Mechanical Engineering Magazine

Engineers were excited by the prospect of nuclear power when this article was first published in 1958.

Before the first commercial nuclear power plant in the United States could begin operation, the facility was thoroughly inspected.

E.M. Parrish, Duquesne Light Company, Pittsburgh, Pa.

SHIPPINGPORT –
PRELIMINARY TESTING

The details of testing are best shown by a description of the reactor component cooling-water system test, since many conventional stations are provided with a similar system.

As is the case with all of the systems tests, this test was performed to prove the integrity of the entire system and to test the individual components in order to assure that the operation was as designed. The test of this system was divided into four sections, each section intended to cover one phase of the complete test.

In the first section, the expansion tank, component cooling-water pumps, cooler, and supply and return headers were completely filled with water and hydrostatically tested, using a hand pump. At the same time, the pressure was increased in order to test and set the relief valves. The level indicator and alarms on the expansion tank were tested and adjusted as necessary to provide for satisfactory operation.

In the second section of the test, a corrosion inhibitor was added to and thoroughly mixed with the system water. Following the initial addition of this inhibitor, the concentration was determined weekly for a 2-month period. Any change in the concentration of this inhibitor indicated a plating action, and the concentration was then reestablished by the addition of inhibitor to the system.

As each of the components in this system was installed, the piping loop from the supply header through the component to the return header was filled and hydrostatically tested as a part of the third section of the test. Included with the hydrostatic test was a test of any relief valves in the loop. Also, as a part of this section, the instrumentation and controls were observed for satisfactory operation, performance tests were made of the component cooling water pumps, and when all the individual cooling loops through the various components were complete, the flow through the individual components was adjusted to a predetermined value by setting the flow-control valves in all loops.

In the fourth and final section of the test, the cooling water conditions for each component served by the system, operating under normal plant conditions, were determined. During this section of the test the entire system was observed as a single unit and a heat balance obtained for the cooler.

The completion of these four sections of this one test established the satisfactory operation of the system. In a conventional power station by way of comparison, many of the same tests are made but on a less formalized basis. Normally, in the conventional power station, the system would be placed in service initially by the operators who would observe, generally, the cooling water flow, temperatures, and pressures, and would assure themselves that the system is operating satisfactorily. In most cases, no further test would be conducted unless there was some evidence of system malfunction. ME

LEGO

The now-ubiquitous plastic toy brick was first developed in post-World War II Denmark by the Lego Company. The initial toy set, called “automatic binding bricks,” were not wholly original: stacking wooden blocks had been around for some time, and the Lego brick system was based on an earlier English toy design. The first Lego bricks were made from cellulose acetate, a material that didn’t lend itself to locking together. After years of looking for a better material, Lego hit upon the use of a tough, impact-resistant polymer called acrylonitrile butadiene styrene, and the new Lego system was patented in January 1958. Today, Lego has branched out into many types of toys, including programmable robots.