BS ISO 18762:2016 pdf download – Tubes of titanium and titanium alloys — Welded tubes for condensers and heat exchangers — Technical delivery conditions
1 Scope
This International Standard specifies requirements for the manufacture of welded tubes made from titanium or titanium alloys, for use in condensers and heat exchangers.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 6892–1, Metallic materials — Tensile testing — Part 1: Method of test at room temperature
ISO 8492, Metallic materials — Tube — Flattening test
ISO 8493, Metallic materials — Tube — Drift-expanding test
ISO 10474, Steel and steel products — Inspection documents
ISO 25902-1, Titanium pipes and tubes — Non-destructive testing — Part 1: Eddy-current examination
ISO 25902-2, Titanium pipes and tubes — Non-destructive testing — Part 2: Ultrasonic testing for the detection of longitudinal imperfections
ASTM E29, Practice for Using Significant Digits in test Data to Determine Conformance with Specifications
ASTM A370, Standard Test Methods and Definitions for Mechanical Testing of Steel Products
ASTM E120, Test methods for Chemical Analysis of Titanium and Titanium Alloys
ASTM E1409, Test method for determination of oxygen and nitrogen in titanium and titanium alloys by the inert gas fusion technique
ASTM E1447, Test method for determination of hydrogen in titanium and titanium alloys by the inert gas fusion thermal conductivity/ Infrared detection method
ASTM E1941, Standard Test Method for Determination of Carbon in Refractory and Reactive Metals and their Alloys by Combustion Analysis
3 Information to be supplied by the purchaser
3.1 General information
The purchase order shall include the following information:
a) quantity (e.g. total mass or total length of tube);
b) grade number;
c) outside diameter and wall thickness (minimum or average);
d) length and type of length (random or fixed lengths);
e) method of manufacture and finish;
f) non-destructive tests;
g) packaging;
h) inspection;
i) certification.
3.2 Options
A number of options are specified in this International Standard and these are listed below. In the event  that the purchaser does not indicate a wish to implement any of these options at the time of enquiry andorder, the tubes shall be supplied in accordance with the basic specification.
a) Restrictive chemistry (see 5.2).
b) Product analysis (see 5.2).
c) Special mechanical properties (see 5.3).
4 Manufacturing
The welded tube shall be made from flat-rolled strips by an automatic arc-welding, a laser welding process and other welding processes. Use of a filler material is not permitted. Butt-welds are absolutely forbidden.
After welding, the tubes shall be annealed at a temperature between 500 °C to 800 °C when agreed upon between the manufacturer and purchaser and so stated in the purchase order.
5 Requirements
5.1 General
When supplied in the delivery condition indicated in 4.1 and inspected in accordance with Clause 6, the tubes shall conform to the requirements of this International Standard.
5.2 Chemical composition
The titanium and titanium alloys shall conform to the chemical requirements prescribed in Table 1.
The elements listed in Table 1 are either intentional alloy additions or elements that are inherent to the manufacture of titanium sponge, ingot, or mill product.
The content of any element intentionally added to the heat during melting shall be reported.
When agreed upon between the producer and the purchaser and specified in the purchase order, other specific residual elements not listed in Table 1 may be added; their content shall be reported.
5.3 Tensile properties
The room temperature tensile properties of the tubes shall conform to the requirements prescribed in Table 2.
Mechanical properties for conditions other than those given in this table may be established by agreement between the manufacturer and the purchaser.
The weld shall be positioned on the 90° or 270° centreline during loading so as to be subjected to the maximum stress.BS ISO 18762 pdf download.