Create and Use Pipe Racks

In Pipe Router, the term pipe rack is used to describe a group of routing planes which enable you to automatically model the routing patterns used on a physical pipe rack.

A pipe rack is made up of routing planes (RPLAs) created within a routing plane group (RPLG). The planes represent travel planes and entry/exit planes.

You can create pipe racks with several levels, that is several travel planes. For each level of a pipe rack, a travel plane must be created to control the direction in which pipes travel along the rack and at least one entry/exit plane to ensure that pipes enter onto and exit from the rack perpendicularly, either from above or below. Each pipe rack must have at least one travel plane and at least one entry/exit plane. The direction of travel is the X direction (length) for travel planes and the Y direction (width) for entry and exit planes.

Pipe Router assumes that the RPLAs in an RPLG have their centres on a vertical line. The entry and exit planes must be:

• At least as long (in the X direction) as the travel Plane(s)

• Wider (in the Y direction) than the travel planes

• At least twice the bend length.

When entry/exit planes are created, you must specify the distance by which they overhang the travel planes. The overhang ensures that the vertical legs of pipes which enter and exit the rack are clear of the pipe rack structure.

A pipe rack may have an upper entry/exit plane, a lower entry/exit or both, depending on the way in which the pipes are to enter and exit a pipe rack. In a pipe rack that has several levels, an entry/exit plane can be used by more than one level.

You can manually associate a pipe rack with individual branches or you can tell Pipe Router to automatically search for and make use of any pipe racks which exist within the search volume of a branch or branches. The default search volume is the volume between the head and tail of a pipe, and it can be extended as specified on the Pipe Router Defaults form.

Pipe Router will select the closest pipe rack to the head in the search volume, whose direction will take the pipe closer to the tail, and providing that when using it, the pipe will travel on the rack for longer than the Minimum Travel Distance as defined on the Pipe Router Defaults window.

Rack or Plane as Last Constraint

If you are responsible for one area of a plant and a different designer is responsible for an adjacent area, a branch may run out of the first area on a pipe rack. You must put the rack in the constraint list and run the branch to the area limits., by using the free tail option from the Branch Details window. A branch has a free tail when the tail is either not connected or is directly connected to another branch; and the tail is not locked.

A free tail can be specified immediately after a pipe-rack or plane. When a branch has a plane or rack as its last constraint and a free tail, Pipe Router will route the branch onto the plane or rack. It will travel in the direction implied by the tail direction until it reaches the edge of the plane or rack and then will become the tail position.

For example: User-A is responsible for one area of a plant and User-B is responsible for an adjacent area. A branch /P100/B1 runs out of the User-A's area on a pipe-rack. User-A puts the rack in the constraint list with the end of the travel plane at the limits, and specifies the tail direction and that the tail is free. PDMS Router will pack the pipe onto the rack and run it to the end of the rack.

User-B connects the head of a Pipe /P200/B1 to the tail of /P100/B1 and begins routing from this point. User-B must ensure that the position of the head of branch /P200/B1 is initially unset. PDMS Router will use the Branch Lock so that the head /P200/B1moves if the connected tail moves. If the pipe starts by travelling along an extension of the rack in User-A's area then User-B has a rack with its starting edge at the limit to represent this.

How Pipes are Routed on a Pipe Rack

By default, Pipe Router avoids pockets by first finding the travel plane. If the Head is above the plane, the Pipe will enter from above the plane. If the Head is below the plane, the Pipe will enter from below the plane. Exit from the plane is similarly controlled by the position of the Tail relative to the plane.

There are three routing rules which enable you to set which planes are used as entry, exit or travel planes on pipe racks. The rules are:

• Pipe rack travel plane selection

  Use this rule to specify which level of a multi‑level pipe rack you want to use to route a particular type of branch.

• Pipe Rack entry plane selection

  Use this rule to specify the way in which pipes enter onto a rack, based on the contents of the pipe. In order to use this rule, you must set up an attribute which defines the pipe’s contents, for example vapour or liquid.

• Pipe Rack exit plane selection

  Use this rule to specify the way in which pipes exit from a rack, based on the contents of the pipe. In order to use this rule, you must set up an attribute which defines the pipe’s contents. If no rule exists, the entry plane will be used.

Pipe Packing Defaults

By default, Pipe Router will run pipes along Routing planes with the wall-to-wall Pipe Gap, with any rounding factor for the positioning, as given on the Pipe Router Defaults window. for further information about how Pipes are packed on Planes and Racks, see Pipe Packing.

Methods for Creating Pipe Racks

You can create a pipe rack using either of the following methods:

• Convert an existing steelwork structure into a pipe rack, using elements of the steelwork as reference points for the position and dimensions of the planes.

• Create the routing planes which model the behavior of a pipe rack and then add the steelwork later, once you are satisfied with the route. In Pipe Router, this is referred to as a conceptual pipe rack.

Converting a Steelwork Structure to a Pipe Rack

To create a pipe rack, using elements of a steelwork structure as reference points to position the planes. Before a pipe rack is created, pipes need to be created to route via the pipe rack. The ur must navigate to the STRU element, the current element must be a STRU, FRMW or SBFR as routing plane groups can only be create routing plane groups inside a these elements.

From the Pipe Router window, select Create > Pipe Rack Planes to display the Create Pipe Rack window.

In the Name box, input a name for the pipe rack, (the name of the STRU element which owns the pipe rack elements is shown under the Name).

You must select an element in the steelwork, click Convert. The Pipe Rack Definition window is displayed and you are prompted to pick an element in the steelwork to create the rack from.

You can define values which apply to all the planes in the Rack. When a pipe rack is created in this way, the following parameters have been derived from the existing structure and cannot be changed at this point:

• Elevation of Anchor Plane

• Elevation between Planes

• Number of Travel Planes

• Number of Entry/Exit Planes.

  Note:
  The Anchor Plane is the lowest travel plane in the rack.

The Overhang of Entry/Exit planes can be changed. The default value is set on the Pipe Router Defaults window.

You can set any Options to apply to all planes in the Rack. for further information on Pipe to Pipe Gap and Packing Method.

Click OK on the Pipe Rack Definition window, the Planes part of the Create Pipe Rack window is now populated.

Click Dismiss to discard any changes.

Note:
Routing planes are added with transparency, the degree of transparency is controlled by the Drawlist.

Pipe Router has automatically filled in the Rack Direction, and the Dimensions of the rack. The details of the Planes will be shown in the list of Planes at the bottom of the window. The Plane attributes area of the window, the values shown are those for the plane selected in the Planes list. The Plane Attributes can be edited for individual planes by changing the values in the window and then click Include to create a new plane or Replace to replace the plane selected in the list.

Add a Pipe Rack to a Branch

There are two ways in which branches are associated with a pipe rack:

• Manually add a pipe rack to the list of constraints for a branch.

• Pipe Router will automatically make use of any pipe racks that exist within a certain area between the head and tail of a branch.

Automatically Adding Pipe Racks to a Branch

To automatically add a pipe rack to the list of constraints for a branch:

Select the branches from the Pipe Router window and select Modify > Branch > Add Pipe Rack > Automatically. The status line states which rack is being added to the constraints lists for the selected branches.

Manually Adding Pipe Racks to a Branch

To manually add a pipe rack to the list of constraints for a branch, from the Pipe Router window, select the branch, select Modify > Branch > Add Pipe Rack > Selection.

The Add Pipe Rack window is displayed which contains a list of the pipe racks that are available for selection.

You must select the required rack, click OK to add the rack to the Components/Constraint list for the selected branch or Cancel to discard any selections and close the Add Pipe Rack window.

You must then route all the branches using the Pipe Router window.

The default route creates pockets in three of the Pipes. By default, Pipe Router routes all pipes that are associated with a pipe rack along the first travel plane that it finds in the routing plane group (RPLG).

Note:
Routing rules can be used to achieve a better route: for further information, refer to Automatic Pipe Routing Administration.

Create a Conceptual Pipe Rack

You can also route pipes using a conceptual pipe rack , that is, a pipe rack without any associated steelwork. The steelwork can be added later.

You can route the pipes before adding the pipe rack, which will allow you to see the effect of the routing plane on the route taken by the pipes.

Note:
Routing plane groups can only be created inside a STRU element.

Navigate to the zone ROUTERSITE/STRU, from the Pipe Router window, select Create > Structure for Planes.

The Name Structure for RPLG window is displayed and an STRU element is created in the design hierarchy:

In the Name box, input the name for the structure.

Click OK to name the STRU element and close the Name Structure for RPLG window or Cancel to discard any inputs and close the Name Structure for RPLG window.

From the Pipe Router window, select Create > Pipe Rack Planes. The Create Pipe Rack window is displayed. You must now define the Pipe Rack, for further information on how to populate this window, refer to Create and Use Pipe Racks. Once the Pipe Rack has been created, click Create MulTiple planes the Pipe Rack Definition window is displayed. You must now define the Pipe Rack, for further information, refer to Create and Use Pipe Racks.

Pipe Router creates an outline of all the planes for the rack and displays an arrow on the travel planes to indicate the travel direction of the rack, which enables you to check whether the plane is acceptable.

Add the pipe rack to the Branches, and route the pipes The route taken by the pipes will look as shown: