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Knowledge-Based Robust Piping Design (PDF)
Constructability's Role in Project Execution (PDF)
FEED - A Definition
Going With the Flow: Reaching Your Final Destination Using Flowsheets

HPAC Engineering

<<Over the last three or four years, about half of the powerhouses my firm worked in were using out-of-date flow diagrams. Even a few complete manufacturing plants had outdated piping schematics for the overall facility. When we start an engineering project at such facilities, we end up spending days--even weeks--getting the documents up-to-date. >>

Workflow Challenges During Front-End Engineering (PDF)
Pipeline Platelets
SCADA Primer (PDF)
Pressure Drop Theory

Daxesoft Ltd.

<<This page describes in detail which factors need to be considered when calculating pressure drops through pipe systems, their effects on fluid flow and conditions at the pump inlet, and how Pipe Flow 3D can help with the calculations.>>

Flow-Induced Vibration and Noise

Southwest Research Institute

<<With certain flow conditions, piping systems will develop high levels of noise and vibration that can damage the pipes and related systems such as tube bundles, side cavities, and bluff or tapered bodies in flow streams. Pipe damage compromises plant safety, forces shutdowns, increases maintenance, and reduces efficiency and capacity. >>

Surges in a Piping System [PDF]

Geoffrey Stone, Design Detail & Development

<<This article raises a number of issues in respect of the risks you may be exposed to from the requirements to consider the pressure transients in a piping system design. The risks not only relate to physical damage but the consequential risks that arise from such damage whether it is contractual or loss of use.>>

Piping Surge Solutions [PDF]

Geoffrey Stone, Design Detail & Development

<<Pressure surges occur in all fluid pipeline systems. There arise two types of damage from the surge phenomenon, fatigue and catastrophic failure. This paper addresses this phenomenon from the viewpoint of the available solutions rather than the mathematics and modelling involved in determining the quantum of the surge pressure.>>

Process Design Team: Thinking Outside the Box

pipingdesigners.com

<<Designing the modern process plant is not a simple task. The typical process plant is a long, costly and complex effort. The total project effort is normally made up of a large diverse group of people from many disciplines. A sophisticated firm with a highly trained and experienced staff normally accomplishes the actual hands-on engineering and design work. Members of the overall project group will also include the client's team. There will be the client's project management, the client's plant operations, and the client's maintenance group. There are also the process licensors (if applicable), vendors, and suppliers. Then there are the service organizations, sub-contractors, and the construction management team. For most process plants, there will also be present, the influence of local, state, and federal (or national) representatives. Each of these entities or groups will contribute their own specific rules as codes, standards, specifications, regulations, and practices. These rules are there for a purpose and for the most part that purpose is safety. These rules are meant to be followed. At times' engineers and designers may feel "boxed-in" by what seems to be conflicting criteria. It is sometimes difficult, but as we all know not impossible to comply with the rules. There may be cases however, where a design team has successfully complied with all the specific written project criteria along with all the rules and still ended up with a poorly designed plant. Good design is also important to a project's success. Good plant design is not just the simple interpretation of the applicable written criteria. Good design includes how the criteria are applied. While it is true that the design team must know and properly apply all the applicable codes, standards, specifications, regulations, and practices, they must also know what constitutes good design. 'Thinking outside the box' is a phrase that is popular today. The box, in this case is these rigid codes and standards. The design team must be able to get outside the box and think about those issues that are not stated in the pure terms of the written word of the rules. These issues relate to; plant purpose and functionality, cost verses worth, schedule, safety, constructability, operations, maintenance, and aesthetics. Every person on the design team needs to broaden their thinking. They need to include all aspects of the total project. They need to 'think outside the box.' >>

Process Piping and the Codes

PM Engineer

<<In closing, the ASME B 31.3 is the only accepted code that exists for process piping systems. It is directly required by law in Canada and indirectly in the U.S. by means of OSHA process safety requirements and insurance mandates. However, the fact that the code is required should not be the only reason to compel users to follow it. If followed, it is an excellent means to insure the safe, reliable installation of process piping, as evidenced by the excellent record that exists in chemical plants and petroleum refineries throughout North America. >>

White Paper - Stainless Steel

Stainless Plate Products, Inc.

<<Stainless steels are primarily used when corrosion or oxidation is a problem. The function that they perform cannot be duplicated by other materials for their cost. Over 50 years ago, it was discovered that a minimum of 12% chromium would impart corrosion and oxidation resistance to steel. Hence the definition “Stainless Steels”, are those ferrous alloys that contain a minimum of 12% chromium for corrosion resistance. This development was the start of a family of alloys which has enabled the advancement and growth of chemical processing and power generating systems upon which our technological society is based. Subsequently several important sub-categories of stainless steels have been developed. The sub-categories are austenitic, martensitic, ferritic, duplex, precipitation hardening and super alloys.>>

The Accuracy of Calculations

ABZ, Inc.

<<With the widespread adoption of engineering software and computerized design processes, it is commonly thought that engineering calculations are very accurate. However, while engineering software can eliminate mathematical errors and perform calculations with greater speed than hand calculations, there are many factors that must be acknowledged which can result in the calculated values being substantially different from actual measurements. This article will discuss some of the factors that can make calculations vary from measured results, including factors related to system construction as well as to system modeling. These factors can then be considered during system design to ensure that the design will meet all necessary requirements. In addition, consideration of these factors is also prudent when troubleshooting existing systems to avoid drawing unwarranted or incorrect conclusions.>>

Dynamic Susceptibility Method for Piping Vibration

SST Systems, Inc.

<<When addressing vibration issues, the piping designer does not have the specific requirements, nor the analytical tools and technical references typically available for other plant equipment such as rotating machinery. Typically, piping vibration problems only become apparent at the time of commissioning and early operation, after a fatigue failure or degradation of pipe supports. Discovery of a problem is then followed by an ad hoc effort to assess, diagnose and correct as required.>>

A Piping Tutorial

Engineering Design & Analysis Ltd.

<<Pipe is a pressure tight cylinder used to convey a fluid or to transmit a fluid pressure, ordinarily designated pipe in applicable material specifications. Materials designated tube or tubing in the specifications are treated as pipe when intended for pressure service. Piping is an assembly of piping components used to convey, distribute, mix, separate, discharge, meter, control or snub fluid flows. Piping also includes pipe-supporting elements but does not include support structures, such as building frames, bents, foundations, or any equipment excluded from Code definitions. Piping components are mechanical elements suitable for joining or assembly into pressure-tight fluid-containing piping systems. Components include pipe, tubing, fittings, flanges, gaskets, bolting, valves and devices such as expansion joints, flexible joints, pressure hoses, traps, strainers, in-line portions of instruments and separators. Piping is typically round. >>

Overview of Process Plant Piping System Design

ASME

Adjusting the Boiler Code

Mechanical Engineering Magazine

<<Technological advances have made it possible to reduce the material design factor in the ASME Boiler and Pressure Vessel Code. >>

Common Assumptions Made By Other Fluid Flow Programs Versus The DFS Approach

ABZ, Incorporated

<<Many fluid flow analysis programs make questionable or clearly incorrect assumptions when solving problems. Most of these assumptions remain undocumented, or documented where they will not be read by the average users. When questioned, most of these companies will downplay any of these issues by stating that they just don't matter. We think you should decide for yourself. Below are some of the common assumptions that can result in significant errors in calculated results, as well as a simple problem for each assumption that one can use to demonstrate the error. In no case has ABZ provided the worst case situation in an attempt to bias the results. All of these errors can be worse or better, depending on the specific details of the problem being analyzed. >>

Positive Displacement Pump Vibration

Engineering Dynamics Incorporated

Dynamic Design Considerations When Modernising a Pipeline Compressor Station

Engineering Dynamics Incorporated

Analysis of Vibration Failure Problems in Reciprocating Triplex Pumps for Oil Pipelines

Engineering Dynamics Incorporated

Piping Vibration and Stress

Engineering Dynamics Incorporated

Pipeline Pump Vibration and Failure

Engineering Dynamics Incorporated

Evaluating Dynamic Stresses of a Pipeline (PDF Document)

K.T. Truong

<<Piping vibration is as much of a concern to utility owners and operators as to federal regulatory bodies. Many programs have been developed to assure reliability and plant safety with respect to vibration while minimizing cost and delay during plant start-up. The acceptance of a piping system vibration is determined by the maximum vibratory stress in the pipe [...]. This present approach also offers a basic understanding to solve quickly vibration problem when and where the computer software is not accessible.>>

Piping Vibration

Carmagen Engineering

<<There's no question about it - excessive piping vibration can cause real problems. Threaded connections can loosen. Flanges can start leaking. Pipes can be knocked off their supports. An in extreme cases, a pipe fatigue failure can occur. But when is vibration excessive? Vibration is obviously too much if it causes a failure, but hindsight is 20/20. What about having to decide if vibration that is occurring is too much to tolerate? What about having to decide if vibration could be a problem while a piping system is being designed? The entire subject of piping vibration cannot be discussed in this article, but I will highlight several items to consider.>>

Flexible Operations Doesn't Always Mean Piping Flexibility

Carmagen Engineering

<<Several piping flexibility analyses were recently made for a large East Coast refinery to help design a number of bypasses. The bypasses were being installed to provide additional operational flexibility. However this additional flexibility in operations doesn't necessarily increase the piping flexibility of the system. This means that piping flexibility stresses and heat exchanger nozzle stresses may exceed allowable values if the new bypass lines are not properly designed.>>

Control of Piping Loads Imposed on Load-Sensitive Equipment

Carmagen Engineering

<<Properly designed piping systems keep stresses in the pipe wall itself within established allowable limits, and ensure that end point reaction loads do not overload connected equipment nozzles. While avoiding excessive equipment nozzle loads is important in all cases, this is especially true for piping systems connected to pumps, compressors and steam turbines. Excessive piping loads in these cases can cause high machine vibration, shaft misalignment, and coupling failures. These problems result in increased maintenance costs, and can lead to equipment and plant shutdowns. This series of articles will discuss suggestions for the design and installation of such machinery piping systems which will reduce the likelihood of nozzle overloads.>>

Piping Design Considerations to Control Loads on Load-Sensitive Equipment, Part 1

Carmagen Engineering

<<This article discusses one important piping design consideration, temperature. Future articles will discuss other design considerations. The piping system will have a design temperature associated with it, and this determines its stress and end point reaction loads. What's special about rotating equipment piping systems regarding temperature?>>

Piping Design Considerations to Control Loads on Load-Sensitive Equipment, Part 2

Carmagen Engineering

<<Piping must be designed and installed such that there is essentially zero forces and moments applied to the machinery nozzles when the system is not operating and is at ambient temperature. In order to accomplish this, sufficient pipe supports must be installed near the machine to carry the weight load. In addition, close flange alignment tolerances must be specified in the system design specification and adhered to during piping installation. >>

Minimizing Piping Friction Losses In Low-Pressure Regulating Valves

Control Engineering

<<One common type of installation for a pressure regulating valve is where the pressure is reduced to a very low value to supply or pressurize the system downstream of the valve. In the case of gas blanketing systems, system pressure could be reduced to as as much as one inch of water column. Liquid system losses may be several pounds per square inch. While these systems perform different functions, they have one feature in common--reduced pressure. Fluids flow by means of a pressure differential. If the system is to function, the backpressure must be less than the pressure being controlled at the valve. When designing and installing such a system, the engineer must specify the downstream piping and components that will keep the fluid resistance low. In no case can the valve be set for a pressure less than the backpressure created by the downstream.Backpressure from downstream piping and components is usually not an issue with systems operating at higher outlet pressures. But, it can be a problem with systems operating below 10 psi. As the pressure decreases, the potential for piping system-induced problems increases.>>

Design for Constructability (The Ten Commandments of KISS Design)

W. J. Boyce (similar to below, better graphics)

<<Designing for constructability will be just a buzzword without the right team. The team must have the right attitude, experience and authority (or the guts to take the authority) to make things happen. It is based on the same philosophy as the "Ten Commandments of KISS Design">>

Front End Change is Required When Designing for Constructability

Hydrocarbon Processing (W. J. Boyce)

<<Change is absolutely essential for progress. Without change we keep building the same old things to the same old standards, which is the very definition of No Progress. The change must be at the front-end of the project, during the conception phase. Changes after the conception phase and during the execution phase will be disruptive rather than constructive to the project. Open minds are also essential for change; closed minds do not accept change. An open mind found that the world is round; the closed minds said he's going to fall off the edge of the world. Change also requires a strong project management team with a project manager that has an executive role. Designing for Constructability is really Just updating old engineering standards, specifications and procedures. Most of these documents were developed years ago when the building materials were expensive and manpower was less expensive. These antiquated practices are costing companies, both owners and contractors, a lot of money on every project. This money doesn't benefit either owner or contractor; it goes right down the drain. When you hear, "We've always done it this way', you can be sure of obsolescence.>>

Obstacles in a Laminar Flow

Photographs of Experiments Conducted at MIT [DEAD LINK?]

Primary Patterns in Two-Phase Pipe Flow

Department of Petroleum and Geosystems Engineering, University of Texas at Austin

<<The purpose of this web site is to show, with video and photography, the primary patterns in two-phase pipe flow. The technique is to observe the flow behavior in two clear plexi-glass pipes which are connected in a loop. All the images seen are as a result of experimental data recorded and reproduced. The equipment used is located in the CPE building in the College of Engineering at the University of Texas at Austin. The lab encompasses a well that is five stories high and is used for a wide variety of fluid flow experiments.>>


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