Viscoelastic coatings are often used to protect pipelines in the oil and gas industry. However, over time defects and areas of corrosion often form in these pipelines and so it is desirable to monitor the structural integrity of these coated pipes using techniques similar to those used on uncoated pipelines. A common approach is to use ultrasonic guided waves that work on the pulse-echo princip...

We report results on the synchronization of an organ pipe either by a second pipe or by a loudspeaker, positioned side by side. Classical theory suggests oscillation death for the synchronization of two organ pipes. With our measurements we clearly exclude this scenario. Rather, we identify the aeroacoustical coupling by the oscillating wind sheet at the pipe mouth as the source of a self-regul...

We study the version of the C-PLANARITY problem in which edges connecting the same pair of clusters must be grouped into pipes, which generalizes the STRIP PLANARITY problem. We give algorithms to decide several families of instances for the two variants in which the order of the pipes around each cluster is given as part of the input or can be chosen by the algorithm.

The paper presents research on expedient repairs, including battle damage repair methods of hydro-pneumatic pipes with adhesives. According to analyzed publications concerning battle damage of military equipment, various pipes and lines, which are used in military vehicles and aircrafts, are one of the most often damaged parts during combat operations. During experimental tests, the efficiency ...

Field and Scott Smith [Field, M., Scott Smith, B.H., 1999. Contrasting geology and near-surface emplacement of kimberlite pipes in southern Africa and Canada. Proc. 7th Int. Kimb. Conf. (Eds. Gurney et al.) 1, 214–237.] propose that kimberlite pipes can be grouped into three types or classes. Classical or Class 1 pipes are the only class with characteristic low temperature, diatreme-facies kimb...

The purpose of the air distribution system in a fluidised bed combustor is to provide a reasonably uniform spread of combustion air over the entire horizontal cross-sectional area of the bed. One of the simplest, and hence cheapest, forms of air distributor is the sparge pipe design, in which an array of horizontal pipes is fitted at the base of the bed. Combustion air is then supplied to one e...

The paper sketches KURT, an autonomous robot platform prototype that is able to navigate inside a network of sewage pipes. KURT is a six-wheeled device; it has modular, layered hardware and control architectures. Its sensor connguration consists mostly of stationary and one exible ultrasound sensors and of two inclinometers. In experiments run in a test sewerage system consisting of concrete pi...

1. ABSTRACT It has been about fifty years ago since the first unplasticized poly(vinyl chloride) (uPVC) pipes were installed for use in gas distribution purposes. Currently, about 22,500 km of uPVC is still in use in the Dutch gas distribution network. The pipes were originally designed for a lifetime of 50 years, but due to positive experiences the question arises if (and how long) the lifetim...