Flowtite pipe can be produced in diameters ranging from 100mm-4000mm. The dimensions of Flowtite pipe conform to the "B" Series (i.e., outside diameter controlled) of ISO (International Organization for Standardization) 7370. Controlling dimensionally the outside diameter (spigot) means interchangeability may be possible with other pipes produced to the same diameter series. In general, this means ductile iron pipe in diameters through DN 500 (B2 Series) and other GRP pipes in larger diameter (B1 Series). However, the Flowtite continuous advancing winding process allows pipe to be produced to meet any diameter series, internally or externally controlled, without expensive retooling or mold costs.

For example, some Flowtite pipe manufacturers produce pipe with the same outside diameter as PVC pipe (B3 Series) thereby enabling use of fittings designed specifically for this product. Based on typical pressure classes used around the world, Flowtite has developed standard designs to meet two pressure series:

Custom designs to accommodate higher operating pressure - up to 32 bars - are feasible. Higher pressures for small diameter pipes can be accommodated, too. The basis for Flowtite pressure pipe design is the performance requirements of AWWA C950 (latest edition), which stipulates a minimum factor of safety of 1.8 on the predicted 50 year pressure strength of the pipe, and a minimum of 4 for initial burst strength.

Flowtite sewer pipe has been designed to meet the performance criteria established in ASTM D3262 and ISO 10467.

Pipes intended for use in a gravity sanitary sewer system will meet the chemical requirements of ASTM D3262, which includes a minimum long-term deflection (strain) requirement when exposed to 5% sulfuric acid. Other requirements of this specification include axial tensile strength and hydrostatic soundness.

Product Guide - Technical Data

Flowtite pipe is an advanced composite material designed to take advantage of the corrosion-resistant properties of polyester resins and glass fibers.

Diameters (mm)

Small diameter		Large diameter		Very large diameter*
100		300		2500
150		350		2600
200		400		2700
250		450		2800
		500		2900
		600		3000
		800
		900
		1000
		1200
		1400
		1600
		1800
		2000
		2400

* For even larger diameters, contact your closest Flowtite sales office.

Lengths

The standard length of Flowtite pipe is 12 meters for diameters over 300mm. Lengths of 6 and 18 meters are also available. Smaller diameters are only available in 6-meter standards lengths. Flowtite pipe can also be supplied in other lengths for special orders.

Stiffness Classes

Flowtite pipe can be supplied to the following specific initial stiffnesses (EI/D³).

Load Capacity Values

Complete tables for hoop and tensile load capacity are available in the Flowtite Pipe Product Guide.

Pressure

Pressure classes of Flowtite pipe may be selected from the table below. Not all pressure classes are available in all diameters and stiffnesses.

Pressure Class1		Pressure Rating2		Upper Diameter
PN		Bar		Limit, mm
1 (gravity)		1		3000
6		6		3000
10		10		2400
16		16		2400
20		20		1400
25		25		1400
32		32		1400

¹ Flowtite pipes can additionally withstand an increase in total pressure due to infrequent waterhammer equal to 140% of the nominal pressure rating (e.g., PN10 can accommodate a temporary surge pressure up to 14 bar. However, the normal continuous operating pressure should not exceed 10 bar for that pressure class of pipe.)

² Pressure ratings have been established in accordance with the design approach outlined in AWWA M-45, Fiber Glass Pipe Design Manual.

Flow coefficients

Based on tests carried out over a three-year period on Flowtite pipe, the Colebrook-White coefficient may be taken as 0.029mm. This corresponds to the Hazen-Williams flow coefficient of approximately C=150. Head-loss calculation charts are available in the Flowtite Pipe Product Guide.

The Joint: Key to Success for a Piping System

The standard jointing system is a Flowtite® coupling which utilizes an elastomeric REKA gasket for sealing. The REKA gasket sits in a precision-machined groove in each end of the coupling and seats and seals against a calibrated spigot surface. The REKA gasket has been proven in use for more than 75 years.

The joint design has been demonstrated to meet the performance requirements of ASTM D4161 which includes both hydrostatic pressure qualification at two times rated pressure along with negative pressure qualification at -74KPa gauge, both when the joint is subjected to angular deflection or vertical offset. The amount of angular deflection is diameter dependent, ranging from 3.5% down to 0.5%. Contact of the calibrated spigot with the bottom of the coupling bell is achieved in the vertical offset test.

The couplings are produced on the same winder as the pipe, featuring a special design, which facilitates the milling process.

Couplings, too, are produced with tightly controlled dimensions. For this, Flowtite Pipe Technology has developed a special machine which mills grooves in coupling cylinders using diamond-tipped tools.

For proper sealing of the REKA gasket, especially for pressure classes of up to 32 bar, a smooth, dimensionally accurate outside spigot surface is needed on each end of the pipe. Flowtite has developed equipment which chamfers the edge of the pipe to avoid damage to the rubber gaskets, while simultaneously milling the external surface. This equipment rotates the pipe and mills both ends using water-cooled diamond-tipped tools.

Many international and national standards for GRP pressure pipe require the manufacturer to factory hydrotest pipe before shipment. In support of these requirements, we have designed equipment to accommodate hydrotesting of both the pipe and couplings to twice the rated pressure (for diameters through DN3000).

Other Technical Data

Complete listings for the following types of information are available in the Flowtite Pipe Product Guide.

• Leak tightness testing
• Surge pressures
• Strain corrosion performance
• Hydrostatic design basis
• Poisson's ratio
• Water jet cleaning
• Permissible operating temperatures
• Thermal coefficients