Showing papers on "Butt joint published in 1990"

In log joint and machine for forming log joint

Abstract: In a tongue and groove log joint a seal seating channel is formed in the base of the longitudinal groove and a resiliently flexible seal is seated in the seal seating channel. A slot may also be cut in the base to accommodate a reinforcing metal rod. In a butt joint in which a second log underlies the butting logs a seat is formed in the edge of the second log in alignment with the locking slots of the butt joint to receive an end of the locking pin. The seat locks the locking pin against longitudinal movement with respect to the second log. In a wall construction in which the logs of the adjoining walls are connected by an overlapping tenon joint, a first pair of elongated tubular cavities arranged one on each side of a first interface and a second pair of elongated tubular cavities arranged one on each side of a second interface. The tie members are located at each interface and are arranged with one lobe seated in one of the tubular cavities on one side of the interface and the other lobe seated in the tubular cavity on the other side of the interface.

Stress Distribution in Plane Scarf and Butt Joints

Abstract: The stress distribution in a plane scarf joint, which may have an arbitrary angle of scarf as well as arbitrary elastic parameters for its adherends and adhesive, is analyzed. The analysis is based on the two-dimensional elasticity theory in conjunction with the variational principle of complementary energy. Minimizing the energy functional leads to a specific optimization problem with two variables for the determination of the stresses. Some typical features of the stress distribution are shown by numerical examples. Criteria for uniformly distributed adhesive stresses which are of importance in practice are deduced. The butt joint is treated as a special case of scarf joints.

Joining of Si3N4 using Ag57Cu38Ti5 brazing filler metal

Abstract: Hot-pressed Si3N4 was joined using Ag57Cu38Ti5 brazing filler metal at 1103 to 1253 K for 5 min in a vacuum. The interface reactions between Si3N4 and the brazing filler metal during brazing are reported. An important event is sufficient interface reaction, characterized by the formation of a layer of TiN with an appropriate thickness at the ceramic-filler interface. The joining strength of the butt joint depends on the interface reaction, and a maximum joining strength of 490 MPa measured by the four-point-bend method is achieved for the Si3N4-Si3N4 joint brazed at 1153 K for 5 min. It is also discussed how to design the best brazing filler metal for joining ceramic to ceramic or ceramic to metal.

Method and apparatus for automatic multi-run welding

Abstract: This invention relates to a method and apparatus for automatic multi-run welding of a joint such as a square butt joint, a V-type joint, or a U-type joint, etc. This invention incorporates a sensor which moves along the joint and which scans a number of points along portions of the joint. The points scanned are used to calculate the cross-sectional area of the portions of the joint and the cross-sectional areas are then used to determine welding parameters, such as weld speed and weld rod feed, for the welding which is to be done in each of the joint portions. Thus, the joint is filled with weld material uniformly along its length despite deviations which may be inherent in the edges of the materials which are being welded.

Strength of Bell-and-Spigot Joints

Abstract: Although bell-and-spigot joints have been used successfully for many years in the construction of large-diameter water-pipe mains, questions sometimes arise concerning the efficiency of the joints under axial (longitudinal) forces. In this paper, a simple general-yielding approach is used to develop an equation that can be used to directly determine the strength of such joints. The calculated joint efficiency, which depends on the ratio of the joint eccentricity to the pipe-wall thickness, ranges from 0.41 for a zero gap to 0.24 for a gap equal to the pipe thickness. The equation is reasonable and conservative when compared to finite-element results, to the ASME code, and to test results. Also, tests show that a single full-thickness fillet weld can provide adequate strength. Such joints should be used wherever possible because they are much more economical than butt joints.

Heat bonding of butt joint of fluororesin film

Abstract: PURPOSE: To permit butt joints to be sealwelded by a method wherein the fluororesin cover film so colored as to absorb YAG laser beam is placed over the butt joint of a fluororesin film and the films are heat bonded with the YAG laser beam. CONSTITUTION: A steel plate 1 is coated with an epoxy adhesive agent 2 of two liquid mixed cold setting type and the fluororesin film 3 whose one side is treated with plasma to make its surfaces uneven in order to improve its adhesion is bonded to the adhesive coated surface of the aforesaid steel plate. The fluororesin-to-fluororesin bonding is objectionable for reasons of its surface property. As a result, a heat bonding is made to treat the seam joints. To perform this heat bonding, YAG laser is used as a heating source. Specifically, a colored cover film 5 placed over a seam joint part 4 is irradiated with the laser beam produced by a power source 12 and a YAG laser generator 11 through a beam in-coming system 10, an optical fiber cable 9 and a beam out-going system 7, whereby the cover film and lining film are heat bonded together successively. COPYRIGHT: (C)1992,JPO&Japio

Integrated Matrix Creep: Application to Lifetime Prediction of Eutectic Tin-Lead Solder Joints

Abstract: The matrix creep failure indicator developed by Shine and Fox is extended to cases when strain is multiaxial and varies with position in the structure. Analysis of a thermal fatigue test of leaded surface mount devices found in the literature illustrates application of the method. A butt joint surface mount configuration is then tested in simple mechanical loading and also analyzed using the finite element method. It is found that the matrix creep “damage integral” method gives good correlation with observed solder fatigue failures for both cases.

Method of heat sealing a battery

Abstract: A heat sealed butt joint for plastic parts such as a battery formed by at least a two step force application. The adjacent portions of the butt joint of the battery cover and case are preheated to a near liquid state causing rollover on the sides of the joint. The first step force application is of a lighter amount and is held for a predetermined time which causes the heated rollover on the sides of the battery to solidify. The second step force is of a heavier amount and is held for a predetermined time which causes the molten polymers of the heated portions of the battery cover and case to mix and bond together while the solidified rollover from the first step acts as a dam to prevent further rollover during the second step. The formed sealed battery has improved bursting strength and the process can be used for joining various other butting plastic parts to improve the tensile strength of the bond between the parts.

Influence of joint gap width on strength and fracture toughness of copper brazed steels

Abstract: The strength of brazed butt joints is commonly assessed in terms of the tensile performance of defect-free laboratory testpieces. In practice, brazed joints often contain crack-like defects which dominate the mechanical performance. The present work examines the strength and fracture toughness of copper brazed joints in steel. It is shown that the tensile strength of defect-free joints increases as the joint gap decreases and as the strength of the steel increases. Conversely, the fracture toughness is observed to decrease to a very low level as the joint gap decreases and as the strength of the steel increases. As a result, thin brazed joints are very susceptible to the presence of defects and, in practice, it is difficult to take advantage of the potential strength available. The reason for the relationship between toughness and joint gap is that toughness is determined by the extent of crack tip plasticity which, for a brazed joint, is controlled by the thickness of the braze metal.MST/1124

Effect of butt joints on the flexural stiffness of laminated timber bridges

Abstract: Prestressed and nailed laminated timber bridge decks are made from laminates which, because of their being usually shorter in length than the deck span, are butt-jointed at regular intervals. In calculating deflections of such decks, it is usual to ignore the reduction in flexural rigidity of the deck caused by the presence of the butt joint. The effect of butt joints on the flexural rigidity of the laminated deck is studied analytically, and it is shown that the deflections of a deck having such joints may be significantly larger than those of a deck without them. A simple method is presented to account conservatively for the presence of butt joints in the calculation of the deflections of a prestressed laminated timber deck. Key words: timber bridge, laminated deck, butt joint, prestressed wood deck.

Method for profiling weld line

Abstract: PURPOSE:To always accurately profile the center of groove width by correcting the output of a deflection detection magnetic sensor by the output of a step quantity detection magnetic sensor. CONSTITUTION:The magnetic sensor 16 to detect deflection of a welding torch with respect to the central position in the direction of groove width of a butt joint and the magnetic sensor 1 to detect the step quantity of the butt joint are arranged. The welding torch is moved along the groove center according to the output of the deflection detection magnetic sensor 16 and the welding torch is held at the prescribed height according to the output of the step quantity detection magnetic sensor 17. When the butt joint has a step, the output of the deflection detection magnetic sensor 16 is corrected by the output of the step quantity detection magnetic sensor 17. By this method, accurate profiling of a weld line with respect to a square groove butt joint can be performed under noncontact state and the center of groove width can be always accurately profiled.

Butt joint device for rubber sheet

Abstract: PURPOSE:To prevent thickness in a butt joint part of a rubber sheet from growing larger by installing a means for removing the cut remnant of the rubber sheet being cut. CONSTITUTION:Each edge of rubber sheets 1, 2 to be butted is cut by a cutter 12. At this time, the cut remnant A of these rubber sheets 1, 2 is held by holding parts 22a, 23a of a gripper mechanism 21 and pulled down from a cutter bearer 15 by operation of a tension cylinder 26. Afterward, the cutter 12 is retracted, and the rubber sheets are rolled on a take-up roller 3. At this winding time, only one side edge of each cut surface of the rubber sheets 1, 2 is coherently bonded, so that both cut surfaces of the rubber sheets 1, 2 come into contact with each other as a whole, coming into a state of being butted, thus these rubber sheets 1 and 2 are butt-jointed by dint of stickiness of unvulcanized rubber.

Estimation of fatigue life of adhesive joints and reliability assessment

Abstract: The fatigue test data of adhesive bonded butt, lap and tube joints under the same adhesive conditions have been collected. The fatigue lives of these joints depend on th shape and size of adhesive joints, i.e. the lap length, adherend thickness and so on , because the stress distribution of the adhesive layer varies with such shape parameters of adhesive joints. Hence, in this study the collected S-N data were tentatively standardised by the maximum stress in the adhesive layer obtained by the finite element method. Then the standardised fatigue strength was compared with that of butt joints. The results indicate that the fatigue strength of lap joints can be estimated based on that of the butt joints of the same adhesive thickness. A statistical analysis was conducted in order to evaluate the reliability of these estimated values.

Butt joint between two flat-oval ventilating-pipe lengths made of sheet metal

Abstract: Butt joint between two flat-oval ventilating-pipe lengths made of sheet metal, in which a hollow-section flange with triangular hollow section is composed of a plurality of flange portions and placed on the pipe lengths to be connected and anchored thereto. The individual hollow-section portions are fixed to one another by connecting devices before the flange frame is put on. In a preferred embodiment, the connecting devices consist of intermediate connectors which are inserted by holding parts into a respective open end of a flange-section portion and anchored therein, a central screwing part of the intermediate connector having in each case a screwing hole for the bracing of the mutually opposite flange frames.

Welding method for titanium clad steel

Abstract: PURPOSE:To improve fatigue strength of a joint by forming a recessed part on a boundary part between titanium of clad steel and carbon steel and filling inert gas thereinto and then, subjecting the butt joint of titanium to penetration welding. CONSTITUTION:Single-V grooves 5 are formed respectively on the surface of the titanium 2 side of the butt joint and the rear of the carbon steel side 3 and the recessed part 11 is provided to the boundary part. Carbon steel 13 is first welded and then, the butt joint 12 of titanium is subjected to penetration welding while inert gas being supplied to the recessed part 11 from a telltale hole 9. By this method, since titaniums and carbon steels can be subjected to butt welding mutually separately, the fatigue strength of the joint with respect to fatigue due to thermal expansion, etc., is remarkably improved.

Butt-joint type t model plastic shuttering

Abstract: Disclosed is a T-shaped plastic shuttering which is a special shuttering for the construction of reinforced concrete ribbed floor slabs. The existing T-shaped plastic shutterings can be assembled into a row of ribbed floor slabs by having two types-a standard type and a jointing type, and thus two dies are needed, while a set of die needs 300, 000 thousand RMB. The T-shaped plastic shuttering aims at using plastic shutterings produced by one type to replace original plastic shutterings produced by two types, and thus a set of die which costs about 300, 000 thousand is saved. In addition, the integral stiffness of the shuttering can be evidently enhanced.

Cushion pad of seat

Abstract: PURPOSE:To raise a posture holding property and cushioning property by consisting an insertion material of an in-mold foamable molding body of specified apparent density polyolefin resin, and molding by a hollow body combined with two or more pieces, and further, giving an adhesive treatment on the surface in contact with a pad material of the insertion material. CONSTITUTION:The high density of polyolefin resin foamable body used as an insertion material 2 is 20-100kg/cm . At than less 20kg/cm , it becomes too flexible and insufficient in a holding property due to deformation by weak forces, and at more than 100kg/cm , it becomes too rigid and gets a cushioning property and setting feelings worse. And, the insertion material is formed by a hollow body combined with two or more pieces 7a, 7b. It is preferred to select a butt joint method so that the butt joined part of the pieces are firmly joined physically. And, the integration of the hollow body is strengthened by joining the butt joint part of the pieces with an adhesive agent. In this manner, the insertion material is made a hollow body, as a result, the insertion material can absorb forces from the outside through a bending deformation, thereby improving a cushioning property.

Butt connection between two duct sections of sheet metal

Abstract: A butt joint between two air duct sections (10,12) made of sheet metal has two through screw connections (34,36) to each other to be fixed flange frame (14,14 ') with intermediate connectors (30,30'), which are in turn mounted at the ends of successive abutting duct sections. An approximately radially outer flange arms (14,14 ') and an inner flange arm (16,16') are at least partially designed as L-shaped hollow profile into which the likewise L-shaped profile of the intermediate connector is fitted.

A Stress Analysis of a Band-Adiiesive Butt Joint Subjected to a Torsional Load

Abstract: The stress distribution and the displacement are examined when an adhesive butt joint, in which two dissimilar tubular or solid shafts are bonded at the interface partially, are subjected to a torsional load. In the analysis, general representations of the stress and the displacement are given as a torsional problem. Then, the effects of the ratio of the shear modulus of an adhesive to that of the shafts, the bonded portion of band-adhesive, i.e., partially bonded and the thickness of the adhesive on the stress distribution at the interface are clarified by the numerical calculations. In the numerical calculation of the band-adhesive joint, it is seen that the shear stresses at the inner and the outer circumferences of the interface become steep so that the stresses are singular at the points.

Composite thermoplastic filament and bonding method

Abstract: The invention relates to a thermoplastic monofilament composed of two parts, in particular in the form of a helix as a tube insert, and to a production process To achieve a reduction in scrap, it is proposed that the filaments butt with their ends against one another, that the parts are covered in the region of the butt joint by a sleeve of a material of the same softening temperature and that an unreleasable bond is created by melting at least partial regions of the materials

Ti-Cu-Crろうによるチタンのろう付

Abstract: Mechanical properties of work hardened pure titanium joint brazed with Ti-Cu-Cr-Al filler metal were investigated.Test specimens were brazed with filler metal containing 29%Ti, 62.5%Cu, 6.5%Cr and 2%Al in a vacuum. Brazing temperature were 850°C, 900°C, 1, 000°C and 1, 100°C for 10sec. Tensile strength of butt joints were comparable to that of joints brazed with conventional Ti-Ni-Cu filler metal, and hardness at the joint was lower. The reaction of filler metal with base metal was modertely and damage of base metals were less. The addition of pressure to joint during brazing gave significant effect on joint strength.