• No results found

Possible Types of Data Error

Exercise 7 (Cable Tray Layout)

8.1 Possible Types of Data Error

The data consistency checking utility, available within Design’s Piping, Structural and Cable Tray

applications, checks the following aspects of your design for the following types of occurrences and other similar errors in the design.

Angular Alignment

Checks that components which are to be connected together are aligned in the same direction:

Axial Alignment

Checks that components which are to be connected together are aligned on a common axis:

Consistent Bores

Checks that components which are to be connected together have consistent bores:

Connection Types

Checks that components which are to be connected together have compatible connection types:

Minimum Tube Length

8.1.1 Design Tolerances

The misalignment between adjacent components can be measured using any of the following three parameters.

The offset distance between their p-arrive and p-leave axes The displacement angle between their p-arrive and p-leave axes

The ratio of the offset to the projected distance between the p-arrive and p-leave p-points (equivalent to the tangent of the angle parameter).

The user can specify maximum permissible values for any of these parameters, as well as minimum acceptable lengths of tube between components. The user can even specify different minimum lengths for different bore sizes. If any part of the design falls outside the current design limits, an error message will warn the user.

8.1.2 Starting the Data Consistency Checks

To carry out data consistency checking from within the Cabletray application, select Utilities > Data Consistency. You will see the following form:

By using this form, you can generate a diagnostic report on the data consistency of any part of your design.

You may list the report on your screen (in the area in the lower half of the form), or you may send it to a file from which you can print a hard copy version. Select Terminal or File and, in the latter case, specify the directory and filename. Choose

The hierarchic level at which you want to check the design using the Check list near top left of the form. The default is the current element.

The data checking utility allows a margin of acceptable error before it diagnoses that you may have a problem. These built–in tolerances have default values, but you may set your own values if you prefer.

www.aveva.com

As an example, by default your report will warn you of all lengths of tube in your design which are shorter

than 100mm. This allows you to decide whether each such length is adequate for welding procedures, bolt withdrawal, access, and so on. You can change the acceptable minimum length from 100mm, and may set different minima for up to ten different pipe bore ranges if you wish. For example:

A minimum length of 150mm for bores between 25 and 50. A minimum length of 300mm for bores between 50 and 100.

To change any of the consistency check tolerances, use the appropriate Parameters button on the form (Piping for our current examples).

You will see a subsidiary form on which you can change any of the current tolerances before carrying out the data checks.

8.1.3 The Report Format

The report comprises a header, giving the date and time, followed by an itemised list of the elements being checked, together with numbered diagnostic messages describing any potential problems. For example: DATE 11 FEBRUARY 99 TIME 14.12

PIPE /PIPE2

BRAN /PIPE2/B1

B 10 TAIL REFERENCE NOT SET END

If no problems are found, you will see the message: *** NO DATA INCONSISTENCIES ***

8.1.4 The Diagnostic Messages

You will find a full list of the data consistency diagnostic messages, each identified by a reference number, in the Design Reference Manual. With experience, you will be able to identify which messages indicate errors which must be corrected, and which are merely warnings of potential problems.

As an example, we will consider the design feature shown below, namely a Pipe to Pipe connection, and will look at some of the messages which might result.

The connection as shown is a valid one. If any of the connection types were changed, you might see the following messages:

A230 CONNECTION TYPE HCONN NOT SAME AS TERMINAL CONNECTION TYPE The connection types FBD-FBD in this example must be the same.

B230 CONNECTION TYPE TCONN NOT SAME AS TERMINAL CONNECTION TYPE The connection types GBD-GBD in this example must be the same.

HEAD TAIL PIPE A PIPE B GASK FLAN FLOW GBD HCONN FBD TCONN GBD FBD D430

(On GASK) B230 (On FLAN)E730

A230

D430 BAD ARRIVE CONNECTION TYPE

The connection types GBD-FBD in this example must be listed as compatible in the COCO tables. E730 LEAVE CONNECTION TYPE (of the Flange) NOT COMPATIBLE WITH TCONN

The connection types FBD-GBD in this example must be listed as compatible in the COCO tables.

8.1.5 Some Examples of Diagnostic Messages

The following examples explain the significance of some of the messages you might see during this training course:

Branch–Specific Diagnostics Branch Head Errors

The following diagnostics apply only to the Head of a Branch: A 10 HEAD REFERENCE NOT SET

The Head reference should only be unset (i.e. zero) if the Head Connection Type HCONN is set to OPEN, VENT, CLOS or DRAN.

A 20 HEAD REFERENCE POINTS TO NONEXISTENT ELEMENT

This error would result from the deletion of a component, such as a Nozzle, to which the Head of the Branch was originally connected.

A 30 BAD HEAD RETURN REFERENCE

The Head is connected to an element that does not refer back to the Branch. This can occur when the Head of a Branch is connected to another Branch, implying that a Tee should be placed somewhere along the second Branch. The error can also occur when two or more branches are inadvertently connected to the same terminal.

A200 DIRECTION HDIR NOT SAME AS TERMINAL DIRECTION

If the Head is connected to a terminal, such as a Nozzle or Tee, then the direction HDIR should always be identical to that of the appropriate p–point of the terminal.

A210 POSITION HPOS NOT SAME AS TERMINAL POSITION

If the Head is connected to a terminal, such as a Nozzle or Tee, then the position HPOS should always be identical to that of the appropriate p–point of the terminal.

A230 CONNECTION TYPE HCONN NOT SAME AS TERMINAL CONNECTION TYPE

If the Head is connected to a terminal, such as a Nozzle or Tee, then the connection type HCONN should always be identical to that of the appropriate p–point of the terminal.

A300 REFERENCE HSTUBE UNSET

There is more than 1mm of tube between the Head and the p–arrive of the first Component (or the Tail), but HSTUBE is unset.

A310 REFERENCE HSTUBE REFERS TO A NONEXISTENT SPCOM This may occur if part of the Specification has been deleted.

A320 HSTUBE PROBLEM, CATREF IN SPCOM IS UNSET This indicates an error in the Specification.

A330 HSTUBE PROBLEM, CATREF IN THE SPCOM REFERS TO NONEXISTENT Catalogue COMPONENT

This may occur if part of the Catalogue has been deleted or if the CATREF is unset. A400 HBORE NOT SAME AS BORE OF HSTUBE

The bore of any tube leading from the Head, determined from the Catalogue, should always be identical to HBORE.

A410 HCON NOT COMPATIBLE WITH CONNECTION TYPE OF HSTUBE

The connection type of any tube leading from the Head, determined from the Catalogue, should be compatible with HCONN.

A420 ISPEC REFERENCE POINTS TO NONEXISTENT ELEMENT

This error would occur if, for example, the Insulation Specification pointed to by ISPEC had been deleted. Branch Tail Errors

The same type of errors may occur to the Tail of a Branch. The message numbers are the same as for the Head errors but are preceded by a B. For example:

www.aveva.com

B 10 TAIL REFERENCE NOT SET

The Tail reference should only be unset (i.e. zero) if the Tail connection type TCONN is set to OPEN, VENT, CLOS or DRAN.

Plain Branch Errors

The following diagnostics can occur only for Branches with no piping components: C500 TUBE TOO SHORT BETWEEN HEAD AND TAIL

The distance between the Head position, HPOS, and the Tail position, TPOS, is greater than zero and less than the specified minimum tube length (default: 100mm).

C510 BAD HEAD TO TAIL GEOMETRY

Either the Head position, HPOS, does not lie at a positive distance along the line through TPOS in the direction TDIR or the Tail position, TPOS, does not lie at a positive distance along the line through HPOS in the direction HDIR.

The following illustration shows some typical examples:

C520 HBORE NOT SAME AS TBORE

When there are no components on the branch, the Head bore, HBORE, should be identical to the Tail bore, TBORE.

C530 HCONN IS NOT COMPATIBLE WITH TCONN

This implies that the Head is connected directly to the Tail with no Tube or piping components in between; hence the Head connection type, HCONN, must be compatible with the Tail connection type, TCONN. C540 THIS BRANCH HAS NO COMPONENTS

This does not necessarily indicate an error. It is output as a warning. Component–Specific Diagnostics

The following errors apply to individual piping components and, in some cases, to their adjacent connections. Some of the errors also apply to Nozzles.

All–Component Diagnostics

These are applicable to any component, regardless of its position in the network: D100 REFERENCE SPREF UNSET

This probably means that you have forgotten to choose the piping component correctly. D300 CONN REFERENCE NOT SET

Multi–way Components may be left unconnected only if the connection type of the relevant p–point is OPEN, CLOS, VENT, DRAN or NULL.

D310 CONN REFERENCE POINTS TO NON–EXISTENT BRANCH

This may occur if the Branch which is pointed to by the CONN reference has been deleted. D320 BAD CONN RETURN REFERENCE

This may occur if the Branch which is pointed to by the CONN reference has been reconnected to another terminal.

D400 ARRIVE TUBE LESS THAN TUBE MINIMUM. ACTUAL TUBE LENGTH IS...

The distance between the arrive p–point of this component and the leave p–point of the previous component (or Head) is greater than zero and less than the specified minimum tube length (default: 100mm).

D410 BAD ARRIVE GEOMETRY

The position and direction of the arrive p–point of this component are not correct with respect to the leave p– point of the previous component (or Head). The error could be caused by incorrect positioning of this component, the previous component (or Head) or both.

The following illustration shows some typical examples:

D420 BAD ARRIVE BORE

The bore of the arrive p–point of this component is not equal to the bore of the preceding tube or, if this component is not preceded by tube, to the bore of the leave p–point of the previous component (or HBORE). D430 BAD ARRIVE CONNECTION TYPE

The connection type of the arrive p–point of this component is not compatible with the preceding tube or, if this component is not preceded by tube, to the connection type of the leave p–point of the previous component (or HCONN).

D500 REFERENCE LSTUBE UNSET

You have probably forgotten to select the piping Component. D600 LEAVE BORE NOT SAME AS BORE OF LSTUBE

The bore of the leave p–point of this Component is not the same as the bore of the tube following the Component.

D610 LEAVE CONNECTION TYPE NOT COMPATIBLE WITH CONNECTION TYPE OF LSTUBE The connection type of the leave p–point of this Component is not compatible with the tube following the component.

End–Component Diagnostics

These are applicable only to the last component in a Branch:

E700 LEAVE TUBE LESS THAN TUBE MINIMUM. ACTUAL TUBE LENGTH IS...

The distance between the leave p–point of the current component and the tail position, TPOS, is greater than zero and less than the specified minimum tube length (default: 100mm).

E710 BAD LEAVE GEOMETRY

The position and direction of the leave p–point of this component are not correct with respect to the position, TPOS, and direction, TDIR, of the tail. The error could be caused by incorrect positioning of this component, the Tail, or both.

E720 LEAVE BORE NOT SAME AS TBORE

The bore of the leave p–point of this component is not the same as the tail bore, TBORE. E730 LEAVE CONNECTION TYPE NOT COMPATIBLE WITH TCONN

The connection type of the leave p–point of this component is not compatible with the tail connection type TCONN.

Related documents