JPH07112895A - Elevation device for attaching and detaching main bearing cap in internal combustion engine and method for removing said cap - Google Patents

Abstract

PURPOSE: To simplify attachment and detachment of a main bearing cap to shorten time required for attachment and detachment of the main bearing cap and to provide excellent work procedure from the viewpoint of safety. CONSTITUTION: This elevating device has a support rail 10 fitted between two transverse stiffeners of a frame box of an engine, and a tackle 24 longitudinally movable on the rail between a position close to the transverse stiffeners fitted with a main bearing cap, and a position facing an inspection opening. After lifting and detaching the bearing cap 4, the tackle 24 is moved together with the vertically suspended cap into the position facing the inspection opening. The cap can be lifted and moved by one tackle in a completely satisfactory manner in regard to safety.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a main bearing cap for an internal combustion engine, especially a large two-stroke crosshead engine,
A lifting device for attaching to and removing from
A suspension member for attachment to an engine, a tackle for attachment to the suspension member, and a tackle chain or wire attached at one end to a main bearing cap,
Lifting equipment.

[0002]

BACKGROUND OF THE INVENTION Main bearing caps for two stroke diesel engines are very heavy, for example MAN B
With the & W 90MC type engine, it reaches 1600kg. When assembling the engine, the bearing cap must be in place and must be removed and repositioned for inspection, maintenance and repair work.

The main bearing is mounted on the bed plate of the engine between the two crank throws and below the lateral stiffener separating the two cylinders from each other. The stiffener provides the bedplate and the frame box of the engine with the rigidity necessary to absorb the forces transmitted from the main bearings to the bedplate.

Removal of the main bearing cap has traditionally been accomplished by attaching a flexible wire to a vertical lateral stiffener or crosshead shoe on either side of an intermediate wall, followed by two flexible tackles with wires. This was done by attaching to each of the wires and attaching the free end of the tackle wire to the bearing cap. The bearing cap is then lifted from the bearing stud by simultaneously operating the two tackles, and after the cap is lifted from the bearing stud, the wire extending in the longitudinal direction of the engine is placed on the side of the frame box opposite the inspection opening. It is attached to the bearing cap so that it can be pulled longitudinally into position in the engine, while at the same time loosening the wire on the other side of the intermediate wall. In order to pull the bearing cap out of the opening, a fourth wire must be attached to the bearing cap, then removed from the opening and placed on the floor. In the prior art, this requires a lot of effort. It typically takes a few people about 10 hours to remove and reattach the main bearing cap. In particular, in the untimely inspection of marine engines, this time-consuming task is very time consuming because the time at the port is often less than the total working days required to work with this prior art technique. It is troublesome. Moreover, the oblique lifting device required to move the bearing cap to and out of the opening is not suitable from a safety point of view.

[0005]

It is an object of the present invention to reduce the time required for implementation and to simplify the removal and installation of the main bearing cap so as to provide an excellent work procedure from a safety standpoint. is there.

[0006]

To this end, in a lifting device according to the invention, the suspension member comprises a support rail for mounting between two lateral stiffeners of an engine frame box and the tackle comprises a rail. Above, it is characterized in that it is movable in the longitudinal direction between a position near the lateral stiffener to which the main bearing cap is attached and a position aligned with the inspection opening.

This allows the tackle to be accurately controlled when the tackle used to lift the bearing cap is mounted longitudinally movably on the support rail. One tackle is sufficient because the tackle is positioned well above the main bearing when the bearing cap is lifted from the bearing studs and can be precisely controlled by such a well-defined lifting device. After the cap is lifted from the bearing stud, it can be easily moved in the longitudinal direction of the engine by moving the tackle in the longitudinal direction of the rail until the suspended bearing cap is positioned against the opening. This can be done entirely without any actuation of the tackle itself. This means that the conventionally known cooperation of loosening and tightening the two tackles does not take place, meaning that longitudinal wires are no longer required.

In another embodiment of the lifting device according to the invention,
The tackle is supported by a member mounted on the support rail so as to be movable in the longitudinal direction and restrainable.

This allows the tackle position to be locked against the opening with respect to the suspended bearing cap, which improves removal safety and allows the tackle to slide on the rails. Allows the bearing cap to be slanted through.

In an embodiment of the lifting device according to the invention, which is simple from a manufacturing point of view, the movable member consists of two plates which are parallel to each other, one end of which is interconnected by a transverse rod. On this rod there is mounted an engaging member provided on the tackle, said plate being at its other end at least one for engaging guides for chains or wires and supporting surfaces of the rails. Support the rollers.

Since the guide body is positioned at one end of the member, the wire lifting position can be positioned in the immediate vicinity of the intermediate wall so that the lifting force of the bearing cap becomes substantially vertical. In addition, the member is positioned a large distance such that the guide projects outside the roller below the lower end of the lateral stiffener of the engine frame box, and the bearing cap when the member is moved to one end of the support rail. It may be designed to be positioned vertically above the lifting point of the. In such a case, the lifting force of the bearing cap acts vertically. The use of rollers reduces the friction so that the tackle can be easily moved between the desired positions.

In a preferred embodiment of the lifting device according to the invention, the support rail is an I-shaped cross-section rail, the inside of the lower flange constituting the support surface, on which the roller provided on the member is mounted. A cutout is provided to allow passage, and the parallel plate has a rod at a distance from the engagement member that is below the lower flange when the chain or wire is under tension. Abut the side.

This has the advantage that the support rail, the moveable member and the tackle can be individually attached to the engine prior to lifting the bearing cap. Thus, the weight of the manually lifted component for mounting the lifting device is kept low, and therefore
You can work alone.

In another embodiment of the lifting device according to the invention,
The tackle is swingable about an axis extending parallel to the longitudinal axis of the rail, and preferably the rail itself is swingably mounted on the lateral stiffener of the engine frame box.

As a result, the bearing cap is removed from the inspection opening without the risk of the chain or wire vibrating violently out of engagement with the chain wheel of the tackle, which would occur if the tackle were pulled obliquely. be able to.

If the engine is a crosshead V-engine with two rows of cylinders, the support rails are advantageously permanently in the engine frame box approximately midway between the two rows of cylinders. Once attached, the tackle can be removably attached to the rail or a member attached to the rail. In V-engines, the guide planes are inclined with respect to the vertical direction, so that between the two innermost guide planes of two cylinders laterally positioned next to each other, there is support during manufacture of the engine frame box. There is a free space where the rails can be permanently attached. Therefore, it is not necessary to attach or detach the support rail each time the bearing cap has to be lifted.

A permanently mounted support rail can be rockably supported by the frame box of the engine, but preferably the support rail is tubular with a circular cross section and the tackle or member is above the rail. These rollers are characterized in that they are supported by traversable hourglass-shaped rollers, which allow the tackle to oscillate freely around the longitudinal axis of the rail and adjust to the tension of the wire or chain. it can.

The present invention further relates to an internal combustion engine, especially a large engine.
A method of removing a main bearing cap of a stroke crosshead engine, wherein a suspension member is mounted in the engine, a tackle is mounted on the suspension member, and the tackle is positioned near a lateral stiffener of an engine frame box. In this state, one end of the tackle chain or wire is attached to the main bearing cap, and after lifting the cap from the bearing stud, move it a predetermined distance in the longitudinal direction of the engine and remove it from the inspection opening. After lifting, the tackle is moved together with the suspended cap to a position approximately in the center between the lateral stiffeners, and then the cap is removed from the inspection opening.

Moving the joint between the cap and tackle in the longitudinal direction of the engine means that the bearing cap is suspended straight down by the wire or chain of the tackle during movement, so that one person can It means that the position can be fully controlled in a very simple way by pushing the tackle forward or backward.

Therefore, the entire work can be carried out in a considerably short time and with little effort, and the bearing cap, which can be lifted freely, can be completely handled from the side of the intermediate wall on which the lifting device is mounted. Moreover, the risk of the bearing cap hitting something accidentally and thus damaging it is reduced.

When taken out, the tackle can swing about an axis extending parallel to the longitudinal axis of the suspension member.

The suspension members, tackles, and chains or wires, and the longitudinally movable members can be individually attached and detached to allow a single person to perform all tasks.

An embodiment will be shown in which the present invention saves a lot of time and enhances safety.

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 shows the area directly above the crankshaft of a large two-stroke crosshead engine with a lateral stiffener 1 separating the individual cylinders. Lateral stiffeners are welded frame sections or, as shown,
It may consist of a single layer through-going plate wall with associated stiffeners. A guide plate 2 is positioned on the transverse plate wall 1 for guiding the associated crosshead. The crosshead is connected to the crank throw 11 via a connecting rod, the associated crank journals being mounted on their respective main bearings 3.

The main bearing 3 has a main bearing cap 4, which is attached to a related lower bearing part formed on the bed plate with a vertically extending bearing stud 5 and a hydraulically tightened nut 6. There is. The lateral stiffener has a recess 7 opposite the main bearing, which is bounded laterally by a stay bolt tube 8 and upwards at the lower end of the guide plate 2.

The lifting device 9 has a suspension member in the form of a support rail 10. The length of the support rails 10 is adapted to the distance between the lateral walls 1 so that the supporting rails 10 extend from one of the lateral walls 1 to the other while being mounted. In the illustrated embodiment, the rail 10 has an I-shaped cross section, the lower flange 16 forms an upward bearing surface, and a notch 17 is provided at one end of the lower flange. Each end of the support rail 10 has a plate 1
An attachment means such as 2 is arranged. These plates are provided with holes.

If the bearing cap 4 has to be lifted, the rail 10 is first inserted through the inspection opening and placed in position above the crank throw 11 at right angles to the lateral stiffener. To do. Then
Raise the rail 10 upwards until the holes in the plate 12 align with the corresponding holes 13 in the lateral stiffener 1. Then
Hold the rail 10 with studs 14 for vertically mounting the rail inserted into the associated holes from the other side of the intermediate wall. The stud has a small diameter protrusion 14a that fits into a hole in the upper end of the plate 12. Then, in order to prevent the stud 14 from coming off, the locking means in the form of a locking piece 15 are folded over on the end of the stud behind the intermediate wall. This operation is repeated on the other end of the support rail.

Next, the member 18 is mounted on the rail 10 so as to be movable in the longitudinal direction and restrainable. The longitudinally movable member 18 consists of two plates 19 which are parallel to each other, one end of which is interconnected by a transverse rod 20.
This member comprises a guide body in the form of a chain wheel 21 for a wire or tackle chain 22 and two rollers 23.
Should be supported at the other end and run on the supporting surface of the rail. The member 18 passes the roller 23 provided on the member upward through the notch 17 of the lower flange 16 and moves the roller toward the other end of the rail, thereby moving the rail 1
It is recommended to be mounted on the zero.

As can be seen in the side view, member 18 is half-moon shaped. This provides the plate 19 with sufficient height and thus the plate 19 is strong enough to withstand the heavy loads exerted by the main bearing caps during lifting, and the tackle 24 to the plate 1.
This is so that it can be received between the rod 20 and the chain wheel 21 without hitting the lower side of 9. Furthermore, the half-moon shape reduces the overall height of the lifting device. The tackle 24 is attached to the member 18 with an engaging member such as a hook 25 hung on the lateral rod 20. Guide the tackle chain or wire 22
1, the tackle 24 together with the member 18 is moved to the end of the rail 10 to a predetermined position where the chain or wire is suspended above the fixing point of the main bearing 3 in a substantially vertical direction. The free end of the chain is attached to the bearing cap with a lifting joint 26, which is attached to the cap 4 with a bolt 29 over the center of gravity of the cap.

After removing the nut 6 provided on the main bearing stud 5, the chain 22 is stretched by operating the endless chain 30 which can operate the tackle wheel with a suitable gearing. The cap 4 is lifted off the bearing stud 5 and the movable member 18 with the cap 4 suspended is moved to a predetermined position aligned with the inspection opening. Here, the tackle position is locked by a locking means such as a locking screw 28. The locking screw is inserted into the screw hole of the plate 19 and screwed until it abuts the web plate of the support rail 10. The wire or chain sling is passed through the inspection opening from the outside and fixed to the cap to remove the cap laterally. When this wire is pulled, the entire rail swings about the lateral stiffening stud 14 and the cap 4 is removed through the opening by loosening the tackle 24 and placed on the floor. If the cap is to be reattached, the above procedure is reversed.

When tension is applied to the chain 22, the tackle 24 is kept at a predetermined distance from the lower flange 16 by the rod 27 positioned at a short horizontal distance from the rod 20. This is because the downward pull on the outside of the chain wheel 21 is positioned on the opposite side of the roller 23 with respect to the rod 20. Thus, the downward pull acts on the plate 19 with a predetermined torque that pushes the rod 27 upward to abut the underside of the lower flange 16. If it is desired to reduce the force required to move the tackle, rod 27
Is preferably rotatably supported on the plate 19 or surrounded by a pipe acting as a roller.

If the holes in the lateral wall 1 are reasonably small, then bolts may be used in place of the studs 14 and the wall and plate 1
After being inserted into the two associated holes, it may be locked with a nut.

In addition, rails 10 may be used, for example shaped like a square box-shaped cross section, in which case the plate has a height that allows the rollers 23 to contact the upper side of the rails.

In a simpler embodiment of the lifting device, the plate 12 of the rail 10 is pivotally connected to, for example, a square plate piece which fits into a V-shaped support which opens upwards and projects from the lateral wall 1. Is good. As a result, for mounting, the rail 10 need only be lifted above the support and lowered into the support. In this embodiment, there is no need to insert bolts or similar mounting elements into the associated holes, yet the rails are held in place.

Furthermore, the ends of the rails 10 can be arranged on such a U-shaped support provided on the lateral wall 1. In this case, the possibility of rotation of the tackle 24 during lateral removal of the cap through the inspection opening is taken into account or the member 18 is divided into two parts and the first part is moved in the longitudinal direction. Place it on the rail 10 as you like,
The second component is attached to the first component such that it is swingable about an axis extending parallel to the longitudinal axis of the rail.

Further, the rail is tubular, the members extend on both sides of the tube, one or more hourglass-shaped rollers are supported on the upper side thereof, and the tackle chain wheel and mounting means are provided on the lower side thereof. May be. Because tubular rails are heavier than I-shaped cross-section rails, this embodiment is preferably used for V-engines where the rails can be permanently attached to the frame box of the engine, for example by welding.

[Brief description of drawings]

FIG. 1 is a perspective view of a segment of a frame box of an engine equipped with a lifting device according to the present invention.

FIG. 2 is a side view of an elevating device including a movable member.

FIG. 3 is an enlarged plan view of the member of FIG.

FIG. 4 is an enlarged end view of the member of FIG.

[Explanation of symbols]

 1 Lateral Stiffener 2 Guide Plate 3 Main Bearing 4 Main Bearing Cap 5 Bearing Stud 9 Lifting Device 10 Support Rail 12 Plate 14 Stud 14a Projection 16 Lower Flange 17 Notch 18 Member 19 Plate 20 Rod 21 Chain Wheel 22 Wire or Tackle Chain 23 Roller 24 Tackle 25 Hook 27 Rod 28 Locking screw 29 Bolt 30 Endless chain

Claims (10)

[Claims] 1. A suspension device (10) for mounting and dismounting a main bearing cap (4) on an internal combustion engine, particularly a large two-stroke crosshead engine, the suspension member (10) for mounting on the engine. A suspension member (1) having a tackle (24) for attachment to the suspension member, and a tackle chain or wire (22) attached at one end to a main bearing cap.
0) consists of a support rail (10) for mounting between the two lateral stiffeners (1) of the engine frame box, the tackle (24) on which the main bearing cap (4) is mounted. A lifting device for attaching and detaching a main bearing cap of an internal combustion engine, which is movable in a longitudinal direction between a position near the lateral stiffening member and a position aligned with the inspection opening. 2. The tackle is supported on a support rail (10) by a member (18) mounted so as to be longitudinally movable and restrainable. An elevating device for attaching and detaching a main bearing cap of an internal combustion engine according to. 3. The movable member (18) comprises two plates (19) parallel to each other, said plates being interconnected at one end by a transverse rod (20) on which An engaging member (25) provided on a tackle is attached to the plate, and the plate has a guide body (21) for a chain or a wire (22) at the other end thereof.
And supporting at least one roller (23) for engaging a supporting surface of the rail.
An elevating device for attaching and detaching a main bearing cap of an internal combustion engine according to. 4. The support rail (10) is an I-shaped cross-section rail, and the inside of the lower flange (16) constitutes a support surface, and a roller provided on the member is passed through the lower flange. There is a notch (17) that can be
The parallel plate (19) has a rod (27) at a distance from the engagement member (25), which rod comprises
The lifting device for attaching and detaching a main bearing cap of an internal combustion engine according to claim 3, characterized in that when the chain or the wire (22) is under tension, it abuts the lower side of the lower flange (16). 5. The tackle (24) is pivotable about an axis extending parallel to the longitudinal axis of the rail, preferably the rail (10) itself being the lateral stiffener (1) of a frame box of an engine. ) Is swingably attached to the main bearing cap attachment / detachment device for an internal combustion engine according to any one of claims 1 to 4. 6. The crosshead type V-type engine having two rows of cylinders, wherein the internal combustion engine is a support rail (1).
0) is permanently attached to the engine frame box approximately midway between the two rows of cylinders and the tackle (24) is removably attached to the rail or member (18) mounted on the rail. The lifting / lowering device for attaching / detaching a main bearing cap of an internal combustion engine according to any one of claims 1 to 5, wherein the lifting device is attached / detached. 7. The support rail is tubular with a circular cross section, and the tackle (24) or member (18) is supported by hourglass-shaped rollers that can run above the rail. Item 7. An elevating device for attaching and detaching a main bearing cap of an internal combustion engine according to Item 6. 8. A method for removing a main bearing cap (4) of an internal combustion engine, especially a large two-stroke crosshead engine, wherein a suspension member (10) is mounted in the engine and a tackle (24) is on the suspension member. Attached to the main bearing cap with the tackle positioned near the lateral stiffener (1) of the engine frame box and the cap is attached to the bearing stud ( After lifting the bearing cap (4) from the inspection opening, the tackle (24) is laterally moved together with the suspended cap after the bearing cap (4) is lifted from the inspection opening. Move the stiffener (1) to almost the center position and then remove the cap from the inspection opening. Main bearing cap extraction method for an internal combustion engine according to symptoms. 9. The method for removing a main bearing cap of an internal combustion engine according to claim 8, wherein the tackle can swing about an axis extending parallel to the longitudinal axis of the suspension member when taken out. 10. A suspension member (10), a tackle (24),
Method for removing a main bearing cap of an internal combustion engine according to claim 8 or 9, characterized in that the chain and the wire (22) are individually attached and detached.