This standard specification cancels and replaces IGS-M-TP-014-2-C(1):2007 , part 2 , which has been technically revised and updated .
It intended to be mainly used by all divisions of NIGC and EPC contractors , and has been prepared on interpretation of recognized standards , technical documents , knowledge , backgrounds and experiences in gas industries at national and international levels .
Iranian Gas Standards (IGS) are prepared , reviewed , and amended by technical standard committees within NIGC standardization division of research and technology management and submitted to Standard Council of NIGC for approval .
Iranian Gas Standard (IGS) are subjected to revision , amendment or withdrawal , if required, thus the latest edition of IGS shall be checked/inquired by NIGC users and EPC contractors .
Any comments from concerned parties or individuals on IGS standards are welcomed .
1.1. This standard specification specifies the NIGC requirements concerning properties , and relevant test methods for 3Ply co-extruded (see clause 3) cold applied plastic tape as external anti corrosion protection of field weld joint , fitting , and rehabilitation of steel pipeline main coating , by hand or hand applied machine application .
This standard specification cover the use of 3Ply co – extruded cold applied plastic tape (mechanical resistance class C) when the service temperature is within -10 to +50 °C .
The coating performance , test methods , and inspection shall be all in accordance with Table 1 .
1.2. Manufacturer/supplier shall provide all application instruction , safety data sheet , and guidelines require in practice on application .
Throughout this standard specification , the following standards and codes are referred to , the edition of them , that are in effect at the time of issues of this standard specification (2007) shall , to the extent specified herein , form part of this standard specification .
The applicability of changes in standards and codes that occur after the date of standards that referred , shall be mutually agreed upon by the purchaser and manufacturer or supplier .
TERMS AND DEFINITIONS
Refer to the structure of one co-extruded tape system .
3.2 Co – extrusion
Two or more materials are extruded simultaneously from a single die , so they fuse together to form a single structure . Laminated tape system is not accepted .
3.3 Self amalgamating (self fusing) :
3.3.1 Tape to tape
Two layer of 3Ply tape system in overlap area fuse to itself at room temperature with only slight pressure and over the time according to related method . This fusing action works only if the overlap layers are of same chemical nature (butyl rubber – butyl rubber) .
3.3.2 Within three individual ply
Only achievable by co – extruded method of production .
The coating system consist of a primer and a 3Ply plastic tape with following general description :
It shall be fast drying , butyl rubber base and special formulated to be used with 3Ply tape system .
The primer properties shall meet the requirements of Table 2 .
4.2 3Ply Tape System
It shoud consist of a polyethylene carrier film , coated on both sides with a plastic butyl rubber based compound in one co – extrusion process .
4.3 The Tape Application System
The tape shall be applied with 50% overlap on primed surface . It amalgamates at the overlap at ambient temperature to form a sleeve type coating .
4.4 The Tape and the Coating System
The properties shall meet the requirements of Table 1 .
7.1 3Ply Plastic Tape
The tape shall be delivered in roll form . A removable Interleaf shall be incorporated against adhesive compound to prevent sticking of layers . Each roll shall be individually put in plastic bag .
Rolls shall be suitably palletized and packed with plastic cover .
The primer shall be delivered in maximum 20 liters new steel drums .
The manufacturer/supplier shall provide sufficient information to identify the coating systems and shall supply as the minimum requirement , the technical information of the coating components as follows :
a- ISO 9001: 2000 " CERTIFICATION" for "Design & Manufacturing" of offered tape coating system(tape and primer) for "pipeline corrosion protection" issued by an internationally recognized body .
b- Certificate and approval test report from an internationally well known certifying body (i.e. DVGW(Germany) and ADVANTICA (UK) for the offered coating system for maximum continuous operating temperature up to 50 C and the compatibility with this standard specification .
Note : Other certificates from recognized certifying body shall be approved by standard council of NIGC .
c- Original technical catalogues , manufacturing product data sheet and application procedure recommendation and guidelines .
d- Material Safety Data Sheet (MSDS) for primer .
9. QUALITY ASSURANCE
Manufacturer shall operate an effective , documented quality system based on the relevant part of the BS EN ISO 9001:2000 and maintain records identifying the product , date of manufacturing ,batch numbers and all results of inspection and testing .
10. INSPECTION AND TESTING
The manufacturer set up and maintain such quality and inspection system as to ensure the material supplied , comply with all aspect of the requirements of this standard specification .
The manufacturer shall furnish the purchaser or its nominated inspector an overall compliance certificate accompanied with all in-production quality control test results for review . These documents and test results shall be traceable with regard to the batch number of each item .