A PTAXI allows a P-point to be defined in terms of an axis and a distance along that axis. A PTAXI has no member elements and has the following attributes:

NUMB must be set as a value. PAXI must be set as a direction - see Defining an Axis for details. The other attributes may be set as values or words (as appropriate), or in terms of parameters (which in turn are values or words). The classes of parameter which may be used depend on the class of Component (Piping Component, Joint or Fitting) which uses the P-point - see Parameters for details. PCON and PBOR are used for Piping Components only. They have no meaning if the P-point is used by a Joint or Fitting. For details of PSKEY settings, see Specifying Pipe End Conditions for use by ISODRAFT.

These conventions also apply to the attributes of the PTCAR and PTMIX elements described below. See Constructing 3D Pointsets for examples of setting these attributes.