Temperature Monitoring Goes to Extremes
As part of its work on the West-to-East Gas Pipeline Project (WEPP) in China, Changzhou Huali Hydraulic Lubrication Equipment Co. (HHLEC) had to find a way to meet the challenges caused by an altitude of 9,842 feet (3000 meters), where temperatures reach -40º F (-40º C). If the temperature exceeds the limit, the lube oil quality is impacted. If the temperature is too high, the lube oil may damage the compressor. HHLEC recommended adding temperature sensors and transmitters to monitor the temperature in the system. If oil temperature exceeds the limit, an alarm will be sent by the transmitter.
However, not all temperature measurement equipment is suited for this type of environment. “I used some locally manufactured sensors and they will break in a harsh environment,” reported Mr. Yu, chief engineer, HHLEC, Ltd. Furthermore, LCD meters were needed that could withstand the cold. “I needed an LCD meter which can stand -40 degree C as our equipment is installed in the desert and high altitude which will expose the equipment to low temperature,” stated Mr. Za, design engineer, HHLEC, Ltd.
Stability saves on maintenance
But what about the need to control maintenance costs? Sensor inefficiency and drift can be very expensive since it creates a need for recalibration by a service technician and can raise maintenance costs considerably. “It is a very high cost if we travel to site for maintenance of the measurement products in our lubrication equipment,” stated Mr. Wu, maintenance engineer, HHLEC, Ltd. The answer was using transmitter-sensor matching and calibration with products from a single manufacturer designed to work together in unison.
Transmitter-sensor matching is achieved by utilizing the Callendar-Van Dusen (CVD) equation and entering the CVD constants into the transmitter thus matching the transmitter to that specific sensor, which provides the outstanding accuracy. The calculations indicated the best match was a Rosemount 3144P Transmitter and Rosemount 0065 Sensor that offered both high accuracy and long-term stability, even in the harsh environment. HHLEC installed and commissioned 20 units of the Rosemount 3144P Transmitter and Rosemount 0065 Sensor.
The Rosemount 3144P Transmitter is designed for harsh environmental factors that can make other transmitters susceptible to failure. The Rosemount 3144P ensures calibration integrity and improves measurement point accuracy. A Rosemount 0065 Sensor with high standard welding construction and manufacturing process will provide long-term stability and life.
The solution of using Rosemount products from Emerson Process Management fulfilled GE’s needs for reliability in a harsh environment and also brought long-term stability. Safety levels were also improved with the Rosemount 3144P’s SIL2 certification. Maintenance costs were lowered as well, enabling the station to save 30% annually on maintenance, with needing fewer sensor replacements and fewer visits by service technicians.
GE extended its contract with HHLEC to work on other parts of the WEPP project because of the positive experience and outcome. Since the start of 2014, an additional 160 Rosemount transmitters and sensors have already been purchased for the project.
For more information about Emerson and the Rosemount brand of products visit Rosemount.com/temperature.