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New Equipment for Testing the Fatigue Strength of Riveted and Welded Joints

Description: "The mechanical and electrical construction of a new experimental instrument for fatigue testing riveted and welded joints is described. This experimental device has the advantage of being able to stress, even with comparatively low magnetic exciter force, structural components in alternate bending by resonance vibrations up to incipient fatigue failure (p .1)".
Date: July 1940
Creator: Müller, W
Partner: UNT Libraries Government Documents Department

Special Welding Techniques : Final Summary Report

Description: From foreword: This is the final report on Special Welding Techniques. The work of the third and final year is discussed in detail, and the accomplishments of the first two years are summarized.
Date: January 1957
Creator: Mueller, John; Maxwell, William & Siltanen, James
Partner: UNT Libraries Government Documents Department

The Effect of Surface Irregularities on Wing Drag. II - Lap Joints, 2, Lap Joints

Description: Tests have been made in the NACA 8-foot high-speed wind tunnel of the drag caused by four types of lap joint. The tests were made on an airfoil of NACA 23012 section and 5-foot chord and covered in a range of speeds from 80 to 500 miles per hour and lift coefficients from 0 to 0.30. The increases in profile drag caused by representative arrangements of laps varied from 4 to 9%. When there were protruding rivet heads on the surface, the addition of laps increased the drag only slightly. Laps on the forward part of a wing increased the drag considerably more than those farther back.
Date: February 1938
Creator: Hood, Manley J.
Partner: UNT Libraries Government Documents Department

Analytical and experimental investigation of bolted joints

Description: From Introduction: "The present paper contains the development of a recurrence formula for the bolt loads for the simplified case of a symmetrical butt joint with bolts spaced evenly in line with the applied load. The method presented herein is based on the fundamental relationship which was developed in reference 1 between the loads on any two successive bolts. The present paper also gives the results of an experimental investigation conducted to substantiate further the adequacy of the elastic theory as well as to yield additional data on the critical bolt load and the behavior of long joints in the plastic range and at the ultimate load."
Date: October 1947
Creator: Rosenfeld, Samuel J.
Partner: UNT Libraries Government Documents Department

The effect of the type of specimen on the shear strengths of driven rivets

Description: Report presenting tests of various types of riveted joint composed of 24S-T sheet and 1/8-inch A17S-T rivets in order to determine the effects of specimen type on shear strengths. The results indicated that there was only a slight variation in shear strength with considerable variation in the types of specimen.
Date: November 1943
Creator: Sharp, W. H.
Partner: UNT Libraries Government Documents Department

Comparison of Static Strengths of Machine Countersunk Riveted Joints in 24S-T, X75S-T, and Alclad 75S-T Sheet

Description: Note presenting static tests made on machine-countersunk riveted joints in 24S-T, X75S-T, and Alclad 75S-T sheet using A17S-T and 24S-T rivets. In order to intensify the cutting action of the rivets, all specimens were made with the depth of countersink just equal to the thickness of the sheet.
Date: May 1946
Creator: Hartmann, E. C. & Zamboky, A. N.
Partner: UNT Libraries Government Documents Department

Design of Tools for Press-Countersinking or Dimpling 0.040-Inch-Thick 24S-T Sheet

Description: "A set of dimpling tools was designed for 0.040-inch 24S-T sheet and flush-type rivets 1/8 inch in diameter with 100 degree countersunk heads. The dimples produced under different conditions of pressure, sheet thickness, and drill diameter are presented as cross-sectional photographs magnified 20 times. The most satisfactory values for the dimpling tools were found to be: maximum punch diameter, 0.231 inch; maximum die diameter, 0.223 inch; maximum mandrel diameter, 0.128 inch; dimple angle, 100 degree; punch springback angle, 1 1/2 degree; and die springback angle, 2 degree" (p. 1).
Date: August 1942
Creator: Templin, R. L. & Fogwell, J. W.
Partner: UNT Libraries Government Documents Department

The Shear of Aluminum Alloy Driven Rivets as Affected by Increasing D/T Ratios

Description: "A decrease in shear strengths for increasing D/t ratios was shown in a previous investigation of protruding-head aluminum alloy rivets in double shear conducted at Aluminum Research Laboratories in 1942. Since single shear joints are more common than double shear joints, it was desirable to extend the investigation to single shear joints. This reports describes the results of this investigation of single shear joints and also includes the results of the previous investigation on double shear joints" (p. 1).
Date: July 1944
Creator: Hartman, E. C. & Wescoat, C.
Partner: UNT Libraries Government Documents Department

Fatigue Tests of Riveted Joints : Progress Report of Tests of 17S-T and 53S-T Joints

Description: Report presenting the fatigue data obtained at the Aluminum Research Laboratories from tests of various types of 17S-T and 53S-T specimens. The specimens were large enough to represent actual service conditions, but the repetition of loading was more rapid than would occur in ordinary service.
Date: September 1944
Creator: Hartmann, E. C.; Lyst, J. O. & Andrews, H. J.
Partner: UNT Libraries Government Documents Department

High Pressure Low Resistance Joint

Description: The following report describes the usage of tin-foil to obtain a mechanical joint of low electrical resistance while providing a seal to hold water at a pressure of 300 psi.
Date: March 28, 1955
Creator: Peters, Ralph
Partner: UNT Libraries Government Documents Department

Investigation of surface irregularities on an NACA 63(420)-416, a=1.0 airfoil section for the Glenn L. Martin Company design 195

Description: Report presenting the results of an investigation made in the two-dimensional low-turbulence pressure tunnel of surface irregularities on a low-drag airfoil section. The primary objective was to determine the effects of riveted and piano-hinge-type skin joints and of an aileron slot of the drag characteristics. Any type of surface irregularities at the front spar were found to cause substantial increase in drag.
Date: October 1943
Creator: Braslow, Albert L.
Partner: UNT Libraries Government Documents Department

Summary of Results of Tests Made by Aluminum Research Laboratories of Spot-Welded Joints and Structural Elements

Description: "Available information concerning spot welding as a means of joining aluminum-alloy parts has been summarized and comparisons have been made of the relative merits of spot-welded and riveted aluminum-alloy structural elements. The results indicated that spot welding was as satisfactory as riveting insofar as resistance to static loads is concerned. Spot welds showed slightly lower resistance to impact loads but definitely lower resistance to repeated loads than rivets" (p. 1).
Date: November 1942
Creator: Hartmann, E. C. & Stickley, G. W.
Partner: UNT Libraries Government Documents Department

Creep and Creep-Rupture Characteristics of Some Riveted and Spot-Welded Lap Joints of Aircraft Materials

Description: Note presenting a description of equipment and test technique used in the creep testing of lap joints. Riveted aluminum-alloy joints fabricated from 75S-T6 and 24S-T3 sheet with 24S and 24S-T31 rivets were tested at 300, 400, and 500 degrees Fahrenheit. The test results showed that the creep of the riveted joints is considerably greater than the creep of the unriveted sheet although not so large that the creep of the sheet is negligible compared with that of the joints.
Date: June 1955
Creator: Mordfin, Leonard
Partner: UNT Libraries Government Documents Department

Results of Shear Fatigue Tests of Joints With 3/16-Inch-Diameter 24S-T31 Rivets in 0.064-Inch-Thick Alclad Sheet

Description: Note presenting shear fatigue tests of joints with rivets in Alclad sheet of several high-strength aluminum alloys. The results showed that the design of the joint gives a wider range of fatigue strengths than does the choice of material from the group studied. No one sheet alloy showed superiority over the others.
Date: February 1950
Creator: Holt, Marshall
Partner: UNT Libraries Government Documents Department

Guideline for bolted joint design and analysis : version 1.0.

Description: This document provides general guidance for the design and analysis of bolted joint connections. An overview of the current methods used to analyze bolted joint connections is given. Several methods for the design and analysis of bolted joint connections are presented. Guidance is provided for general bolted joint design, computation of preload uncertainty and preload loss, and the calculation of the bolted joint factor of safety. Axial loads, shear loads, thermal loads, and thread tear out are used in factor of safety calculations. Additionally, limited guidance is provided for fatigue considerations. An overview of an associated Mathcad{copyright} Worksheet containing all bolted joint design formulae presented is also provided.
Date: January 1, 2008
Creator: Brown, Kevin H.; Morrow, Charles W.; Durbin, Samuel & Baca, Allen
Partner: UNT Libraries Government Documents Department

Passive legged, multi-segmented, robotic vehicle.

Description: The Passive-legged, Multi-segmented, Robotic Vehicle concept is a simple legged vehicle that is modular and scaleable, and can be sized to fit through confined areas that are slightly larger than the size of the vehicle. A specific goal of this project was to be able to fit through the opening in the fabric of a chain link fence. This terrain agile robotic platform will be composed of multiple segments that are each equipped with appendages (legs) that resemble oars extending from a boat. Motion is achieved by pushing with these legs that can also flex to fold next to the body when passing through a constricted area. Each segment is attached to another segment using an actuated joint. This joint represents the only actuation required for mobility. The major feature of this type of mobility is that the terrain agility advantage of legs can be attained without the complexity of the multiple-actuation normally required for the many joints of an active leg. The minimum number of segments is two, but some concepts require three or more segments. This report discusses several concepts for achieving this type of mobility, their design, and the results obtained for each.
Date: November 1, 2003
Creator: Hayward, David R.
Partner: UNT Libraries Government Documents Department

Report on the SNL/AWE/NSF international workshop on joint mechanics, Dartington, United Kingdom, 27<U+2013>29 April 2009.

Description: The SNL/AWE joint mechanics workshop, held in Dartington Hall, Totnes, Devon, UK 26-29 April 2009 was a follow up to another international joints workshop held in Arlington, Virginia, in October 2006. The preceding workshop focused on identifying what length scales and interactions would be necessary to provide a scientific basis for analyzing and understanding joint mechanics from the atomistic scale on upward. In contrast, the workshop discussed in this report, focused much more on identification and development of methods at longer length scales that can have a nearer term impact on engineering analysis, design, and prediction of the dynamics of jointed structures. Also, the 2009 meeting employed less technical presentation and more break out sessions for developing focused strategies than was the case with the early workshop. Several 'challenges' were identified and assignments were made to teams to develop approaches to address those challenges.
Date: August 1, 2010
Creator: Ewins, David J. (University of Bristol, UK); Bergman, Lawrence A. (University of Illinois, Urbana, IL) & Segalman, Daniel Joseph
Partner: UNT Libraries Government Documents Department

CONTACT-RESISTANCE SYMPOSIUM, BENDIX AVIATION CORPORATION, KANSAS CITY DIVISION, SANDIA CORPORATION, JUNE 14, 1957, ALBUQUERQUE, NEW MEXICO

Description: The objectives of the conference were to accomplish an interchange of information and study the determination of contact resistance. The effect of contacts on AEC production problems is discussed. Otber discussions are presented one applications of contact devices, present testing criteria, materials and process variables, process controls, and future development plans. (T.R.H.
Date: May 1, 1958
Creator: none,
Partner: UNT Libraries Government Documents Department

Mechanical properties of flush-riveted joints

Description: Report discusses the strength of several types of flush-riveted joints, including single-shearing, double-shearing, and tensile specimens. The stress at failure, type of failure, and d/t ratio are provided. Dimpled joints were found to be the strongest, but their strength was heavily influenced by the details of their construction.
Date: January 1940
Creator: Bruggeman, Wm. C. & Roop, Frederick C.
Partner: UNT Libraries Government Documents Department

Multidimensional Analysis of Quenching: Comparison of Inverse Techniques

Description: Understanding the surface heat transfer during quenching can be beneficial. Analysis to estimate the surface heat transfer from internal temperature measurements is referred to as the inverse heat conduction problem (IHCP). Function specification and gradient adjoint methods, which use a gradient search method coupled with an adjoint operator, are widely u led methods to solve the IHCP. In this paper the two methods are presented for the multidimensional case. The focus is not a rigorous comparison of numerical results. Instead after formulating the multidimensional solutions, issues associated with the numerical implementation and practical application of the methods are discussed. In addition, an experiment that measured the surface heat flux and temperatures for a transient experimental case is analyzed. Transient temperatures are used to estimate the surface heat flux, which is compared to the measured values. The estimated surface fluxes are comparable for the two methods.
Date: November 18, 1998
Creator: Dowding, K.J.
Partner: UNT Libraries Government Documents Department

Comparative fatigue tests of riveted joints of Alclad 24S-T, Alclad 24S-T81, Alclad 24S-RT, Alclad 24S-T86 and Alclad 75S-T sheet

Description: Report discusses testing performed to determine the fatigue strength of various types of riveted and spot-welded joints in the following aluminum alloys: Alclad 24S-T, 24S-RT, 758-T, 24S-T81, and 24S-T86. Details of the experiment, tensile properties, and information about failure are provided.
Date: August 1945
Creator: Moore, R. L. & Hill, H. N.
Partner: UNT Libraries Government Documents Department