The present invention relates to a machine for perforating, in the transverse direction, paper webs, such as toilet paper and household paper, and webs of similar material. The main object of the invention is to provide a machine which is simple and safe in its construction and which operates at a very high accuracy and further ensures a perforation without causing any noticeable wearing of the parts of the machine involved in the perforation. The object aimed at has been achieved by shaping the...

A perforation device for making roll of plastic bag with an opening and a perforation line on each bag, comprising a cutting unit, an anvil unit and a expanding board, wherein, the cutting unit involves a main unit whereto are fitted with a toothed blade and a specified number of compressing blocks, the expanding board serving to expanding the material bag, the toothed blade on the cutting unit serving to cut and punch a surface of the material bag, making a roll of plastic bags each having an o...

The present invention relates to perforation device for the manufacture of a perforated nonwoven material, whereby a prebonded nonwoven with embossing points is guided to a nonwoven perforation device, needles of a needle roller engage into the prebonded nonwoven and perforate it, and the perforated nonwoven material then undergoes further processing. A ratio is set between the number of needles to the number of embossed points of between 0.15 and 0.25 and a ratio of hole size to embossed point ...

A method for providing a running web with a perforation pattern fitting into printed image units successively printed on the web. The method includes the steps of performing a longitudinal perforation in a separate longitudinal perforator and performing a transverse perforation in a transverse perforator, wherein the perforation is divided to be carried out by a plurality of separate units. The pitch of the transverse perforation rows in the longitudinal direction of the web is controlled by cha...

In a well that opens into an unconsolidated reservoir formation through a perforated portion of grouted casing, the effective permeability is increased by flowing acid through the perforation tunnels to form channels between the grouting material and the reservoir formation and, while maintaining a fluid flow rate that keeps the channels free of solid particles inflowing a sand consolidating fluid that converts the walls of the channels to structures that are integral and permeable.

A film perforation sensor assembly is provided for determining the extent of film movement as film is advanced following an exposure to locate a new film frame in the exposure aperture of an automatically operated, electrically powered still camera accepting a film cartridge containing film having a single perforation proximate each film frame. To improve the sensitivity of the sensor assembly, a movement multiplier is provided to control actuation of a motor energizing circuit so that film is a...

A perforation gun includes an external gun barrel in the interior of which perforators are located which can be ignited via a fuse extending through the gun barrel and which, after ignition, pierce the gun barrel with perforation holes. A sliding tube or a swellable two-component foam is provided which automatically closes the perforation holes. The swellable two-component foam can be provided in a cartridge located inside the gun barrel and can be broken up by the ignited fuse, thereby allowing...

A camera for edge-perforated film with a film feed device (9) and a rotatably mounted film perforation wheel (sprocket wheel) (101) that engages with teeth (102) in the edge perforations of the film and executes a rotational movement during feeding of the film is designed so that one side of the sprocket wheel (101) rests against a bearing surface (17) of a housing part (2) and the other side of the sprocket wheel has a coaxial bearing collar (103) that is rotatably arranged in a bearing opening...

A wrapper for enclosing an article. The wrapper is wrapped around the article with an overlapping area of the wrapper being sealed. A line of perforations are aligned in a fixed position relative to the overlapped area so that lateral pressure applied to either side of the perforation line tears the wrapper at the perforations. Preferably, the lower one of the overlapped portions of the wrapper has a cut extending from the side to facilitate separation of wrapper about a tear line.

A machine and method to operate the machine to provide a plurality of valve-like perforations in the rubber-like backing of a nap mat or carpet by delivering the nap map or carpet to and under a spiked roll. The machine includes a back up roll with grooves therein which prevents grooving of the conveyor belt by the pins or spikes on the spiked roll.