2018 Las-Vegas : Polyolefin pipes in the middle east- today and tomorrow
Author(s) : Robert Lawrence, Mohana Murali
The paper covers the growth of the polyethylene pipe sector in the Middle East from the 90s to the present. The initial slow uptake was related to ignorance of the material properties from the end users through to designers and installers. Recently the Middle East has become a world leader in the use of ever larger...
2014 Chicago : Butt Fusion in Logistically Challenging Jobsites
Author(s) : Jason A. Lawrence
Traditional butt fusion technology relies upon high power electrical sources such as power grids or site generators to provide the power for facing operations, heating operations, and the required machine movements. Some jobsites, however, pose special challenges, such as remote location and the lack or unreliability...
2004 Milan : Resistance of PVC-U and PVC-M to Cyclic Fatigue
Author(s) : Whittle, Teo
PVC-U and PVC-M pipes may be used in applications where they are subjected to cyclic
pressures generated by the operation of pumps and valves. It is therefore important that the
pipe material’s response to cyclic loading is quantified and that pipelines are designed and
operated within the material’s established...
2001 Munich : Measurement of Scores and Scratches on PE Pipes used in No-Dig Operations
Author(s) : Stokes, Potter, Muhl, Acland
Research indicates that the scoring of polyethylene pipes that can occur during directional
drilling operations in clay soils will not exceed the specification of 10% pipe wall scoring
depth. However, a higher level of damage may occur in different types of soils from these
operations. Further investigations from...
2001 Munich : Optimising the Performance of Ferrule Straps with PVC Pipes
Author(s) : Stokes, Potter, Metcalfe, Bowman, Graham
The response of three different forms of polyvinyl chloride (PVC) pipe has been explored
when the pipes had attached to them ferrule straps. Pipes were subjected to fluctuating
internal pressure (fatigue) loading at 20°C, and the lifetimes, location of any failures and
the types of failures recorded. Tests were made...
1998 Gothenburg : A New Approach to the Instrumented Falling Weight Method
Author(s) : Lawrence, Rasbash, Potter, Teo
Structured wall plastic pipe has been in existence for many years, but there remains a need for
an appropriate method for assessing the durability of their comparatively thin walls in actual
service. In normal operation this has not manifest itself as a problem, but the fact that damage
can be sustained during...
1998 Gothenburg : Dynamic Pressure Testing
Author(s) : Lawrence, Teo, Potter
There is increasing evidence that dynamic testing is a most powerful. if not the only
practical, method of evaluating whole plastic pipe for its long term service potential.
Indeed in some instances this method is used as the primary indicator of performance in
the researcNdevelopmentaI process of these products :...
1998 Gothenburg : Dynamic Test Method for the Evaluation of Butt Welds
Author(s) : Lawrence, Potter, Teo
When butt welds fail in servicc it is normal to find that the initiation site of the fracture occurs
at the point where the roll bead attaches to the main body of the pipe. The ratio of hoop stress
to longitudinal stress for 'thin walled' pipe is approximately 2 : 1 and so it is more likely that
1998 Gothenburg : Product Development Using the Dynamic (Cycle Pressure) Test
Author(s) : Ansell, Lawrence
Recent years have seen the steadily increasing use of thermoplastics for pipes and fittings for
domestic hot and cold water supply and heating installations. Plastic pipe systems, in particular
those that incorporate a push-in design offer considerable advantages over conventional pipe
systems. However, manufacturers...
1995 Edinburgh : Behaviour of notched fatigue data
Author(s) : Lawrence, Potter, Teo
This paper first outlines the case supporting
the use of a fatigue based test method for plastlc pipes.
listing the factors that have to be addressed in its use
and by reference to a large body of other work justifies
its adoption into the pipe industry. It then presents
further evidence that support the case that...
The Developing Market for Plastics Pipes in the Middle East and the Need for the GPPA
Author(s) : Lawrence