Method for making a boom

• US 4,159,796 A
• Filed: 06/23/1977
• Issued: 07/03/1979
• Est. Priority Date: 08/09/1976
• Status: Expired due to Term

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Americas Company (Caterpillar Incorporated)
• Inventors: Braithwaite, Arthur B. M.
• Primary Examiner(s): Lanham, C. W.
• Assistant Examiner(s): Ramsey, K. J.
• Application Number:
  US05/809,571
• Time in Patent Office: 740 Days
• Field of Search: 212/114, 212/17, 212/58 A, 212/58 R, 52/726, 52/730, 52/116, 52/731, 214/86 A, 29/155 R, 29/155 C, 228/173 C, 228/151, 228/152, 228/178, 228/182
• US Class Current: 228/151
• CPC Class Codes: E02F 3/32 working downwardly and towards the machine, e.g. with backhoes
• CPC Class Codes: E02F 3/38 Cantilever beams , i.e. booms;, e.g. manufacturing processes, forms, geometry or materials used for booms for booms with cable suspension arrangements E02F9/14 takes precedence; Dipper-arms , e.g. manufacturing processes, forms, geometry or materials used for dipper-arms; Bucket-arms E02F3/34 takes precedence

Abstract

A boom is made by joining two tubular members to a cast iron elbow section. The tubular members are made from plate formed into tubes with a longitudinally welded seam. The tube seams are located below a horizontal axis of the respective tube members and circumferentially between the horizontal and vertical axes thereof to dispose the weld seam on a lower side of the boom. Pivotal boom connection means are further welded to each free end of the boom and to the elbow section.

Claims

1. A method of making a boom comprising the steps of

cutting first and second plates;

rolling said plates into first and second tubular members, each having a circular cross section and abutting edges extending longitudinally thereof;

welding said abutting edges together by forming a longitudinally extending weld seam which is located at a position below a horizontal axis of a respective one of said tubular members and circumferentially between the horizontal axis and a vertical axis of said respective one of said tubular members, when such tubular member is viewed in cross section, whereby said weld seam is disposed on a lower side of said boom;

selecting elbow means having a circular cross section on each end thereof equal to the cross section of one end of each of said tubular members; and

welding said one end of each of said tubular members to an end of said elbow.

2. The method of claim 1 further comprising the step of forming said elbow means by casting.

3. The method of claim 2 further comprising the step of securing pivotal mounting means to each free end of said boom and to said elbow means.

4. The method of claim 1 further comprising the step of shaping each of said tubular members to taper from said one end thereof at said elbow to the other end thereof.