#501-15: Direct Expansion Test System

Hydrostatic Direct Expansion Volumetric Expansion Cylinder Test System

Manually Operated
Rated for test pressures in a range of 200-1400psi
Meets / Exceeds U.S. DOT requirements for accuracy & readability

Includes:

Air Operated Test Pump

(2) Calibrated Pressure Gauges

Reservoir Burette Tube

Steel Enamel Painted Cabinet

Written Instructional Manual

Calibration Certificates

The direct expansion test method is used primarily for testing of large vessels such as 1/2 ton or 1 ton Chlorine, Propane and Refrigerant Gas cylinders.

This type of test method consist of measuring the amount of water passed into a cylinder under pressure. Upon release of pressure, measuring the amount of water returned to the expansion measuring device (burette). It is necessary to allow for the compressibility of water and the volume of the cylinder under test to obtain a true volumetric expansion

There is no water jacket used. An accurate scale, capable of weighing the vessel filled with water, is required.

A calibrated cylinder is used to verify the accuracy of the equipment each day prior to testing. The calibrated cylinder should be made at your facility to insure correct compressibility factors. As an alternative a second pressure gauge (included) can be used in place of the calibrated cylinder upon written approval from PHMSA approvals.

Detailed test procedure for this test method is described in the CGA C-1 pamphlet. It is strongly suggested that this procedure be reviewed for those inteding to perform this type of test.