between said U-shaped member and said tie bar.