Look closely at the key items in Table II. An analyzer is a field instrument; therefore, the first item under Instrument and Electrical should be carefully worded to describe the proposed system. The words “analyzer system” are important to convey the idea that the project involves more than a single instrument and includes the analyzer or analytical sensor, a sample handling system (SHS) and additional equipment and devices. This document is probably not the appropriate one for these details, but it is important to plant the notion that analyzers tend to be more complex (and expensive!) than conventional field instruments.
As a field instrument, an analyzer system naturally requires local wiring, home-run signal cable, low-voltage power wiring, rack-room wiring and control room (DCS, PLC, etc.) work. These items constitute the probable minimum hardware scope for a process analyzer project.
Non-hardware capital items include commissioning, construction management and rental equipment. Among the expense items, startup is the minimum (in addition to engineering).
But the scope of most process analyzer projects goes beyond these “minimums.” An analyzer is a “field instrument,” which puts it in the same category as temperature, pressure, flow and level transmitters, all of which measure extensive properties. But an analyzer measures chemical composition, which is an “intensive property” of the manufacturing process at a given point, making it inherently more complicated than its conventional counterparts, and making system project scopes longer and affecting more scope line items.
With an active client, the analyzer project engineer should not be alone in the effort to develop an acceptable detailed scope. Each project should have safety, environmental and utility reviews early in scope development and feasibility study. These reviews usually require a face-to-face meeting among at least some of the project team members and have a set format or form. These reviews often clarify, suggest or require the addition of many of the scope items. If allowed under the review procedure, these meetings are an excellent opportunity for the analyzer project engineer to ask explicitly about these scope items and listen to client concerns not previously raised.
Most line items in Table II will have direct labor and direct material costs, reflected on the estimate page of the project approval package. Table III is a list of typical red-lined drawings that would accompany the project approval scope and that would clarify and amplify the verbal content of the written scope for all members of the project team.
Typical Redlined Drawings and Sketches for Analyzer Project Scope Development
- Piping and instrument drawing (P&ID)
- Instrument loop sheet
- Instrument location drawing
As Needed/Usually Helpful
- Process flow drawing (PFD), may be called energy and material balance
- Sample handling system (SHS) drawing or sketch
- Analyzer system elevation drawing or sketch
The analyzer system project engineer may also wish to use drawings from other disciplines such as site plans and elevations, piping isometrics and vessel drawings to clarify scope.
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