BS 1387
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Dimensions and masses are in accordance with ISO 65 'Light Series
II'.
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Maximum and minimum outside diameters meet the requirements of ISO
65.
- Thicknesses and masses are in accordance with ISO 65.
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The values have been calculated to at least five significant
figures in accordance with the formula in ISO 65:
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For the metric system:
- m = 0.0246615 * (D - t)t kg/m (A)
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For the inch system:
- m = 10.68142† (D - t)t lb/ft (B)
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Where:
- D = specified outside diameter
- t = specified thickness
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This coefficient takes into account a density equal to 7.85
kg/cm².
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This coefficient takes into account a density equal to 489.8
lb/ft².
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The lb/ft value is then converted to kg/m by multiplying by
1.4882.
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The mean value in kg/m is {(A) + (C)}/2 and is rounded to three
significant figures.
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The equivalent mean value in lb/ft is found by dividing the
rounded value by 1.4882 and is then rounded to three significant
figures.
Tubes and Sockets
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This Indian Standard was adopted by the Indian Standards
Institution on 30 November 1982, after the draft finalized by the
Steel Tubes, Pipes, and Fittings Sectional Committee had been
approved by the Structural and Metals Division Council.
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This Indian Standard has been prepared to meet the requirements of
lancing pipes used by the steel industry.
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Requirements for ceramic and other special coatings to enhance the
life of the pipes will be added in due course after collecting the
necessary data.
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This standard contains clauses 2.4, 11.1, and 12.1 which call for
agreement between the purchaser and the manufacturer.
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For the purpose of deciding whether a particular requirement of
this standard is complied with, the final value, observed or
calculated, expressing the result of a test or analysis, shall be
rounded off in accordance with IS: 2-1960. The number of
significant places retained in the rounded-off value should be the
same as that of the specified value in this standard.
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This standard covers the requirements of butt-welded, screwed and
socketed, and plain end mild steel pipes intended for use in
oxygen lancing.
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For the purpose of this standard, the following definitions shall
apply.
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Black Pipe: Pipe as manufactured, but without any
subsequent surface treatment.
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Length of Screwed and Socket Pipe: The length of
the pipe inclusive of the socket.
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Nominal Bore: A size reference denoting the
approximate bore of the pipe. For each size of pipe, the outside
diameter is fixed by the corresponding screw thread dimensions of
IS: 554-1975 and therefore, the actual bore of each size of pipe
will vary according to the thickness.
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Random Length: Normal manufacturing lengths which
may vary over a range of several meters. Alternatively, a length
range agreed to between the purchaser and the manufacturer.
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Socket: The screwed coupling utilized in joining
the pipes together.
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Pipe (Tube): A long, hollow, open-ended object of
circular or other cross-section. The term 'pipe' is synonymous
with the term 'tube'.
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Note 1: The length of the pipe inclusive of
the sockets means the pipe length measured with a socket
fitted at one end to handling-tight.
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Note 2: Handling tight means that the socket
is so tight fitting that it should not fall down during
handling or transit.
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Note 3: The term 'socket' is synonymous with
the term 'coupler'.
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Mild steel pipes covered by this standard shall be designated by
their nominal bore and shall be further classified as 'light',
'medium', and 'heavy' depending on the wall thickness.
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Mild steel sockets shall be designated by the respective nominal
bore of the pipe for which it is intended.
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General requirements relating to the supply of mild steel pipes
and sockets shall conform to IS: 1387-1967.
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Lancing pipes shall be supplied with any of the following
combinations as specified by the customer:
- Plain end
- Both ends screwed and one end socket
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Pipes shall be manufactured from mild steel made by open hearth,
electric, or any of the oxygen processes.
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Steel pipes and sockets shall be manufactured by one of the
following processes:
- Continuous oxy-acetylene gas welded pipes (OAW)
- Electric resistance welded (ERW)
- High frequency induction welded (HFIW)
- Hot-finished welded (HFW)
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Pipes made by manual welding are not covered by this
specification.
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Hand welding of sockets may be permitted provided the test
requirements for the sockets covered by the standard are complied
with.
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Sockets may also be manufactured from rods provided the test
requirements for the sockets covered by the standard are complied
with.
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Note: The Socket Length shown in Table meets the
requirements of ISO 50, but the minimum length B has been
increased to allow for the chamfer at the ends of the sockets and
is based on B = 2L + 3.5P.
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The dimensions of pipes shall be in accordance with Table 1, 2,
and 3 subject to the tolerances permitted in 8. Dimensions of
sockets shall be in accordance with Table 4.
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Nominal masses of 'light', 'medium', and 'heavy' black pipes shall
be as specified in Table 1, 2, and 3 respectively.
1. Manufacture
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Manufacture of the steel: The steel shall be
produced by the electric or one of the basic oxygen processes and
shall be fully killed, semi-killed, or rimmed.
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Manufacture of the product: Tubes shall be
manufactured by a welded process. Sockets shall be manufactured by
a seamless or welded process.
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Chemical composition: The chemical composition of
the steel shall comply with Table 1.
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Heat Treatment: Tubes shall be supplied in the
annealed or normalized condition, the as-welded condition, the
as-welded condition with the weld zone heat-treated, or after a
hot finishing process.
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Note 1: Chemical analysis of the finished product
is not required.
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Note 2: This steel is regarded as being weldable.
However, care should be taken and welding should be carried out in
accordance with the appropriate British Standards.
2. Mechanical properties
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The mechanical properties at room temperature shall be as given in
Table 1.
3. Appearance and soundness
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Small imperfections which do not intrude on the minimum thickness
or which can be dressed out such that the thickness after dressing
remains within the tolerance limit shall be deemed not to affect
compliance with this standard. Surface imperfections shall not be
peeled.
- Screw threads shall comply with the requirements of BS 21.
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The ends shall be cut cleanly and normally square with the axis of
the tube and be free from excessive burrs.
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The tubes shall be straight to within 1 in 500 as measured at the
center of the length.
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The tubes shall not include welds used for joining lengths of
strip.
4. Joints
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All screwed tubes and sockets shall be threaded in accordance with
BS 21 except as provided below and except that on light tubes the
length of useful thread shall be reduced to 80% of that shown in
column 12 of Table 2 of BS 21:1985.
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Where light tubes approach the lower limits of outside diameter,
some 'black' threads (perfect at the root and imperfect at the
crest) are to be expected beyond the gauge plane, but such 'black'
threads shall be deemed not to affect the compliance of the tubes
with this standard.
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Tubes shall be supplied screwed with taper threads and fitted with
one screwed socket having a parallel thread unless it is
specifically requested by the purchaser in his enquiry or order
(see Appendix A) that the tubes shall be supplied without sockets
or supplied with a socket having a taper thread.
5. Dimensions and Tolerances
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Dimensions: The dimensions of tubes shall be as
given in Table 3, 4, and 5. Dimensions of sockets shall be as
given in Table 6.
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Tolerances: The tolerances on the outside
diameter, thickness, mass, and length shall be as follows:
6. Testing
A. Visual Inspection
Each tube shall be inspected to ensure compliance with Section 2.3.
This visual inspection will ensure that the tubes meet the specified
requirements for appearance, dimensions, and any visible defects.
B. Tensile Test
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The tensile test shall be conducted in accordance with BS 18: Part
4.
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The following parameters shall be determined: tensile strength
(Rm), yield strength (Ro), and elongation (A).
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The results must comply with the requirements outlined in Table 1.
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For yield strength, either the upper yield stress (Ro) or the 0.5%
proof stress (total elongation) A, 0.5 shall be determined.
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The percentage elongation shall be reported with reference to a
gauge length of Lo=5.65 √So. If other gauge lengths are used, the
corresponding percentage gauge length Lo=5.65 √So shall be
obtained with reference to BS 3894: Part 1.
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In cases of dispute, a gauge length of Lo=5.65 √So shall be used.
C. Bend Test (Whole Tube)
- The bend test applies to tubes up to and including DN 50.
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Tubes shall withstand the test without showing any signs of
fracture or failure.
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The test shall be carried out using a tube bending machine, with
the tube bent round a grooved former of the radius as specified.
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The tubes shall be bent with the weld at 90° to the plane of
bending. The tubes shall not be filled for this test.
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(a) Tubes which have not been hot-dip zinc coated shall be bent
cold, without cracking, through 180° round a groove with a
diameter equal to six times the outside diameter of the tube as
given in Tables 3, 4, 5.
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(b) Hot-dip zinc coated tubes shall be bent cold without
cracking through 90° round a former with a radius equal to eight
times the outside diameter of the tube.
D. Flattening Test
- The flattening test applies to tubes greater than DN 50.
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A ring, not less than 40 mm in length, taken from one end of each
selected tube, shall be flattened cold between parallel flat
platens.
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The ring shall be flattened without showing either cracks or flaws
until the distance between the platens is no greater than 75% of
the original outside diameter of the tube.
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No cracks or flaws shall occur in the metal, except in the weld,
until the substance between the platens is less than 60% of the
original outside diameter.
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The weld shall be placed at 90° to the direction of flattening.
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Note: Slight premature cracking at the edges is not deemed to
affect compliance with this standard.
E. Leak Tightness Test
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Black tubes shall be tested for leak tightness at the
manufacturer's works.
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The test shall either be a hydraulic test at a pressure of 50
bars, with the pressure maintained sufficiently long for proof and
inspection, or an eddy current test in accordance with Appendix B.
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Note: The choice of test is at the discretion of the
manufacturer.
F. Bore Test (Hot-Dip Zinc Coated Tubes Only)
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The bore test shall be conducted to ensure compliance with the
specified requirements.
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Hot-dip zinc coated tubes of DN 8 up to and including DN 25 shall
have a rod, 230mm in length, of the appropriate diameter specified
in the table, passed through them after hot-dip zinc coating to
ensure a free bore.
7. Manufacturer's Certificate
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The manufacturer shall provide a certificate certifying that the
tubes supplied comply with this British Standard.
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Note: This certificate will only be provided when specified or
requested by the customer in accordance with Appendix A.
Dimensions & Nominal Masses of Black Steel Pipes (Light)
6 |
10.1 |
9.7 |
1.8 |
0.361 |
0.364 |
8 |
13.6 |
13.2 |
1.8 |
0.517 |
0.521 |
10 |
17.1 |
16.7 |
1.8 |
0.674 |
0.680 |
15 |
21.4 |
21.0 |
2.0 |
0.952 |
0.961 |
20 |
26.9 |
26.4 |
2.35 |
1.41 |
1.42 |
25 |
33.8 |
33.2 |
2.65 |
2.01 |
2.03 |