RICHPAC SPIRAL WOUND GASKET

Transcription

1 RICHPAC SPIRAL WOUND GASKET Richpac spiral wound gasket consist of a V-shaped metal strip spirally wound in combination with a soft, filler material. The metal strip provides outstanding recovery, while the flexible filler guarantees excellent sealing. Due to this combination of materials the Richpac spiral wound gasket is suitable for sealing under severely fluctuating temperature and pressure conditions. Depending on the application the spiral wound gasket can be specified with outer and/or inner rings. To compliment our own product range and enhance our service capabilities we have established ourselves firmly as a supplier and manufacturer of metal gaskets. Our expertise in this area combined with superior quality control and the ability to meet critical deadlines has long been recognized and relied on by all phrases of industry. We feature a comprehensive selection of Spiral wound gaskets and sizes at competitive prices and offer nonstandard configurations, other styles and additional metals subject to special quotation. Experience has brought to our attention a general question regarding the application of metallic versus nonmetallic gaskets. As a rule we recommend employment of the following formula: Multiply the operating pressure in PSI by the operating value in degrees Fahrenheit, if the product exceeds 250,000 metallic gaskets should be considered. Spiral wound gaskets are special semi-metallic gaskets of great strength and resilience, therefore they are suitable for use under heavy operating conditions. Spiral wound gaskets are manufactured by spiral winding V-shaped metal strip and strip of nonmetallic filler material. Spiral wound gaskets can be reinforced with an outer centering ring and / or inner retaining ring. The outer centering ring controls the compression and locates the gaskets centrally within the bolt circle. The inner retaining ring increases the axial stiffness and resilience of the gasket. Spiral wound gasket should always be in contact with the flange and should not protrude into the pipe or project from the flange. Spiral wound gaskets should not be fitted between flanges with different surface finishes. Spiral wound gaskets can be used for sealing flange joints, manhole and hand hole covers, tube covers, boilers, heat exchangers, pressure vessels, pumps, compressors and valves; in industries such as petrochemicals, pharmaceuticals, shipbuilding, and food processing, energy producing industries and nuclear power stations. They are ideal for connecting high pressure piping used for steam, oil, liquids, gases, acids, alkalis, various organic and solvents. Suitable for service on the whole range of ASA 150-2, 500 series, API.601, API.605, BS.3381, BS4504, BS4865, BS.3293, MSS.SP44, DIN, AFNOR and other national standards. 1/13

2 RICHPAC SPIRAL WOUND GASKETS Temperature Pressure ph : -200 C up to 550 C with steam up to 700 C (Fire resistance up to 1000 C) : -1 bar up to 400 bars : 0 to 14 To obtain the maximum service potential, We recommend RICHPAC Spiral Wound Gaskets to be loaded to the following gasket compressed thickness: Nominal thickness 3.2 mm (0.125 ) 4.4 mm (0.175 ) 6.4 mm (0.250 ) 7.2 mm (0.285 ) Compressed thickness 2.3 mm to 2.5 mm (0.090 to ) 3.2 mm to 3.4 mm (0.125 to ) 4.6 mm to 4.9 mm (0.180 to ) 4.8 mm to 5.0 mm (0.190 to ) Gaskets fitted with inner or outer rings may be compressed to the ring thickness without damage to the sealing element. RICHPAC Spiral wound gaskets are used in petrochemical and chemical plants, and wherever in presence of high pressure, as in thermoelectrical or nuclear power plants. Refering to the AISI 304/Graphite filled gasket. 2/13

3 RICHPAC SPIRAL WOUND GASKETS TECHNICAL DATA Richpac spiral wound gasket should preferably be mounted within the following gasket stress range to ensure a leakproof connection:- FLANGE SURFACE FINISH The recommended surface roughness of the flange faces, between which a spiral wound gasket is to be mounted, is µm Ra ( RMS), also referred to as smooth finish. SPECIAL STANDARD PROFILES. The gasket is identical to RW, but fitted with an outer winding, Centering is achieved by positioning the winding over two bolts opposite each other (see illustration). TYPE D Fitted with pass-partition bars for use on heat exchangers and vessels, this gasket type if otherwise identical to RW profile. Metal-jacketed bars generally have a thinner design than that of spiral wound gasket components. The bars are usually fixed through microplasm welding or silver soldering. The welding method is chosen depending on the gasket material. pr Fitted with an outer centering ring. The E is otherwise identical to the D profile. Fitted with an outer centering ring and an inner ring, the F is otherwise Identical to the D The G is a highly specialized type of gasket, consisting of RICHPAC camprofile gasket and a RICHPAC spiral wound gasket separated by a perforated intermediate ring. The sealing layers on the camprofile and the filler of the spiral wound gasket are made of identical material. The perforated intermediate ring is flushed with inert gas (such as nitrogen) This design enables the operator to measure any leakage, making the gasket suitable for us in critical applications where a high degree of gastightness and operational reliability is required. In order to manufacture the above gaskets, we require a drawing specifying the exact dimensions and position of the bars 3/13

4 PROFILE WITH SPE-ZONE In the event of a graphite-filled spiral wound possibly causing an undesirable reaction between graphite and the medium to be scaled, or of possible medium contamination, the problem can be solved by using spiral wound gasket with a SPE- ZONE. The spiral wound element of a SPE-Zone gasket consists of outer windings of non asbestos or ceramic material with a central winding zone made of graphite or PTFE (depending on the operation conditions) to improve gastightness, see illustration. This result in a spiral wound gasket with the following properties: Does not pollute the sealed medium Excellent gastightness Conbined with the outher advantages of a spiral wound gasket, the spiral wound with SPE-Zone may be used in a wide range of operating conditions. SPECIAL SHAPES Spiral wound gasket can be produced in a wide wariety of shapes, such as oval and pear-shape, with pass-partition bars and many other types. Generally, the pass partition bars on spiral wound gasket are metal-jacketed bars. TYPE H This spiral wound gasket is identical to the RW profile but oval shaped to fit manholes. TYPE I This type of gasket is for hand holes and special flange assemblies (tube cap and hand hole covers). They are available in e.g. square, rectangular, oval diamond and pear shapes. A drawing specifying the correct dimensions is required to manufacture special shapes. For spiral wound gaskets with straight sides (e.g. for gate valve bonnets)we recommend that an inner ring be used if the length/width ratio>2.

5 MATERIALS With the proper selection of metal and filler materials, Spiral wound Gaskets may be used under different operating conditions for different types of flanges. OUTER CENTERING RING The outer centering rings are made from low-carbon steel, with electroplating, galvanized, or painted surface to protect them from corrosion. RICHPAC can also manufacture them on request from other materials. INNER RETAINING RING The inner retaining rings are usually made from the same material as the metal spiral winding

6 SHAPE AND CONSTRUCTIONS RICHPAC spiral wound gaskets commonly have a round shape, but can be made to oval rectangular. Square with round edges etc or those with a loop centering guide. FILLER SELECTION FILLER MATERIAL The table below may be used to select the correct filler, it should be pointed out that graphite will be the optimum filler in most cases. Only where graphite could cause media pollution, or is not chemically resistant, should the use of another type of filler material be recommended. In such cases, an alternative solution might be to use a gasket with SPE-Zone.

7 GASKET THICKNESS BEFORE AND AFTER FITTING Depending on the diameter, the spiral wound gasket is available in a variety of thicknesses. The table below specifies the thicknesses and the recommended optimum thickness after fitting. SELECTION OF GASKET THICKNESS The spiral wound gasket is usually produced with a thickness of 4.5 mm. However, in some cases a different thickness may be selected to obtain effective sealing. The table below specifies gasket thickness for certain applications. PRODUCTION TOLERANCES The table below specifies the production tolerances for Richpac spiral wound gasket

8 FOR BS 1560 AND ASME/ANSI B16.5 FLANGES In accordance with gasket Standard ASME B16.20 (API 601)

9 FOR ASME B16.47 SERIES A (MSS SP44) FLANGES In accordance with gasket Standard ASME B16.20 (API 601)

10 FOR DIN FLANGES In accordance with standard SPW1

11 FOR FLANGES IN ACCORDANCE WITH DIN 2512 Tongue/groove flange shape TYPE IRW, RW In accordance with gasket Standard DIN 2691 (PN10-160)

12 RICHPAC SPIRAL WOUND GASK FOR FLANGES IN ACCORDANCE WITH ASME/ANSI B16.5 MALE/FEMALE FLANGE SHAPE, TYPE : RW in accordance with SPW3 (150lbs. 1500lbs.) TONGUE/GROOVE FLANGE SHAPE, TYPE : RW in accordance with SPW4 (150lbs.-1500lbs.)

13 RICHPAC SPIRAL WOUND GASKET FOR ISO 7005 FLANGES In accordance with ISO standard 7483.