Iranian Classification Society Rules
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Section 3 Steel Tubes and Pipes
301. Application
The requirements in this Section apply to tests and inspection for the approval of manufacturing process of steel tubes and pipes as specified in Pt 2, Ch 1, Sec 4 of the Rules.
302. Data to be submitted
1. The following reference data in addition to those specified in 102. are to be submitted to the Society.
(1) Kind of products (e.g. Material grade, etc.)
(2) Method of melting process
(3) Method of ingot casting
(4) Fabrication method of
steel tubes and pipes (Fabrication method is to be classified seamless
steel tubes and pipes, welded steel tubes and pipes, electric-resistance welded steel tubes and
pipes, etc. For welded
steel tubes and pipes or electric-resistance welded steel tubes and pipes,
welding working standards are to be included.)
(5) Method of heat treating, etc.
2. Where raw materials for steel tubes and pipes are provided from multi-source or any part of the manufacturing process is assigned to other companies or other manufacturing plants, the manufacturer
is to submit the documents for identification system for its traceability.
303. Approval tests
1. Selection of test samples
(1) The test samples used for the approval test are to be selected, in the presence of the Surveyor, as a rule, from the steel tubes and pipes with the same conditions of material manufacturing process, fabrication method of tubes and pipes and heat treatment method.
(2) As a rule, the dimensions of the test sample are standardized according to the maximum manu- factured outer diameter, the maximum manufactured thickness and the closest 1/2 of these values. Furthermore, the number of test pieces is to be as deemed appropriate by the Society.
2. Test
(1) Items of the approval test are to be as given in Table 2.3.1 and are to be carried out in the presence of the Surveyor except otherwise specially provided.
(2) The test method and evaluation criteria are to be in accordance with the requirements in Pt 2,
Ch 1, Sec 4 of the Rules. However, where accordance with these requirements are difficult, de- cisions are left to the discretion of the Society.
304. Changes in the manufacturing process
In case changes occur in the approval content among manufacturing process of steel tubes and pipes which have been granted approval beforehand, such as those given in the following (1) through (8), the manufacturer is to submit the application of alteration to the Society together with the documents in response to the content of changes.
(1) Steel making process
(2) Ingot-making process
(3) Production process of tubes and pipes
(4) Limits of outer diameter and thickness
(5) Heat treatment process
(6) Chemical composition, added element, etc.
(7) Fabrication of steel tubes and pipes, heat treatment, etc. to outside manufacturers
(8) Use of raw materials manufactured by companies other than the ones verified in the approval tests (e.g. billet, rolled steel, etc.)
(9) Replace hydraulic test in product inspection with non-destructive test
305. Dealing after approval
Steel tubes and pipes which conform to the requirements in this Section are to be dealt with as [in
Guidance for Approval of Manufacturing Process and Type Approval, Etc. 2015 21
Ch 2 Approval of Manufacturing Process Ch 2, Sec 3
approved case] in the requirements in Pt 2, Ch 1, 201. 3 (2) of the Rules, unless otherwise speci- fied by the Society.
Test items Steel tubes and pipes | Base metal test | High temperature characteristi cs test | Corrosion resistance test | |||||||||||
Chemical analysis | Microstructure | Tensile test | Charpy impact test | Bend test | Flattening test | Flaring test | Reverse flattening | U- shaped bend | Hydraulic test | High temp tensile test | Creep test | Corrosion test | ||
Steel tubes for boilers and heat exchangers | RSTH 33 ~ RSTH 52 | ○ | ○ | ○ | ○ | ○ | ○ | ○ | ○ | ○ | ○ | |||
Steel pipes for pressure piping | RST 138 ~ RST 424 | ○ | ○ | ○ | ○ | ○ | ○ | ○ | ○ | |||||
Steel pipes for low temp. service | RLP A ~ RLP 9 | ○ | ○ | ○ | ○ | ○ | ○ | ○ | ||||||
Stainless steel pipes | RSTS 304TP ~ RSTS 347TP | ○ | ○ | ○ | ○ | ○ | ○ | ○ | ○ | |||||
Headers | RB H-1 ~ RBH 6 | ○ | ○ | ○ | ○ | |||||||||
NOTES: 1. Approval tests for each steel tubes and pipes are to be performed for each test item indicated with a ○ mark in the Table. Moreover, the application of the flattening, flaring, reverse flattening and bending tests are to be in accordance with the requirements in Pt 2, Ch 1, Sec 4 of the Rules. Also, high tem- perature tensile test and creep test are not applicable to Grade 1 and Grade 2 of steel pipes for pressure piping. 2. The U-shaped bend test method for steel tubes for boilers and heat exchangers is to comply with the re- quirements in the KS D 3563. 3. Where steel pipes for pressure piping and low temperature service have passed the tests for higher grade material with the similar strength level, pipe production method, heat treatment method, etc., the tests for steel pipes with lower grade may be omitted when deemed appropriate by the Society. 4. Where other steel tubes and pipes than those of the preceding 3. have passed the tests for higher strength level with similar chemical composition (carbon steel or low alloy steel), pipe manufacturing process, heat treatment method, etc., the tests for those with lower strength level may be omitted, sub- ject to submission of their acceptable data (i,e. specification of chemical composition and heat treatment, etc.) to the Society. 5. The high temperature tensile test and creep test as specified in the Table are performed for the purpose of evaluating high temperature characteristics of steel tubes and pipes, and these tests may be omitted in case appropriate technical reports are available or in case Society deems the tests unnecessary. 6. Where the steel tubes and pipes are not specified in the Rules or the steel tubes and pipes are used in special applications, tests other than those indicated in the Table (e,g, tests for welded parts) or the sub- mission of reference data may be requested. Moreover, where low temperature toughness is considered necessary, the COD test is required. 7. Where the welded steel tubes and pipes are not specified in the Rules or the steel tubes and pipes are used in special applications, tests for weld joint other than those indicated in the Table are to be required. - Tensile test for butt weld joint - Flattening test - Charpy V-notch impact test (weld and HAZ) - Hardness test for butt weld joint - Micro and Macro test for butt weld joint - Non-destructive test for butt weld joint (RT and/or UT) | ||||||||||||||
Table 2.3.1
Approval Test Items for Steel Tubes and Pipes
。
22 Guidance for Approval of Manufacturing Process and Type Approval, Etc. 2015
Ch 2 Approval of Manufacturing Process Ch 2, Sec 4
