WO2015186085A1

WO2015186085A1 - A rotary union steam trap

Info

Publication number: WO2015186085A1
Application number: PCT/IB2015/054223
Authority: WO
Inventors: Datta KUVALEKAR; Sachin BONDAVE; Pranil CHAVAN – PATIL
Original assignee: Forbes Marshall Private Ltd.
Priority date: 2014-06-05
Filing date: 2015-06-04
Publication date: 2015-12-10
Also published as: GB2541331A; GB201620398D0; GB2541331B

Abstract

A rotary union steam trap comprises a housing, an inlet, a rotating pipe, a stationary pipe, at least one orifice, a control mechanism and an outlet. The housing comprises a steam compartment that receives steam from the inlet, a steam condensate compartment and a condensate compartment. The rotating pipe fitted to the steam compartment supplies steam to a rotating appliance in need of steam. The stationary pipe opens at one end in the rotating appliance and the other end in the steam condensate compartment and leads steam condensate mixture from the rotating appliance to the steam condensate compartment. The orifice formed between the steam condensate compartment and the condensate compartment leads condensate from the steam condensate compartment to the condensate compartment by a control mechanism fitted in the steam condensate compartment. The outlet with a non return valve leads condensate from the condensate compartment to the environment outside the trap.

Description

A ROTARY UNION STEAM TRAP

FIELD

The present disclosure relates to the field of mechanical engineering. In particular, the present disclosure relates to the field of steam traps.

BACKGROUND

Steam traps are automatic valves that release condensed steam [condensate] from a steam space while preventing the loss of live steam. If not discharged, the condensate reduces the system efficiency and causes corrosion and water hammering. Rotating unions or rotary joints are employed in various industrial applications such as paper dryers, textile dryers, corrugated dryers, high speed drilling and boring transfer operations, high speed machine tool spindles, and in other operations where it is necessary to transfer a fluid medium to a rotating device.

Some of the problems observed with the conventional systems employed in the process of steam trapping include high manufacturing and installation costs, lower condensate removal, high weight and size of the system, high leakage probability, large number of piping and fitting, difficulty in installation, and longer time periods required for assembly.

Hence, there is need for a steam trap which will overcome the drawbacks of the conventional steam trap.

OBJECTS

Some of the objects of the system of the present disclosure, which at least one embodiment herein satisfies, are as follows:

It is an object of the present disclosure to ameliorate one or more problems of the prior art to at least provide a useful alternative.

Another object of the present disclosure is to provide a rotary union steam trap which is efficient in separating condensate from steam and removing the condensate from the rotary union steam trap hence comparatively reduces water hammering there-within caused due to the condensate.

Yet another object of the present disclosure is to provide a rotary union steam trap which discharges higher amount of condensate compared to the conventional steam traps.

Still another object of the present disclosure is to provide a rotary union steam trap which is relatively easy and quick to install.

An additional object of the present disclosure is to provide a rotary union steam trap which is comparatively lighter in weight.

Another object of the present disclosure is to provide a rotary union steam trap which has relatively lower maintenance requirements, and hence, lower maintenance costs associated therewith, as compared to conventional steam traps.

Other objects and advantages of the present disclosure will be more apparent from the following description when read in conjunction with the accompanying figures, which are not intended to limit the scope of the present disclosure.

SUMMARY

The present disclosure envisages a rotary union steam trap. A rotary union steam trap comprises a housing, an inlet, a rotating pipe, a stationary pipe, at least one orifice, a control mechanism and an outlet. The housing comprises a steam compartment, a steam condensate compartment and a condensate compartment. The inlet provides steam to the steam compartment. The rotating pipe is fitted to the steam compartment for supplying steam to a rotating appliance in need of steam. The stationary pipe opens at one end in the rotating appliance and the other end in the steam condensate compartment for leading steam condensate mixture from the rotating appliance to the steam condensate compartment. The stationary pipe is passing through a bore of the rotating pipe, the arrangement is such that steam is lead to the rotating appliance from the steam chamber via an annular space formed between the rotating pipe and the stationary pipe. The orifice is formed between the steam condensate compartment and the condensate compartment to lead condensate from the steam condensate compartment to the condensate compartment. The control mechanism is fitted in the steam condensate compartment to permit only condensate from the steam condensate compartment to be lead through the condensate compartment. The outlet with a non return valve for leading condensate from the condensate compartment to the environment outside the steam trap.

BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS

A rotary union steam trap of the present disclosure will now be described with the help of accompanying drawings, in which:

Figure 1 illustrates a cross sectional view of a rotary union steam trap, in accordance with an embodiment of the present disclosure;

Figure 2 illustrates an isometric view of the rotary union steam trap of Figure 1;

Figure 3 illustrates a cross sectional view of a locking arrangement connecting a stationary pipe and a portion of a steam compartment of the rotary union steam trap of Figure 1;

Figure 4a illustrates a cross sectional view of a control mechanism of the rotary union steam trap of Figure 1, wherein the control mechanism is at a first position;

Figure 4b illustrates a cross sectional view of the control mechanism of Figure 1, wherein the control mechanism is shown in first position as well as in second positon; and

Figure 5 illustrates a cross sectional view of a strainer disposed in the rotary union steam trap of Figure 1.

DETAILED DESCRIPTION

A preferred embodiment of a rotary union steam trap of the present disclosure will now be described in detail with reference to the accompanying drawings. The preferred embodiments do not limit the scope and ambit of the disclosure. The description provided is purely by way of example and illustration.

The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.

The following description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

The present disclosure envisages a rotary union steam trap that transmits steam from a steam source to a rotating application. The rotary union steam trap separates the condensate from the steam formed within the rotating application more efficiently and further removes the condensate disposed there-within thereby comparatively reducing water hammering in the rotary union steam trap casued the condensate.

Referring to Figure 1, Figure 2 and Figure 5, a rotary union steam trap, in accordance with the present disclosure is generally indicated with the reference number 100. The rotary union steam trap 100 comprises a steam compartment 10, a stationary pipe 20, a rotating pipe 30, a steam condensate compartment 40, a condensate compartment 50, a control mechanism 60 and a non return valve 70.

The steam compartment 10 receives steam 'S' (i.e. the live steam) from a steam source (not illustrated in Figures) through an inlet 10a. The rotating pipe 30 is rotatably disposed in the steam compartment 10. The stationary pipe 20 is fitted in a bore 30a of the rotating pipe 30. The stationary pipe 20 is prevented from rotation by a locking arrangement. Typically as illustrated in Figure 3, the locking element comprises at least one flange 25 securely connected to a portion 10b of the steam compartment 10 and bolts 26. An annular space 30b is formed between the stationary pipe 20 and rotating pipe 30. The steam 'S' from the steam compartment 10 is lead to a rotating appliance 35a which is connected to the rotating pipe 30 which utilizes steam 'S' to perform certain activity. The stationary pipe has one end 20b that opens in the rotating appliance 35a and other end 20c connected to the steam condensate compartment 40.

Typically, the rotating applicance 35a may be a textile drier, a paper drier, a refinery drier and other like driers. In an examplary embodiment, the rotating applicance 35a has an outer chamber 35b and an inner chamber 35c in which articles to be dried are disposed. The steam 'S' is adapted to flow in the rotating applicance 35a. Due to heat transfer, a portion of the steam 'S' gradually condenses and hence forms a steam condensate mixture 'CM' of steam and condensate. The steam condensate mixture 'CM' then passes to the steam condensate compartment 40 through a bore 20a of the stationary pipe 20. In one embodiment, the stationary pipe 20 is a siphon and the condensate mixture 'CM' flows because of the pressure difference between the steam condensate compartment 40 and the rotating applicance 35a.

In the steam condensate compartment 40, the condensate 'C of the steam condensate mixture 'CM' gets accumulated. As soon as the accumulated condensate 'C in the steam condensate compartment 40 exceeds a predetermined parameter, such as predetermined level or predetermined pressure or the like, the condensate 'C actuates the control mechanism 60 and allows flow of the condensate 'C from the steam condensate compartment 40 to the condensate compartment 50 through at least one orifice 40a configured on the steam condensate compartment 40. In accordance with one embodiment of the present disclosure as illustrated in Figure 4a and Figure 4b, the control mechanism 60 comprises a lever 60a and a float 60b. In one embodiment, the lever 60a is connected to at least one orifice closure 60c. The float 60b is connected to the orifice closure 60c at a first joint 62 through the lever 60a. The float 60b is displaced to a second position 60bi from its first position 60bii (as illustrated in Figure 4b) due to the buoyant force exerted by the condensate 'C when the condensate 'C in the steam condensate compartment 40 exceeds the predetermined parameter. The displacement of the float 60b to the position 60bi displaces the lever 60a and thereby displaces the orifice closure 60c to open the orifice 40a for allowing flow of the condensate 'C from the steam condensate compartment 40 to the condensate compartment 50.

In case when the condensate 'C in the steam condensate compartment 40 is below the predetermined parameter, the float 60b regains its first position 60bii and hence the lever 60a displaces in such a way that the orifice closure 60c closes the orifice 40a and hence prevents flow of the steam 'S' disposed in the steam condensate compartment 40 to the condensate compartment 50 thereby facilitating trapping of the steam 'S'. The control mechanism 60 thus controls the flow of the condensate 'C from the steam condensate compartment 40 to the condensate compartment 50.

In accordance with one embodiment of the present disclosure, a stopper (not illustrated in Figures) is provided that restricts the displacement of the float 60b beyond a pre-defined limit.

In one embodiment, a level sensor (not illustrated in Figures) is used which sends signal to the control mechanism to open and close the orifice 40a for controlling the flow of condensate 'C from the steam condensate compartment 40 to the condensate compartment 50.

Althought, the control mechanism 60 of the present disclosure is described by the lever 60a and float 60b mechanism. However, the control mechanism 60 of the present disclosure is not limited to the use of the lever 60a and float 60b mechanism, any other mechanisms that can control the flow of the condensate 'C from the steam condensate compartment 40 to the condensate compartment 50 may be used. Some of the non-limiting examples are thermodynamic control mechanisms, thermostatic control mechanisms or other controlling mechanical mechanisms may be used.

The condensate 'C accumulated in the condensate compartment 50 is lead outside the rotary union steam trap 100 through an outlet 50a configured on the condensate compartment 50.

In accordance with one embodiment of the present disclosure, the non return valve 70 is fitted in the condensate compartment 50 to allow one way flow (unidirectional flow) of the condensate 'C to the outlet 50a.

In accordance with one embodiment of the present disclosure, the rotary union steam trap 100 further comprises at least one seal disposed on the rotating pipe 30 and within the steam compartment 10 to prevent leakage of the steam 'S' from the steam compartment 10. In an exemplary embodiment three seals 80a, 80b and 80c are fitted on the rotating pipe 30. The seals 80a, 80b and 80c enables providing damping action and bearing action. The seal 80c acts as a support element and a primary guide to the rotating pipe 30. The seal 80b has a profile complementary to a profile (typically, conical profile) configured on a portion of the rotating pipe 30 for enabling secure holding of the seal 80b. In one embodiment, a spring 85 is fitted in the steam compartment 10 in such a way that the spring 85 exerts pressure on the seals 80a, 80b and 80c to prevent leakage of the steam 'S' from the steam compartment 10 and to facilitate damping.

In accordance with one embodiment, a drain 88 is configured on the steam condensate compartment 40 to facilitate removal of foreign particles accumulated in the steam condensate compartment 40 along with the condensate 'C

In accordance with one embodiment as illustrated in Figure 5, the rotary union steam trap 100 further comprises at least one strainer 90. The strainer 90 receives the steam condensate mixture 'CM' from the stationary pipe 20 and strains foreign particles from the steam condensate mixture 'CM' and passes the strained steam condensate mixture 'CM' to the steam condensate compartment 40 thereby preventing entry of foreign particles in the steam condensate compartment 40. In one embodiment, each of the strainer 90 is provided with a plug 90a for removal of the foreign particles from the rotary union steam trap 100.

The removal of foreign particles through the plug 90a of the strainer 90 or the drain 88 relatively reduces damage to the rotary union steam trap 100. Hence, the rotary union steam trap 100 requires relatively lower maintenance requirements, and hence, lower maintenance costs associated therewith, as compared to conventional steam traps

In one embodiment, an air vent 92 is provided in the rotary union steam trap 100 to release air trapped in the steam condensate compartment 40 and a steam lock release 94 to release steam locked in the steam condensate compartment.

In one embodiment, a vacuum breaker 96 is removaly connected on the steam compartment 10 to prevent vacuum formation in the rotating applicance 35a. The vaccum breaker when removed, enables atmospheric air to flow into the rotating applicance 35a and hence prevent vacuum formation there -within.

The rotary union steam trap 100 requires relatively less numer of piping requirements and hence is comparatively light in weight. Also, owing to comparatively lesser elements, the rotary union steam trap 100 is relatively easy and quick to install.

TECHNICAL ADVANCEMENTS

The present disclosure has several technical advantages including, but not limited to, the realization of a rotary union steam trap that:

- is efficient in separating condensate from steam and removing the condensate from the rotary union steam trap hence comparatively reduces water hammering there- within caused due to the condensate;

- discharges high amount of condensate;

- is easy and quick to install;

- requires comparatively less piping requirement and hence is comparatively lighter in weight; and

- has lower maintenance requirements and hence lower maintenance costs. Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.

The use of the expression "at least" or "at least one" suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.

The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

Claims

CLAIMS:

1) A rotary union steam trap comprising:

• a housing comprising a steam compartment, a steam condensate compartment and a condensate compartment;

• an inlet for providing steam to said steam compartment;

• a rotating pipe fitted to said steam compartment for supplying steam to a rotating appliance in need of said steam;

• a stationary pipe opening at one end in said rotating appliance and the other end in said steam condensate compartment for leading steam condensate mixture from said rotating appliance to said steam condensate compartment, said stationary pipe passing through a bore of said rotating pipe, the arrangement being such that steam is lead to said rotating appliance from said steam chamber via an annular space formed between said rotating pipe and said stationary pipe;

• at least one orifice formed between said steam condensate compartment and said condensate compartment to lead condensate from said steam condensate compartment to said condensate compartment;

• a control mechanism fitted in said steam condensate compartment to permit only condensate from said steam condensate compartment to be led through said condensate compartment; and

• an outlet with a non return valve for leading condensate from said condensate compartment to the environment outside the steam trap.

2) The rotary union steam trap as claimed in claim 1, wherein said control mechanism comprises:

• a lever; and

• a float connected to said lever to configure said lever between a first position in which said lever closes said at least one orifice and a second position in which the lever is displaced to open said at least one orifice for passage of said condensate there-through under displacement of said float by accumulation of a predetermined quantity of condensate in said steam condensate compartment. 3) The rotary union steam trap as claimed in claim 2, further comprising a stopper adapted to restrict displacement of said float beyond a pre-defined limit.

4) The rotary union steam trap as claimed in claim 1, further comprising a plurality of seals are provided to permit rotation of said rotating pipe within said steam trap.

5) The rotary union steam trap as claimed in claim 4, further comprising a spring damping means to exert pressure on said seal to prevent leakage of said steam from said steam compartment.

6) The rotary union steam trap as claimed in claim 1, wherein said stationary pipe is prevented from rotation by a locking arrangement.

7) The rotary union steam trap as claimed in claim 1 , further comprising at least one strainer adapted to receive said steam condensate mixture from said stationary pipe and further adapted to prevent entry of foreign particles in said steam condensate compartment, said strainer is provided with a plug for removal of said foreign particles.

8) The rotary union steam trap as claimed in claim 1 , further comprising a drain configured on said steam condensate compartment to facilitate removal of foreign particles accumulated in said steam condensate compartment along with said condensate.

9) The rotary union steam trap as claimed in claim 1, comprising an air vent adapted to release air trapped in said steam condensate compartment and a steam lock release for removing steam locked in said steam condensate compartment.

10) The rotary union steam trap as claimed in claim 1, comprising a vacuum breaker removably disposed on said steam compartment to prevent vacuum formation in said rotating applicance.