GRP Pipes                : produced by filament winding process conforming to ASTM and other international standards, such as ASTM 2996, ASTM 3517, AWWA C – 950 and many others. Or Steel Pipes To ASTM. Or HDPE Pipe to EN – 12201.

HDPE Pipes             : Extruded PE 100 & 80, Pressure rating up to 16 bars according to British Standard EN 12201.

INSULATION:              SPS pre-insulated pipes uses polyol form insulation, this rigid foam provides the lowest thermal conductivity of any

Commercially available factory applied for insulation. It has a high compressive strength and is dimensionally stable.

POLYOL   is a blend of ployol, surfactants, catalysts and HCFC 14 lb blowing agent. The polyol is specifically developed as a two component system for rigid Polyurethane Foam insulation.

Application

Product is used in the manufacture of insulated pipes by pouring in place. 

Insulation Thickness:

Insulation thickness for the pipe size shall be calculated. Or as per the Client's specification.

Physical and Chemical Properties 

Appearance                                     :                       Clear amber colored liquid

Viscosity @ 20 deg. C                     :                       300 +/- 50 cps

Specific gravity @ 20 deg. C          :                       1.18 gm/cc

Typical Reaction time and Density (Hand Mixed/Cup Test)

Both components at 20 deg. C

Cream Time                          :                         26      –          32 sec.

Gel Time                                :                       110     -           125 sec.

Tack Free Time                     :                       190     -           210 sec.

Rise Time                              :                       235     -           255 sec.

Free Rise Density                 :                         40      -             45 kg/M3

Molded Density                     :                         45      -             55 kg/M3

  Dimensional Stability

% linear changes:                 BS 4370                     %Volume changes:                 

24 hrs. @ 100deg.C:1.0% max.24 hrs. @ 100deg.C. 1.0% max.

 7 days @ -15 deg.C:2.0% max.7 days  @ -15 deg.C.:    2.0% max.

 7 days @  70 deg.C :1.0% max.7 days @  70 deg.C.:    2.0% max.

 Performance

Thermal Conductivity (k – factor):    ASTM C177  :           0.023w/mdeg. K

Minimum closed cell content:           ASTM D 2826:          93        %

 Water Vapor Transmission  :           ASTM E 96    :           20        Pgm/Nh

Burning Characteristics

 Self extinguishing to (ASTM 1692 – MD/74)         Classification – B2

            Flame Spread                                   :           25 mm or less

            Extinguishing Time                           :           50 sec.

Handling and Storage

POLYOL should be stored at room temperature below 25 deg. C in sealed drums. Close all drums after use to prevent loss of blowing agent and absorption of moisture.

JACKETING / OUTER PROTECTION CASING

The purpose of the outer jacket over the insulation is to protect the foam from mechanical damage and water intrusion. The most common jacket for below ground applications is HDPE. For aboveground application a GRP jacket is advantage.

GRP JACKET shall be used for buried or above ground applications. Jacket materials shall be GRP filament wound material same material and cell classification as the line core pipe and fittings. Minimum wall thickness of pipe jacket will be calculated depending on the environmental conditions.

The GRP jacket has also top coat inhibitors in order to protect the grp from ultra – violet degradation and can be used in above ground installation for unlimited period of time. The jacketing allows the insulation to retain flexibility almost identical to that of the core pipe. This permits the jacketed pipe to

Conform in unstable soils. For aboveground application in abusive environments, generally a heavier wall thickness is desirable.

Minimum Grp Jacket thickness is 5.0 mm.

SPS GRP JACKET TECHNICAL SPECIFICATION

RAW MATERIALS

Raw Materials used to manufacture SPS GRP JACKET are the following:

RESINS

SPS usually uses Isophtalic polyester resin

Some typical Properties of liquid resins are:

The cured resin has the following properties at room temperature:

 Resin properties are measured on every single batch according to SPS internal Quality Control and Inspection Plan.

GLASS REINFORCEMENTS

Glass Reinforcements are made starting from two different types of glass composition:

“C” glass which performs very good properties of chemical inertness versus chemical corrosion.

“E” glass has a very high mechanical strength. The glass reinforcements specified

By SPS consist of: Surfacing veils of  “C” glass, used as reinforcement for the

first ply of the laminate.      Mats of chopped strands  of “E” glass, used in hand lay up operations  such as the manufacturing of fittings.

 The significant mechanical properties of fiberglass used as reinforcement are the following:

 PROPERTIES OF LAMINATES

The following figures refer to laminated obtained by the filament winding process with a winding angle of 55 degrees.  The winding angle can be varied to increase properties in the axial or circumferential directions. 

Design Basis Properties

Mechanical Properties

Other Physical Properties

Electrical Conductivity

Standard Piping        10^9  M Ohm/m

Conductive Piping       <  1 M Ohm/m 

 High Density Polyethylene (HDPE) Pipe Seamless extruded high density, Ultra-violet stabilized corona-treated, having a material classification according to EN 12201.

FITTINGS

Insulation kits are available for all standard GRP of HDPE fittings, common cast iron fittings, flange to flange, and various types of water piping connections. Insulation kits are factory molded from rigid polyurethane foam and contain all components required to field fitting insulation.

(Pre insulated fitting with grp Jacketing)                                               (Pre insulated fitting without Jacketing)      

 JOINTS

The following methods of GRP pipe joining are acceptable. 

SUPPORTS (OPTIONAL)

Support for GRP core pipe is made of steel saddle plate to be laminated on the pipe prior to the installation of outer casing/ jacket and the injection of polyurethane foam.

(Pipe With Bottom Support)

DETECTION AND LOCATION OF LEAKS IN PIPING SYSTEM (OPTIONAL)

 Whenever liquids are transported and stored, there is always a risk of leakage. The cause of the leak could be deficiencies in materials, corrosion, errors or mistake in design and/or during installation, lack of maintenance or supervision. Also the environmental circumstances have an influence on the risks of leaks.

                                                (Leak Detection Wire)

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FIELD JOINTS INSULATION

Joined bare ends of pipe shall be insulated at site with insulating half – shells.  Jacketing used for protection of insulated joint kits shall be the same materials as of the pipe line jacket

 FITTINGS INSULATION

Fittings may be butt joint or mechanically joined into the pipe line.  Jacketing used for protection of insulated fittings shall be the same material as of the pipe jacket.

                                                (Pre Insulated Fitting)

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THE ADVANTAGES OF GRP & HDPE AS A CORE PIPE

·        GRP & HDPE Pipe is highly resistant to corrosion.

·        No extra joint needed, joint can be provided with locking key system.

·        Lightweight and easy to install.

·        GRP & HDPE Pipe is considered as an insulated material.

·        GRP & HDPE Pipe is chemically resistant.

·        It can be easily repaired at site.

·        High value of thermal and electrical insulation, thus special cladding or energy consuming earthing system is not necessary.

·        Lastly, but most important one, is faster delivery schedule.

  FRP PIPES

 As FRP is a composite material, its physical – mechanical properties vary appreciably according to the production technology, type of resin and type and quantity of reinforcement employed.

 The FRP properties are applicable to wide ranges of temperature, depending on the type of resin employed.

In fact, the mechanical behavior of the thermosetting resins does not change appreciably up to temperatures close to the vitreous transition point of the resin, that is to say, the point where the resin passes from a vitreous to a rubbery state.

FRP, like the thermosetting materials we have discussed, has a visco elastic behavior, but this is less accentuated and depends very little on the temperature over quite wide ranges of temperature variations ( up to 70 – 80 deg. C) .

In heat conditioning conduits or overland pipelines for chemicals subject to freezing or increases in viscosity, the high value of thermal and electrical insulation provided by FRP makes any special cladding or energy consuming earthing systems unnecessary.

This material too possesses an excellent impact strength and abrasion resistance.

Hydraulic properties: FRP too, above all when produced on a mandrel, has very smooth running surfaces.  Hydraulic calculations can be done with formulae which take into account the absolute roughness of the pipe wall, such as the formula of Colebrook.

The calculation roughness, taking into account the localized leakages at the joints is normally between 0.05 and 0.10 mm. whether with a new pipe or with pipe at work.

The length of the pipe sections is generally 6 or 12 meters. FRP pipes are available with different jointing systems, either by welding or using adhesives, or with mechanical systems using spigot and socket (bell) joints or sleeves with elasto meter sealing packing. 

Although joints of the first type above do not require special equipment and heat treatment, yet they have to be carried out by skilled personnel.

The mechanical joints with spigot and socket or sleeve and with hydraulic seal provided by elastomer packing, which are generally toroidal ( o rings), make possible an easy and speedy laying of the pipeline with almost complete assurance of a good hydraulic seal both inwards and outwards and high values of pressure.

 Moreover, some manufacturers provide mechanical jointing systems which by means of suitable clamping devices ensure axial continuity of the pipeline and eliminate the risk of separation of the joints and the need for anchorage blocks for lines under pressure.

 FRP too belongs to the class of so – called flexible pipes and therefore requires certain carefulness in the laying bed and lateral supports. 

In addition, owing to their well known light weight – in fact the weight of FRP pipes is from 3 to 5 times lower than the weight of steel pipes and up to 20 times lower than the weight of concrete pipe – and to the ease with which they can be handled, the cost of laying and installing are extremely low whether the pipeline is to be laid above or below ground. 

A full range of specials and fittings with joints of every type is available for frp pipelines

DESIGN WORK

The materials employed shall conform to the specifications of the drawings and / or orders and shall be evaluated on the basis of tests or previous experience of usage.

In view of the great variety of polyester resins and glass reinforcements available on the market, each design should, in theory, be analyzed as an individual case and the most suitable raw materials should then be selected.

 DESIGN CRITERIA

Design work shall take into account the following factors:

 -         Geometric data of the pipe

-         Normal working loads

-         Any accidental loads

 The above factors are essential elements in the designing of pipes quite apart from the structural material employed. The differentiating element lies in the elastic and mechanical properties of the material employed, namely fiberglass reinforced polyester.

 INERTNESS OF THE LAMINATES

Inertness of the laminates depends upon the type of the resin employed and upon the nature of the product with which they have to be in contact. Deterioration of polyester resins may, in general, due to three phenomena: 

-         Oxidation

-         Specification

-         Solubilization (reduction of the force of cohesion)

 CHEMICALLY RESISTANT PLY

Besides providing tightness this ply performs the functions of a barrier against chemical attack by the liquid stored on the mechanically resistant structure of the pipe.

 MECHANICALLY RESISTANT PLY

This ensures the stability of the structure of the pipe according to usage conditions for which the pipe has been designed, and at the same time it ensures a working life of some ten years for the pipe.

 OUTER PROTECTIVE PLY

This ply protects the mechanically resistant ply against chemical or physical attack by external sources and against temporary accidental contact with the liquid stored in the pipe in some area.

 STRUCTURAL ARRANGEMENT OF THE WALL

To complete the picture , SPS has deemed its opportune to guarantee its own FRP pipes not only against attack from the inner contents but also against the outside acid environment and against natural deterioration due to weathering by means of a last outer top coat rich in isophthalic or bisphenolic polyester resin containing paraffin and an absorber for U.V. rays. 

GRP MECHANICAL RESISTANCE

Having already about the characteristic of chemical inertness of glass – reinforced plastics, we shall now deal with their mechanical strength properties. 

FRP products can be formed by means of hand lay – up or with more less automated mechanical systems. 

The heterogeneous nature of the systems for manufacturing the material, the ability to vary the ratios between the constituent components while starting with the same elements (polyester resin and glass reinforcement) and lastly the wide within which the quality of processing can vary over a period of time, especially with hand processing, are factors which have always made it very hard to determine the characteristic parameters of the material.

 The values which are commonly encountered in the relative literature and compared with stainless steel are given in the table below; they are mean values satisfactory for first dimensioning and any event is precautionary.

 APPLICATIONS:

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