115 Fatigue

S-N curve The graphical relationship between the stress 5 and the number of cycles N required to cause failure of a material in a fatigue test. This depends on the mean stress, frequency and shape of the stress cycle, the temperature and the environment, all of which should be specified. Note this applies to high cycle fatigue. High strain fatigue is strain, not stress, related and the plastic strain per cycle resulting in failure ep is inversely proportional to N1 2 for almost all engineering...

85 Balancing and dressing

To ensure safe operation and to achieve the best quality of surface on the work piece, the wheel must be balanced and dressed. Several methods of balancing are available static, dynamic and automatic balancing self-balancing. In many applications, static balancing (which is simple and cheap) is quite adequate. With static balancing the balance weights are usually incorporated in the wheel flanges. Initially, the balance weights are set opposite each other, the wheel assembly is fitted to the...

25

' For definition of A and K see Figure 3.11. (1) there is directional feeding (solidification) from that part of the casting which is most remote from the foot of riser (2) the time of action of the riser (time of solidification) is longer than the time of solidification of a hot spot and (3) the liquid alloy in the riser absorbs gas and non-metallic inclusions. (1) be easy to remove and not hinder the transfer of heat from the casting (overheating of the moulding sand) and (2) not hinder the...

10424 Speed control of induction motors

Under normal circumstances, the running speed of an induction motor will be about 94-98 of the synchronous speed, depending on the load. With the synchronous speed given by equation (10.118), it is clear that the speed may be varied either by changing the frequency of the supply current, or by changing the number of poles. 10.4.24.1 Change of supply current frequency Solid-state variable-frequency drives first began to appear in 1968. They were originally applied to the control of synchronous...

55

* Reproduced by permission of North Holland Publishing Co. * Reproduced by permission of North Holland Publishing Co. Figure 1.61 Strength-to-density ratio for several classes of high temperature materials with respect to temperature. (Reproduced by permission of Metals and Materials) Figure 1.61 Strength-to-density ratio for several classes of high temperature materials with respect to temperature. (Reproduced by permission of Metals and Materials) Figure 1.62 Three-dimensional orthogonal...

T6

* Reproduced by permission of the heirs of Dr E. A. West. i As there are variations depending on form and thickness, details must be obtained from the relevant British Standard. * Reproduced by permission of the heirs of Dr E. A. West. i As there are variations depending on form and thickness, details must be obtained from the relevant British Standard. Initial guide to selecting aluminium alloys for use at elevated temperatures'

48 Cold drawing of wire and tube

As pointed out earlier, hot processing normally produces low-strength materials and uneven dimensional properties of the product. If high-quality fabricates are required, cold processing must follow the preliminary hot method of shape acquisition. In axisymmetric components, such as wire (rod) and seamless tubing, this is achieved by cold drawing the hot-finished product through a die (or a series of dies). This treatment imparts good mechanical properties and effectively regulates dimensional...

1400910

All phases are constituents but some constituents are not necessarily phases, e.g. pearlite is a constituent but it consists of the phases cementite and ferrite in a particular arrangement. The phase diagram represents the phases present, at given temperatures, which are in equilibrium with each other. Equilibrium is attained by slow heating or cooling to allow constitutional changes to be completed. The iron-carbide phase diagram (Figure 1.12) shows the effect of...

R Goss

9.1.1 Automatic insertion of fasteners 9 3 9.1 A Load sensing in bolts 9 5 9. .(p Threaded inserts and studs for plaSliM 9 7 9.1.9 Stiff nuts 9 7 91-llJ Washers 9 7 4.1.11 Spring steel listeners 9 8 9.1.13 Self-sealing fasteners 9 8 9.1.15 List of suppliers of fasteners 9 JO 9.2 Welding, soldering and brazing 9 11 9-2.2 Soldering and brazing 9 25 9.2.3 Productivity and welding economics 9 26 9.3.2 Modern engineering adhesive* by category 9 27 9.3.3 Designing with sdhesives 9 2ft 9-3,4 Anaerobic...

Info

Figure 9.17 Classification of principal welding processes Figure 9.19 Manual metal arc welding with covered electrode Figure 9.19 Manual metal arc welding with covered electrode a.c. or d.c. is used and whether the polarity is electrode positive or negative. They will also transfer the metal against the force of gravity, so that vertical or overhead welding is possible. Electrodes Electrodes have core wire diameters of 2.4-10 mm and are 300-450 mm in length. The deposition rate of weld metal,...

7

Figure 9.18 Welding circuit for manual metal arc welding welding power source, such as an a.c. transformer or a d.c. generator (Figure 9.18). The other terminal of the power source is connected to the work piece via the earth return or the ground cable, so that when the end of the electrode is placed in contact with the work piece, electric current flows through the circuit. By withdrawing the tip of the electrode to about 3 mm from the work piece, an arc will be struck and current will...

M

Figure 9.16 Examples of welded joints Manual metal arc welding, referred to as 'shielded metal arc welding' in the USA, is the most widely used welding process and accounts for approximately 50 of all the welding carried out in the world today. With this process, welding is carried out with flux coated electrodes which are connected via an electrode holder and length of cable to one terminal of a Electrode holder Power source and controls

Q

Figure 9.14 Blind rivets, (a) Break-stem mandrel, (b) Pull-through mandrel, (c) Break-stem mandrel (open end), (d) Break-stem mandrel (closed end), (e) Threaded mandrel, (f) Drive pin. (g) Chemical expanded (open end), (h) Chemical expanded (closed end) 9.1.15 List of suppliers of fasteners Armstrong Screws and Fixings, 72 Great Barr Street, Birmingham B9 4BJ, UK Bollhoff Fastenings Ltd. Midacre, The Willenhall Estate, Willenhall WV13 2JW, UK British Industrial Fasteners Federation, Queens...

U

Figure 9.11 Various types of plastics fasteners, (a) Dart-type clip, (b) Nylon expansion nut. (c) Plastirivet. (d) Rachet rivet, (e) Plastics rivet, (f) Triploc rivet Figure 9.11 Various types of plastics fasteners, (a) Dart-type clip, (b) Nylon expansion nut. (c) Plastirivet. (d) Rachet rivet, (e) Plastics rivet, (f) Triploc rivet 120 countersunk head Head dia. 2 x shank dia. Rounded countersunk head 60 Head dia. 1.5 x shank dia.

141 Copper and its alloys

Copper is basically more expensive than iron but has important advantages for special applications, the most significant of which is conduction. The electrical conductivity of pure copper is superior on a volume basis to all metals other than silver, and on a weight (and specific cost) basis to all metals other than aluminium. The same relationships apply to its thermal conductivity. Both properties are reduced by alloying, but the conductivities of copper alloys are superior to those of...

1010

Cast blades Vacuum casting has provided an alternative manufacturing route. Problems met with in the earlier alloys included cracking due to the separation of massive carbides on solidification and the formation of cr-like intermetallic compounds. However, in one specific alloy, IN100, up to 70 y' fraction was achieved. This had the immediate effect of eliminating the need for solid solution strengthening so that a low density high creep resistance material became available. Early casts of...

1020

8.20.2 Barrel polishing finishing Barrelling is an inexpensive method of processing small to medium sized products in bulk, giving considerable savings on manual methods. Applications include cleaning small castings, deburring, and polishing prior to plating. Barrels may be rotated vertically, horizontally or obliquely. Horizontal closed barrels can also be designed to reciprocate, which is advantageous when treating recessed components. Facilities must be provided for loading and unloading the...

831 Grit size

The abrasive grains making up the wheel are accurately graded and a wheel will usually contain only one size of grit. Wheels having a coarse grit size are used for roughing operations where rapid metal removal is required and surface finish is not critical. Finer grit sizes are used for finishing operations, giving superior surface finish but with a reduction in metal removal rate. The relationship betwen the type of work and the grit size is shown in Table 8.2.

25 Survey of commercial plastics materials

As with the rubbery materials the market for plastics materials is dominated, in tonnage terms, by a small number of polymers. Today, four polymers, namely polyethylene, polypropylene, PVC and polystyrene, account for about 80 of the total market tonnage. There are additionally several hundred other materials which could be classified as plastics that are on the market. Most of these have been considered at greater depth by the writer elsewhere3 and this section can only give an outline...

911 Automatic insertion of fasteners

Depending on specific applications, most fasteners in use today can be installed automatically and, since some 80 of the total cost of fastening is on-assembly cost, a mere saving of 10 in assembly costs is more significant than a 40 saving in piece part costs. Nevertheless, 80 of manufacturers assembling products with automated or robotic screwdriving equipment claim to have difficulties with their fasteners. This is the finding of a recent research survey carried out for European Industrial...

0935

Lubrication, the range of processes materials, etc., will often call for further modifications to be made and, consequently, for the extension of the laborious and unreliable testing technique. In addition, the lack of appreciation of the fundamentals of the mechanics of metal flow and deformation in a given process very often results in the adoption of tool profiles which, although apparently working, impose unduly severe conditions. Tool profiles, so established, can become complicated and...

Vs

1940 1950 1960 1970 1980 1990 2000 Approximate year available Figure 1.50 Comparative 1000 h rupture strengths of nickel alloy gas turbine blading materials produced by a variety of techniques Figure 1.51 Increase in temperature capability for turbine-blade alloys based on creep rupture in 1000 h at 150 MPa. (Reproduced by permission of Metals and Materials) MONEL alloy 400 63.0 0.15 1.0 MONEL alloy 411) 66.0 0.2 0.8 MONEL alloy K-500 63.0 0.15 1.5 HASTELLOY alloy B Bal. 0.09 1.0 VO.3 HASTELLOY...

2l92

LM10 TB, LM12 TF, LM13 TF, L35, 2L92 5083 0, 5251 0 H4-H8, 5454 0 H2-H8, 6063 T6, 6082 T6, 7075 T6 2014 T6, 2618 T6, 3103 H8, 5083 0, 5251 0 H4-H8, 5454 0 H2-H4, 6082 T6, 7075 T6 2618 T6, 5083 0, 5251 H4-H8, 5454 0 H2-H4 2014 AFT, 2618 T6, 5083 0, 5251 H4-H8, 5454 0 H2-H4,6063 T6,6082 T6,7075 T6 2014 T6, 2618 T6, 5083 0, 5251 H4-H8, 5454 H2-H8, 7075 T6 2618 T6 * Reproduced by permission of the heirs of Dr E. A. West. t Based, in general, on static tests undertaken at temperature after soaking...

200250 100 150 200 250

LM4, LM5, LM6, LM10 TB, LM12 TF, LM13 TF, LM25 TF, L35, 2L92 TF LM4, LM5, LM6, LM10 TB, LM12 TF, LM25 TF, L35, 2L92 1200 H8, 2014 T6, 2618 T6, 3103 H4-H8, 5083 0, 5251 0 H4-H8, 5454 0 H2-H4, 6063 T6, 6082 T6, 7075 T6 1200 H8, 2014 T6, 2618 T6, 3103 H4-H8, 5083 0, 5251 0 H4-H8, 5454 0 H2-H4, 6063 T6, 6082 T6, 7075 T6 2014 T6, 2618 T6, 5083 0, 5251 0 H4-H8, 5454 0 H2-H4, 7075 T6 5083 0, 5454 0 H2-H4, 6082 T6, 7075 T6 LM4, LM5, LM6, LM10 TB, LM12 TF, 1200 H8, 2014 T6, 2618 T6, 3103 H8, LM5, LM10...

Htb1

Gl, LG2, LG4, ABl, AB2 HTB1, LG2, LG4 * Reproduced by permission of the heirs of Dr E. A. West. Table 1.24 Initial guide to selection of copper and copper alloys for applications at raised temperatures* Superheated steam valves and fittings Spot, seam and flash butt welding electrodes and dies CA103, CA104, CA105 CC101, CC102 C108 CC101, CC102 CC101, CC102 C108, CB101, CC101 A most important point to consider in the selection of aluminium is the cyclical price variation. The supply of aluminium...

Bibliography

Bibliography For Metal Forming Process

ALTING, L., Manufacturing Engineering Processes, Marcel Dekker, New York (1982) AVITZUR, B., Metal Forming Processes and Analysis, McGraw- Hill, New York (1968) BLAZYNSKI, T. Z., Metal Forming Tool Profiles and Flow, Macmillan, London (1976) BLAZYNSKI, T. Z., Applied Elasto-Plasticity of Solids, Macmillan, London (1983) BLAZYNSKI, T. Z., Design of Tools for Deformation Processes, Elsevier Applied Science, London (1986) BLAZYNSKI, T. Z., Plasticity and Modern Metal-Forming Technology, Elsevier...

Bs 1471 Bs 1472

Aluminium and aluminium alloy ingots and castings Wrought aluminium and aluminium alloys for general engineering purposes plate, sheet and strip Drawn tube Bars, extruded round tubes and sections Anodic oxide coatings on wrought aluminium for external architectural applications Anodic oxidation coatings on aluminium Methods for crack opening displacement (COD) testing Code of practice for the design of aluminium structures See also BS L series and DTD specifications for defence materials.

814 Honing practice

Honing uses the complete range of abrasive materials including silicon carbide, aluminium oxide, diamond and cubic boron nitride (CBN). In the honing process, the abrasive is in continuous contact over a large area of the component. In order to achieve both self-sharpening and free cutting requires very careful selection of the abrasive type, grit size and bond hardness. The combination of grit and bond should satisfy the above requirements and also give an economic abrasive life. The honing...

92 Welding soldering and brazing

Welding is used for joining metals so that the physical and mechanical properties of the parent metal are reproduced in the joint. The integrity of a welded component, which has metallurgical continuity across the joint, is also characterised by properties such as pressure tightness, or heat and corrosion resistance. These properties have contributed to the rapid development, both technical and economic, in all fields including nuclear power, chemical engineering, bridge building, offshore...

630

Nearest equivalent specifications BS 1449 1970 284S16 540 1240 Readily hardens by cold working. Structural steels for applications where high strength is required. Nearest equivalent specifications BS 1449 1970 301S21 510 790 For spoons and forks, holloware, architectural and shop fittings, domestic catering, food manufacturing, dairy and brewery equipment. Nearest equivalent specifications BS 970 1983 302S25 Bs 1449 1970 302S17, 302S25 510 790 A general purpose austenitic free-cutting steel....

467 Orbital forging

The orbital forging process is intended to allow smaller machines to be used for suitable forging operations. This process is based on the simple concept that the axial force required to effect a desired deforming zone between the platens is confined to a small region. The plastic zone is then moved through the work piece, thus resulting in progressive deformation. The plastically deforming region is formed by initially indenting with a conical platen into the work piece which is supported by a...

3

Effective radius when roll is slipping faster than tube Effective radius when tube is slipping faster than roll Figure 4.51 Effective radius in roll design role in the design and operation of reducing mills and depends on the rolling condition. No-stretch conditions prevail when a tube passes through a single stand, so that its diameter is reduced without any external axial forces being applied to it the thickness also increases. In this case, where the change in wall thickness occurs purely as...

1318 Tool steels

The name 'tool steels' BS 4659 1971 and AISI SAE 'Tool steels' covers a wide variety of steels used for forming and cutting materials which have as essential properties high hardness, resistance to wear and abrasion and adequate toughness. There are, or have been, some 82 AISI standard steels, 25 BS steels and many non-standard steels, but it should be possible to meet almost all requirements from the 10 steels listed here. Carbon steels are used for hand tools and other applications where high...

22

0.03 max. 17 13.5 4.5 Resistance to strong organic acids at elevated temperatures. Increased reistance to pitting. Applicable below 300 C. Resists intergranular attack. Weldable for most applications water jets . Their metallurgy is similar to that of high speed steels. A recommended steel is AISI H13 BS 4659 BH13 this steel has the highest and deepest hardness of the hot work steels. Cold work steels are used for forming cold materials and resistance to abrasive wear is of highest importance....

138 Electrical steels

Electrical steels comprise a class of steel strip which is assembled and bolted together in stacks to form the magnetic cores of alternating current plant, alternators, transformers and rotors. Its essential properties are low losses during the magnetising cycle arising from magnetic hysteresis and eddy currents, high magnetic permeability and saturation value, insulated surfaces, and a low level of noise generation arising from magnetostriction. These parameters are promoted by maintaining the...

134 Mechanical working of metals

This topic is included for convenience in this section on ferrous metals, but is more widely applicable. A metal is worked mechanically either to generate a shape more economically than can otherwise be obtained or to provide improved properties in strength, ductility and or fatigue not creep for which a cast structure is superior . The improvement in properties may, overall, be directional to resist a directional stress system, or statistical to ensure that a lower percentage of components...

Abc

Figure 1.24 Isothermal diagrams showing the heat treatment of steel, a Quenching and tempering to give tempered martensite. b Austempering to give lower bainite. c Martempering to give tempered martensite. d Annealing to give ferrite and peariite. e Isothermal annealing to give ferrite and peariite Figure 1.24 Isothermal diagrams showing the heat treatment of steel, a Quenching and tempering to give tempered martensite. b Austempering to give lower bainite. c Martempering to give tempered...

434

C 0.12 0.20 Cr 16.0 18.0 Ni 2.00 3.00 C 0.10 max. Cr 16.0 18.0 Mo 0.90 1.30 Ni 0.50 max. 850 1000 General engineering. Pump and valve parts in contact with non-ferrous metals or graphite packing . Nearest equivalent specifications BS 970 431S29 Ferritic stainless. Motor car trim. Nearest equivalent specifications BS 1449 434S19 Free machining versions of 13 Cr steels are available to BS 970 416S21, 416S29, 416S37. than nickel. These steels can be cold worked to higher strengths than the '300'...

Bs970 347s17 Equivalent Specification

Cr 16.5 18.0 Ni 10.0 13.0 Mo 2.25 3.00 C 0.07 max. Cr 16.5 18.5 Ni 10.0 13.0 Mo 2.25 3.00 N 0.25 max. C 0.03 max. Cr 17.5 19.5 Ni 14.5 17.0 Mo 3.00 4.00 C 0.06 max. Cr 17.5 19.5 Ni 12.0 15.0 Mo 3.00 4.00 C 0.08 max. Cr 16.5 18.0 Ni 11.0 14.0 Mo 2.25 3.00 Ti 4 x C 0.60 C 0.08 max. Cr 17.0 19.0 Ni 9.00 11.0 Ti 5 x 00.10 C 0.08 max. Cr 17.0 19.0 Ni 9.00 11.0 Ti 5 x C 0.70 C 0.12 max. Cr 17.0 19.0 Ni 8.00 11.0 Ti 5 x C 0.90 S 0.15 0.30 C 0.08 max. Cr 17.0 19.0 Ni 9.00 11.0 Nb 10 x a...

Iiiiii1

Figure 1.20 Continuous cooling time-temperature-transformation diagrams, a Applicable to forgings, plates and sections, b Applicable to heat treatment of bars These products exemplify more than any others the quality improvements that the improvements in steelmaking described in Section 1.3.3 have produced in tonnage steels. 1 lower maximum sulphur levels as low as 0.008 2 improved deoxidation with low inclusions and controlled morphology 3 very low hydrogen levels resulting from vacuum...