The annealing of steel castings is frequently adopted, the castings being re-heated in a specially constructed furnace, and allowed to cool gradually for certain specified periods. All the tests enumerated in the following tables are on annealed specimens.

The bending tests are commonly carried out on square or round bars bent cold by an hydraulic press over a curved block, the radius of which is specified, and it is well for the student in drawing up his requirements in this particular to be clear as to the meaning of the clause defining the angle through which the bar is to bend. Thus to specify that a bar shall bend to an angle of 45°, appears to leave it an open question as to whether it shall bend through an angle of 45° or through an angle of 135°. The use of the term "interior angle," or, better still, the figured diagram, will, however, leave the requirement intelligible and free from dispute. Considerable variations will be observed in the tables with respect to the angles bent through, as compared with the ultimate elongation in tensile tests, and the causes of this variability are not very obvious. It is possible, however, that they are partly due to differences of conditions in the process of annealing. The following table, No. 19, shows, in general terms, the practice with respect to annealing of steel castings, position of test-pieces, etc., of five of the leading cast-steel manufacturers in this country at the present time.

Table No. 19. Showing The Practice With Respect To The Annealing Of Steel Castings, And Position Of Test-Pieces, Of Five Leading Cast-Steel Manufacturers In Great Britain

Description of furnace.

Siemens open-hearth steel furnaces.

Special Siemens-Martin furnaces.

Siemens- Martin open-hearth furnaces.

Siemens- Martin open-hearth furnaces.

Siemens- Martin open-hearth furnaces.

Annealing furnace.

Secret method of annealing. Castings annealed for at least ten days.

Castings annealed in special furnaces heated by gas for about four to six days.

Castings about seven days in annealing furnace.

No information given.

Castings heated to a bright cherry-red for about three days.

Position of test-pieces on castings and method of annealing them.

These are always attached to the main casting and annealed with them.

Their position on the casting is usually kept as near as possible to the runner. The tensile and bending specimens are taken from the same piece.

These are always attached to the main casting and annealed in position.

They are not cast in any particular way on the piece. The tensile and bending specimens are taken from the same piece.

These are always attached to the main casting and annealed in position.

The test-piece is invariably at the bottom of the casting, the runner being at the top. The tensile and bending specimens are taken from the same piece.

These are always attached to the main casting and annealed in position.

The test-pieces are usually placed at the joints of the moulding boxes. The position of the runner varies. The tensile and bending specimens are separate on the casting.

The test-pieces are cast in a vertical position at the bottom of the mould in the case of large castings.

They are cast separately with smaller pieces. They are annealed with their castings. The tensile and bending specimens are taken from the same piece.

The great advantage possessed by cast steel over cast iron in the ductility exhibited even by the smallest angle bent through, given in the table, is sufficiently obvious.

Fig. 4 is an elevation of a typical specimen of cast-steel test bar nominally 1 inch square, bent by hydraulic pressure over a block having a radius of 1 inch, to an interior angle of 70°, and remaining unbroken.

Fig. 5 is a section of the bar on the line a-b, showing the section of the bar, with its square edges machined or filed off. (The whole bar was machined.) Fig. 6 gives the section through the bend of the bar on the line c, d, and shows the flow of material due to the process, the concave fibres in compression being laterally extended, while the convex surface is contracted, accompanied by a slight hollowness in the sides, the whole figure well exhibiting the ductility of the material.

Scale, half full size.

Fig. 4. Scale, half full size.

Scale, half full size.

Fig. 5. Scale, half full size.

Scale, half full size.

Fig. 6. Scale, half full size.

The tensile tests are made in the usual way on specimens which are sometimes 8 inches in length between the shoulders, but more commonly 2 inches in length, the latter dimension being that usually preferred by the steel founder, as being more advantageous from his point of view.

Table No. 20. Tensile And Bending Tests On Cast-Steel Bars

All bars machined approximately 1 inch square (with the exceptions described) for bending tests, and prepared in the usual way for tensile tests.

Bending tests were made over a block having a radius of 1 inch, and were bent cold under hydraulic pressure. All specimens, both for bending and tensile tests, were annealed with the castings which they were intended to represent.

The Material For The Greater Part Of The Castings Was Supplied Under The Specification Given On P. 19

No. of test.

Description of casting.

Ultimate tensile strength. Tons per sq. inch.

Elongation in 8 inches.

Per cent.

Elongation in 2 inches. Per cent.

Angle through which test-piece was bent. Degrees.

Remarks.

1

Pawl racks

18.7

5.0

• • •

All these results being so much below the specified requirements, the castings represented were rejected

2

"

18.7

3.1

3

"

19.8

3.7

4

"

22.5

2.25

• • •

5

"

24.0

4.25

6

"

242

3.75

7

"

23.3

2.75

8

"

21.8

2.5

9

"

32.5

14.75

Good fracture

10

"

26.75

10.50

"

11

"

37.50

16.75

"

12

"

26.90

9.75

"

13

"

27.50

15.75

"

Below the spe-cified elongate tion

14

"

29.75

8.0

15

"

32.1

18.75

Good fracture

16

"

32.2

20.5

"

17

"

33.6

20.0

"

18

"

33.9

20.75

"

19

"

33.85

11.0

"

20

"

32.45

12.0

"

21

"

31.5

22.2

"

22

"

31.1

13.5

"

23

"

31.1

21.25

"

24

"

30.9

23.25

"

No.

of test.

Description of casting.

Ultimate tensile strength. Tons per sq. inch.

Elongation in 8 inches.

Per cent.

Elongation in

2 inches.

Per cent.

Angle through which test-piece was bent. Degrees.

Remarks.

25

Pawl racks

29.1

23.0

...

• • •

Good fracture

26

"

29.0

23.5

...

• • •

"

27

"

30.2

19.75

...

• • •

"

28

"

28.6

19.5

...

• ••

"

29

"

29.8

23.1

...

• • •

"

30

"

29.2

19.5

...

• • *

"

31

"

31.0

23.0

....

• • •

"

32

"

30.4

24.5

...

• ••

"

33

"

32.1

21.8

...

• • •

"

34

"

32.0

20.5

...

• • •

"

35

"

31.5

19.0

...

• • •

"

36

"

32.0

21.75

...

• ••

"

37

"

31.75

24.75

...

• ••

"

38

"

33.25

21.5

...

• • •

"

39

"

27.85

• • •

...

• • •

Broke outside datura points

40

"

34.15

22.25

• • •

These specimens were cut from the racks themselves, and not from runners cast at the same time as the racks

411

Bollards

31.8

26.02

105

42

"

31.02

26.0

95

43

"

32.8

21.0

90

44

"

31.5

21.5

115

45

"

33.25

20.0

110

46

"

32.9

20.5

120

47

"

31.9

15.0

90

48

"

31.8

170

88

49

"

31.55

15.0

87

50

"

32.4

16.5

105

51

"

32.6

16.0

100

52

"

31.85

16.0

102

1Test Nos. 41 to 63 inclusive for bending were made on bars ⅞ inch to 15/16 inch square. Bending tests Nos. 64 to 97 inclusive were made on 1 inch diameter round bars.

2 specimens For Testing In Tension Were From 0.74 To 0.81 Inch In Diameter, And From 043 To 051 Square Inch In Area

No. of test.

Description of casting.

Ultimate tensile strength. Tons per sq. inch.

Elongation in 8 inches.

per cent.

Elongation in

2 inches.

Per cent.

Angle through which test-piece was bent. Degrees.

Remarks.

53

Bollards

29.6

16.0

110

54

"

30.4

14.0

115

55

"

29.4

18.0

105

56

"

32.6

18.0

105

57

"

32.75

17.0

110

58

"

31.80

17.0

105

59

"

32.75

18.0

95

60

"

32.90

19.0

105

Sound

61

"

31.8

17.0

110

"

62

"

31.6

18.0

105

Broke

63

"

31.3

16.0

100

Sound

64

"

33.5

19.0

96

"

65

"

34.6

18.5

105

Broke

66

"

33.4

14.5

95

"

67

"

34.8

18.0

105

Sound

68

"

28.8

18.0

100

Broke

69

"

30.0

16.0

100

Sound

70

"

28.8

19.0

113

Broke

71

"

33.8

16.0

100

Sound

72

"

34.3

16.0

90

"

73

"

30.9

24.0

90

"

74

"

30.6

23.0

90

"

75

"

30.5

25.0

90

"

76

"

33.3

26.0

90

"

77

"

32.0

26.0

90

"

78

"

32.9

22.0

95

"

79

"

32.2

23.0

90

"

80

"

32.4

26.0

90

"

81

"

32.2

23.0

90

"

82

"

32.5

20.0

90

"

83

"

32.0

27.0

90

"

84

"

30.8

24.0

90

"

85

"

32.3

23.0

90

"

86

"

33.0

30.0

90

"

87

"

33.8

25.0

90

"

88

"

33.0

28.0

90

"

89

"

33.7

21.0

90

"

90

"

34.2

27.0

90

"

91

"

33.7

22.0

90

"

92

"

34.2

26.0

90

"

93

"

32.2

25.0

90

"

94

"

35.2

21.0

90

"

95

"

34.2

23.0

90

"

96

"

33.1

23.5

90

"

97

"

33.2

23.0

90

"

No. of test.

Description of casting.

Ultimate tensile strength. Tons per sq. inch.

Elongation in 8 inches.

Per cent.

Elongation in

2 inches.

Per cent.

Angle through which test-piece was bent. Degrees.

Remarks.

98

Roller 1

Path

Castings

32.2

• ••

19.0

45

Sound

99

"

29.6

• • •

28.0

50

"

100

"

29.0

• • •

14.0

50

"

101

"

31.3

• . •

19.0

50

"

102

"

28.9

• • .

13.0

51

"

103

"

33.5

11.5

• ••

45

Broke

104

"

31.0

• • .

28.0

50

Sound

105

"

29.1

12.5

•• •

50

"

106

"

30.3

• • ..

29.0

50

"

107

"

29.1

• • •

31.0

60

"

108

"

27.3

• • •

19.0

60

"

109

'

29.4

12.0

• • •

70

Broke

110

"

31.3

• • •

28.0

57

Sound

111

"

33.2

10.5

• • •

50

Broke

112

"

29.5

20.0

• • •

75

"

113

"

31.8

21.0

• • •

70

"

114

"

30.2

• • •

30.0

.50

"

115

"

28.8

26.0

• • •

48

Sound

116

"

27.0

13.5

• • •

51

"

117

"

29.4

13.5

• • •

75

Broke

118

"

32.2

• • ∙

16.0

45

Sound

119

"

29.2

25.0

• • •

50

"

120

"

29.3

15.0

■ • •

55

Broke

121

"

29.5

16.0

• • •

50

Sound

122

"

33.3

• • •

18.0

50

Broke

123

"

31.6

15.0

• • •

40

"

124

"

31.7

• ••

14.0

35

"

125

"

31.6

14.0

• • •

80

"

126

"

34.0

13.0

• • •

70

"

127

"

31.7

• • •

29.0

125

"

128

"

29.2

• • •

25.0

100

"

129

"

31.6

14.0

• • •

125

Sound

130

"

29.9

• • •

15.0

70

Broke

131

"

29.6

10.0

• • •

90

"

132

"

30.6

15.0

• • •

90

Sound

133

"

29.7

12.0

. • •

135

"

134

"

30.7

• • •

24.0

145

"

135

"

33.3

13.0

• • •

65

Broke

136

"

34.2

14.0

. • .

140

Sound

137

"

29.1

11.0

• • •

145

"

1 The Details Of These Roller Paths Are Given In Figs. 403, 404, And A Description Will Be Found On P. 410

No. of test.

Description of casting.

Ultimate tensile strength. Tons per sq. inch.

Elongation in 8 inches.

Per cent.

Elongation in

2 inches.

Per cent.

Angle through which test-piece was bent. Degrees.

Remarks.

138

Roller path castings

29.9

• • •

12.0

45

Broke

139

"

33.7

• • •

16.0

50

"

140

"

29.7

10.0

• • •

70

"

141

"

30.5

• • .

30.0

55

"

142

"

30.5

• • •

.5.0

130

"

143

"

29.7

10.0

• • •

70

"

144

"

31.2

11.0

• • •

75

"

145

"

28.1

• • •

28.0

145

"

146

"

31.1

• • •

150

80

"

147

"

29.8

12.0

• • •

75

"

148

"

30.2

• • •

20.0

145

Sound

149

"

26.1

• * •

8.0

85

Broke

150

"

27.8

• • •

10.0

70

"

151

"

29.6

• • •

18.0

70

"

152

"

29.2

• • •

23.0

95

"

153

")

31.5

• • •

19.0

95

154

"

31.2

• • •

16.0

90

Sound

155

"

29.6

• . •

10.0

90

Broke

156

"

27.9

17.0

• • •

100

"

157

"

29.9

• • •

24.0

75

"

158

"

30.5

• • •

19.0

55

"

159

"

32.1

• • »

21.0

60

"

160

"

32.4

• • •

20.0

105

"

161

"

28.5

• • •

10.0

45

"

162

"

33.9

• • •

24.0

45

"

163

"

30.5

• • •

17.0

105

"

164

"

28.0

• • .

21.0

70

"

165

"

30.2

• • •

29.0

52

Sound

166

"

31.7

15.0

•••

75

Broke

167

"

31.0

• • •

16.0

110

Sound

168

"

30.0

13.0

• • •

95

"

169

"

32.2

12.0

.. •

90

"

170

"

29.2

19.0

• • •

70

Broke

171

"

31.5

• • •

17.0

65

Broke

172

"

27.1

10.0

. • •

65

173

"

28.7

. • •

15.0

80

Sound

174

"

27.6

13.0

• • .

60

Broke

175

"

27.7

25.0

• • •

55

"

176

"

32.9

• • •

15.0

80

"

177

"

30.2

• ••

20.0

135

Sound

178

"

31.2

11.0

. ••

75

Broke

179

"

28.9

110

•••

62

"

180

"

30.1

13.0

. ••

52

to

No. of test.

Description of casting.

Ultimate tensile strength. Tons per sq.inch.

Elongation in 8 inches.

Per cent.

Elongation in 2 inches.

Per cent.

Angle through which test-piece was bent. Degrees.

Remarks.

181

Roller path castings

28.4

11.0

• • •

76

Broke

182

"

283

12.0

•••

67

"

183

"

28.7

10.0

• • •

122

Sound

184

"

32.2

• ••

26.0

65

Broke

185

"

28.0

10.0

• • •

95

"

186

"

31.2

• • •

25.0

77

"

187

"

30.0

11.0

• • •

75

"

188

"

32.0

15.0

• • •

145

Sound

189

"

27.5

18.0

• • .

40

Broke

190

"

27.6

8.0

• • •

60

"

191

"

27.9

8.0

• • •

87

"

192

"

28.8

8.0

• ••

67

"

193

"

30.3

15.0

• ••

85

"

194

Roller1 castings

29.2

•••

26.0

50

Sound

195

"

33.5

11.5

• ••

45

Broke

196

"

28.8

26.0

• • •

48

Sound

197

"

29.5

16.0

• ••

50

"

198

"

28.7

• • •

34.0

49

"

199

"

28.7

34.0

• ••

64

Broke

200

"

30.5

14.5

• • •

135

Sound

201

"

29.5

185

• • •

65

Broke

202

"

29.6

13.5

• • •

85

"

203

"

31.0

14.5

• • .

60

"

204

"

25.4

12.0

• • •

75

"

205

"

27.3

10.0

••.

80

"

206

"

27.9

12.5

• •

75

"

207

"

28.3

•••

19.0

150

Sound

208

"

25.4

135

• ••

80

Broke

209

"

29.4

13.5

• • •

115

"

210

"

29.6

19.0

.. •

95

"

211

"

29.7

16.0.

...

110

"

212

"

28.0

13.5

• •.

60

"

213

"

29.3

13.5

• •

70

"

214

"

81-1

14.0

• • •

105

Sound

215

"

28.0

20.0

• • •

90

Broke

216

"

29.2

• • •

24.0

45

"

217

"

29.0

• • •

26.0

55

"

218

"

29.2

• • •

26.0

50

"

219

"

29.4

• • •

25.0

50

"

220

"

28.9

• • .

28.0

45

"

1 The Details Of These Rollers Are Given In Figs. 405, 406, And A Description Will Be Found On P. 412

No. of test.

Description of casting.

Ultimate tensile strength. Tons per sq. inch.

Elongation in 8 inches.

Per cent.

Elongation in 2 inches.

Per cent.

Angle through which test-piece was bent. Degrees.

Remarks.

221

Roller castings

27.3

. • .

19.0

60

Sound

222

"

31.3

• • •

19.0

50

"

223

"

33.5

11.0

• ••

45

Broke

224

"

28.9

• •

28.0

45

Sound

225

"

29.1

12.0

• • •

50

"

226

"

27.3

• • •

19.0

60

"

Castings for machinery

227

Cast steel1

32.9

14.0

• • •

50

Broke

228

Cylinders for hydraulic rams

31.8

13.0

• • •

90

Sound

229

"

34.2

10.0

• •

90

"

230

"

27.8

20.0 2

• • •

90

"

231

"

28.9

21.0

• •

90

"

232

"

28.2

22.02

• • •

90

"

233

"

26.6

• • •

15.0

90

"

234

"

29.6

• • •

34.0

164

"

235

"

28.4

■ • •

26.0

155

"

236

"

35.0

• •

21.0

73

Broke

237

Pinions

33.0

• • •

25.0

85

"

238

"

34.7

• • •

27.0

90

Sound

239

"

28.2

• • •

35.0

180

"

240

"

35.6

• • •

15.0

85

"

241

"

34.2

■ • •

12.0

60

"

242

Bevel pinions

31.6

• • ■

8.5

55

•• •

243

"

32.2

• • •

12.03

• • •

•• •

244

Wheels

36.4

• •«

22.0

83

"

245

Clutches

30.2

• •»

12.0

78

Broke

246

"

32.0

• • ■

17.0

74

"

247

"

32.9

• • •

18.0

68

"

248

Crank discs

28.2

• •

35.0

164

"

249

"

29.6

• • •

34.0

73

"

250

Stuffing-box covers

31.6

• • •

31.0

180

"

251

"

31.4

• • •

29.0

180

"

252

"

29.0

• • •

30.0

180

Sound

1 These cylinders are referred to on p. 415.

2 Extension on 6 inches.

3 Re-test of No. 242.

No. of test.

Description of casting.

Ultimate tensile strength. Tons per sq. inch.

Elongation in 8 inches. Per cent.

Elongation in 2 inches.

Per cent.

Angle through which test-piece was bent. Degrees.

Remarks.

253

Sundry small castings

31.3

28.0

• • •

57

Broke

254

"

27.0

13.5

• • .

51

Sound

255

"

32.2

• • •

16.0

45

"

256

"

29.2

25.0

• • •

50

"

257

"

29.6

• ••

28.0

86

"

258

"

31.2

11.0

• • •

75

Broke

259

"

33.8

11.5

• • •

115

"

260

"

32.6

10.5

• • •

120

"

261

"

28.9

• ••

21.0

55

Sound

262

"

33.9

• • •

24.0

145

Broke

263

"

33.0

• ••

25.0

90

'

264

"

29.6

• • •

28.0

135

Sound

265

"

33.9

• • •

24.0

45

Broke

266

"

27.0

13.0

• • •

51

Sound

267

Brackets for sliding doors

30.5

18.5

...

• • •

• • •

268

36.0

15.7

• ••

• • •

• • •

269

"

29.8.

17.5

• • •

• • •

• • •

270

271

272

Crucible caststeel wheels for bogie waggons to carry 5 0-ton loads

35.0

390

36.5

• • •

30.0

• • •

On 2"

• • •

26.6

• • •

On 3"

• • •

29.3

• • •

"

273

Pinion

32.6

• • •

6.0 (test piece defective)

90

Sound

274

"

31.6

• • •

25.0

90

"

275

"

31.4

• • •

32.0

45

"

276

"

34.0

• • •

16.0

105

"

277

"

33.0

• • •

20.0

105

"

278

"

32.0

.• •

28.0

90

"

279

"

29.7

• • •

14.0

60

Broke

280

Bevel wheel

33.0

• •

27.0

90

Sound

281

"

33.8

• • •

30.0

95

"

282

"

39.0

• • •

20.0

90

"

283

Running wheel

34.8

• •

27.0

45

"

284

Curb ring

35.6

• • •

23.0

45

"

285

35.0

• •

23-0

90

"

286

"

37.0

• • •

22.0

60

"

287

"

32.0

• ■ •

32.0

90

"

288

Sundry cast-ings for vari-ous purposes

27.6

8.5

• ...

65

Broke

No. of test.

Description of casting.

Ultimate tensile strength. Tons per sq. inch.

Elongation in 8 inches.

Per cent.

Elongation in 2 inches.

Per cent.

Angle through which test-piece was bent. Degrees.

Remarks.

289

Sundry castings for vari-'ous purposes

30.5

• • •

18.0

77

Broke

290

"

312

•••

25.0

60

"

291

"

32.2

• • •

26.0

87

"

292

"

32.2

• • •

26.0

95

"

293

"

29.4

15.0

• • •

87

"

294

"

29.8

• • •

21.0

85

Sound

295

"

28.0

10.0

• • •

90

"

296

"

30.5

• •

18.0

65

Broke

297

"

30..8

• •

24.0

87

"

298

"

325

19.0

.. •

75

"

299

"

29.4

16.0

• • •

90

"

300

"

29.8

15.0

• • •

65

"

301

"

29.2

• . •

18.0

118

Sound

302

"

29.2

• • •

15.0

55

Broke

303

"

31.5

• • •

21.0

60

"

304

"

30.9

• • •

22.0

63

"

305

"

31.2

. • •

20.0

58

"

306

"

31.9

• • •

14.0

59

"

The following experiments on the transverse resistance to bending of cast-steel bars are of interest, more especially as similar tests are, so far as the writer knows, somewhat rare.