Explosives that is pre packaged into plastic, card or paper tubes.

Two or more (straight) lines, (flat) surfaces equally distant from one another at all points.

The PCF tube is a hollow plastic tube, open at one end which can then be filled with the powdered smokeless propellant and then closed with a small cap. The other end is machined into a wedge to lock into the stemming, and to seal the hole when inserted for ignition. In the cap there is an entry port for insertion of an electric match, which is the means of detonation. This heat ignites the propellant. As there are not the crushing effects of compressive breakage as with explosives, dust and fines are significantly reduced. As the rock requires less energy to break in tension than compression, a much smaller energy input is recquired. A 200 g charge of PCF blasts the same volume of rock as does 1.2 kg of explosive charge, whilst releasing one tenth of the energy. The product has been found to be particularly useful in deep South African mines as it’s low toxicity reduces re-entry time in these hard to ventilate mines thus improving productivity by up to 40 % (Minesite News, 2000). Some gas is produced from the combustion of the cartridge, for PCF, the majority of the gases produced are carbon dioxide, water, nitrogen, carbon monoxide and hydrogen. The main problem gases which are detectable are carbon monoxide, and nitrous oxide which also occurs at low levels. The addition of a very small amount of ANFO prill does increase the toxic fumes from the product, but still below minimal levels in modern ventilation systems. This gives the product a little extra power to fragment the rock. The product also has the ability to enable users to have more control over the accuracy of the excavation profile and drive perimeters. PCF has also been used in floor stripping, back stripping and side wall stripping in a number of mines in Australia, particularly when a larger equipment size is required and minimal disruption to underground operations is essential. By altering the position of the charges in the holes the products flexibility allows for the rock to be fractured or split. PCF can also be used for the clearing of block grizzlies, crushers or chutes, or anywhere else where oversize is a problem.
The classification for PCF is 1.4S pyrotechnic, as an added safety precaution, the electric match used for detonation is inserted right before firing.

The rate at which a particle of ground is moving, i.e. a measure of ground vibration, in millimetres per second.

Pentolite is a high explosive used for military and civilian purposes e.g. warheads and booster charges.

Military pentolite comprises a mixture of 50% PETN and 50% TNT. A 50:50 mixture has a density of 1.65 g/cm3 and a detonation velocity of 7400 m/s. Civilian pentolite sometimes contains a lower percentage of PETN. Civilian pentolite has a detonation velocity of approximately 7,800 metres per second.

A perforating charge is a type of shaped charge used in the well industry to perforate casings and allow fluids to flow into the well.

A perforating charge is assembled from four components: case, main explosive pellet, primer, and liner.

When the explosives detonated the metal liner collapses into a high speed jet that perforated the well lining.

A perforation in the context of oil wells refers to a hole punched in the casing or liner of an oil well to connect it to the reservoir. In cased hole completions, the well will be drilled down past the section of the formation desired for production and will have casing or a liner run in separating the formation from the well bore. The final stage of the completion will involve running in perforating guns, a string of shaped charges, down to the desired depth and firing them to perforate the casing or liner. A typical perforating gun can carry many dozens of charges.

 Commonly, perforation guns are run on E-line as it is traditional to use electrical signals from the surface to fire the guns.

A perforation in the context of water, oil and gas wells refers to a hole punched in the casing or liner of an oil well to connect it to the reservoir. In cased hole completions, the well will be drilled down past the section of the formation desired for production and will have casing or a liner run in separating the formation from the well bore. The final stage of the completion will involve running in perforating guns, a string of shaped charges, down to the desired depth and firing them to perforate the casing or liner. A typical perforating gun can carry many dozens of charges.

Commonly, perforation guns are run on E-line as it is traditional to use electrical signals from the surface to fire the guns. In more highly deviated wells, coiled tubing may be used. Newer technologies allow the guns to be run on slickline. Modern slickline technology embeds fiber optic lines that can transmit two-way data on real-time temperature, pressure and seismic responses along the length of the slickline. This information allows very precise operations of various down hole tools, including perforation guns.

The benefit of this strategy is greater deal of control of the well. Casing the bottom of the hole allows the well to be completed without having to worry about reservoir fluids. It also allows precise selection of where in the formation production will be and to be able to seal off perforations, which are no longer useful or counterproductive, through cementing or straddling.

The disadvantage is that perforating can lead to "skin damage", where debris from the perforations can hinder productivity of the well. In order to mitigate this, perforating is commonly done underbalanced (lower pressure in the well bore than in the formation) as the higher well bore pressure will cause a surge of fluids into the well at the point of perforating, hopefully carrying the debris with it. Other methods of stimulation such as acidising and proppant fracturing are often required to overcome this damage and bring the well up to its full potential.

Casing and perforating as a method of completion is common place nowadays, though in some unconsolidated formations, prone to production of sand ( BP Harding as an example), open hole completions, using only sandscreens, may be the preferred choice.

Oil Well Perforation may be basically classified in two types a) Over-balanced Perforating and b) Under-balanced Perforating. Overbalanced perforating is normally carried out with the help of Perforating Guns or Hollow carriers. In Over -balanced Perforation the weight of the Well-bore Column is more than the Reservoir Pressure, thus it normally, ensures that the Well does not start flowing oil or Gas immediately after Perforation. However, it may have the effect of damaging the formation due to forced entry of well-bore fluid (mud) into the reservoir.

The techniques involving drill holes around or on the perimeter of an excavation, generally closely spaced, with the purpose of providing a predetermined face.

A decoupled packaged explosive often traced with detonating cord for presplit and smoothwall blasting in hole diameters between 32mm and 127mm diameter.