Brief Description of the Prior Art
This invention relates to industrial heat transfer equipment which includes a floating head at one of the exchanger. The floating head may be manipulated between closed, or locked, position, to completely open position, for the removal of tube bundles from the shell body of the equipment. There are many types of heat transfer equipment available, however one of the most widely known types comprises a plurality of parallel tubes encased in a relatively close fitting tubular shell. Provisions are made whereby a fluid flows outside the tubes, called the shell-side fluid, and a fluid flows inside the tubes, called the tube-side fluid. Although this tubular type equipment is generally referred to as heat exchangers, depending upon the specific service in which it is employed this equipment may be variously designated as heat exchangers, overhead condensers, surface condensers and vaporizers, etc. As used herein, including in the appended claims, the term “heat exchanger” means all shell and tube type equipment regardless of its specific designation for a particular purpose.
When heat exchangers are utilized under conditions wherein the temperature difference between the tube side and shell side fluids is large it is necessary that the heat exchanger design include means to allow for the difference in expansion of the tubes and of the shell. Various expedients may be employed to accommodate the expansion such as flexible sections built into the shell, U-shaped tubes, and others. Where an exchanger is used in a service which necessitates the removal of the tube bundle in order to clean the outside surfaces of the tubes a “floating head” is used which permits free expansion of the tube's heat yet permits the tube bundle to be removed readily for repairs and/or cleaning.
The removal of the tube bundle becomes necessary when a shell side fluid is used which is dirty or scale forming. The deposition of scale on the outside of the tubes interferes with effective heat transfer and must be removed in order to maintain maximum design efficiency. These scale deposits can be classified as hard, porous, or loose depending upon the nature of the materials forming the deposits. In some instances the scale may be removed by flushing operation or the use of various solvents which cleanse the equipment without the need for removing the tube bundle from the shell. More recalcitrant deposits such as hard deposits formed by water-deposited scale, corrosion products and so forth and even porous deposits formed by mud and dirt, coke and carbon, asphalt and tars which resist the flushing and/or solvent cleaning operations demand the removal of the tube bundle from the exchanger shell in order that the external surfaces of the tubes may be made conveniently accessible for mechanical cleaning equipment. After removing the cover plates of the stationary head or the stationary head if the cover is integral therewith and the tube plate is positioned between the shell and head the entire tube bundle is withdrawn from the exchanger shell by connecting a suitable prime remover to the tube sheet and applying a force sufficient to remove the tube bundle. In the removal of the tube bundle, care must be exercised to prevent injury to the tubes. When large bundles of tubes are badly fouled by scale deposits it is necessary to apply a considerable force to the stationary tube sheet. This resultant force may cause damages to the tube bundle. In addition large bundles of tubes which are not fouled may require a large force to overcome the inertia present and if the entire force necessary to remove the tube bundle is all applied at the tube sheet undesirable consequences may obtain. Thus, removal of the tubes requires a careful operation which includes manipulation of the floating head initially secured onto the shell body for complete removal from the shell body. This has required heavy duty lifting machinery, which may include a crane, which is secured at a point exterior of the floating head. Attention is directed to
A typical prior art device is shown in Chinese patent publication no. CN201867115U. The disclosed device is unable to be used in combination with floating heads of varying sizes such that the resulting positioning of the head when removed from a heat exchanger housing will result in suspension of the device at a pre-selected angle relative to the stable heat exchanger housing.
The present invention provides a lifting device which is selectively installed on the existing lifting lug of the floating head by moving the center of gravity and thus permitting the device to act as a lever, forcing the head to hang, preferably, at a 90 degree angle, so that it can be installed safely and efficiently. The preferred device provides a series of openings to permit the device to be operable with a number of sizes of floating heads It adjust with seven holes that allow it to work with many different size floating heads. The preferred design of the device includes a straight end and another opposite one end that is at a pre-determined angle, such as a 45 degree angle to adjust for the depth of the floating head.
Field of the Invention
The invention is directed to a device for the installation, suspending and removal of a floating head of a heat exchanger body.
The invention provides a device for the manipulation of a floating head between secured and removed positions relative to a heat exchanger housing, and for suspension of the floating head between said positions as heat exchanging tubes are replaced or cleaned. The floating head has holding means such as a ring welded to the exterior thereof for affixation of a lifting member of a lifting means, such as a crane, or the like. The device comprises an elongated body having first and second opposed ends. The body has at least one opening there through for selective receipt of means such as a bolt or lug, for attaching the elongated body to the holding means, whereby when the device is affixed to the floating head, the floating head may be manipulated and suspended at approximately a 90 degree angle relative to the heat exchanger. A spinal projection extends from one end of the device body and is offset relative to the body at a pre-determined angle, such as approximately a 45 degree angle. A securing member is provided on the projection for selective receipt of the lifting member. When secured together, the floating head and the device as described provide a unitary combination for use in removal of the floating head member of the heat exchanger.
Now, with first reference to
Now referring to
As shown in
When it is desired to remove the floating head A to clean or repair the interior of the heat exchanger housing C, the device is moved into aligning position relative to the floating head A by transporting it to said location by means of a hoist or the like. The device 10 may be suspended for transport to the location by placing a bolt or the like through the spine opening 12A so that the device 10 is transported in a vertical position.
Referring to
Concurrently, or just prior thereto, one end of chain CH of hoist H carrying block BK is moved to the head A. The block BK is secured into the receptacle R1 by snapping latch LT into the clasping member R2 of the receptacle R1. The floating head A may now be removed from the housing C from the position shown in