Production

Extensive testing and quality inspection procedures at FLOWTITE pipe manufacturing sites ensure quality of constituent raw material, process consistency and pipe products. These procedures are maintained by the AMIANTIT Technology Centre.

Raw Materials
Raw materials are controlled to ensure material consistency before use in the production of pipes. Glass fibres, thermosetting resins and silica sand are carefully controlled prior to use in pipe manufacturing process using an array of material testing procedures to ensure suitability for use in the FLOWTITE filament winding process and confirm materials consistency. Testing procedures are often recognised international standards for material control, but also include internally developed testing procedure to confirm material quality, testing includes:

■ Glass fibres – moisture content, sizing content, liner density
■ Silica sand – moisture content, loss on ignition, particle size determination
■ Thermosetting resin – curing characteristics (reactivity and time to gelation), viscosity,

Production control
Many parameters are controlled during the FLOWTITE continuous filament winding pipe manufacturing process to ensure final product quality. Advanced computer-controlled production processes permit on-line, real time process control, in addition to regular monitoring of the production process by trained quality personnel.

After pipe production, each pipe is inspected and controlled by trained operators before pressure testing. This pressure testing, hydrotesting, is typically performed at twice nominal pressure for the pipe and internal pressure is maintained for a period of time and thereafter inspected to ensure leak tightness. The hydrotesting is a non-destructive test and ensures each pipe’s performance under internal pressure before shipment.



Final pipe testing
Regular samples are taken from pipe production and pipe quality is confirmed to meet minimum requirements. Pipes are tested using the following procedures:

■ Inner and outer diameter
■ Pipe wall thickness
■ Initial specific ring stiffness (STIS)
■ Initial specific circumferential tensile strength (hoop strength)
■ Initial specific longitudinal tensile strength (axial)
■ Initial resistance to failure (bore and structural failure) on deflection
■ Pipe composition (glass fibre, resin and silica sand content)

The flexible coupling joint for connection and leak tightness of pipes is also carefully controlled to ensure quality of the finished pipe. Couplings are controlled to ensure that dimensional tolerances are met, and pressure testing is performed to confirm coupling tightness.