Greig, Ewing
# 1982 York
Fracture propagation is a phenomenon in which a long brittle crack runs along the pipeline at high speeds of approximately 350 m/s. More stringent operating and test pressures of larger diameter polyethylene gas pipes have had to be introduced nationally. Full scale tests on 250 mm SDR 17.6 medium and high density polyethylene pipes have been conducted to define safe pressure levels for crack arrest. The arrest pressures were found to be highly temperature sensitive.
Related papers
Author(s) : Ian Aldridge, Declan Robinson, Dave Smart, Chris Reed, Martyn, Greig, Trevor Stafford, David Christie-Lowe, Alec Erskine
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Funded by a UK government “Smart” Award, the authors have researched, and partially developed, a novel concept for temporarily reducing the external diameter of a PE pipe and then allowing recovery to full diameter as a close fit within a host main. The novelty lies in the four-lobed collapsed pipe geometry, which...
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Author(s) : Greig
One of the main design criteria for limiting the operational pressures of polyethylene (PE) gas pipes is its resistance to rapid crack propagation (RCP). Below a critical pressure the crack arrests but above the whole pipeline may be fractured. The paper discusses the critical pressures measured during European and...
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Author(s) : Greig
The catastrophic phenomenon of rapid crack propagation in 250 mm diameter polyethylene pipes has been investigated at a full scale test facility. Tests at +3°C were conducted with pipes, either completely fully of water or containing a small percentage of air. The safe, maximum pressures were measured. Rapid crack...
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Author(s) : Greig
As polyethylene pipes increase in size above 250 mm, the avoidance of high-speed brittle fracture propagation becomes of overriding importance. More stringent operating and test pressures have had to be introduced. A full scale test programme on a variety of pipe sizes is being conducted by British Gas. In this paper,...
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