JPH10176789A - Steam turbine foundation setting method and its bolt structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify frame arranging structure and to rationalize installing work by using a frame buried type length adjustable foundation bolt for adjusting a foundation bolt protruding amount from a base surface on a frame in steam turbine foundation setting. SOLUTION: For setting steam turbine foundation, first a foundation bolt 11 and a pulling-out preventing and bolt length adjusting plate 14 are fixed by screws and then positioning is performed by a template provided for level adjusting of the foundation bolt or the like while a pipe 16 is fitted around the foundation bolt 11. After the positioning, concrete is executed, but concrete sticking to the foundation bolt 11 is prevented by the pipe 16. After the concrete execution, level adjusting is performed for a concrete upper surface, but if there is a large difference in relative levels in the foundation bolt 11 and a bolt height is to be adjusted, this height adjusting is performed by rotating the foundation bolt 11 against the plate 14 and advancing the same while engaged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a mounting base for a steam turbine and a method for setting a base.

[0002]

2. Description of the Related Art In a conventional method of installing a steam turbine, a base setting base bolt can adjust the amount of protrusion of the bolt from the upper surface of the base by penetrating a base.

[0003] In addition, for a portion where a penetrating bolt cannot be used due to the gantry structure, a notch is provided at an end of the gantry on the side where the bolt is embedded, and the height of the bolt is adjusted.

[0004]

In the method of setting a foundation bolt for installing a steam turbine, a through-hole type bolt is used in a portion where the amount of protrusion of the bolt from the upper surface of the base needs to be adjusted. The length is longer than the bolt length required for strength depending on the height of the gantry.

Further, in order to avoid interference with the penetrating bolts in the arbor arrangement, a part of the arrangement has been cut, reinforcing bars have been added, and the like.

It is an object of the present invention to simplify the structure for arranging the gantry and to rationalize the installation work by reducing the length of the base bolt for setting the base.

[0007]

SUMMARY OF THE INVENTION Adjustment of the height of a foundation bolt after concrete casting is achieved by employing an embedded foundation bolt capable of adjusting the bolt length.

[0008] The turning work of the bolt is enabled by the cut surface for the knob provided at the tip of the foundation bolt, and the washer used for tightening the bolt and the counterbore of the base to be fixed are formed into a non-circular shape. By welding and fixing the nut to the washer, an effect of preventing bolt loosening due to vibration can be obtained.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows an example of a method of setting a base setting base bolt on a base for a steam turbine. The conventional foundation setting method uses a base penetrating foundation bolt for a portion requiring fine adjustment of the amount of protrusion from the top surface of the base, such as the B1 and B2 portions, and adjusts the installation level of the bases 1 and 2 after adjusting the installation level. After aligning and tightening the heights of 3 and 4, both ends of the bolt and the nut were welded to prevent rotation. (In the case of the B2 bolt, a through-type cannot be used due to the structure of the base, so a part of the base is cut off. The setting was performed in the same way as for the penetration bolt.) Also, the B3 bolt is embedded beforehand at the time of placing concrete, but the embedded side is fixed by welding the bolt and nut in advance, so the base 5 and the equipment leg Adjustment of the projecting amount of the bolt 7 after setting 6 is not possible, but for parts that do not require fine adjustment, change the level during concrete placement (if the installation area of the gantry is large, the level Considering some cases lowered to mount end) was taking amount lugs to generous. However, when using embedded bolts, if the level change between the end and the center of the gantry during concrete placement is very large, there will be a large difference in the bolt installation level, so the level of the concrete upper surface is kept average. Therefore, it was necessary to re-install.

In the present invention, as a method for coping with a large amount of level change at the time of concrete casting, which is particularly likely to occur in the case of a large turbine, and a method for improving the length of a foundation bolt, FIG.
The basic bolt structure shown in Figure 1 is adopted.

The detailed setting method when the present foundation bolt is used is the same as the conventional buried type foundation bolt, in that the foundation bolt 11 has a minimum length necessary for strength and prevents the bolt from being pulled out and adjusting the bolt length. The plate 14 is fixed by screws, and the pipe 16 is attached. Positioning is performed by a template provided for level adjustment of foundation bolts or the like before casting concrete. After the positioning, the concrete is cast, but a pipe 16 is provided to prevent the concrete from being fixed to the base bolt 11 in order to enable the rotation of the foundation bolt 11 after the casting. Also, the foundation bolt 11
Plate 1 to prevent pulling out
4 and a screw provided so as to be fixed to the base bolt 11 and to be adjustable in length. Next, the level of the concrete upper surface after casting is adjusted. At this time, if there is a large difference in the relative level of the foundation bolts 11 (corresponding to all the foundation bolts in FIG. 1), the bolt height from the concrete upper surface is adjusted. Must be adjusted, but the adjustment can be easily made by rotating the base bolt 11. After the concrete upper surface level adjustment and the bolt height adjustment are completed, the base bolt 11 is rotated and positioned so as to set the base 15 so as to satisfy the interval between the tip of the foundation bolt 11 and the upper surface of the base 15, A flat surface is provided at the tip of the upper screw to be used as a grip for turning the bolt.

This is the purpose of thread protection. After the final adjustment is completed, the washer 12 and the nut 13 are attached and tightened. Next, the washer 12 and the nut 13 are fixed by welding in order to prevent the bolted portion from being loosened due to the vibration of the turbine, which is a large rotating device. When the washer 12 and the base 15 are fixed by welding, the base 15 may be thermally deformed when it is fixed by welding. Shall be performed.

[0014]

According to the present invention, the types of use of the foundation bolts can be unified, and a penetrating bolt is not required, so that it is not necessary to use bolts having a length longer than necessary for strength. Also, the arrangement of the reinforcing bars of the turbine mount is facilitated.

Since the bolt height can be adjusted without being influenced by the level change at the time of setting the turbine mount, the mounting of the mount for a large turbine can be rationalized.

Further, when the level of the base surface changes over time, the height of the bolt can be readjusted, so that the resetting can be performed with minimum influence on the gantry side.

[Brief description of the drawings]

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a view showing a frame structure for a steam turbine according to the present invention and mounting of a base bolt when a turbine base is set on the frame.

FIG. 2 is a sectional view of an essential part of a steam turbine foundation to which the present invention is applied.

[Explanation of symbols]

1, 2, 5, 15 ... Turbine base, 3, 4 ... Base penetrating foundation bolt, 6 ... Turbine body leg, 7 ... Embedded foundation bolt, 11 ... Foundation bolt, 12 ... Elliptical washer, 1
3 ... Nut, 14 ... Plate for pull-out prevention and length adjustment, 1
6 ... sticking prevention pipe.

Claims (2)

[Claims] In a steam turbine base setting, a base embedded type adjustable length base bolt is used for adjusting the amount of protrusion of a base bolt from a base surface on a mount. Basic setting method. 2. A base fixing bolt for fixing a base on a steam turbine installation base, wherein an adjusting seat is provided on a bolt embedding side and a bolt is provided on an exposed side screw portion in order to easily adjust the length after concrete casting. A cutting surface for bolt rotation is provided to adjust the amount of protrusion from the top surface of the base, adjustment work can be easily performed, and the shape of the washer and counterbore is non-circular, and the base and the washer are fixed. Bolt structure for steam turbines.