Pressure Control Valves
Pfeiffer Vacuum offers with Intellisys downstream pressure control products providing measurable process benefits through higher resolution, speed and reliability. These benefits are the direct result of two core functions embedded in all Intellisys control systems. First, a unique patented closed-loop motor control technology, which is a combination of hardware and software. This allows Intellisys control valves to be operated at high rates of speed and with extremely fine positional resolution. Second, based on these capabilities is an adaptive pressure control algorithm that yields near flawless pressure control performance over a wide range of system conditions without the need to “learn” proportional–integral–derivative (PID) parameters. Adding to the pressure control system benefits is a host of valve functions and features aimed at optimizing control performance and reliability. Features include the selection of direct, gear and ballscrew driven valves that do not rely on unreliable mechanical or optical switches to determine the valve stroke endpoints. Instead, hard stops that are sensed by the closed-loop motor position feedback signals serve as the open and closed indicators. Additionally, all Intellisys control valves, regardless of type, have been designed for controllability and conductance. Throttle plates and actuation mechanisms enable the behavior and reliable performance of the downstream pressure control system.
Every complete downstream pressure control system design incorporates three components including a throttle valve, valve controller and vacuum gauge. Pfeiffer Vacuum has products available in all of these categories. The selection of throttling products includes families of butterfly and pendulum valves. The choice of valve depends on the intended application, but each is available in a wide range of sizes and flange types with many optional functions and features.
Adaptive pressure controllers (APC) are available for each type of valve or valve drive, and come in two styles. First, the controller integrated directly on the valve provides a compact all-in-one solution. Second, the stand-alone buried box controller connected to the valve by a cable is ideal for applications where the environment is not suitable for the controller’s circuit boards. Regardless of type, all Intellisys controllers have an RS-232 communications interface and optional RS-485, Analog/TTL, DeviceNet and EtherCat communications available.
Capacitance diaphragm gauges (CDG) feature an ultra-stable ceramic diaphragm and advanced digital circuitry in unheated and heated models. They enable precise pressure measurement independent of type of gas. The gauges are available in all common vacuum ranges and can be supplied with most popular vacuum connections.