Abstract:
In a pull through doctor blade transfer system, blade edge loading is controlled along the sides of the surface being doctored to relieve loading forces and to achieve a gradual feathering of the blade during its initial application.
Abstract:
An apparatus for removing excess steam from an area around a web, such as paper, the apparatus having a stationary vacuum pick-up slot positioned adjacent the web, a steam exhaust pipe leading from the pick-up slot to a vacuum header, an adjustable opening in the exhaust pipe in the vacuum header, facilitating control of the vacuum across the pick-up slot, and a chamber adapted to be heated, the chamber being configured so as to form one wall of the pick-up slot, and means for maintaining a vacuum on the header and the pick-up slot.
Abstract:
A modified double slot impingement nozzle for floater dryers is used to maximum advantage by optimizing the relationships of the spacing between the nozzles and the nozzle lengths for each row of nozzles along the web. The nozzle is also used to advantage by optimizing the slot width of the secondary jet of the nozzle in relation to the slot width of the primary jet.
Abstract:
In a pull through doctor blade transfer system wherein a coiled blade is payed off one rotatable reel while simultaneously being taken up on another rotatable reel, with an intermediate portion of the blade between the reels being supported in a blade holder arranged to apply the blade to a moving surface to be doctored, each reel is driven by a hydraulic motor. In operation, hydraulic fluid discharged from the motor driving the take up reel is fed to the motor connected to the pay off reel. This fluid is pumped to a high pressure by blade induced rotation of the pay off motor, thus creating a braking torque.
Abstract:
Disclosed is an apparatus for providing a shower of fog onto a web or a machine component in contact with a web. The fog, which has a temperature lower than the temperature of the surface of the web or the machine component to be cooled, is applied to the surface and is caused to evaporate by the difference in the temperatures. A supply of dry air is supplied to transport the evaporated fog from the region surrounding the surface to be cooled. Fog may be generated through the use of an air-atomizing nozzle which propels water and compressed air through a small orifice under pressure to create an atomized mist or fog. The fog may also be generated through the use of an ultrasonic transducer which expels fine droplets of water from its surface by means of a high-frequency oscillating transducer motion. In one embodiment, the fog may also be generated in controlled specified quantities locally at each nozzle as required to provide for a controllable fog application rate across the full apparatus width. Alternatively, the fog may be generated at a single source and then supplied to a common cross-machine plenum with the flow of fog to each nozzle location being regulated by a suitble flow control valve positioned at each nozzle location.
Abstract:
Disclosed is a steam-shower apparatus and method including a supply of steam which is fed through a Coanda nozzle and along a path running parallel with one surface of the apparatus. The sheet to which the steam is to be applied runs parallel to this same surface of the machine, but in a direction opposite to the direction of the flow of steam. The sheet travels along a path spaced slightly from the surface of the machine, and the flow of steam runs the entire length of this surface heating the sheet as it flows in the opposite direction. The apparatus may be divided into several sections so that the sheet may be profiled along certain regions which are defined by these sections. In addition, means are included for altering the volume of flow to any one of the particular sections.
Abstract:
Method and system for applying steam to a paper forming web for the purpose of heating the web to improve the quality of the paper, and withdrawing steam through the use of a vacuum opposite the steam shower, by the simultaneously controlled removal of steam at equally spaced increments by the use of a computer based control system. The computer based control system includes a selectively actuable stepper motor, to effectuate the simultaneous opening of both the steam valve and opposing withdrawal means valve. The system includes a coanda nozzle to cause steam to travel between the sheet and the adjacent surface of the apparatus in a direction opposite to the direction of travel of the sheet and also includes steam impingement nozzles. The apparatus includes devices for creating, housing and providing a supply of steam and a supply of vacuum.
Abstract:
A caliper control system for controlling the thickness and sheet quality of paper passing between calender rolls of a calender stack includes a distribution chamber which houses a supply of heat transfer fluid. A series of nozzles extends across the width of the unit in the cross machine direction, and each of these nozzles are selectively actuable. An actuating means, which may be a piston connected to a solenoid, opens and closes an opening in the wall between the distribution chamber and the nozzle for each nozzle of the unit. In a preferred embodiment, the caliper control system includes two such units. One of these units will supply hot air to the roll surface, and the roll to which the hot air is applied to an unheated roll. The second unit will supply cold air to a heated roll. Each of the nozzles is covered with a plate which includes a large number of apertures for expelling the heat-transfer fluid from the nozzle. The travel of the heat-transfer fluid is such that an impingement flow is created through the apertures. The heat transfer fluid is heated or cooled by a heat exchanger which includes a number of internally finned tubes over which a steam or cold water flow is applied. The air forced through the tubes by a fan is then either heated or cooled.
Abstract:
An apparatus for doctoring a cylindrical rotating surface, comprising a doctor back mounted for rotation about a first axis, and a blade carrier assembly mounted on the doctor back for rotation about a second parallel axis. A doctor blade is removably supported by the blade carrier assembly and is loaded against the rotating surface by a force applied to rotate the doctor back about the first axis. A liquid filled flexible walled tube extends along the second axis between the doctor back and the blade carrier assembly. The blade angle is adjusted by expanding and contracting the liquid filled tube to rotate the blade carrier about the second axis.
Abstract:
A flotation drying system utilizing a nozzle assembly having a mounting system that enables quick assembly and disassembly of the system. The nozzle assembly comprises one or more high pressure supply headers or bulkheads, a nozzle housing extending across the grooved face of the one or more bulkheads in a perpendicular direction to the direction of the bulkhead, the nozzle housing having a port connecting it to the bulkhead so that a stream of air goes through the nozzle housing and is applied to the web for drying. The nozzle assembly comprises sealing plates removably supported by the groove face of the bulkhead adjacent each of the nozzle housings to seal the area between the nozzle housings. A flange extends from each of the nozzle housings over the sealing plates as a means to seal the nozzle housings to the grooved face of the bulkhead. In addition, clamping means are provided adjacent the nozzle housing an on the bulkhead to urge the flange against the sealing plate, and the clamping means places the bulkhead, the nozzle housings and each of the sealing plates in a fluid tight relationship with each other. The clamping means may be provided on one or both sides of the bulkhead, and will generally comprise a clamping support and toggle clamp arrangement.