Pipeline Safety Stakeholder Communications

Overview:

Most pipelines are operated remotely from a centrally located control center. These Remote Control Centers allow for the efficient operation of either a single or a number of the operator’s different pipeline systems from a single location. The operators of the pipeline can control pump starts/stops, valve opening/closing, monitor product movements, monitor leak detection systems, conduct training operations, and otherwise manage staff from a single operations center.

Remote Control Center Advantages

Remote control centers provide operators complete operational information of the pipeline system in one location. Typical information includes:

• Pipeline mimic / displays. The complete pipeline can be mimicked to provide operator instantaneous visual feedback on the status of any portion of the pipeline; pumps, valve, tanks, etc. These visual schematics include overviews of the entire pipeline system or systems and drill-down screens that take the viewer to an individual location or piece of equipment
• Pump, compressor, and other equipment status. Equipment operation can be displayed with status (On/Off) and other critical parameters associated with a piece of equipment such as flow, discharge pressure, vibration, case temperature, etc.
• Valve status. Valve information can be displayed with valve positions (open/throttle/closed) depicted
• Alarms and other operational indications are immediately available for operator response where complete system status is known and, in many cases, can be displayed. These can alert the controller to an unusual or abnormal operating situation or remind the controller about upcoming operating changes that need to be initiated
• Trending history and other analytical tools and graphical aids are available to assist personnel in their decision-making under routine, abnormal, and emergency conditions.

In addition to the display capabilities, a Remote Control Center provides a centralized response-and-control base of operations to facilitate the coordination and response of abnormal or emergency situations. It also provides a centralized base of operations for ongoing maintenance and other field activities occurring on the pipeline system.

Remote Control Center Operation

Pipeline systems are typically operated from computerized control centers, which coordinate operations throughout the system. To allow for this coordinated control, data from the entire pipeline system must be transferred from the field locations to the central control station. This is accomplished by use of:

• Field instruments. Pipeline operating parameters are monitored on a continuing basis by field instruments local to the pipeline. The data from these instruments must be retrieved and assembled for transfer to the Remote Control Center. This is accomplished by Remote Terminal Units (RTU).
• Remote terminal units (RTU) are the collection point for the field devices providing the information to the Remote Control Center. This will include pipeline instrumentation such as flow, pressure, temperature, and density, tank levels, and other information such as pump operating/stopped, valve open/closed, etc. Analog data such as pressure, temperature, density and flow must be digitized for ease of transmission to the Remote Control Center. This is accomplished by the RTU. The data from the RTU is transmitted to the Remote Control Center on a pre-determined frequency Normal data transmission may be based on regular transmissions such as 5 or 15 second intervals or when the data has changed from the previous transmitted data, e.g. change of position of a valve.
• Telephone and satellite. The data is transmitted from the RTU to the Remote Control Center via dedicated telephone lines or via satellite communications.
• Supervisory control and data acquisition (SCADA) systems receive the data from the satellite or telephone connection. The SCADA is a computer based operational control system that receives the data, records the data, analyzes the data, and displays it to the operator. Based on analysis of the data, the SCADA provides alarms to the operator.
• The SCADA is also a control point for pipeline operation. The SCADA will receive input from the operator to control the pipeline by starting or stopping pumps, opening or closing valves, diverting flow, etc. This control information is transferred in the reverse path from the SCADA to the RTU via telephone or satellite communications and then to the final control device.

Remote Control Center Staffing

The flow of product in the pipeline is typically a 24-hour-a-day, 7-day-a-week operation. The Remote Control Centers are staffed continuously in order to monitor and maintain this round-the-clock operation. Due to the data being transmitted from potentially many miles away, the operator oftentimes must respond to the alarm and direct a corresponding response from the Remote Control Center based on the information depicted on the display provided by the SCADA; however, in other cases, decisions are made in conjunction with personnel located in the field at the affected location(s).

Date of Revision: 12012011