The damper and valve electro-hydraulic actuator systems from BLAC INC. come with two different arrangements. These arrangements are self-contained and what BLAC INC. calls the split unit type.

Self-contained units incorporate all the hydraulics and the control system for the actuator into one assembly. These applications are generally used on smaller valve and damper applications.

Valves can range in virtually any size and can be operated with self-contained actuator systems such as the BLAC INC. Pantera series, depending on speed and certain functions that may be required.

For dampers, virtually any louver or center shaft dampers can be operated with Pantera electro-hydraulic systems.

Split unit actuator systems from BLAC INC. have two separate entities with one being the hydraulic power and control unit and the other being the drive actuator assembly that is mounted to the valve or to the damper.

The split unit actuators are generally incorporated into larger applications or where physical interference limits access.

These applications typically have the valves in difficult locations to access. For the Power Generation marketplace, we also provide high speed controls or emergency trip functions with the split unit formats that are sometimes not available with the self-contained systems.

Generally, split units can also be utilized where there is a combination of large thrust/torque, emergency trip (ESD) functions and when higher speeds are required. Large louver or door sheet type dampers also utilize the split unit designs.

The self-contained and the split unit actuator assemblies are arranged differently, but for the Power Generation and Pipeline industries, the actuator systems have the same performance capabilities.

The actuators are provided with accuracies below 0.1% in variable speed modulating format and in on/off jog movements at 1 to 100 seconds full stroke.

They feature an optional emergency trip to fail-safe position through accumulators, springs or UPS, and can be provided with virtually any torque or linear output range of 1000 lbf (4,448 N) to 80,000 lbf (355,858 N) of output force.

The output torque for rotary applications is from 600 lb-ft (813 N-m) to 24,000 lb-ft (32,540 N-m) with larger systems available per request.

All area classifications for NEC or ATEX explosion proofing can be provided.

***See our PANTERA Series Self-Contained and Split Unit Electro-Hydraulic Actuators***

Boiler valves are actuated by BLAC INC. to provide extreme accuracy of control for the boiler.

In most boilers, the pneumatic actuated valves allow 3 to 4 percent fluctuation as that is the real world accuracy of most pneumatic positioners controlling the valves. This is sloppy and costs so much more in energy to the boiler efficiency than is justified with today’s costs of operation and fuel. 

Therefore, accuracy of control pays back to the owner-operator of a boiler very quickly by placing the boiler operation at maximum performance and keeping it there with good valve and damper actuation.

Startup valves, boiler drum level control, damper controls for all louver style dampers, wall fire control dampers – all can be controlled within 0.1% of the setpoint. This difference in control can mean US$100,000s difference per year in improved output on a small boiler, and US$Millions in return on larger boilers. 

Efficiency is determined in many ways, but the heat rate of a boiler is the only true measurement. If the heat rate alone can be improved by 3% on a boiler just by getting better actuation performance, it means a lot of financial impact to the plant economics. 

Contact BLAC INC. for more information.

BLAC INC. retrofits hydraulic control systems for steam turbines of any size to modern high performance electro-hydraulic (EH) systems. The conversions are provided on low pressure control oil systems on steam turbines that have not been previously modified, or on high pressure EH systems that are out of date. 

Turbine control systems provide all aspects of the system, including hydraulic power unit, hydraulic fluid conditioning system, hydraulic controls and PLC or analog electronic controls. The applications for the steam turbines valves are governor control, main steam stop, main steam stop bypass, intercept, and reheat bypass valves.

Additional miscellaneous equipment is also provided to complete the retrofit, including P&ID modifications for dismantling, new P&ID modifications and full engineering retrofit for mechanical systems. Magnetic speed pickups, 60 tooth wheels, LVDTs, needed covers and blanking plates, and engineered products to isolate old hydraulic control systems are offered.

Other off turbine applications are provided for the turbine bypass systems and turbine startup valves. These systems are provided in self-contained or in split unit hydraulic actuator format. Safety and functionality is of the utmost goal in providing this equipment to the industry.

BLAC INC. provides upgrade and repair capability for the equipment from other manufacturers for the above applications. This includes the hydraulic power unit, hydraulic controls and the PLC control systems. 

***See our TURNAROUND AND MAINTENANCE SERVICES page for details***

Steam turbines in power stations have several valves involved in their control and startup. The valves around the steam turbine all can be operated with BLAC INC. turbine actuator systems (see specific applications that follow).

BLAC INC. also supplies LVDTs, Speed Pickups, Brackets and Hardware, and PLC control/monitoring systems for the valves, hydraulic control systems and hydraulic power units.

Hydraulic Power Units – For the following applications in the table, we provide hydraulic power units with circulation systems, fluid treatment systems and fluid cooling systems. All have options for continuous fluid monitoring systems incorporated into the design.

Hydraulic Controls – For the following applications in the table, we offer hydraulic control manifolds, accumulators and electronic controllers that fit different size valves but provide high speed, high accuracy and emergency trip control functions. All valves can be provided with single trip, double trip or triple trip solenoid valves.

Our gas turbine actuator systems are available for new equipment installations or as retrofit modifications on your current GT systems.

BLAC INC. provides high speed, accurate and reliable actuators for fuel gas control and isolation valves, fuel bypass and isolation valves, and for inlet guide vane control drives. The fuel gas and stator vane actuators and controls are generally operated from a common Hydraulic Power Unit (HPU).  Both systems are available as self-contained units also.

Also available are door or louver type damper drives and controls for the GT diverter dampers with an HRSG as shown in the photo. These units have a combined seal air skid with redundant air blowers. Long term operational guarantee for these systems is available as well as rebuilding services.

BLAC INC. provides upgrade and repair capability for the equipment from other manufacturers for the above applications. This includes the hydraulic power unit, hydraulic controls and the PLC control systems. 

***See our TURNAROUND AND MAINTENANCE SERVICES page for details***

The photo shows a BLAC INC. Gas Turbine Heat Recovery Steam Generator (HRSG) Diverter Damper system.

Contact BLAC INC. for information on how we can provide for your application.

BLAC INC. has utilized the smallest of its Pantera Series self-contained linear actuators for a power plant pressure control application.

The Pantera electro-hydraulic actuator in this case was designed for modulating service to control the sootblower header pressure downstream of the pressure regulator valve.

The requirements have the pressure setpoint operator adjustable at the BLAC INC. electronics enclosure for automatic pressure control. The downstream pressure transmitter signal is used as the process variable in the control loop.

This Pantera system uses a variable frequency drive (VFD) to compare the setpoint with the process variable to obtain the position error. The difference in error is corrected with use of the reversing motor at the hydraulic power and control unit (HPCU).

The HPCU motor drives the hydraulic fluid one direction or the other to cause a position correction for the PRV. The BLAC INC. electronics also provide local operator jog capabilities to move the PRV.

Both the setpoint and the pressure are displayed at the BLAC INC. electronics enclosure for local operation.

Shown for this application is the Pantera self-contained HPCU with controller enclosure and remote actuator assembly with hose connections.