Jacket Insert Flanges [ Tech Data ]   Standard Insert Flanges [ Tech Data ]

JACKETED INSERT FLANGES TECHNICAL DATA

GENERAL INFORMATION

1.1 Unit Description. An insert flange unit is comprised of an insert and bolting ring (flange) and are sold jointly as one unit unless otherwise requested. Most often, insert flanges are comprised of a stainless insert and a carbon steel bolting ring, but are available in other alloys (see 5.0 Materials).

1.2 Association to ASME B16.5. References in this catalog to classes of insert flanges, e.g. 150LB, 300LBetc. designate compatibility to ASME B16.5 flanges and are not intended to denote conformance to ASME B16.5 standards. Insert flanges are not ASME B16.5 flanges. SIFCO does, however, design and manufacture insert flanges for complete bolting compatibility to ASME B16.5 flanges and offers insert flanges that meet ASME B16.5 Maximum Allowable Working Pressures in each specific class. (see 1.6, 2.1.2, & 2.2.2)

1.3 Code References. Any references to the “Code” are limited to the ASME Boiler and Pressure Vessel Code, and not other state or governmental codes which may have jurisdiction.

1.4 Established Criterion. Insert flanges for jacketed piping have been used extensively by the processing industries for more than forty years. During these years, insert flanges have established a standard for dependable service by meeting the demands of critical jacketed piping systems.

1.5 Insert Flanges Per ASME B31.3. ASME B31.3,
Process Piping, provides requirements for the design of flanges which are not listed as standards in Table 326.1, of the specification. These requirements are found in paragraph 304.5.1. This states that flanges may be designed in accordance with the Boiler Pressure Vessel Code, Section VIII, Division 1, Appendix 2 or Appendix Y, depending on whether the gasket OD is inside or outside the bolt circle. It also states that flanges may be qualified by the requirements of paragraph 304.7.2. This paragraph applies when Appendix 2 or Appendix Y are not applicable and states that the design is to be based on calculations consistent with the design criteria on B31.3 and substantiated by one or more of the following:

a) extensive & successful service experience under comparable conditions with similarly proportioned components.
b) experimental stress analysis similar to that described in BPV Code, Section VIII, Division 2 Appendix 6.
c) proof testing in accordance with ASME B16.9, MSS SP-97, or BPV Code Section VIII, Division 1, UG-101.
d) detailed stress analysis such as finite element. Since these insert flanges are very similar to ASME B16.5 flanges, containing the same ring-type elements, they can be reliably designed to Appendix 2 of the BPV Code, Section VIII, Division 1.

1.6 ASME Rated. When we refer to an Insert Flange as ASME rated we are stating that calculations conforming to the ASME Boiler and Pressure Vessel Code, Section VIII, Division 1, have been performed which determine minimum flange thickness to meet ASME B16.5 PSIG at material group 2.2 (see table 1). These calculations are based on the use of carbon steel to SA-515/516 Gr70 or SA-105 material for the bolting ring and stainless steel type 304, 304L, 316, 316L to SA-479 or SA-182 for the insert. The bolting is to SA-193-B7 and the gasket material is spiral wound. Any changes to the material, bolting, or gasket could change the required dimensions of the insert flange, if meeting the P/T rating of B16.5 is desired.

STYLES OF JACKETED INSERT FLANGES

2.1 Reducing Jacket Insert Flange. This phrase refers to the style or design of insert flange in which the nominal core pipe size is smaller than the nominal flange size. The reducing jacket insert flange style is ideal for systems in which temperature changes cannot be tolerated at flange connection. By minimizing the distances at flange connections, it assists in eliminating the frequently encountered problem of product buildup and solidification at critical points.

2.1.1 Conventional Reducing Jacket Insert Flanges.
These reducing jacket insert flanges have been used successfully for decades. This style of insert flange is only available in class 150 and 300. They utilize the economical advantage of the ASME B16.5 flange thickness for their design but are not recommended for critical applications which must meet code.

2.1.2 ASME Rated Reducing Jacket Insert Flanges.
This style of insert flange is available in all classes. On this style of insert flange calculations conforming to the ASME Boiler and Pressure Vessel Code, Section VIII, Division 1, have been performed which determine minimum flange thickness to meet ASME B16.5 PSIG values at material group 2.2 (see table 1). Therefore this style of insert flange can be used for ASME Code and Pressure Vessel Applications.

2.2 Non-Reducing Jacket Insert Flange.
This phrase refers to the style or design of insert flange in which the nominal core pipe size is equal to the nominal flange size. Non-reducing jacket insert flanges require smaller flanges. Along with the use of smaller valves and other fittings, considerable cost and space savings in fabricating jacketed systems can be realized.

2.2.1 Conventional Non-Reducing Jacket Insert
Flanges. These non-reducing jacket insert flanges have been used successfully for decades. This style of insert flange is only available in class 150 and 300. They utilize the economical advantage of the ASME B16.5 flange thickness for their design but are not recommended for critical applications which must meet code.

2.2.2 ASME Rated Non-Reducing Jacket Insert
Flanges. This style of insert flange is available in all classes. On this style of insert flange calculations conforming to the ASME Boiler and Pressure Vessel Code, Section VIII, Division 1, have been performed which determine minimum flange thickness to meet ASME B16.5 PSIG values at material group 2.2 (see table 1). Therefore, this style of insert flange can be used for ASME Code and Pressure Vessel Applications.

 

SIZE

3.1 How to Reference Size. When referencing the size of a jacket insert flange: First, designate the class and nominal flange size. Second, designate the nominal core pipe size. If it is a buttweld style indicate the core pipe schedule. Third, designate the nominal jacket pipe size with its schedule.

3.2 Nominal Size. References to the size of a flange, pipe, or bolt is its nominal size. Use of "nominal" indicates that the stated size or dimension is only for designation, not measurement.

3.3 Sizes and Classes Not Cataloged. The sizes and classes are listed due to their frequency of request and are not meant as a capacity range. Insert Flanges can be manufactured in all ASME B16.5 classes and sizes.

 

MARKINGS

4.1 Bolting Ring or Flange Markings. The edge or outside diameter of each insert flange is marked in accordance with ASME B16.5 and MSS SP-25; the manufacturer’s registered trademark, the material’s ASTM or ASME specification grade identification and the melt identification, rating class and nominal size.

4.2 Insert Markings. The outside diameter of each insert is marked, as is the bolting ring.

 

MATERIALS

5.1 Insert Material. Inserts can be manufactured from any machineable alloy. Inserts of the most popular sizes are stocked in 316L stainless steel. Other materials which have been used to manufacture inserts are: carbon steel, other grades of stainless steel, Nickel, Hastelloy™, AL6XN™, Aluminum, Inconel™, monel, titanium, and Duplex 2205™. The inserts for the ASME Rated Jacket Insert Flanges for ASME Code and Pressure Vessel Application Flanges are manufactured of stainless steel to SA-479 or SA-182 type 304, 316, 304L or 316L.

5.2 Bolting Ring/Flange Material. Bolting rings or flanges can be manufactured from any machineable alloy, but are stocked in A105 carbon steel. To inhibit rust, the carbon steel bolting rings or flanges are coated with a black enamel paint. Other coatings, such as galvanizing, zinc or epoxies, are available upon request. Other materials which have been used to manufacture bolting rings or flanges are: stainless steel, nickel, Hastelloy™, AL6XN™, aluminum, Inconel™, titanium, and other grades of carbon steel. The bolting rings for the ASME Rated Jacket Insert Flanges for ASME Code and Pressure Vessel Application Flanges are manufactured of carbon steel to SA-515/516-Gr70 or SA-105.

5.3 Mill Test Reports. Test reports from the supplier of the raw material are available upon request. Normally these test reports are available without cost.

5.4 Material Meeting ASME Code Requirements.
Raw materials are normally manufactured to ASTM standards (e.g. A-105). We also stock, or can obtain, materials which are dual certified to meet ASTM standards and the ASME Boiler and Pressure Vessel Code (e.g. SA-105). This requirement must be made known when ordering and quoting.

5.5 Domestic Only Requirement. Most raw materials inventoried are from domestic mills. If domestic material is required, this requirement must be made known when ordering and quoting to assure receiving "domestic only" material.

 

FACINGS

6.1 Flange Facings. Insert flanges are manufactured with a standard raised face to ASME B16.5 dimensions. This is the facing that will be supplied unless otherwise specified. Other flange facings can be ordered. These include, but are not limited to, large male and female, small male and female, large tongue and groove, and small tongue and groove. Due to the two piece design of the insert flange a flat face insert flange cannot be offered.

6.2 Raised Face Dimensions. Inserts are manufactured with a raised face thickness equal to the corresponding ASME B16.5 dimension. The diameter of the raised face on the inserts are equal to, or greater than, the corresponding ASME B16.5 dimension. Larger raised face diameters are found on a few of the non-reducing jacket flanges. This is necessary when a jacket pipe’s inside diameter is greater than the standard ASME B16.5 raised face dimension. However, in all cases there is adequate bolting clearance.

6.3 Flange Facing Finish. Standard facing finish for the gasket surface of the insert is a continuous spiral or phonographic finish to an average roughness in the range of Ra 125 to 250 µin. This is the facing finish that will be supplied unless otherwise specified. Other surface finishes for flange faces can be ordered. These included, but are not limited to, specified smooth or unpolished finishes (e.g. Ra 32, 63, 125, 250, or 500 µin.), or a concentric serrated surface.

 

PRESSURE TEMPERATURE RATINGS

7.1 ASME Boiler and Pressure Vessel Code calculations
To establish Maximum Allowable Working Pressure (MAWP) for the Conventional Jacket Insert Flanges. Due to the differences between these insert flange designs and standard ASME B16.5 flanges, calculations were performed to establish an MAWP Table . In some cases, values exceed the ASME ratings, and in others, values are below the ASME ratings. These calculations conform to the procedures detailed in Appendix 2 of the ASME Boiler and Pressure Vessel Code, Section VIII, Division 1. They were based on the use of standard 1/8" thick asbestos-equivalent gaskets and carbon steel bolts to SA-307 B. Flanges are forged carbon steel to SA-105 and inserts covered by these ratings may be type 304, 316, 304L or 316L. The MAWP on standard insert flanges have been established without calculating for flange protection due to overbolting using SA-193-B7 bolts. The ASME code has specifically allowed the use of alloy steel bolts to SA-193-B7 with ASME B16.5 flanges without calculation. This is primarily because ASME B16.5 flanges cannot always meet the overbolting protection requirements of the code, due to extremely high bolt strength. Since the bolting and flange thickness of conventional insert flanges are identical to those of ASME B16.5., but do not share the code’s exemption, MAWP was calculated using carbon steel bolts to SA-307 B. For piping systems using SA-193-B7 bolts, that must meet the ASME Code requirements, we have designed insert flanges which meet code requirements. (see 2.1.2 and 2.2.2)

7.2 Use of the ASME B16.5 Maximum Allowable Working Pressure (MAWP) for ASME Rated Jacket Insert Flanges.
The ASME B16.5 Pressure Temperature Ratings at material group 2.2 (see Table 1) can be used for the Jacket Insert Flanges marked "ASME Rated", for ASME Code and Pressure Vessel Application. Calculations conforming to the ASME Boiler and Pressure Vessel Code, Section VIII, Division 1, have been performed which determine minimum flange thickness to meet ASME B16.5 MAWP. These calculations are based on the use of carbon steel to SA-515/516 Gr70 or SA-105 material for the bolting ring and stainless steel type 304, 304L, 316, 316L to SA-479 or SA-182 for the insert. The bolting is to SA-193-B7 and the gasket material is spiral wound. Any changes to the material, bolting, or gasket could change the required dimensions of the insert flange.

7.3 Jacket Pipe Pressure. References to pressure temperature are limited to the pressure temperature of the process pipe. Insert flanges are not a limiting factor to the pressure of the jacket pipe.

 

WELDING DESIGN FEATURES

8.1 Process Pipe Weld Design. Insert flanges are featured with optional slip-on or buttweld designs. These represent the most requested options, but are not the only options available. Insert flanges can be manufactured with socketweld, threaded, roll-on, and tapered bores. Bore diameters are manufactured to ASME B16.5 dimensions for use with pipe to ASTM, API, and ASME standards. Insert flanges can be manufactured with bores to accommodate tube sizes.

8.1.1 Slip-on. Reference to slip-on as a type of jacket insert flange indicates that the insert will slip over the process pipe to allow front and back fillet welds. (see drawing A) If a back fillet weld is required, one end of the spool must have a section of pipe which is split and welded, or clamshell constructed.

8.1.2 Buttweld. Reference to buttweld as a type of jacket insert flange indicates that the insert will buttweld to the process pipe, allowing a full penetration V-groove weld. (see drawing "B") The welding end for the process pipe of the buttweld insert flange has a welding bevel and root face conforming to ASME B16.9 and B16.5 (see Welding Ends).8.2 Jacket Pipe Weld Design. The design of the insert at the area for the jacket pipe weld attachment varies according to the style of jacketed insert flange. 8.2.1 Reducing Jacket Insert Flanges, Jacket Pipe Weld Design. To accommodate the jacket pipe there is a 1/4 to 3/8 inch hub, machined for the specified jacketschedule. This allows for a fillet weld to the back of the insert. (see drawing "A" and "B")

8.2.2 Non-Reducing Jacket Insert Flanges, Jacket Pipe Weld Design. The non-reducing design of the insert at the area for the jacket pipe weld varies according to the size and schedule of the jacket pipe (see Non-Reducing Hub Designs). The determining factors are the clearance or distance between the nuts and the inside of the jacket pipe. These factors determine not only the design but also the length of the insert and the diameter of the raised face (see 6.2 Raised Face Dimension). To accommodate the jacket pipe there is a 1/4 to 3/8 inch hub, machined for the specified jacket schedule. This allows for a variety of fillet welds. The insert hub is designed with a stopping point or mark to indicate the intended gasket face to jacket pipe dimension.

HOW TO FABRICATE JACKET INSERT FLANGE ASSEMBLIES

9.1 Prepare Pipe and/or Weld Process Pipe.

9.1.1 Slip-on Insert Design. Measure, cut, and prepare process and jacket pipe. With bolting ring/flange and insert assembled, slip process pipe into insert and front weld end of process pipe at point A. If required, back weld process pipe and insert at point B. The assembly will require clam-shelling (see 9.3) a section of the jacket pipe if the process pipe is back welded.

9.1.2 Butt-Weld Insert Design. Measure, cut, and prepare process and jacket pipe. With bolting ring/flange and insert assembled, align process pipe to welding end of insert and weld. The assembly will require clam-shelling (see 9.3) a section of the jacket pipe when buttwelding the process pipe.

9.1.3 Transit Hub. As an alternative to clam-shell construction, we offer an optional transit hub for the jacket pipe. A transit hub allows the jacket pipe to slide further along the hub, thus allowing access to the welding area of the process pipe at the other end of the spool. If this is the preferred method of fabrication, specify this requirement when ordering. There may be an additional charge for modification. See picture to the right.

9.2 Weld Jacket Pipe. Slip jacket pipe over insert hub and weld at point C. When space allows, you may pull the bolting ring/flange back over jacket pipe to facilitate welding.

9.3 Clam-Shell. After welding process pipe to insert at point B, put clam shell section of jacket pipe into position and weld together. See Clam Shell drawing.

9.4 Align and Bolt. Rotate the bolting ring/flange to align it with its mating flange and bolt them together.