The Simple Pressure Vessels (Safety) Regulations 1991

PART 4 DEFINITIONS AND SYMBOLS

Definitions

13.  In this Schedule–

(a) “minimum working temperature” means the lowest stabilised temperature in the wall of the vessel under normal conditions of use;

(b) “inspection slip” means the document by which the producer of the materials certifies that the materials delivered to the manufacturer meet the requirements set by the manufacturer, and in which the producer sets out the results of the routine inspection tests carried out during the production of those materials (or of materials produced by the same process but not being the materials delivered to the manufacturer) in particular as to their chemical composition and mechanical properties;

(c) “maximum working temperature” means the highest stabilised temperature in the wall of the vessel under normal conditions of use;

(d) “maximum working pressure” means the maximum gauge pressure which may be exerted under normal conditions of use; and

(e) “yield strength at the maximum working temperature” means:

• the upper yield point for a material with both a lower and an upper yield point; or

• the proof stress at 0.2%; or

• the proof stress at 1.0% in the case of non-alloy aluminium.

Symbols

14.  In this Schedule–

(a) “A” means the percentage elongation after rupture (L N S where L is the gauge length expressed in millimetres and S is the cross-sectional area of the test section expressed in square millimetres; and

(b) “A_80mm” means the percentage elongation after rupture (L_o = 80mm).