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PDMS Lesson-1 (Model Editor)

Posted by Antony Thomas at Monday, March 23, 2009

PIPE RACK / WAYS & RACK PIPING Training

Posted by Antony Thomas at

uINTRODUCTION
u
u
PIPE RACK
§Pipe Rack design criteria
nShapes
nFuture Space
nWidth of Pipe Rack
nClearance
n
Pipe Rack Loading
uRACK PIPING
nPositions of Lines (Process & Utilities)
nHot Lines & Cold Lines
nBigger Size Lines
nPipe Spacing
nAnchor Bay
nUnit Battery Limit
nExpansion Loops
nPipe Route
n
Trays
n
 
 

VALVE & PIPING Training Book

Posted by Antony Thomas at

Introduction
Piping materials:
Metallic & Non-metallic
Metallic piping manufacturing process
Pipes specification:
Pipe size :Dimensions & Schedule Numbers
Pipe fittings:
Types & functions of fittings
Pipe connections:
Threading, welding, flanges
Gasket
Piping symbols & drawing
Hydrostatic testing
VALVE AND PIPING
PIPING
Contents
Piping coating & insulation
Pipe Supports & restraints
Maintenance of piping system

 

Download The File Here

 

“What is Valve trim?”

ProEngineer Piping Fittings in Wildfire 3.0

Posted by Antony Thomas at Thursday, March 12, 2009

Bentley AutoPIPE and STAAD.Pro

Posted by Antony Thomas at

Learn how to create more accurate models by combining piping and structural

 

Bentley AutoPIPE and STAAD.Pro - Part 1

 

Bentley AutoPIPE and STAAD.Pro - Part 2

 

Bentley AutoPIPE and STAAD.Pro - Part 3

 

 

Bentley AutoPIPE and STAAD.Pro - Part 4

 

 

 

Piping Stress Related Design Factors

Posted by Antony Thomas at Wednesday, March 11, 2009

There are five basic factors that influence piping and therefore piping stress in the process plant. There is temperature, pressure, weight, force and vibration. These factors will come in many forms and at different times. Stress problems become all the more complex because two or more of these will exist at the same time in the same piping system. The main objective of the focus when dealing with problems related to piping systems is not normally the pipe itself. In a very high percentage of the time it is not the pipe that is the weakest link. Note this: the pipe is normally stronger and/or less vulnerable to damage than what the pipe is connected to. Pumps are just one examples of equipment to which pipes are routinely connected. Misalignment problems caused by expansion (or contraction) in a poorly designed system can result in major equipment failure. Equipment failures can lead to the potential for fire, plant shutdown and loss of revenue. At this point it should be emphasized that the success (or failure) of the plant’s operation, years down the road can and will depend on what is done up front by all the members of the design team during the design stage. An important point to remember, “While analysis cannot create a good design, it can confirm a good design” (Improved Pump Load Evaluation,” Hydrocarbon Processing, April 1998, By: David W. Diehl, COADE Engineering Software, Inc Houston, TX). On the other hand, proper analysis will identify bad design and potential problems in a piping system design.

Stress Related Design Factors

Temperatures in piping systems may range from well over 1000o F (537.8 C) on the high side to below -200 o F (-128.8 C) on the low side. Each extreme on the temperature scale and everything in between brings its own problems. There will also be times when both high and low temperatures can occur in the same piping system. An example of this would be in piping that is installed in an arctic environment. The piping is installed outdoors where it is subjected to -100 o F (-73.3 C) over the arctic winter. Six to nine months later it is finally commissioned started up and may operate at five or six hundred degrees.

The problems that temperature causes is expansion (or contraction) in the piping system. Expansion or contraction in a piping system is an absolute. No matter what the designer or the stress engineer does they cannot prevent the action caused by heat or cold. Expansion or contraction in a piping system it self is not so much a problem. As we all know if a bare pipe was just lying on the ground in the middle of a dry barren desert it will absorb a lot of heat from just solar radiation. In the hot sun piece of pipe can reached 150 o F (65.5 C). The pipe will expand and with both ends loose it would not be a problem. However, when you connect the pipe to something, even if only one end is connected you may begin to have expansion related problems. When the pipe is anchored or connected to something at both ends you absolutely will have expansion induced problems. Expansion induced problems in a piping system is stress. There are a number of ways to handle expansion in piping systems. Flexible routing is the first and by far the cheapest and safest method for handling expansion in piping systems. The other way is the use of higher cost and less reliable flexible elements such as expansion joints.

Stress will exist in every piping system. If not identified and the proper action taken, stress will cause failure to equipment or elements in the piping system itself. Stress results in forces at equipment nozzles and at anchor pipe supports. Two piping configurations with the same pipe size, shape, dimensions, temperature and material but with different wall schedules (sch. 40 vs. sch. 160) will not generate the same stress.

Force in piping systems is not independent of the other factors. Primarily, force (as related to piping systems) is the result of expansion (temperature) and/or pressure acting on a piping configuration that is too stiff. This may cause the failure of a pipe support system or it may cause the damage or failure of a piece of equipment. Force, and the expansion that causes it, is best handled by a more flexible routing of the piping. Some people suggest that force can be reduced by the use of expansion joints. However we must remember that for an expansion joint to work there must be an opposite and equal force at both ends to make the element work. This tends to compound the problem rather than lessen it.

Pressure in piping systems also range from the very high to the very low. Piping systems with pressure as high as 35,000 psi in some plants are not unusual. On the other hand piping systems with pressures approaching full vacuum are also not unusual. The pressure (or lack of) in a piping system effects the wall thickness of the pipe. When you increase the wall thickness of the pipe you do two things. First, you increase the weight of the pipe. Second, you increase the stiffness of the pipe thus the stress intensification affecting forces. Increasing the wall thickness of the pipe is the primary method of compensating for increases in pressure. Other ways, depending on many factors include changing to a different material. With low or vacuum systems there are also other ways to prevent the collapse of the pipe wall. Among these the primary method is the addition of stiffening rings. Stiffing rings may be added internally or externally depending on the commodity type and the conditions.

Weight in a piping system is expressed normally as dead load. The weight of a piping system at any given point is made up of many elements. These include the weight of the pipe, the fittings, the valves, any attachments, and the insulation. There is also the test media (e. g. hydrotest water) or the process commodity whichever has the greater specific gravity. Piping systems are heavy, period. Everybody involved in the project needs to understand this and be aware that this weight exists and it needs to be supported. Ninety-nine times out of a hundred this weight will be supported from a structural pipe support (primary pipe support system) of some kind. However there are times when the piping (weight) is supported from a vessel or other type of equipment.

Vibrations will also occur in piping systems and come in two types. There is the basic mechanical vibration caused by the machines that the piping is connected to. Then, there is acoustic (or harmonic) vibration caused by the characteristics of the system itself. Typically the only place severe vibrations will be found is in piping connected to equipment such as positive displacement reciprocating pumps or high pressure multi-stage reciprocating compressors and where there is very high velocity gas flows.

Author:James O. Pennock is a former Piper with more than 45 years experience covering process plant engineering, design, training, pipe fabrication and construction. He is now retired and lives in Florida, USA.

Original from http://www.pipingdesigners.com/

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Piping Designer - Stress Training

Piping Designer - Stress Training

Posted by Antony Thomas at

Piping Designer Stress Training

What does the piping designer need to know? Piping design is more than just knowing how to turn on the computer, how to find the piping menus and the difference between paper space and model space. So, appropriately, what else does the designer need to know about piping design besides how to connect a piece of pipe to a fitting?

Here is a list of some of the most basic of things that a good piping designer should know. Thinking about every one of these items should be as natural as breathing for a good piping designer.

· Allowable pipe spans – All designer need to know and understand the span capabilities of pipe in the different schedules for a wide variety of common piping materials. When a new project introduces a new material with severely reduced span capabilities; supplemental training may be required.

· Expansion of pipe – All designers must understand that they need to treat a piping system as though it is alive. It has a temperature and that temperature causes it to grow and move. That growth and movement must be allowed for and incorporated in the overall design. Not just of that specific line but for all other lines close by. The process of expansion in a pipe or group of pipes will also exert frictional forces or anchor forces on the pipe supports they come in contact with.

· Routing for flexibility – The piping designer must understand how to route pipe for flexibility. Routing for flexibility can normally be achieved in the most natural routing of the pipeline from its origin to its terminus. Routing for flexibility means (a) do not run a pipe in a straight line from origin to terminus and (b) building flexibility into the pipe routing is far cheaper and more reliable than expansion joints.

· Weight and loads (live loads and dead loads) – The piping designer needs to understand the effects of weight and loading. They need to know and understand that everything has a weight. They need to be able recognize when there is going to be a concentrated load. They need to have access to basic weight tables for all the standard pipe schedules, pipe fittings, flanges, valves for steel pipe. They also need to have the weight tables for other materials or a table of correction factors for these other materials vs. carbon steel. They need to be able to recognize when downward expansion in a piping system is present and is adding live loads to a support or equipment nozzle.

· Equipment piping – The piping designer needs to know the right and the wrong way to pipe up (connect pipe to) different kinds of equipment. This includes pumps, compressors, exchangers, filters or any special equipment to be used on a specific project.

· Vessel piping – The piping designer also needs to understand about the connecting, supporting and guiding of piping attached to vessels (horizontal or vertical) and tanks. They need to know that nozzle loading is important and does have limitations.

· Rack piping – The designer needs to understand that there is a logical approach to the placement of piping in (or on) a pipe rack. It does not matter how wide or how high the rack or what kind of plant, the logic still applies. Starting from one or both outside edges the largest and hottest lines are sequenced in such a manner that allows for the nesting of any required expansion loops. The spacing of the lines must also allow for the bowing effect at the loops caused by the expansion.

· Expansion loops – The designer needs to understand and be able to use simple rules and methods for sizing loops in rack piping. This should include the most common sizes, schedules and materials.

· Cold spring/Pre-spring – Designers should understand the basics rules of cold spring and pre-spring. They need to understand what each one is along with when to and when not to use each.

 

cheers..

 

Piping Engineering Leadership for Process Plant Projects

Posted by Antony Thomas at Wednesday, March 04, 2009

This Book having the following index

Roles and Responsibilities
1 Piping
2 Engineering Management and Other Engineering
Disciplines
3 Nonengineering Groups
Pt. II Project Descriptions
4 Project Types, Terms, and Execution Philosophy
5 Grassroots Projects
6 Revamp and Rebuild Projects
Pt. III Procurement, Pipe Fabrication, and Contracts
7 Procurement Responsibilities
8 Pipe Shop Fabrication
9 Contracts and Construction Work Packages (CWP)

Pt. IV Project Execution 135
10 Project Definition - Scope of Work
11 Estimating
12 Scheduling
13 Planning and Organizing
14 Staffing and Directing
15 Controlling Change
16 Reporting
17 Project Completion

Download the file

Piping Components - Explanation

Posted by Antony Thomas at Sunday, March 01, 2009

In this file, many piping components are explained.

For example:

Steam Trap and Drain Trap

Spring Support

Process Vent

Process Drain

Sampling Connection

Sample Cooler

Thermowell

Gate Valve

Globe Valve

Download the file here: Piping Components explanation

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PIPING QUIZ & ANSWERS

Piping Questions and Answers

PDMS Commands

Posted by Antony Thomas at

A new set of PDMS Commands are compiled here for download and use. A PDMS Piping designer must have this file.
The language used in the file seems that it is Italian.
Click here to download the file: PDMS Command

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PDMS Latest Commands

PDMS Latest Commands

Posted by Antony Thomas at

In this file, there are plenty of PDMS Commands are compiled.
For example see the below listed commands.
show _CDCOMP to show the Piping Components form
Q ADEG (DRAFT) GIVES THE C/VIEW ANGLE ( ie 90 DEG )
Q ANGLE (HVAC) GIVES THE CE ANGLE
Q ATEX(DRAFT) GIVES THE SLAB/GLAB TEXT ATTRIBUTES
Q ATT GIVES THE CE ATTRIBUTES
Q BANG GIVES THE CE BETA ANGLE
Q BORE (PIPING) GIVES THE PIPE INSIDE DIA.
Q BSRF (DRAFT) GIVES THE ATTACHEDDRG/SHT (DRWG LVL)
Q BTEX(DRAFT) GIVES THE DEAD TEXT ATTRIBUTES
Q CHEI (DRAFT) GIVES THE TEXT CHARACTER HEIGHT
Q COL ACT GIVES THE CURRENT ACTIVE COLOUR
Q COL AIDS GIVES THE CURRENT AID LINE COLOUR
Q COL CE GIVES THE CURRENT ATTRIBUTED COLOUR
Q COL VIS GIVES THE CURRENT VISIBLE COLOUR
Q COL 4 (ETC) GIVES THE ATTRIBUTED COLOUR (YELLOW)
To Download the file Click Here: PDMS Command

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