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More than a century of pioneering and development in the field of high pressure/high temperature valves for critical services has kept Hancock the industry leader in Steel Gate, Globe & Check Valves, Sizes 50 - 600mm ASME Class 150, 300 and 600.
Cast Steel Gate Valves
A straight through, unobstructed flow passage, combined with metal-to-metalseating, makes the Hancock gate valve the ideal choice for applications wherehigh velocity or highly viscous fluids must be handled with minimum flow loss.Excess pressure drop caused by abrupt changes in flow path direction, changes incross section and friction or turbulence are minimised. Fluids pass directly through the valve, in a straight line, at the lowest possible velocity, without impinging on the internal flow passages or seating surfaces. This prevents seat and/or body erosion damage.
- All internal surfaces are accurately machined to provide maximum performance.
- Renewable body seat rings are made from hardened stainless steel, faced with stellite.
- The wedge is cast, hardened,ground, and lapped to ensure positive sealing
- Fully guided wedge, precisionmachined body channels, foraccurate, repeatable seating alignment.
- Code compliance with ASME/ANSIB16.34, API 600 and API 603.
Cast Steel Globe Valves
Positive contact, metal-to-metal seating, make the globe valve ideal for most shut-off applications. The basic design eliminates the inherent problem of “wedges ticking” common in wedge gate valves caused when high thermal transients orpiping load stresses exert such force that the valve won’t open. The contoured disc allows for accurate control over the initial portion of stem travel, permittingsmooth, linear flow, thereby preventing mechanical and/or thermal shock to thevalve, down stream piping or expensive machinery.
- All internal surfaces are accurately machined to provide maximum performance.
- The disc is hardened, ground, and lapped to ensure positve and repeatable sealing over the valve’s full pressure/temperature range.
- A precision machined backseat is standard.
- Seats are designed for accurate,repeatable, seating alignment.
- Corrosion inhibited graphite packing and braided graphite filament anti-extrusion rings are standard.
- Code compliance with ASMEB16.34 and BS1873.
Cast Steel Check Valves
Swing check valves are primarily used to prevent flow reversal in piping systems.They are designed to close automatically with positive shut-off in either horizontal or vertical pipe systems.Swing check valves have a low pressure drop and are best suited for moderate velocity applications. Correct sizing of swing check valves is important, with either too low or too high a velocity potentially damaging valve internals and shortening valve life. For best performance, swing check valves should operate with fluid velocity sufficient to hold the disc fully open against the disc stop, or fully closed.
- Flat, precision machined and lapped seating surfaces eliminate damage from high impact seating.
- All internal surfaces are accuratelymachined to provide maximumperformance.
- Code compliance with ASME/ANSIB16.34 and BS 1868
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