Minimum bend corner radius

The Minimum Bend Corner Radius design rule checks that a bend corner is not too small, based on the current diameter of the stock. A bend corner is created through the Routing Bend Corner tool.

The minimum is based on a ratio to the diameter — the value of the DIAMETER characteristic on the stock — to the bend radius. This minimum ratio is specified in the Application View as ROUTE_MIN_BEND_RADIUS_COEFF in the PREFERENCES block of the Application View file. This may be expressed as (bend radius/DIAMETER) = ROUTING_MIN_BEND_RADIUS_COEFF.

Minimum curve radius

The Minimum Curve Radius design rule verifies that the radius for a curve segment (spline or arc) is at least:

CURVE_MIN_BEND_RADIUS_COEFF times the DIAMETER of the stock along the segment.

• CURVE_MIN_BEND_RADIUS_COEFF is a User Preference defined in the Application View file.
• DIAMETER is a Routing characteristic which must be attached to the stock.
• Splines are checked at intervals along the spline determined by the setting of CHECK_SPLINE_ARC_LEN, a user preference defined in the Application View File.

Minimum bend radius spline

The Minimum Bend Radius Spline design rule is valid for splines only. This design rule highlights specific violation locations for a spline violating the minimum curve bend radius design rule by creating and highlighting temporary points on either side of the violating spline and temporary splines at violation locations. (See Electrical Design Rules for more details.)

Minimum straight length

The Minimum Straight Length design rule checks that a straight section of stock adjacent to a bend is not too short, based on the current diameter of the stock. The minimum is based on a ratio of the current diameter of the stock to the length of the straight section. This minimum ratio is specified in the Application View as ROUTING_MIN_STRAIGHT_LENGTH_COEFF in the PREFERENCES block of the Application View. This could be expressed as (straight length/DIAMETER) = ROUTING_MIN_STRAIGHT_LENGTH_COEFF.

Preferred bend radius

You can use the Preferred Bend Radius check in place of the Minimum Bend Radius check to ensure that all bends are of exactly the same ratio to the stock diameter. To use this design rule, the APV file needs to be changed to use the design rule function CHECK_PREF_BEND_RADIUS. The preference ROUTING_PREF_BEND_RADIUS_COEFF controls the preferred ratio.

Connection compatibility

The Connection Compatibility design rule checks that connected objects are compatible. This includes part-to-part connections and part-to-stock connections. Three characteristics are checked for compatibility between the connected objects: NPS SIZE (or Diameter), GENDER, and CONNECTION_TYPE.

• NPS SIZE and CONNECTION_TYPE must be equal on both ports.
• GENDER must not be equal.
• There is no customization preference associated with the Connection Compatibility design rule.

Related topics

• Learn more: Mechanical design rules