The model AT-1000 freeze valve has two operating positions,a full flow position for testing and/or purging and a restricted flow position for testing. A liquid-phase sample is allowed to flow through the valve under the full flow condition to chill the valve housing by cooling effect of the change from a liquid to a gaseous state. A spring loaded valve stem and cam action actuator provide instantaneous switching from the full flow conditions to the testing condition. The valve and test method are particularly suited for use outside laboratory. If the freeze time indicates that the product may cause freezing, faulty operation of pressure reducing regulators may occur and thus an anti-freeze agent may then be added, if desired.
If the LPG under test already contains an antifreeze agent, the time taken for the test AT-1000 freeze valve to freeze is not necessarily a function of dryness, but may provide an indication of the tendency of the LPG to cause freezing in pressure-reducing regulators in service conditions.
The AT-1000 LPG Freeze valve is designed to meet the ASTM D-2713, JLPGA-S-10T and ISO 13758 Test Standards.
