DESC:
FORM 2
THE PATENT ACT 1970
(39 of 1970) &
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10 and rule 13)
1. TITLE OF THE INVENTION
DUAL PLATE CHECK VALVE WITH DASHPOT

APPLICANT (S)
(a) Name of Applicant (s) : FLOVEL VALVES PVT LTD
(b) Nationality of Applicant(s) : INDIAN
(c) Address of Applicant(s) : 1201, GIDC,
VITTHAL UDYOGNAGAR
ANAND388121,
GUJART, INDIA

The following specification particularly describes the invention and the manner in which it is to be performed.

DUAL PLATE CHECK VALVE WITH DASHPOT

FIELD OF INVENTION
The present invention relates to a DUAL PLATE CHECK VALVE WITH DASHPOT ASSEMBLY is used in pipelines as a protection device for pumps and compressors and also for controlling the direction of flow in a piping system. DUAL PLATE CHECK VALVES WITHOUT DASHPOT ASSEMBLY is widely used in pipelines as a protection device for Pumps and Compressors. These pumps and pipelines are used in a wide range of applications like Oil and Gas Pipelines, Petrochemical Pipelines, Water Works and HVAC. These Dual Plate Check Valves are installed at the discharge side of pumps/compressors for protecting the pump/compressors.

BACKGROUND ON INVENTION
The double check valve assembly is suitable for prevention of back pressure and back siphon age, but is not suitable for high hazard applications. It is commonly used on lawn irrigation, fire sprinkler and combi-boiler systems. If the hazard is higher, even a relatively low hazard such as using antifreeze in the fire sprinkler system, then a more reliable check valve such as a reduced pres-sure zone device may be mandated.

Dual Plate Check Valves are installed at the discharge side of pumps / compressors. These pumps / compressors have to pump fluid continuously through out the plants working . Any kind of down time due to pump / compressor failure results in a huge loss to company owning the plant. When pumps are running, the role of Dual Plate Check Valve is just to allow the flow to pass through valve. Main role of Dual Plate Check Valve comes when there are changes in flow. These changes in flow will mainly occur when a pump / compressor is start or shut down the pump / compressor. Shut down of pump / compressor may be due scheduled maintenance or due to power failure. At these two conditions – Start-up or Shut-down surge conditions are created. Due to these surges flow from discharge side of pumps may try to enter into the valve. If the Check Valve installed at the discharge side of pump will not function correctly then the fluid returning back will hit the pumps / compressor and will damage the pump / compressor.

In the Patent Application no. HK1197759 , A check valve in which a stop pin assembly is situated so as to prevent the movement of a flapper beyond a predetermined position. In a preferred embodiment the check valve has two flappers with the stop pin assembly situated there between to prevent either one of them from pivoting beyond an essentially vertical position. The stop pin assembly is configured such that it can be inserted and locked in place when the check valve is inserted within a valve body that contains the check valve. The stop pin assembly can comprise three elements including a cen-tral portion and first and second end portions, although the stop pin assembly could instead comprise a single element. The stop pin as-sembly is inserted between two holders and in a preferred embodi-ment is rotatable to a locking position where it is affixed in place by fasteners.

Another patent application for “An improved dual plate check valve”. AU2015249156 (A1) A dual plate type check valve comprising a rela-tively short tubular housing 1 adapted to be mounting in a pipeline and provided with a two fluid inlets 2 each configured in the form of the capital letter D formed in an upstream end wall of the housing 1 a fluid outlet 3 in the downstream end of the housing 1, a landing or valve seat 4 formed on the downstream face of the end wall of the housing 1, an elastomeric valve member 5 mounted in sealing en-gagement with said landing or valve seat 4 and retained in place by a retaining member 6 mounted in a groove 9 in the valve member 5 and fixing screws 7 affixed to a bridge 8 formed between the fluid inlets 2, two metal reinforcing plates 0 each configured in the form of the capital letter D being encapsulated within the valve member 5 to form two reinforced sections 15 which sealingly overlay the corre-sponding fluid inlets 2 and which may flex about the retaining mem-ber 6 and such that the inner side faces 1 of the groove 9 abut said retaining member 6 during progressive inward flexing of the rein-forced sections 15 to form a fulcrum point 12 about which the rein-forced sections 15 of the valve member may pivot.

In the US5711343 for A dual plate check valve comprises a substantially cylindrical valve body 10 provided with a diametrical cross-member 14 thereby defining a pair of substantially D-shaped apertures, and two sub-stantially D-shaped plates 18, pivotally connected by a hinge means 20 parallel to said cross-member 14, and pivotable between a valve open po-sition and a valve closed position in which the sealing face of each plate engages a sealing face provided on a valve seat 16 which surrounds each aperture. A groove is provided in each sealing face which is then filled with a weld inlay 40, 42 and then machined to provide a sealing face portion of a more durable metal alloy.

The all above patents do not explain to prevent the pump /compressor with dual plate check valves. In order to prevent damage to pump / compressor Dual Plate Check Valves must be equipped with a Surge Reducing device like a Dashpot. This Dashpot will allow the valve to close quickly and prevent slamming.

To overcome such problem, The present invented DUAL PLATE CHECK VALVE WITH DASHPOT is used to overcome the situation of surge protection during start up or shut down surge conditions.

OBJECT OF THE INVENTION
The main object of the present invented DUAL PLATE CHECK VALVE WITH DASHPOT is used to prevent any damage in running pump/ compressor due to shut down surge conditions.
The further object of the present invention is also used to reduce to noise created during the surge conditions.
The present invention has been provided with DASHPOT to close the DUAL PLATE CHECK VALVE very quickly.
The present invented DUAL PLATE CHECK VALVE WITH DASHPOT can be installed in place of existing DUAL PLATE CHECK VALVE.
The maintenance cost of the present invented DUAL PLATE CHECK VALVE WITH DASHPOT is very low and which can be replaced in the case of defect creates in DASHPOT.

SUMMARY OF THE INVENTION
The present invented DUAL PLATE CHECK VALVE WITH DASHPOT are installed at the discharge side of pumps / compressors. These pumps / compressors have to pump fluid continuously throughout the day by 24X7. When any kind of down time failure accrued during running condition of pump/compressors, the present invented DUAL PLATE CHECK VALVE WITH DASHPOT will close the dual plate check valve instantly and not allow the flow to pass through valves, which will prevent a huge loss to company owning the plant. The present invented DUAL PLATE CHECK VALVE WITH DASHPOT play main role when there are changes in flow, these changes in flow will mainly occur when a pump / compressor is start or shut down the pump / compressor. Shut down of pump / compressor may be due scheduled maintenance or due to power failure. At these two conditions – Start-up or Shut-down, surge conditions are created. Due to these surges flow from discharge side of pumps may try to enter into the valve. If the Check Valve installed at the discharge side of pump will not function correctly then the fluid returning back will hit the pumps / compressor and will damage the pump / compressor. In order to prevent damage to pump / compressor Dual Plate Check Valves must be equipped with a Surge Reducing device like a Dashpot. This Dashpot will allow the valve to close quickly and prevent slamming

BRIEF DESCRIPTION OF THE DRAWING
It will be convenient to further describe the present invention with respect to the accompanying drawings that illustrate possible arrangements of the invention. Other arrangements of the invention are possible, and consequently the particularity of the accompanying drawings is not intended to be limiting of the present invention.

Fig-1 represents the dual plate check valve is provided with dashpot box on the dual plate check valve
Fig.2 represents the top view of dual plate check valve is provided with dashpot box on the dual plate check valve in close position
Fig.3 represents the top view of dual plate check valve is provided with dashpot box on the dual plate check valve in open position
Fig.4 represents the top view of dual plate check valve is provided with dashpot box on the dual plate check valve in close position with detailed view of connection between LINK-1 (8) and DRIVE SHAFT (4).
Fig.5 represents the Assembly view of SPRING CYLINDER (A3).
Fig.6 represents the Assembly view of HYDRAULIC CYLINDER (A4)

Detailed description of the invention
Before explaining the present invention in detail, it is to be understood that the invention is not limited in its application to the details of the construction and arrangement of parts illustrated in the accompanying drawings. The invention is capable of other embodiments, as depicted in different figures as described above and of being practised or carried out in a variety of ways. It is to be understood that the phraseology and terminology employed herein is for the purpose of description and not of limitation.

As shown in Fig-1, entire assembly of can be divided into Four conceptual sub assembly, wherein
1. Assembly (A1) is the valve assembly: Valve assembly (A1) consists of parts valve body (1), door or plate (2), hinge shaft or hinge pin (3), drive shaft (4), carrier (5), hex nut (6), lock pin 1 or bolt (7), link-1 (8), link-2 (9), lock pin 2 or bolt (10), hex nut (11), screw (12), coupling (13) as shown in fig-1 and fig-4.
2. Assembly (A2) is dashpot assembly:
Assembly dashpot box (A2) consists of parts dashpot box (19), guide shaft (21), yoke (22), guide block (23), slider (24), guide pin (25), stem shaft (26), key (27), yoke cover (28) as shown in fig-5 and 6.

3. Assembly (A3) is spring cylinder assembly: Assembly spring cylinder (a3) consists of spring (14), spring cylinder bottom plate or bottom cover (15), hex nut (16), spring cylinder top plate or top cover (17), spring cylinder shaft (18), tie rod (20) as shown in fig-5.

4. Assembly (A4) is hydraulic cylinder assembly: Assembly hydraulic cylinder (a4) consists of hydrauilic cylinder or dashpot or coushining cylinder (29), impact rod (30) as shown in fig-5 and fig-6.

Valve assembly (A1) is connected with dashpot assembly (A2). spring cylinder assembly (A3) and hydraulic cylinder assembly (A4) are connected to valve assembly (A1). fig-2 shows valve in completely close position. fig-3 shows valve in completely open position. fig-4 shows detailed view of connection between link-1 (8) and drive shaft (4). Both these parts are coupled using coupling (13). fig-5 shows inside view of dashpot assembly when valve assembly (A1) is in close position. fig-6 shows inside view of dashpot assembly with valve assembly (A1) is in open position.

As shown in fig.1, dual plate check valve is provided with dashpot box on the dual plate check valve. The valve body (1) is a cast body or maybe fabricated using plates, two d-shaped seat of the valve body is closed by two doors (2). Hinge pin (3) are provided in the hinges of doors to allow opening and closing of dual plate check valve doors(2). Stop pin (4) is also provided on the both side of the dual plate check valve doors(2) to prevent doors from opening more than the required angle. The retainer flats plates (5) are provided to retain entire assembly in the valve body. The hex nuts (6) are provided to close link pin (7), which will open or close the doors through the link (8, 9) at both sides. The present invented dual plate check valve with dashpot is installed at the discharge side of pumps / compressors. These pumps / compressors have to pump fluid 24x7. when any kind of down time failure accrued during running condition of pump/compressors, the present invented dual plate check valves with dashpot will close the dual plate check valves instantly which is not allow the flow to pass through valves, which will prevent a huge loss to company owning the plant.
During failure condition of the pump/ compressor, doors are required to close instantly and prevent huge surge conditions. to overcome such limitation in the present invention dashpot box (10) is installed on dual plate check valve, which will close the dual plate check valves doors (2) instantly and also prevent to create huge slamming. the more than 80% of travel doors will close instantly and remaining 20%, door will close slowly, which also reduce notice creates in doors closing operation. The dashpot box (10) is provided with hydraulic (11) and springs (12) provided on it to maintain the pressure created on doors (2).
The present invented dual plate check valve with dashpot is used to prevent any damage in running pump/ compressor due to surge conditions and also used to reduce to noise created during the surge conditions. The present invention has provided with dashpot to close the dual plate check valve very quickly to prevent the fluid linkage in pipeline which will prevent the pumps or compressor. The maintenance cost of the present invented dashpot is very low and which can be replaced in the case of defect creates in dashpot.

While, the invention has been described with respect to the given modifications and other applications of the invention may be made. however, it is to be expressly understood that such modifications and adaptations are within the scope of the present invention, as set forth in the following claims.

,CLAIMS:We claim
1. DUAL PLATE CHECK VALVE WITH DASHPOT assembly is divided into valve assembly , dashpot assembly, spring cylinder assembly, hydraulic cylinder assembly
wherein valve assembly (A1) consists of parts valve body (1), door or plate (2), hinge shaft or hinge pin (3), drive shaft (4), carrier (5), hex nut (6), lock pin 1 or bolt (7), link-1 (8), link-2 (9), lock pin 2 or bolt (10), hex nut (11), screw (12), coupling (13);
wherein dashpot assembly (A2) consists of dashpot box (19), guide shaft (21), yoke (22), guide block (23), slider (24), guide pin (25), stem shaft (26), key (27), yoke cover (28) ;
wherein spring cylinder assembly (A3) consists of spring (14), spring cylinder bottom plate or bottom cover (15), hex nut (16), spring cylinder top plate or top cover (17), spring cylinder shaft (18), tie rod (20);
wherein hydraulic cylinder assembly (A4) consists of hydraulic cylinder or dashpot or cushioning cylinder (29), impact rod (30).

2. DUAL PLATE CHECK VALVE WITH DASHPOT as claimed in claim 1 wherein hinge pin (3) are provided in the hinges of D-shape doors to allow opening and closing of dual plate check.
3. DUAL PLATE CHECK VALVE WITH DASHPOT as claimed in claim 1 wherein stop pin (4) is also provided on the both side of the dual plate check valve doors(2) to prevent doors from opening more than the required angle limit upto 800.
4. DUAL PLATE CHECK VALVE WITH DASHPOT as claimed in claim 1 wherein the retainer flats plates (5) are provided to retain entire assembly in the valve body.
5. DUAL PLATE CHECK VALVE WITH DASHPOT as claimed in claim 1 wherein the hex nuts (6) are provided to close link pin (7), which will open or close the doors through the link (8, 9) at both sides.
6. DUAL PLATE CHECK VALVE WITH DASHPOT as claimed in claim 1 wherein dashpot is installed at the discharge side of pumps / compressors.
7. DUAL PLATE CHECK VALVE WITH DASHPOT as claimed in claim 1 wherein the dashpot box (10) is provided with hydraulic (11) and springs (12) provided on it to maintain the pressure created on doors (2).
8. DUAL PLATE CHECK VALVE WITH DASHPOT as claimed in claim 1 wherein dashpot box (10) is installed on dual plate check valve, which will close more than 80% of travel doors instantly and remaining 20%, door will close slowly, which also reduce notice creates in doors closing operation.

Dated this 11th July 2016
For,
FLOVEL VALVES PVT LTD

To, Mr. Baiju Thakar
The Controller of Patents,
The Patent Office, at MUMBAI.