Double Block and Bleed Valve (DBB)

One of the methods to measure the rate of corrosion indirectly occurring in the pipe is by using sacrificial coupon technique, wherein pieces of metal with the same/ similar material as the pipe installed in order to experience the same corrosion process as experienced by the pipe. The corrosion rate is measured and read from the weight loss of the coupon installed during the period of time in the pipeline.
Feature: 3 "coupon strip is used to measure the rate of corrosion in small sized pipes while 6" coupon strip are for large size pipes. 3 "coupon is used to measure the rate of scaling in pipes of small size, 6" coupon in pipes of large size. Multiple disc ladder coupon and coupon strips are used to measure the corrosion rate in the flow line which consists of more than one phase (oil / gas, oil / water or oil / gas / water).
Function: To obtain corrosion rate data operators must periodically pull the plug, and the corrosion rate data will be obtained after the coupon is analyzed in the laboratory. Very effective to determine the type of corrosion that occurs in the pipes, to know the cause of corrosion and are often used in the selection of materials.