US1749406A - Valve-controlling apparatus - Google Patents

Description

March 4, 1930. o WQODSQME 1,749,406

VALVE CONTROLLING APPARATUS Original Filed June 16. 1926 Patented Mar. 4, 1930 PATENT OFFICE JOHN 0. WQODSOME, OF DETROIT, MICHIGAN VALVE-GONTROLLING APPARATUS Original application vfiled June 16, 1926, Serial No. 116,306. Divided and this application filed December 1-2, 1927; Serial No. 239,504.

This invention relates to valve controlling apparatus for steam drying systems such as paper machine driers and the like.

As pointed out in my copending application entitled, Valve controlling apparatus, Serial No. 116,306, filed June 16, 1926, of which thepresent application is a division, for the economical operation of steam drying systems, it is important where possible to.

use low pressure steam and to maintain as low a back pressure on the system as is consistent with obtaining the desired temperature in the driers and with obtaining an efficient transfer of heat from the steam to the drying cylinders. In order to utilize the sometimes limited and varying available supplies of the exhaust steam from primary movers, such assteam engines, pumps and turbines, in the drying system, various types of control apparatus have been devised for supplementing such low pressure steam with live steam. The economy of the system depends upon the 'efliciency of such control apparatus.

It is therefore an object of this invention to provide a valve controlling apparatus for dryingsystems, using both low and high pressure steam that will automatically regulate the flow of live steam to the driers, whereby a uniform pressure may be maintined in the driers without the use of unnecessary quantities ofllive steam.

It is-a furtherobject of this invention to provide a steam drying system wherein automatically operated diaphragm controlled valves are utilized for controlling the fiowof low pressure and high pressure steam to the driers in accordance with the pressure requirements" of said driers to maintain the jhighest dry efficiencies consistent with economical-use of the steam.

- Other andfurthger important objects of this invention will be apparent from the disclo sures in the specification and the accompanying a i s,-

5 1n the accompanying drawings which i1- lustrate a preferred embodiment of this invention and in which similar reference numerals refer to similar features in the different views:

Figure 1 is a fragmentary elevational view of a valve controlling apparatus embodying the principles of my invention, as applied to a drying system for paper machines, with parts of the valves broken away and in sec tion to show their construction.

Figure 2 is an enlarged sectional view of one of the valves.

As shown on the drawings:

The reference numeral 1 indicates a drier header for distributing steam to the various driers of a paper machine, or other steam using apparatus of similar type. An exhaust steam line 2 is connected directly to the drier header 1 without any intermediate valves, and a live steam line 3 is connected to said header 1 through a diaphragm controlled valve 4. A

similar valve 5 in the piping 6 connects the exhaust steam line 2 with an exhaust relief line 7.

Valve 4, as better shown in Figure 2, comprises a globular body portion 8 having flanged ends 9 and an inner double portedvalve seat wall 10. Said valve seat wall 10 is integrally formed with the body portion 8 and is provided with aligned upper and lower ports 11 having beveled valve seats 12. The top face of said body portion 8 is flattened, as at 13,and a valve operating device 14 is bolted or otherwise secured thereto. Said device 14 comprises upper and lower stufling boxes 15 and 16,'spaced apart byarms 17. A valve stem 18 is adapted to pass through said stuffing boxes 15 and 16 and through packing glands 19 and 20 threaded therein. Said valve stem 18 carries a pair of spaced valves 21 adapted to seat in the valve seats 12. The upper stuffing box 15 is provided with a recessed and flanged upper face 22 adapted to form with a similarly recessed and flanged cap .23, a chamber 241 A flexible diaphragm or disc secured to the upper end of said valve stem 18, is adapted to be clampingly held at its periphery between said flanged face 22 and the flanged cap 23. Threaded passages 26 and 27 are provided in the face 22 and the cap 23, respectively, communicating with the chamber 24: on opposite sides of the diaphragm 25. Piping 28 and 29 connect with said passages 26 and 27 respectively, the piping 28 leading to a pipe 30 for conducting some fluid such as air under measured pressure, and the piping 29 connecting with the drier header 1. ver arm 31 is pivoted at one end to an arm 17 and is secured intermediate its ends to the valve stem 18. The free end of said lever 31 carries a slidably mounted weight 32 for adjusting the pressure of the Valves 21 against their valve seats 12.

Valve 5 is similar in construction to valve 4, but since its valves 33 are intended to be closed the greater part of the time, the weighted lever arm 34 is pivoted at one end to the valve stem 35 and intermediate its ends to an arm 36. Piping 37 and 38 lead from the upper and lower halves of the diaphragm chamber 39 to the drier header 1 and to the pipe 30, respectively, Said pipe 30 is provided with a pressure gauge 40 and a valve 41 for regulating the pressure of the air or other fluid to the pressure desired to be maintained in the drier header. v

The operation of the valve controlling apparatus is substantially as follows:

Whenever the pressure in the drier header 1 falls below that desired as shown onthe gauge 40, the differential pressure in the diaphragm chamber 24 operates to open the valve 4: to admit live steam. Otherwise exhaust steam only is used as supplied through the pipe 2 from any primary engine. By exhaust steam is meant to include low pressure steam obtained from any source suitable for the purpose. When the pressure of the exhaust steam is greater than that desired in the drier header, valve 5 is opened by automatic operation of the diaphragm mechanism in chamber 39 to vent the excess exhaust steam through pipe 7.

It will be evident, therefore, that when the desired pressure in the drier header can be maintained by the use of lowpressure steam alone, no live or high pressure steam will be admitted, but that when the pressure in the drier header falls below the required amount, the low pressure steam will be supplemented by live steam in just sufficient quantity to maintain the desired pressure in the drier header. The resulting saving from such automatic control of the steam is apparent.

I am aware that numerous details of construction may be varied through a wide range without departing from the principles of this invention, and I therefore do not purpose A le-' limiting the patent granted hereon, otherwise than necessitated by the prior art.

I claim as my invention:

1. In a steam drying system for paper ma chines, a drier header, a low pressure steam supply line and a live steam supply line for said header, an exhaust line, diaphragm regulated valves between said live steam line and said low pressure line and between said low pressure llne and said exhaust line, a

source of fluid under measured pressure con nected to the same side of each of said dia phragms, and means connecting the other sides of said diaphragms to said header, whereby whenthe pressure in said header falls below the pressure of the fluid, live steam will be admitted to the header and when the pressureof the lowpr'essure steam sure of said low pressuresteam falls below the pressure of said fluid and to exhaust said low pressure steam when the pressure in said drier header goes above a predetermined value. 3 a

3. In a steam drying system, a steam distributing header, low pressure and high pressure steam lines connected thereto, a single fluid line for conducting fluid under regulated pressure, valves connected between said fluid pressure line and said header and controlled by said fluid pressure for automatically controlling admission of high pressure steam to maintain a pressure in said header the same as said fluid pressure, and other valves of the same nature also connected between said fluid pressure line and said header and responsive to the pressures therein for automatically exhausting the low pressure steam when the pressure of the low pressure steam exceeds that of the fluid.

4. A steam drier system including a' drier header, a low pressure steam supply line and a high pressure steam supply line connected to said header, and an exhaust line communicating with said low pressure supply line, a

diaphragm controlled valve between said header and said high pressure supply line, a diaphragm controlled valve between said loW pressure supply line and said exhaust, an 'air supply line connected tofthe same side of I sure the vavebaween the high pressureline and the header will be opened by the air pressure to admit live steam to said header, and when the pressure in said header exceeds the air pressure said excess pressure Will open the valve between the low pressure line and the exhaust against said air pressure to exhaust steam from said header, and means for adjusting the engagement of the valves against the valve pressure to vary the responsiveness of said valves to the unbalanced pressure conditions against the diaphragms.

In testimony whereof I have hereunto subscribed my name at Detroit, WVayne County,

Michigan.

JOHN O. WVOODSOME.

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