US1338409A - Steam-turbine - Google Patents

Description

C. R. WALLEH.

STEAM TURBINE.

APPLICATION FILED OCT. 1. 1919.

Patented Apr. 27, 1920.

UNITED sTATns PATENT onmon.

CARL R. WALLER, F TRENTON, NEW JERSEY, ASSIGNOR TO BE LAVAL STEAM TURBINE COMPANY, OF TRENTON, NEW JERSEY, A CORPORATION OF NEW JERSEY.

STEAM-TURBINE.

Specification of Letters Patent. Patented: Apr, 2'7, 1920,

Application filed October 1, 1919. Serial No. 327,651.

To all whom it may concern:

Be it known that I, CARL R. WVALLER, a

citizen of the United States, residing at turbine.

It is also a practice to make the steam admission at the two extreme ends of the turbine casing, allowing two sets of wheels to utilize a common exhaust. This design is undoubtedly preferable where a single turbine is utilized, but if a compound turbine is used, and if reversing elements must be provided in both the high and low pressure turbine, provisions are made to keep the exhaust of the high pressure ahead turbine separated from the exhaust of the high pressure astern turbine. The object of my invention is to improve the construction of this type of turbine. The nature of the improvement will be clear from the subjoined description of the preferred embodiment of the invention shown in the drawings, in which Figure 1 is a sectionalview of a portion of a high pressure steam turbine embodying my invention.

Fig. 2 is a cross-section taken on the line 2 2 of Fig. 1.

The turbine case is made in three semicylindrical sections,'two end sections a and Z) and an interposed connecting section 0. The section 0 has an inwardly projecting steam chest (Z for (say) the reversing The turbine cover is made in three similar semi-cylindrical sections,-two end sections 0 and f and an interposed connecting sec tion 9. The section 9 has an inwardly projecting semi-annular steam chest 72. for (say) the ahead turbine.

By making section 0 (Z separate from sections a and b, they can be made of different material from sections a and b; that is, of

metal more suitable for high pressure steam. For the same reason, section 9 It is made separate from sections 6 and f.

In assembling, the turbine section 0 (Z is securely bolted to sections a and 6, these three sections being subsequently handled together and forming the case as: distinguished from the cover. Section 9 h is similarly bolted to sections 6 and 7, these three sections forming the cover, which is also handled as a unit. The-cover is placed upon the case in such position that the steam chests d and h form diametrically opposite walls dividing the turbine into two chambers; one chamber containing the ahead turbine wheels, the first of which isshown at i, and the other chamber containing the astern turbine wheels, the first of which is-shown at j.

When the turbine is running ahead, pressure in the chamberin which wheel 2' revolves will be higher than the pressure in the chamber in which wheel j revolves. Due to this difference in pressure, steam tends to leak along the shaft 70 from the higher pressure to the lower pressure side. prevent this, stuffing boxes m, m are provided. A bleed-off connection n is provided from the chamber that is formed between the stufi'mg boxes.

0 is a maneuvering valve having one steam inlet and two steam outlets, the two steam outlets being connected respectively to the ahead chamber l1. and the astern chamber 05, the valve being operable to admit steam to either chamber.

I am aware that it is old to provide a partitiondividing a turbine into an ahead portionand an astern portion with nozzle boxes or steam chests communicating with the respective chambers. In such constructions the steam chests are either arranged in different planes perpendicular to the turbine shaft; or the partition itself comprises two segmental sections located in different planes perpendicular to the turbine shaft so that the two chambers overlap; or each steam delivery is formed in a semi-annular ring chest secured to the single casing or cover common to the ahead and astern compartments, which are separated from each other by a dummy piston mounted on the shaft and semi-annular partitions within the ring section. In my construction, the steam chests are not in the respective chambers of the turbine on opposite sides of a partition, or in semi-rings secured to a single-piece casing or cover, but themselves form the dividing wall between the two chambers of the turbine.

This arangement is made feasible by making one steam chest an integral part of the central portion of the cover and the other steam chest an integral part of the central portion of the case; these central sections being made separate from, and set in between, and secured to, the end sections of the complete turbine casing.

Having now fully described my inven tion, what I claim and desire to protect by Letters Patent is:

1. A steam turbine comprising a case and a cover, each of said elements comprising semi-cylindrical secured-together sections, namely: a central section and end sections; semi-annular steam chests formed integral with the central sections of the case and cover respectively and abutting one against the other to form two alining halves of a wall dividing the turbine into separate wheel chambers.

2. A steam turbine comprising a case and cover and an intermediate wall dividing the turbine into an ahead chamber and an astern chamber, said wall being hollowed out to form two steam chests communicating with the respective chambers, the case and cover each comprising a semi-cylindrical section integral with said division wall and separate semi-cylindrical sections secured to opposite ends of the first section.

3. A steam turbine comprising ashaft, spaced-apart stufling boxes surrounding the shaft, and two division wall sections arranged in the same plane perpendicular to the axis, each of said sections being hollow to provide a steam chest and alsop'rovided with an integral external semi-cylindrical flange, the fiangesof said sections forming together the central part of the turbine casing, and end sections secured to opposite ends of the central sections and forming with the central sections the cylindrical casing of the turbine, there being a bleed-off connection from the chamber formed between the stufling boxes.

i. A steam turbine comprising two cylindrical casings forming compartments for the ahead and astern turbines, a centrally disposed shaft for the turbines, and a common internal head for said two compartments, to either side of which one of said casings is adapted to be bolted, there being two cored steam passages in said head on opposite sides of said shaft.

In testimony of which invention, I have hereunto set my hand, at Trenton, N. J on this 29th day of September, 1919.

CARL R. WALLER.

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