White Papers: Controls and Automation

Hot Water Project: Phase 4

As we noted in the last hot water project blog, the customer noted that the steam pressure varied and the steam control valve position did not necessarily represent the steam flow to the heater. Let’s get the steam under control. We tell the customer that the addition of instrumentation to the steam lines will cost Read more…

Hot Water Project: Phase 3

As we noted in the last blog, the customer noted that the water pressure varied and the water control valve position did not necessarily represent the flow through the heater. The customer has indicated that they would be able to release some additional funds for process instrumentation. At this time a flow measurement of the Read more…

Hot Water Project: Phase 2

As we noted in the last blog, the customer has told you he is unhappy with the temperature control of the process water. After signing a telephone book of nondisclosure agreements the customer has offered additional information regarding his process. During the past months of operation they have been able to characterize the efficiency of Read more…

Hot Water Project, Phase 1

One of the more common projects is to heat water (or some other liquid) from a random cold temperature to a desired working temperature. The inevitable discussion occurs with your boss or the customer regarding the usual items – schedule, scope and costs. If you are lucky, the customer has properly identified the scope of Read more…

Participation of Multiple Elements

There are times in larger processes when many like-type devices must be used in parallel to achieve the desired through-put to adequately supply the process. Either the applicable equipment technology has not evolved to provide the through-put or the equipment has reached its technological limits and cannot be manufactured or increased in size without decreasing Read more…

Extend Valve Control Flow Range

Extend the valve control flow range with staged valves A single valve may not have the resolution needed to adequately control the process. Another example is while dealing with large flows requiring precise control over the whole flow range. Providing a single valve with the required Cv (effective valve flow coefficient) characteristics may be extremely Read more…

Control the Flow

Control the flow – select an appropriate valve trim Normally when the process or mechanical engineer designs the process and selects the individual components, they may not necessarily select the proper trim characteristics that would properly complement the control design. A valve and trim selection training course could cover several days and will not be Read more…

Pumps and Flow Problems

Pumps will perform as designed and last a long time as long as we respect their limitations and treat them well. There are several parameters that the mechanical or process engineer and control designer need to understand and respect. These parameters include: 1. NPSHRequired and NPSHAvailable 2. Minimum Stable Flow 3. Pump Curves 4. Best Read more…

Starting a new control project

It is interesting to note that control projects generally fall into two categories: 1. A new control process or 2. Enhance or copy an existing control process. Tackling either of these options need to follow a similar approach. Sometimes the individuals tasked with these projects feel that they can worry about the details later. “I’ll Read more…