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コントロールユニット Cameron DemcoのPDF インストレーション、オペレーション＆メンテナンスマニュアルをオンラインで閲覧またはダウンロードできます。Cameron Demco 11 ページ。 Resilient-seated butterfly valve

END-OF-LINE SERVICE

DEMCO tapped lug butterfly valves are suitable for liquid service end-of-line applications with downstream piping

removed (Figure 7). Sizes 2"-12" are suitable for 200 psi, while sizes 14"-36" are suitable for 150 psi. Weld neck (all

sizes), slip-on (sizes 2"-12") and socket weld (sizes 2"-12") flanges can be used for this service. Since the upstream

pressure is excluded between the flange and the seat face by the exclusive DEMCO flange seal, there is no effective

force to slide the seat downstream.

Caution: the valves must not be opened or closed with the downstream piping removed as the seat might be

shifted breaking the flange seal and allowing pressure to slide the seat downstream.

Figure 7

Flange gaskets are not required nor recommended for use with positive shut-off DEMCO Resilient Seated Butterfly

Valves. An integral flange seal is molded into the edge of the rubber seat eliminating the need for flange gaskets.

Throttling Valves, only, utilize an O-ring stem seal that must be assisted with flange gaskets for a proper seal.

Steel ASME Class 150 (or MSS SP-44) weld neck flanges are suitable for all sizes. Slip-on, threaded and socket weld

– as well as "stub end" type C flanges – are suitable for use with 2" thru 12" DEMCO Resilient Seated Butterfly

Valves. 30" and 36" DEMCO Resilient Seated Butterfly Valves fit between ASME 125/ASME 150 Series A Flanges (or

MSS SP-44).

Other flange types may be applicable also, but should be thoroughly checked to assure proper seal makeup. Plastic

flanges are subject to damage at installation by over-tightening the bolting and may defect or "cup" resulting in

flange leaks.

Recommended bolt and stud lengths for installation in ANSI flanges are provided in Table 4.

TC-003001-01 / Rev 2