Cast SteelGate, Globe and Check Valves

 
AIL Cast Steel Gate, Globe and Check Valves have established themselves the world over for their quality, reliability and long service. The valves are manufactured to the latest international designs, using advanced manufacturing techniques and stringent quality control checks. The valves are regularly supplied to major Indian and international clients including oil refining companies and EPC contractors. A wide network of distributors ensures the availability of AIL valves anywhere in the world.
 
   

AUDCO INDIA LIMITED (AIL) is a leading valve manufacturer, with a strong presence in India and overseas
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AIL has three manufacturing facilities located in Southern India. The main plant is located in Manapakkam, Chennai. The two other plants are at Maraimalai Nagar, 40 kilometres south and at Kancheepuram, 70 kilometres west of the main plant. The plants are equipped with modern manufacturing facilities with special-purpose machines, automatic welding equipment, heat treatment furnaces and testing equipment for total control of all manufacturing operations. In-house metallurgical and NDE laboratories, and calibration facilities with modern equipment provide support to ensure the quality of products manufactured.

AIL manufactures a wide variety of industrial valves. The Quality Management System in all three plants is certified to ISO 9001:2000 System.

 
Quality Policy
 
Maintaining a high standard of quality consistent with the customer requirements
   
Complying with the Codes, Standards, Customer Specifications, Statutory and Regulatory requirements as applicable to our Products
   
Continually improving the effectiveness of Quality Management System to add value to our Products
 
 
 
 
 
 
 
Test Pressures for standard Carbon Steel Valves
 
Every individual valve manufactured at AIL is inspected and pressure-tested to API 598 / BS 6755 Part I requirements, for which test certificates are provided.
 
 
Low Pressure Test for Swing Check Vlaves
 
In addition to the high pressure closure test, Swing Check Valves are subjected to low pressure hydrostatic closure test at a pressure of 25% of the high pressure closure test. The duration of the test is the same as that of the high pressure closure test.
 
 
 
 
 
 
AIL has the distinction of having obtained a number of national and international approvals. Notable among these are :
 
 
ISO 9001:2000 certified Quality Management System
     
 
Certified to use "CE" marking for supply to the European Union
     
 
Specific company approvals from national and international oil majors and EPC contractors
     
 
Indian Boiler Regulation (IBR) certification for all three plants.
     
   
The valves also comply with applicable BS specifications. * Shell wall thickness as per API 600
** For valves larger than 24" (600mm), the flange drilling shall be
as per ASME B16.47 Series A (MSS SP 44) or Series B (API 605). RTJ flanges are offered as optional for Class 600 and above.
 
 

Body / Bonnet Materials

 
AIL Cast Steel Gate, Globe and Check Valves are offered in a variety of body and bonnet materials to suit different requirements. These materials include Carbon Steel (standard), Alloy Steels and Stainless Steels. For other materials of construction, refer to AIL.
 
 
 
AIL Gate, Globe & Check Valves
Bolted Bonnet / Cover design
 
The API 600 / BS 1873 / BS 1868 family of AIL Gate, Globe and Swing Check Valves is exceptionally sturdy, rugged and durable, with a reputation for quality, integrity and long service. They are designed for tight sealing and ease of operation. The valves are available with flanged ends or butt-weld ends, in pressure ratings from ASME Class 150 to Class 1500, and in a variety of materials of construction.

Gate Valves are of flexible wedge, outside screw-and-yoke and bolted-bonnet construction. The valves conform to API 600.

Globe Valves feature a ball-type disc, outside screw-and-yoke and bolted-bonnet construction. They conform to BS 1873 and also meet the general requirements of API 600, including shell wall thickness and stuffing box dimensions.

Check Valves are of swing-type and bolted-cover construction. They conform to BS 1868 and also meet the general requirements of API 600, including shell wall thickness.
 
   
Body-Bonnet Joint    
     
The body-bonnet joint for Class 150 gate valves is oval in shape, while for Class 300 and for globe valves, this joint is circular in shape. In 2" (50mm) valves, the body-bonnet joint has a square configuration.
 
   
Gate valves of Class 150 rating have a flat-face joint with a graphite gasket having metallic inserts. Those of Class 300 rating have a male-female type joint with a spirally-wound gasket. Gate valves of Class 600 rating and above have a Ring Type Joint (RTJ).
 
   
Globe and Check valves in Class 150 and 300 ratings have a male-female type joint with a spirally-wound gasket. Those of Class 600 rating and above have an RTJ.
 
     
Back Seat
In AIL gate and globe valves, a precision-machined back-seat bush is threaded in the bonnet and is secured by a tab-weld.
 
Flexible Wedge
AIL gate valves feature a one-piece cast flexible wedge that minimises stress concentration. Wedge flexibility ensures tight seating over a wide range of differential pressures and temperatures. It also adjusts to slight misalignments caused by pipeline deflections and thermal deformation. The stem-to-wedge thrust is applied close to the wedge centre. This reduces lateral stem loading and provides for more accurate wedge movement.
 
     
Yoke Sleeve and Yoke Bush    
     
Cast in austenitic, copper-free ductile iron alloy to provide resistance to heat, corrosion and wear, the Yoke Sleeve in gate valves features a long thread engagement that assures accurate alignment of the stem. Moreover, it can be removed without replacing the bonnet. In gate valves of sizes 150mm and higher in Class 600 rating and above, the yoke sleeve is mounted on thrust bearings to facilitate easy operation.
 
   
The Yoke Bush of globe valves is also made from ductile iron alloy, and has a long thread engagement for accurate stem alignment. In Class 900 and 1500 ratings, the valves have a yoke sleeve to facilitate smooth operation.
 
 
Stuffing Box
 
The machined stuffing box chamber with a flat bottom allows correct sealing of the gland packing. Surface finish is controlled to required limits, to ensure low-emission performance. Stuffing boxes are provided with five numbers of gland packing to achieve correct compression of all packings and to ensure tight sealing.

Valves in Class 300 rating and above feature a provision for a lantern ring arrangement for conditions that demand that there be no leakage of service fluid to the atmosphere. The lantern ring has a leakoff plug which allows connection for liquid or grease seal. See page 30 for more details on the lantern ring.
 
Flange Drilling and Facing finish

The standard range of AIL flanged valves in sizes of up to 24" (600mm) is finished with end-flanges faced, drilled and spot-faced (or backfaced) to ASME B16.5 Raised Face (RF). Flanges in valves of sizes larger than 24" (600mm) are drilled as per ASME B16.47 Series A (MSS SP 44) or Series B (API 605). Valves in ASME Class 600 and above are offered with RTJ end flanges on request.
The standard finish offered on the raised faces is 125¬250 microns in Ra (AARH) Spiral Serration. Other finishes can be offered on request.
 
Body and Bonnet

The body and bonnet are cast with uniform section and generous radius fillets to prevent stress concentration. The castings are precision-machined for high performance.
 
   
The gate valve body has a straight through port without  
recesses except at the seat area. This ensures minimum turbulence, erosion and resistance to flow. Long integral guide ribs in the body match with guide slots in the wedge for accurate alignment and guidance. Bonnet castings are of one-piece design, where the yoke is integral with the bonnet for gate valves of sizes up to 12" (300mm). This ensures accurate alignment of stem and a smooth operation.
 
   
In globe valves of larger sizes and for higher pressure classes of ASME Class 900 and above, the internal part of the body is machined to provide continuous
 
guiding of the disc from the open to the closed position.
 
 
The check valve body provides a full port without pockets from inlet to the valve seat. On the downstream side, the body has generous proportions to facilitate full swing of the disc to reduce disc erosion and flow resistance
 
Ball-type Disc
AIL globe valves feature a ball-type disc that provides a fine grain surface on the taper seat. For severe services that demand hard-faced seats, a plug-type disc is provided.
 
     
Swing-type Disc Assembly
The one-piece construction is securely fastened to the hinge by means of a lock nut and pin. The disc is free to rotate to avoid localized wear. The hinge pin offers excellent wear resistance properties.
Yoke Sleeve and Yoke Bush
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Seat Ring

AIL gate valves and check valves feature a seal-welded seat ring that offers a leakproof design as it eliminates the leakage path between the seat ring and the body. This design is superior to threaded seats which can loosen up due to temperature fluctuations, corrosion or vibration and result in leakage. Threaded seat rings are optional. For 50mm gate valves, the seat ring is flared into the body, while seal welding is optional.
AIL globe valves feature a shoulder type, threaded body seat ring which has a wide taper area that provides for ample seating. Slots on the seat ring allow easy in-situ removal for servicing. Threaded seat rings are additionally secured by a tab-weld. Welded seat rings are also availble in AIL Globe Valves.
 
Stem

AIL gate and globe valves feature a stem of one-piece construction, ACME threaded and precision-machined with polished surfaces to reduce friction, minimise leakage and extend stem life.
In gate valves, the heavy forged T-head engages with the T-slot in the wedge. The stem also has an integral self-adjusting radial back-seat shoulder that matches with the back-seat bush in the bonnet.
In globe valves, the stem is held to the disc by a stem nut that permits the disc to swivel. This free-floating design ensures uniform seating.
Stuffing Box
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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API 603 AIL Stainless Steel Gate Valves
 
Bolted Bonnet design    
     
The API 603 family of AIL Stainless Steel Gate Valves is an economic alternative to API 600 Stainless Steel Gate Valves. They are available in flanged construction and in pressure ratings of ASME Class 150 and Class 300.

Gate Valves are of flexible wedge,outside screw-and-yoke and bolted-bonnet construction.

 
   
Body and Bonnet

The body and bonnet are cast with uniform section and generous radius fillets to prevent stress concentration. The castings are precision-machined for high performance.
 
   
The gate valve body has a straight through port without recesses except at the seat area. This ensures minimum turbulence, erosion and resistance to flow. Long integral guide ribs in the body match with full-length guide slots in the wedge fo accurate alignment and guidance.
 

 
Flexible Wedge
The valves feature a one-piece cast flexible wedge that minimises stress concentration. Wedge flexibility ensures tight seating over a wide range of differential pressures and temperatures. It also adjusts to slight misalignments caused by pipeline deflections and thermal deformation. The stem-to-wedge thrust is applied close to the wedge centre. This reduces lateral stem loading and provides for more accurate wedge movement.
 
 
 
 
 
 
 
 
     ASME B16.34 AIL Gate,Y-Globe & Swing Check Valves
 
Pressure Seal Bonnet design
   
     

The ASME B16.34 family of AIL Gate, Y-Globe and Swing Check

Valves features a pressure seal bonnet design for high pressure

services. These valves are extensively used in high pressure and

high temperature steam, oil, gas, chemical and water applications

in thermal power plants, fertiliser plants, petrochemical plants and

refineries. The valves are available with butt-weld ends in pressure

ratings of Classes 900, 1500 and 2500, and come in carbon steel

and alloy steel construction.

Gate valves also meet the requirements of API 600 Style A.


 
     
 
GATE VALVES
       
         
Parallel Slide Disc Mechanism

This mechanism consists of two independent discs held by a disc carrier. An alloy steel spring between the discs provides the initial loading to keep the discs pressed against the body seats. The disc faces are parallel to each other and seal on parallel seat rings in the body. Sealing takes place by utilizing the line pressure to provide tight seal on the downstream seat. As the two discs are independent and parallel, opening / closing torques are significantly lower than comparable wedge disc designs, thereby minimizing the possibility of jamming at high temperatures or pressures.
When the valve is operated, the discs are allowed to slide and rotate over the body seats. This helps wipe out foreign particles from the seat faces.
   
Yoke Sleeve and Yoke Bush
     
The yoke sleeve ismade of nodularNiresis Iron,supported by a set of bearings to reduce friction and the consequent torque required to operate the valves. Nodular Niresist Iron also withstands high
 
     
temperatures. Weather seals, provided in the yoke sleeve, protect the bearing area against ingress of dirt and water.
 
 
Seat Rings
 
Body seat rings are welded to the body to offer a leakproof design as they eliminate the leakage path betwen the seat ring and the body. This design is superior to screwed seats which can loosen up due to temperature fluctuations, corrosion or vibration and result in leakage.
 
 
 
Back-seat
 
The back-seat is in-situ hard-faced with Stellite #6 or equivalent.
 
 
Accessories
 
 
AIL Valves can be supplied with accessories such as bypass arrangement, drain plugs, live-loading and mountings like extension spindles, floor stands and chain wheel. The valves can also be supplied with gear units and electrical actuators
 
       

Pressure Seal arrangement for body-bonnet joint

This pressure seal body-bonnet joint utilizes the line pressure to create a tight body-bonnet seal. Sealing is achieved by compressing a high-purity graphite gasket between the bonnet and the body retainer ring. Preloaded fasteners provide an initial tight seal at low line pressures. At higher pressures, the line pressure pushes up the bonnet against the gasket, compressing it further and providing a much tighter seal.

   
       
Trim

Both the disc and the seat ring faces are hard-faced with Stellite #6 or equivalent.
     
Stem and Gland Packing

The valves feature a stem, made of 13% Cr. Steel -ACME threaded, precision-machined and ground to a high finish to ensure a smooth operation. The high-purity graphite gland packings, used for stem sealing, provide capability to withstand high temperatures and pressures, and also to resist many chemicals. The smooth-finish stuffing box ensures longer life for the packings.
     
         
 
 
 
 
 
 
 
 
 
 
 
 
 
 
AIL Cryogenic Gate & Globe Valves
 
Services that handle fluids at sub-zero temperatures present several technical challenges. AIL's specially-adopted, extended-bonnet gate and globe valves provide the right solution for such low-temperature and cryogenic services.
AIL offers a range of gate and globe valves (as well as check valves) for low temperature and cryogenic services, used in processing, storage and transportation of liquefied gases such as Ethylene, LPG, LNG, Hydrogen, Helium, Oxygen, Nitrogen and Argon. Low temperature services of up to -460C are covered by low-temperature carbon steels like LCB and LCC materials. Cryogenic services at -1960C are covered by stainless steel grades like CF8M and CF8.
AIL Cryogenic Gate and Globe Valves are available in ASME Class 150, Class 300 and Class 600 ratings. Refer page 3 for detailed manufacturing programme.

 
   
Extended Bonnet  
   
Optional extended bonnet with vapour column length according to BS 6364 and / or customer specifications is furnished. The vapour column allows the stem packing to be functional by keeping it away from the cryogenic fluid.
 
   
Testing and Standards  
   
AIL Cryogenic Valves are type-tested as per valve standards and specifications of leading oil companies as part of the design verification process.
 
     
 
 
 
 
 
 
Angle Globe Valves - ASME Class 150 & 300
 
AIL Cast Steel Angle Globe Valves are tight sealing, easy-to-operate regulation valves for liquid and gaseous fluids over a wide range of line pressures and temperatures.

Angle Globe Valves operate in a manner similar to that of a globe valve. However, the 900 angle between the inlet and outlet pipes greatly reduces the pressure drop across the valve as compared to a conventional globe valve. These valves are used for flow control especially in systems where valve geometry or pressure drop is a concern.
 
   
Body and Bonnet

The flow to the body outlet is streamlined by the smooth curvature of the inner surface which minimises the pressure drop across the flow path. The bonnet is fitted with a bonnet bush to guide the stem and provide for back seating when the valve is open and under pressure.
 
   
Disc and Stem

The disc provides a fine bearing on a taper seal for tight sealing over a wide range of differential pressures. As the seating between disc and body seat ring is a narrow line contact, tight sealing can be achieved even if any foreign particle gets stuck to the seating area. The disc and stem are held together by a disc nut with allowance for the disc to swivel. The disc has internal threads to receive the disc nut which retains the stem with the disc. A stem thrust plate is provided between the stem and the disc
 
   
Body Seat Ring

A forged shoulder type body seat ring has threaded engagement with the body and a wide-tapered seating area. The body seat ring is tack welded to the body to prevent loosening. The seating surfaces are ground and lapped.