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MATERIAL SPECIFICATIONS INSTALLATION Body: 1/2" to 11/4" (13mm-32mm), forged steel, ASTM All Hansen welded valves can be installed in horizontal A105; 11/2" to 18" (40mm-450mm), cast steel, ASTM or vertical pipe lines. Stems are normally installed A-352, Grade LCB horizontally, but, depending on the application, stems Bonnet: Ductile iron, 1/2" to 8" (13mm-200mm) ASTM may be installed vertically. Inlet pressure or direction of A-536; 10" to 18" (250mm-450mm) flow for all valve sizes should normally be under valve ASME SA-395 seat disc. However, to avoid installing an angle valve Stem: Polished stainless steel with the stem down, it is better to install the valve with Disc Holder: Plated steel the normal flow opposite the direction of the arrow. For Seat Disc: Retained PTFE Teflon pressure differences exceeding approximately 125 psi (9 bar), valves 8" (200mm) and larger should have inlet Ball Bearings: Stainless steel pressure above valve disc, using a small bypass valve Packing Nut: Zinc plated steel for preopening equalization. Stem Packing: Graphite composite plus neoprene Care must be taken when handling and installing large O-ring in series valves. Proper lifting devices and safety precautions Handwheel: 1/2" to 1'/4" (13mm-32mm) Zinc plated alloy; must be observed. 11/2" to 6" (40mm-150mm) Zinc plated iron alloy; 8" to 18" (200mm-450mm) cast aluminum A valve should have its bonnet assembly removed before Seal Cap: 1/2" to 1'/4" (13mm-32mm) Glass-filled welding. This reduces weight during welding, protects polymer, safety vented; 11/2" to 4" (40mm-100mm) the Teflon seat disc from welding sparks,and facilitates Zinc plated steel; 5" to 18" (125mm-450mm) cast cleaning of welding debris from the body interior prior aluminum to valve operation. The valve stem should be several Operating Temperature: turns open when removing and replacing the bonnet assembly. The Teflon seat disc should be protected Standard, -60°F to 240°F (-51°C to 115°C), when outside of the valve. Do not allow the Teflon seat temperatures below-60°F (-51°C) to-76°F (-60°C) to bump the valve body when removing it or stand the at coincident pressures bonnet on the seat disc. Optional,-20°F to 300°F (-29°C to 149°C) contact factory Where it is necessary or standard practice to weld a valve Safe Working Pressure: 400 psig (28 bar g) standard, into the line without bonnet removal,the stem should be 600 psig (41 bar g) upon request opened several turns to prevent heat damage to the seat disc. Extra care should be taken when welding angle Connection Dimensions: 1/2" to 1 1/2" Match Schedule valves without disassembly to avoid welding sparks 80 pipe, 2" to 10" Match Schedule striking the seat from the outlet weld connection. 40 pipe, 12" & Up Match Standard Weight Pipe Use of welding rings is recommended. They help ADVANTAGES alignment, control the gap for full penetration welding, Compared to conventional stem seal designs, Hansen's and reduce the potential of welding debris entering patented no leak seal-plus-stem-packing virtually the system. Welds should be annealed as necessary eliminates stem seal leakage. In addition, the stem is in accordance with good practice. Painting of valves polished to avoid packing wear. The precision stem and welds is recommended for corrosion protection. threads avoid stem wobble and the packing nut is close Pipe covering, where applied, should have a proper fitting to remove dirt particles and frost from the stem. moisture barrier. This results in infrequent maintenance or tightening and almost no refrigerant loss. Before putting valves into service, all pipe weld connections,valve seats, bonnet seals,and stem seals Hansen valves are designed with anti-spin seat discs. should be tested for leaks at pressure levels called for High velocity gas can sometimes cause ordinary seat in appropriate codes. discs to fail over time.Hansen adds a snubber to prevent the seat disc from freely rotating when valve is in the Shut-off valves leading to the atmosphere must not be open position. left unsupervised and must be plugged or capped to Compared to threaded valves, Hansen welding valves prevent corrosion inside the valve as well as leakage eliminate the chance of future leaks at pipe threads. In due to seat expansion, vibration, pressure shock, or addition,a butt weld pipe-to-valve body joint eliminates improper opening.Where hand wheel valves are subject the inherent weakness and corrosion vulnerability of to excessive vibration or liquid shock loads,the packing the threaded portion of pipe immediately adjacent to a nut should be tightened to prevent handwheel vibration screwed valve body or flange. from potentially rotating valve stem. The valve seat Compared to ball valves, Hansen welding valves have no should be cracked open to prevent hydrostatic expansion threaded or flanged-gasket pipe joints. Hansen valves between the valve and the cap.A bleed valve and gauge also will not open or close so rapidly as to cause severe should be installed to provide a means of monitoring and pipe shock due to sudden change in liquid velocity. In pump-out.Valves should never directly feed a water tank addition, ball valve stem packing typically cannot be because of potential internal corrosion or seat opening replaced while the valve is in a pressurized line.The stem caused by vibration. packing on these Hansen valves can be replaced while the valve is in a pressurized line.Also, dirt or damage to ball valve Teflon seats cannot be overcome by greater stem closing forces, an advantage of Hansen valves. G359d 2 NOV 2019