Hancock 1500, 2500 and 4500 Pound Forged ... - Industrial Controls

3. Introduction to Tee Pattern/Angle ValvesAll Hancock/Yarway valves are made to the highest qualitystandards and meet or exceed the specification, code andapplication requirements for which they are designed.Although Hancock/Yarway valves are among the mostruggedly designed products in the industry, they are stillprecision pieces of equipment and, as such, require propercare. Adherence to the handling, storage, installationand maintenance procedures contained in this manual willgreatly enhance the service life of the valve, as well ashelp ensure the safety of personnel. It is essential that allpersonnel assigned to install, operate and/or serviceHancock/Yarway valves be trained, have read and bethoroughly familiar with all the information contained in thismanual, prior to starting work on the product. In the eventthat there are any questions relative to the instructionscontained in this manual, contact our service center forclarification prior to proceeding.4. High Pressure Globe ValvesA. Design Features and NomenclatureHancock/Yarway High Pressure, TeePattern/Angle Globe Valves are "outside screwand yoke - no bonnet joint" valves. They feature aconical design plug seat, with both the disc andbody contact surfaces hardfaced with Stellite ® .These valves have a bolted gland flange, with splitgland, to provide ease in adding packing, orrepacking, the valve without removal of the stemassembly. Tee Pattern/Angle Globe valves areoffered in both loose backseat and fixed backseatdesigns. The principle design features andnomenclature for loose backseat valves (Types7130, 7170, 7230, 7270, and 7640) are shown inFigure 1, and the same information for fixed backseatvalves (Types 7150, 7190, 7250, 7290, and7650) are shown in Figure 2. Installation dimensions,applicable to both loose and fixed backseatvalves are shown in Table 1.B. Operating PrinciplesThe Hancock/Yarway Tee Pattern/Angle Valve is ofthe basic Globe Type. To operate the valve, the handleis rotated clockwise to close, and counterclockwiseto open. When the valve is to be continuouslyemployed, longer seat life may be obtained if thevalve is fully opened to the backseat, then closedapproximately 1/4 turn off the backseat.The Tee Pattern Globe/Angle Valve may also beused for throttling service. If so employed, the pressuredrop should not be more than 25% of the inletpressure. If a higher pressure differential is expected,it is advised that the Hancock/Yarway ServiceDepartment be contacted for consultation purposes.FIGURE 1—Parts ListPart No. Nomenclature1 Body2 Yoke3 Stem4 Disc5 Disc Nut6 Disc Pad7 Disc Facing (Integral)8 Seat Facing (Integral)9 Packing Gland*10 Packing Gland Flange11 Packing Gland Stud12 Packing Gland Stud Nut13 Packing Ring14 Packing Stop Ring15 Thread Bushing16 Tee Handle17 Handle Nut18 Name Plate* Split Packing Gland made from two halves.FIGURE 1—Loose Backseat Globe Valve3