In an apparatus for making plastic bags or the like from a continuous film of material comprising a sealing drum having at least one seal bar for imparting transverse seals to the film at regularly spaced intervals and a perforator having a rotatable perforator blade for imparting transverse perforations to the film at regularly spaced intervals, the film comprising print marks appearing thereon at regularly spaced intervals, an apparatus and method are disclosed for tracking the positions of ea...

A perforation detector of a camera comprises a light emitting unit for emitting light to a film, a photo-sensor for sensing reflected light from the film to produce a signal representing a sensed light intensity, the light intensity of the reflected light varying with presence or absence of a perforation at a reflection area of the film, a detection unit for comparing the signal from the photo-sensor with a predetermined value to detect a perforation of the film, and a control unit for controlli...

Method and apparatus for perforating a well casing (14) with a large pressure differential toward the well casing (14) from the surrounding oil and gas-bearing strata using a casing gun attached on a wireline below the tubing is disclosed. A perforator (12) is attached to a casing gun adapter (10), the casing gun adapter (10) is releasably attached to production tubing (16) and inserted into the well casing (14). After the production tubing (16) is installed, a collar locator (26) and a firing m...

Disclosed is a process of minimizing damage of the formation surrounding perforation channels in a subterranean formation during workover and completion operations when the need exists to temporarily seal the perforation channels and subsequently clean them before packing the channels with gravel. The process comprises filling the perforation channels with a water soluble particulate sized salt to form a highly permeable salt pack therein, sealing the salt pack with a low permeability film by tr...

Laser perforation of all types of paper provides paper having sufficient strength characteristics to survive stresses imposed during handling, such as experienced in sheet feed processes. The paper so perforated is readily separable along the perforation line when separation is desired. Carbonless paper products particularly benefit from use of a laser in perforation. The paper, capsule, and capsule fill material are vaporized during the laser process, thus forming clean holes and leaving little...

Filter cigarettes with a predetermined dilution factor are produced by perforating a filter attachment web by means of an adjustable perforating device prior to using portions of the web to join filters to cigarettes; measuring the porosity of the perforated web; measuring the dilution of cigarettes assembled with portions of the web; and controlling the perforating device by immediate response to the measured porosity and by progressive response to the dilution of the assembled cigarettes. The ...

Apparatus is provided to detect a discontinuity indicative of a hole in the bore wall of an axially extending tubular member. It comprises: (a) a carrier to be traveled axially lengthwise in the bore of the tubular member, (b) an acoustical wave transmitter located on the carrier to transmit acoustical waves for travel toward the bore wall and for reflection therefrom, (c) an acoustical wave detector at least partially located on the carrier to receive acoustical waves reflected from the bore wa...

A bursting apparatus for separating sheets in a continuous intermittently perforated form web is disclosed. The apparatus includes a feed roller, a burst roller and a bursting device, said bursting device disposed between said feed roller and said burst roller and comprising two horizontally positioned cone sections wherein their base portions are adjacent to each other and are encircled at least in part by a bursting ring, said bursting ring having a portion extending beyond said cone base port...

A method and apparatus is described for increasing hydrocarbon production from a production well by determining a bedding plane (permeability anisotropy) of a hydrocarbon bearing formation and using a perforating tool to form in the formation holes having an essentially elliptical or elongated cross-section with the longest axis of said elliptical or elongated cross-section oriented perpendicular to said bedding plane (or in direction of the lowest permeability).

A method for predicting perforation corrosion in a hem flange. The method includes placing an electrode in the hem flange. The electrode extends substantially the entire length of the hem flange. An electrolyte is introduced into the hem flange so that the electrode is immersed, and the electrochemical impedance spectrum of the hem flange is measured. The measured electrochemical impedance spectrum of the hem flange can be compared to a reference electrochemical impedance spectrum. A collection ...