Vietnam: What are the details of National Standard TCVN 9562: 2017 on Glass-reinforced thermosetting plastics (GRP) systems based on unsaturated polyester (UP) resin?
- What is the scope of regulation of National Standard TCVN 9562: 2017 on Glass-reinforced thermosetting plastics (GRP) systems based on unsaturated polyester (UP) resin in Vietnam?
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- What are the general regulations of materials for making Glass-reinforced thermosetting plastics systems based on unsaturated polyester resin in Vietnam?
What is the scope of regulation of National Standard TCVN 9562: 2017 on Glass-reinforced thermosetting plastics (GRP) systems based on unsaturated polyester (UP) resin in Vietnam?
In Section 1, National Standard TCVN 9562: 2017 on Glass-reinforced thermosetting plastics systems based on unsaturated polyester resin in Vietnam, the scope of regulation is specified as follows:
This National Standard specifies the properties of Glass-reinforced thermosetting plastics systems based on unsaturated polyester resin. This National Standard is suitable for all types of pressurized or non-pressure water supply systems, including but not limited to, such as raw water, fire fighting water, cooling water, clean water, salt water, seawater, power plant water, water in production lines and water used for other applications. This National Standard applies to Glass-reinforced thermosetting plastics systems based on unsaturated polyester resin, which have flexible or rigid joints, with or without the ability to withstand head loads, used mainly in direct underground installations.
Note 1: For the purposes of this National Standard, the unsaturated polyester (UP) resin also includes vinyl-ester (VE) resin.
Note 2: Pipe systems conforming to this National Standard may also be used for non-buried applications, provided environmental influences and supports are considered during the design of pipes, fittings, and joints.
Note 3: This National Standard may also apply to other installations such as repairs and renovations of existing pipe systems.
Note 4: This National Standard is also used as a reference document in ISO 25780, which specifies requirements for GRP pipes used in jacking installations.
The requirements for the glass pressure design of pipes as a reference document in this National Standard meet the requirements of ISO/TS 20656-1 and the general principles for the reliability of structures detailed in ISO 2394 and EN 1990. These standards set out the harmonized process of design practice and address the possibility of destruction, as well as the results of destruction. This design practice is based on the concept of safety factors as well as risk assessment techniques.
This National Standard applies to pipes, fittings, and their joints in nominal sizes from DN 50 to DN 4000, used to transport water at temperatures up to 50°C, under or non-pressure conditions. In a piping system, pipes and spare parts with different nominal pressure and hardness grades can be used together. Article 4 regulates general aspects of GRP UP piping systems used for supplying pressurized or non-pressurized water.
Article 5 specifies the characteristics of GRP UP pipes, with or without aggregates and/or lining. Pipes may have a thermoplastic or thermosetting lining. Article 5 also specifies test parameters for the methods invoked in this National Standard.
Article 6 specifies the characteristics of GRP UP spare parts, with or without thermoplastic or thermosetting lining, for water transportation. Article 6 prescribes size requirements and feature requirements for curved, branched, and stepped lines, starting belts, and flange joints. Article 6 sets out the requirements for verifying the structural design of spare parts. This applies to spare parts made using the following techniques:
- Machining from straight pipes;
- Casting by method
1) | Single strand wrap |
2) | Wrap the bandage |
3) | Manual rolling |
4) | Hot or cold-pressed molding |
Article 7 applies to joints used in buried and floating GRP UP pipe systems, used to transport water. This sets out the requirements for verifying the design of the joint. Article 7 specifies the typical test performance requirements for the joints below, which are functions of the declared nominal pressure of the system or pipeline:
a) | Heath and non-heated head joints (including double calcined heads) or mechanical joints; |
b) | The firing and unheated end joints are locked; |
c) | Adhesive or coated joints; |
d) | Bolt-catching flange joints. |
What are the types of glass used for the manufacture of reinforcing compounds in Vietnam?
In subsection 4.2.2, Section 4, National Standard TCVN 9562: 2017 as follows:
Reinforcement
Glass used for the manufacture of reinforcing compounds must be of one of the following types:
a) "E" glass, consisting mainly of oxides of silicon, aluminum and calcium (calcosilicate aluminum glass) or silicon, aluminum and boron (aluminium borosilicate glass).
b) "C" glass consisting mainly of oxides of slicon, sodium, calcium and boron (alkali metal calcium glass with high boron trioxide content) for applications requiring high chemical strength.
c) "R" glass, consisting mainly of oxides of silicon, aluminum, calcium and magnesium without boron.
d) "E-CR" glass, composed of boron-free modified E glass to increase corrosion resistance to most acids.
Whatever the type of glass, small amounts of oxides of other metals may exist.
NOTE The descriptions of type C glass and type E glass conform to those outlined in ISO 2078, but are more specific.
The reinforcement must be made from type E (E-CR), type C or type R continuous glass filament, and must have a surface finish suitable to the resin used. It can be used in any form, for example, continuous or truncated filament, strip or roving, mat or fabric. Mat or synthetic fiber (organic) surface film can be used on the surface of the parts.
Accordingly, glass used for the manufacture of reinforcing compounds in Vietnam must be of one of the following types:
- "E" glass, consisting mainly of oxides of silicon, aluminum, and calcium (calcosilicate aluminum glass) or silicon, aluminum and boron (aluminium borosilicate glass).
- "C" glass consisting mainly of oxides of silicon, sodium, calcium and boron (alkali metal calcium glass with high boron trioxide content) for applications requiring high chemical strength.
- "R" glass, consisting mainly of oxides of silicon, aluminum, calcium and magnesium without boron.
- "E-CR" glass, composed of boron-free modified E glass to increase corrosion resistance to most acids.
What are the general regulations of materials for making Glass-reinforced thermosetting plastics systems based on unsaturated polyester resin in Vietnam?
In subsection 4.2.1 Section 4, National Standard TCVN 9562: 2017, the general regulations of materials for making Glass-reinforced thermosetting plastics systems based on unsaturated polyester resin in Vietnam are:
Pipes or fittings shall be fabricated using continuous and/or truncated fiberglass, strip or roving, mat or fabric, and polyester resins, with or without fillers, and may have additives necessary to improve the specific properties of the plastic, pipes or parts may also be combined with aggregates if required, and thermoplastic liners or another thermostat.
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