GOST 24648-90

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  ГОСТ 24648-90

GOST 24648−90 Cast iron casting. Sampling and specimen preparation for mechanical testing

GOST 24648−90

Group В89

INTERSTATE STANDARD

CAST IRON CASTING

Sampling and specimen preparation for mechanical testing

Pig iron for castings. Sampling and making the specimens for mechanical testing

ISS 77.080.10
OKP 41 1000

Date of introduction 1992−07−01

INFORMATION DATA

1. DEVELOPED AND INTRODUCED by the Ministry of heavy machine building of the USSR

2. APPROVED AND put INTO EFFECT by Decision of the USSR State Committee on management of quality and standards from 24.07.90 N 2250

3. The standard fully conforms to the standard of the CMEA 728−88

4. The standard complies with international standards ISO 185−88, ISO 1083−76, ISO 2892−73, ISO 5922−81 in terms of sampling and fabrication of specimens for mechanical testing

5. REPLACE GOST 24648−81

6. REFERENCE NORMATIVE AND TECHNICAL DOCUMENTS

7. Limitation of actions taken by Protocol No. 7−95 Interstate Council for standardization, Metrology and certification (ICS 11−95)

8. REISSUE


This standard specifies the requirements for cast samples, blanks and samples for mechanical testing of all types of cast iron casting.

1. TERMS AND DEFINITIONS

1.1. Cast alloy — casting or high tide, from which are selected the workpiece.

1.2. Blank — molded part samples or castings, which produce a sample.

1.3. The sample is a machined part of the workpiece or raw cast sample of prescribed shape and size, designed to determine the mechanical properties.

2. SAMPLES OF CAST IRON WITH LAMELLAR GRAPHITE

2.1. Separately cast samples are made with a diameter (30) mm and a length exceeding the length of the sample not less than 40 mm.

2.2. The samples cast into molds made of molding compounds on the basis of quartz sand or other compounds with similar thermophysical properties.

2.3. Samples for evaluation of mechanical properties of cast iron in castings produced in metal molds, allowed to cast in metal molds. Shape, size of samples and the level of mechanical properties thus set in the technical documentation for the casting.

Allowed cutting blanks directly from the walls of the casting. The shape, the dimensions of the workpieces, place them cut-and-level mechanical properties set in the technical documentation for the casting.

2.4. When casting two or more samples in one form the distance between the samples and between the cavity and the mold surface should not be less than 50 mm.

2.5. Sample beat from the mold after cooling to a temperature below 500 °C (not less than 35 minutes after pouring). Further cooling of samples should be on dry lining.

2.6. Recommended shapes and sizes of tides to castings weighing over 200 kg and a wall thickness of over 20 mm are given in Appendix 1.

2.7. Samples for tensile tests must comply with the devil.1, 2 or 3. The axis of the sample should coincide with the axis of the sample.

Damn.1

Damn.2

Damn.3

The shape and size of the heads, samples can be changed in accordance with the shape and size of the clamping device test machine.

When cutting pieces of walls of the castings are allowed in the technical documentation set the dimensions of the samples according to GOST 1497.

2.8. Samples for hardness test are taken from the heads of specimens after tensile tests or cut directly from samples.

The samples are cut so that the place of the hardness was not less than 35 mm from the end of the sample.

Samples shall conform to the requirements of GOST 9012.

3. SAMPLES OF CAST IRON WITH GLOBULAR AND VERMICULAR GRAPHITE

3.1. The type, shape and dimensions of samples for making samples shall be as given in hell.4 and in table.1 or hell.5 and in table.2.

Damn.4

Table 1

________________
* Size for reference.

Damn.5

Table 2

________________
* Size for reference.


Type of sample set depending on the wall thickness of castings. In the manufacture of thin-walled castings and castings in metal molds, it is recommended to use samples of type I, for thick-walled castings in sample types III and IV.

The thickness of the mold around the sample must be not less than:

40 mm — for types I, IIA, IIB samples in a U-shape and types I and II samples V-shape;

80 mm — for types III and IV samples are U — and V-shaped.

Allowed mould thickness around samples of types III and IV, not less than 50 mm.

3.2. The samples cast into molds made of molding compounds on the basis of quartz sand or other compounds with similar thermophysical properties.

3.3. Sample beat from the mold after cooling to a temperature below 500 °C. Further cooling of samples should be on dry lining.

3.4. Samples for determining the mechanical properties of cast iron with spheroidal and vermicular graphite, modified in form, are made from high tides in the casting.

3.5. Allowed cutting blanks directly from the walls of the casting. The shape, the size of the workpieces and place them cuttings set in the technical documentation for the casting.

The recommended shape and size of the tides to castings given in Appendix 2.

3.6. The shape and dimensions of samples for tensile tests must comply with the devil.6. The axis of the sample should coincide with the axis of the sample. The shape and size of the heads, samples can be changed in accordance with the shape and size of the clamping device test machine.

Damn.6

When cutting pieces of walls of the castings are allowed in the technical documentation set the dimensions of the samples according to GOST 1497.

3.7. Samples for hardness test are taken from the heads of specimens after tensile tests or directly from the blanks. Samples shall conform to the requirements of GOST 9012.

3.8. Samples with V-shaped cut for testing the impact strength shall conform to the requirements of GOST 9454.

4. SAMPLES OF MALLEABLE CAST IRON

4.1. Tensile tests performed on the mechanically untreated samples with the diameter of the working part 9, 12 and 15 mm.

Allowed to use samples with a diameter of the working part 8 and 16 mm.

The shape and dimensions of mechanically untreated samples for tensile tests is shown in hell.7 and in table.3.

Damn.7

Table 3

mm

4.2. The shape and size of the heads, samples can be changed in accordance with the shape and size of the clamping device test machine.

The estimated diameter is measured with an accuracy of 0.1 mm. displacement in the plane of contact of the sample should not exceed 0.2 mm.

4.3. The samples cast into molds made of the same molding compounds, and molds for castings. In one form cast not less than four samples.

Upon receipt of the castings in raw forms is allowed to cast the samples in dry form.

4.4. Samples beat from the mold at a temperature close to the temperature of the shake-out of castings.

4.5. After removal of the Gating system and the Burr samples were subjected to heat treatment with castings.

4.6. The hardness is determined on the heads of specimens after tensile tests.

In place of determining the hardness of the surface layer removed to a depth of not less than 4 mm.

Samples shall conform to the requirements of GOST 9012.

5. MARKING

5.1. Marking of cast samples once applied to exclude its damage.

Allowed marking of samples of steel tags installed in the form during casting.

5.2. Place the labeling on the samples selected so that it does not affect the test results.

ANNEX 1 (reference). THE SHAPE AND SIZE OF THE TIDES TO CASTINGS OF CAST IRON WITH LAMELLAR GRAPHITE

ANNEX 1
Reference

For tensile tests

Damn.8

Note. Values given in parentheses — the second version of the size of the tides.

Hardness

Damn.9

ANNEX 2 (informative). THE SHAPE AND SIZE OF THE TIDES FOR IRON CASTINGS WITH SPHEROIDAL AND VERMICULAR GRAPHITE

ANNEX 2
Reference

Damn.10

Table 4

mm

Notes:

1. In the case of changing the size of the tides take ; .

2. Allowed not less than 155 mm.

3. Tides hardness should correspond to the features.9.