CH716580A2 - Segmented exhaust pipe for a large engine, especially a longitudinally flushed, slow-running cross-head large engine. - Google Patents

Abstract

The invention relates to an exhaust pipe (1) for a large engine, in particular for a longitudinally flushed, slow-running cross-head large engine, comprising a manifold (2) with a plurality of connecting pieces (3) which can each be connected to a cylinder liner for receiving and collecting exhaust gases , and an outlet pipe (4) that can be connected to a turbocharger for receiving the exhaust gases, the exhaust pipe (1) also being connectable via a plurality of flexible supports (5) and at least one inflexible fixing foot (6) for supporting the large engine . According to the invention, the exhaust pipe (1) is designed as a segmented exhaust pipe (1) with a plurality of exhaust segments (21). In addition, the invention relates to a large engine, in particular a longitudinally flushed, slow-running cross-head large engine with an exhaust pipe of the present invention.

Description

description

The invention relates to a segmented exhaust pipe for a large engine, in particular for a longitudinally flushed, slow-running cross-head large engine according to the preamble of the independent claims.

Slow-running large engines, in particular longitudinally flushed large engines of the crosshead type according to the present invention, are preferably used in shipbuilding or in stationary systems, for example for generating electrical energy, for many decades in a large number of different variants in detail.

Such large engines in many cases include three large housing segments that form the frame of the engine. A so-called stand is arranged on a base plate, which has transverse support elements in addition to a bearing saddle with a crankshaft main bearing for receiving the crankshaft, separated by a base plate. According to the number of cylinder liners of the large engine, the known stands comprise several oppositely arranged support bodies, each of which has a perpendicular sliding surface for guiding two adjacent crossheads which are connected to the crankshaft via push rods. A cylinder section, often also called a cylinder jacket, which is suitable for receiving one or more cylinder liners, is then arranged above the stand. The base plate, the stand and the cylinder section are connected to one another by tie rods, which generally extend within the support body in the region of the stand, by screwing the tie rods into or on the base plate with considerable pretension.

In the operating state, the hot exhaust gases are supplied by opening an exhaust valve provided in a cylinder cover of the cylinder liner from the combustion chamber of the cylinder liner via an exhaust pipe to a charging group in the form of a turbocharger, with which fresh air is sucked in and compressed and the individual combustion chambers of the cylinder liner are used as scavenging air of the large engine is fed in via so-called scavenging slots in the lower area of the cylinder liner.

An example of such a large engine is disclosed, inter alia, in CN105545437A.

It is known to operate the engines either according to a diesel process, that is to say as a compression ignition, or according to an Otto process in which the mixture can be spark-ignited in a targeted manner with a suitable ignition source at a suitable crank angle. The fuels used are, for example, heavy oil, diesel, gas or other suitable fuels which are well known per se to the person skilled in the art. Also as so-called dual-fuel engines, which can be operated both with a classic fuel such as heavy oil or diesel and also with a suitable gas as fuel, more and more types of large engines according to the present invention are on the market.

In this case, an exhaust pipe, which is simultaneously connected to several cylinder liners in a manner known per se for discharging exhaust gases from the associated combustion chambers, is usually supported by several flexible supports and a substantially inflexible or fixed support on the engine. The inflexible or fixed support, hereinafter referred to as the fixing foot, and thus also the corresponding add-on parts on the exhaust pipe that connect the exhaust pipe to the fixed support, i.e. the fixing foot, enable safe and reliable positioning of the exhaust pipe in relation to the longitudinal, lateral, and vertical direction. In addition to the effects of the enormous weight of these parts, as well as the static and dynamic effects of pressure fluctuations and vibrations in the exhaust system and the entire engine as such, the structural parts of the fixing foot are mainly thermal loads due to the temperature differences between the hot, insulated exhaust pipe on top of the engine and exposed to the cold, uninsulated fixing foot attached further down on the motor.

The currently common in the prior art designs of the exhaust system described above are based on the principle that the exhaust pipe is first made into a single piece and then, in a second step, the fixing foot is welded to it. The exhaust pipe is embedded in the fixing foot. The fixing foot itself is usually wider than the distance between two adjacent cylinder liners and is very difficult for the welder to weld together.

The object of the invention is therefore to provide an improved exhaust pipe.

The objects of the invention that achieve these objects are characterized by the features of the independent claims.

The dependent claims relate to particularly advantageous embodiments of the invention.

The invention thus relates to an exhaust pipe for a large engine, in particular for a longitudinally flushed, slow-running cross-head large engine, comprising a manifold with a plurality of connecting pieces that can be connected to a cylinder liner for receiving and collecting exhaust gases, and an outlet pipe that can be connected to a turbocharger for receiving the exhaust gases, wherein the exhaust pipe can also be connected via a plurality of flexible supports and to at least one inflexible fixing foot for support on the large engine. According to the invention, the exhaust pipe is designed as a segmented exhaust pipe with a plurality of exhaust segments.

It is therefore essential for the invention that the exhaust pipe is designed as a segmented exhaust pipe with a plurality of exhaust segments.

The exhaust segments are particularly advantageously welded together to form the exhaust pipe in the form of a long pipe. In very special cases, it is also possible that the exhaust segments in other, the specialist

Claims (4)

are connected to each other in a known manner. The fixing foot can particularly preferably be arranged in the area of the center of the exhaust pipe, as will be explained in more detail below. The invention further relates to a large engine, in particular a longitudinally scavenged, slow-running cross-head large engine with an exhaust pipe of the present invention. By the present invention, the one-piece exhaust pipe known from the prior art is newly provided as a segmented exhaust pipe, which is particularly preferably constructed from individual exhaust segments, the length of which corresponds approximately to the distance between two adjacent cylinder liners. These exhaust segments are then welded together in the form of a long pipe. The fixation foot is best made in the form of a modular design, which also has approximately the length of the distance between two adjacent cylinder liners. This design of the exhaust pipe or the fixing foot of the present invention is more accessible for the welding work and is easier to manufacture than the previously known designs. In addition, with the new design it is possible to provide an exhaust gas cone towards the turbocharger in the area of the fixing foot, which was not possible with the previous known embodiments. Using special welding techniques, it is possible that all modules of the entire exhaust pipe, including the fixing foot, can be welded in a particularly stress-free manner, with a minimum of deformation, in particular with regard to the longitudinal direction. The fixing foot particularly preferably comprises three strong vertical plates which are welded to a bottom flange. The two lateral plates form the end of the module and extend to the bottom flange with which they are welded. The third plate is a strong floor batten that extends longitudinally between the two aforementioned plates and laterally approximately in the middle of the exhaust pipe. It is also welded to the bottom flange. While the last-mentioned plate absorbs all longitudinal forces and is flexible in the lateral direction, the first-mentioned two plates absorb all longitudinal forces and are preferably flexible in the lateral direction. The longitudinal direction is the direction in which the strong thermal expansion of the exhaust pipe takes place. In order to minimize possible longitudinal movement of the exhaust pipe in the unlikely event of a complete failure of the longitudinal plate of the fixing foot, the fixing foot is particularly advantageously provided approximately in the middle of the exhaust pipe so that it is always surrounded by at least one flexible support . The invention is explained in more detail below with reference to the drawing. They show in a schematic representation: FIG. 1 schematically an exhaust pipe with flexible supports and a fixing foot; FIG. 2 shows the exhaust pipe according to FIG. 1 in a perspective view from a view opposite to FIG. 1. The exhaust pipe 1 for a large engine, in particular for a longitudinally flushed, slow-running cross-head large engine, according to Fig. 1 or Fig. 2 comprises a manifold 2 with a plurality of connecting pieces 3, which can be connected to a cylinder liner for receiving and collecting exhaust gases are. The connecting pieces 3 cannot be seen in FIG. 2 because, from this perspective, they lie on the opposite side of the exhaust pipe 1 that is not visible in FIG. 2. Furthermore, two outlet pipes 4 are provided on the exhaust pipe 1, which in the installed state are each connected to a turbocharger for receiving the exhaust gases. As can be clearly seen, on the exhaust pipe 1 there are also a plurality, here three flexible supports 5 approximately in the middle of the exhaust pipe, as well as a much less flexible fixing foot 6, here referred to as an inflexible fixing foot 6 for the sake of simplicity, to support the large engine, not shown intended. According to the present invention, the exhaust pipe 1, as can be clearly seen, is designed as a segmented exhaust pipe 1 with a plurality of exhaust gas segments 21, which in the present specific exemplary embodiment are not all of the same length. In practice, in other exemplary embodiments of the invention, it is particularly advantageous if most or all of the exhaust gas segments 21 have the same length, which particularly preferably corresponds approximately to the distance between two adjacent cylinder liners. The exhaust segments 21 are here welded together to form the exhaust pipe 1 overall in the form of a long pipe. The person skilled in the art understands that the invention is not limited to the exemplary embodiments discussed explicitly, but that corresponding developments are also covered by the invention. In particular, of course, the invention relates to all suitable combinations of the specific embodiments discussed. Claims 1. Exhaust pipe (1) for a large engine, in particular for a longitudinally flushed, slow-running cross-head large engine, comprising a manifold (2) with a plurality of connecting pieces (3) which can each be connected to a cylinder liner for receiving and collecting exhaust gases, as well as an outlet pipe (4) which can be connected to a turbocharger for receiving the exhaust gases, the exhaust pipe (1) also being connectable via a plurality of flexible supports (5) and to at least one inflexible fixing foot (6) for supporting on the large engine, thereby characterized in that the exhaust pipe (1) is designed as a segmented exhaust pipe (1) with a plurality of exhaust segments (21). 2. exhaust pipe (1) according to claim 1, wherein the exhaust segments (21) are welded together to form the exhaust pipe (1) in the form of a long pipe. 3. Exhaust pipe (1) according to one of the preceding claims, wherein the fixing foot (6) can be arranged in the region of the center of the exhaust pipe (1). 4. Large engine, in particular longitudinally flushed, slow-running cross-head large engine with an exhaust pipe (2) according to one of the preceding claims.