ISO 14692-4:2002 pdf download

ISO 14692-4:2002 pdf download.Petroleum and natural gas industries —Glass-reinforced plastics (GRP) piping -Part 4: Fabrication, installation and operation.
If shown on isometric drawings, the fabrication shall include “cut-to-fit” lengths and field joints on fabricated pieces to allow for the setting up of pipework accurately on-site between fixed points. The “cut-to-fit” dimension shall be 150 mm of pipe additional to the length shown on the piping drawings. For hook-up spools, the “cut-to-fit” dimension shall be a minimum of 250 mm in each global direction. “Cut-to-fit” lengths shall be left square and plain.
The installer shall give due consideration to the following:
a) the need to avoid overstressing of GRP components by the forced pulling of GRP pipework to facilitate alignment at joints, and particularly at flanged joints;
b) the need to ensure that valves or other heavy attached equipment are independently supported;
c) the need to prevent damage to joints when handling small-diameter thick-walled pipe, e.g. due to fire protection;
NOTE This is because the high rigidity of the pipe concentrates loading at the thinner sections of pipe wall adjacent to the joint.
d) the preferred location of the last site joint in a piping loop to ensure that necessary access is available, since this joint is often the most difficult to complete;
e) delays caused by the time required for adhesive and laminated joints to cure without being disturbed. The scheduling of surrounding construction activities shall take into account the risk of possible disturbances to such joints;
f) the need to provide temporary protection for installed GRP piping if risk of mechanical damage is high. The installer shall also consider correct sequencing of fabrication activities to minimize risk of damage;
g) the need to prevent overheating of the GRP pipe material by electric surface heating, if applied. Heat tracing should be spirally wound onto GRP pipe in order to distribute the heat evenly around the pipe wall. Heat distribution can be improved if aluminium foil is first wrapped around the pipe. Care shall be taken that the tracing is not wound too tightly onto the pipework or it may be damaged when the pipe expands;
h) provision of suitable joints to facilitate isolation or access to the pipe for maintenance purposes.
High levels of supervision and inspection shall be adopted for piping which will be difficult to repair on site
(e.g. ballast lines due to be cast in concrete, and piping in ballast water tanks).
5.5.4.2 Components fabricated on-site
All processes used to fabricate spoolpieces and components on-site, e.g. mitred elbows and laterals, shall have been qualified according to procedures given in 6.2.3.3 of ISO 14692-2:2002.
5.5.4.3 Tolerances
Global tolerances shall be within ± 6 mm in all directions, unless otherwise shown on the approved drawings.
Dimensional tolerances for finished piping are given in Table 1. The dimension numbers are shown in Figure 1.
The acceptable tolerances for misalignment of flanges during installation are given in Table 2. It is common practice for some flanges to be manufactured with bolt holes larger than the size of bolt being used with the flange. Typically, the hole will be 3 mm larger. This should be taken into account when assessing the flange misalignment tolerance in Tables 1 and 2.
5.5.4.4 Electrical conductivity and electrostatic dissipative properties
If electrical conductivity requirements are specified, the installer shall verify the electrical conductivity and/or earth linkage of the piping as it is installed according to the requirements documented by the system designer (see 5.3).
The installer shall measure one or more of the following properties as required:
a) continuity along the component between earth-bonding points;
b) maximum resistance to earth from a point on the inside of the pipe;
c) maximum resistance to earth from a point on the outside of the pipe or the fire-protective coating or thermal insulation cladding;
d) maximum resistance to earth of metal components located on the pipe;
e) recommended maximum distance between earthing points, based on the conductivity properties of the pipe system;
f) maximum surface resistivity on the outside of the pipe or the fire-protective coating or thermal insulation cladding;
g) charge-shielding properties of the pipe;
h) charge-decay properties of the outside surface of the pipe or the fire-protective coating or thermal insulation cladding.