In the early 1960s, industrial users of turbomachinery began to experiment with the use of these sensors for measuring vibration. Direct observation of the vibratory motion of a machine's shaft is desirable because most often, the shaft is the source of vibration in the machine. Previous to the introduction of the so-called "Bently probe," this shaft motion had to be indirectly inferred by measuring the vibration of the machine's casing. While machinery casing measurements can be valuable under certain conditions, machines that employ fluid bearings generally have damping and stiffness characteristics that do not adequately transmit shaft vibration to the machine's casing. Consequently, direct observation of the machine's shaft (rotor) was recognized as a more accurate method of assessing condition on such machines.
Bently found that many of the third-party monitoring systems used with the Bently transducer systems were not properly configured. After repeated challenges resolving problems caused by the third-party monitoring systems, Bently decided to manufacture his own monitoring devices. Bently included the ability to generate alarms if vibration levels were excessive, which could alert operators and turn off the machine if necessary. This allowed Bently Nevada to offer machinery protection systems, not just monitoring systems.
It introduced the 5000 monitoring series in 1965 which was produced through 1998. This was followed by the 1700 series introduced in 1973, the 9000 series started in 1975, the 3300 series in 1988, and 3500 series in 1995. As of May 2020, new generations of the 3500 are still sold.
The company opened an office in Ohio in 1965 and another in Louisiana in 1968. In 1969 it opened its first international office in the Netherlands. In the same year, the company had 150 employees. It shifted sales from primarily third-party representatives to in-house, factory-direct sales force. The company grew from 200 employees in 1970 to 1000 by 1979.
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The eddy-current proximity probes pioneered by Bently addressed this need. In 1970 the American Petroleum Institute designated the proximity probe as the measurement device for measuring acceptable shaft vibration during factory acceptance testing. It added this as a requirement to its standard for centrifugal compressors. Bently's pioneering design for shaft vibration measurement using proximity probes became the de facto industry standard for turbomachinery acceptance testing and machinery protection. The eddy-current proximity probe became the preferred method for assessing vibration and overall mechanical condition on large turbomachinery employing fluid bearings. Such machines and bearing types account for the vast majority of compressors, turbines, pumps, electric motors, generators, and other rotating equipment exceeding 1,000 HP, and can be found in abundance in most industrial plants. As a result, the primary focus of the company shifted from laboratory measurements to industrial measurements on rotating machinery.
The company continued to expand, making diagnostic instruments such as spectrum analyzers, tunable filters, and other signal conditioning and recording apparatus, in addition to its sensors and monitors. As time went by, it also became apparent that customers were in need of expertise to help interpret their vibration measurements. In response to this, the company expanded its service organization in the 1980s beyond instrument installation and repair to include a team of machinery diagnostic engineers, skilled in collecting and interpreting vibration signals to help customers identify and correct machinery malfunctions. By 2002, Bently Nevada Corporation had more than 10,000 active products in its catalog and more than 100 offices in 42 countries.
Rotating machinery research
In 1981, Bently branched out from his instrumentation manufacturing activities and established a pure research organization called Bently Rotordynamics Research Corporation (BRDRC or "Birdrock"). Its objective was to conduct rotordynamic research, furthering the knowledge of rotating machinery behavior, modeling techniques, and malfunction diagnostic methodologies. Its mission was considered complementary to Bently Nevada, with BRDRC focused on understanding how machinery behaved, and Bently Nevada focused on understanding and building instrumentation to measure machinery behavior.
BRDRC made a number of important contributions to the field of rotordynamics such as a better understanding of fluid-induced instabilities, advanced models for understanding shaft crack behavior, insight into rubbing malfunctions between stationary and rotating parts, and enhancement of the rotordynamic equations with a new variable lambda (λ) which denoted "the fluid circumferential average velocity ratio".
BRDRC also introduced several new data presentation formats, such as so-called "full" spectrum plots and "acceptance region" trend plots. Its research findings were published extensively in relevant technical journals, and the research that had practical commercial applications found its way into the Bently Nevada product line. Rotordynamic and machinery diagnostic expertise remains a core part of the Bently Nevada product line through its machinery diagnostics services organization.
Builds new facility
In 1978, Don Bently acquired the Buckeye Ranch which had previously been owned by the Dengberg family. They had built brick barns at Orchard and Buckeye Roads, known as Ferris Heights, that allowed them to breed sheep earlier in the year. Bently renamed the location Bently Science Park. In 2001, Bently Nevada built a new $30 million, 283,000 square feet (26,300 m2) headquarters on 26 acres (11 ha). Bricks from some of the sheep barns were incorporated into the façade of the new building.
Don Bently required the building to withstand an earthquake measuring 8 on the Richter scale, which is four times as severe as the earthquake that struck Izmit earthquake in August, 2001, leveling thousands of buildings and killing more than 40,000 people. The new location consolidated at one site manufacturing, design, development, marketing, and sales operations that had previously been located at eight different locations around Carson Valley.
