DIN 17178:1986-05

1 Field of application
2 Concept
3 Classification into grades
4 Designation and ordering
5 Requirements
      5.1 Manufacturing process
      5.2 As delivered condition
      5.3 Chemical composition
      5.4 Mechanical properties
      5.5 Weldability
      5.6 Heat treatment and further processing
      5.7 Appearance of surface and weld
      5.8 Soundness
      5.9 Non-destructive testing
      5.10 Dimensions, masses per unit length and
             permissible deviations
6 Testing and materials testing certificates
      6.1 General
      6.2 Test site
      6.3 Scope of test programme
      6.4 Sampling and sample preparation
      6.5 Test procedure
      6.6 Retests
      6.7 Materials testing certificates
7 Marking
8 Complaints

Applies to welded circular tubes subject to special requirements and made from the fine grain structural steels listed in Table 1. These tubes are intended to be used on the basis of a 100% utilization of the permissible design stress in the weld. They are predominantly used in the construction of pressure vessels, chemical plant, pipework and for general mechanical engineering purposes. They are designed for operating temperatures not exceeding 400degreeC and, in the as delivered condition (see sub-clause 5.2) normally exhibit a minimum yield strength of between 255 and 460 N/mm2, as given for the lowest wall thickness range in Table 3.