BS EN 12266-1:2012 pdf download
BS EN 12266-1:2012 pdf download.Industrial valves – Testing of metallic valves Part 1: Pressure Tests, test procedures and acceptance criteria一Mandatory requirements.
3.4
test fluid temperature
temperature of the test fluid, 5C and S 40 C
3.5
DPI. NPS
alphanumeric designation of size that Is common (or components used in a plpcg system, used for reference purposes, comprising the letters tN or NPS” followed or preceded by a dimensionless number indwectty related to the pflysical size of the bore or outside diameter of the end connections
Note 1 to entsy The number folovflng tN or NPW does not represent a measurable value end should not be used for calculation purposes except where specified In a product standard.
3.6
P14 or Class
alphanumeric designation for pressure-temperature rating that is common for components used in a piping system.
used for reference purposes, comprising the letters PN or Class’ followed by a dimensionless number indirectly
related to the pressure retaining capability as a (unction of temperature of the component
3.7
cold working pressure
CWP
maximum fluid pressure assigned to a valve for operation at a fluid temperature of —20 DC to 38 °C
Note 1 to entry Valve pressure-temperature ratings are specitied In product standards by reference to PN or Class designations
3.8
double blockand.blnd valve
valve with two separate closure seating surfaces that, when in the closed position, block the flow from both ends when the cavity between the two seating surfaces Is vented through a bleed connection between the body cavity and the outside environment
4 Test requirements
Test procedures and acceptance critena shall be as given in Table 1 and Annex A.
a) Shell strength lest PlO is mandatory for every valve except when a statistical sampling is permitted.
b) Shell tightness test P11 is mandatory for every valve except when a statistical sampling is accepted.
c) Seat tightness test P12 is mandatory for every isolating and check valve except when a statistical sampling is accepted,
The seat tightness test for control valves shall be Ii accordance with EN 1349.
A.1 General requirements
A1.1 Purpose
These general requirements shall be applied to all the test procedures detailed in this annex.
Safety aspects of valve testing are not covered In this European Standard
NOTE Users of the European Standard should analyse the hazard resulting from the pressure and faIre proper safety
precautions
A.1.2 Test equipment
The test equipment shall be of such a design that it does not subject the valve to externally applied loads which may affect the results of the test.
NOTE The test equipment can apply external loads sufficient to react to the forces resulting from the test pressure,
When using test equipment and procedures different to that detailed In this European Standard, the manufacturer shall be able to demonstrate the equevalence of such test procedures and acceptance criteria with the requirements 01 this European Standard.
A.1.3 Measuring equipment
The measuring equipment shall be capable of measuring fluid pressure with an accuracy of ±5 % of the required
test pressure.
A.1.4 Painted, coated or lined valves
Before the shell strength test, reference PlO. and the shell tightness test, reference P11 valves shall not be painted externally or otherwise coated with materials capable of sealing against leakage from external surfaces of the shell
Valves with liners, internal lwiings or coatings forming a design feature of the valve may be tested with the liner. after lining or coating.
Attention shall be given that the liners, internal linings or coatings are not damaged by the test procedure NOTE If tests In the presence of a representatrve of the purchaser are specified, painted or coaled valves from stock may
be retested without removal of painting or coating.
A.1.5 Test fluid
The test fluid to be used shall be:
either a liquid (water which may contain a corrosion inhibitor, or any other suitable liquid having a viscosity not greater than water);
— a gas (air or other suitable gas).
