DEVELOPMENT OVER THREE GENERATIONS   In 1961, an Australian inventor and valve manufacturer, Malcolm Tarlton Phillipps, designed and patented a very simple fixed ratio pressure reducing valve, enabling excessive water pressure to be reduced to acceptable limits. A few years later, his son Malcolm Wheatley Phillipps designed and launched a Mark II series that had vastly improved flow capabilities, was significantly smaller in size and lower in cost. Now Guy Malcolm Phillipps, founder of Guyco, an Australian company, has followed the tradition of his forefathers with the release of a new range of valves incorporating three generations of knowledge and experience. Fixed ratio type valves have been installed in high-rise developments since the 1960’s. There are countless valves installed in buildings in Australia, Hong Kong, China, Singapore, South Africa and the United Kingdom. Precision Engineered for Reliability The Guyco ratio valve has only one moving part, a 316 stainless steel piston. Compare this to the more vulnerable diaphragm-type valves. The bore and piston have been manufactured with precision running fits. Naturally, Guyco valves are manufactured from high-grade materials under strict quality control conditions. N.B. Standard ratios are; 1.5:1 (3:2), 2:1, 3:1, 4:1 & 5:1. Other combinations are available on request; e.g. 3.2:1 or 2.4:1.   Applications Anywhere there is a need to reduce or control pressure! High rise buildings – flusherette, cold water and fire hydrants Mines Oil rigs High-pressure urban areas Mountainous terrain Huge Cost Savings The Guyco ratio valve eliminates the need for pressure breakdown tanks. This means huge savings for developers of high-rise buildings in terms of space, construction and maintenance costs. Head Loss Sleek design and superior fluid dynamics ensures minimal head loss through the valve.   Security The valve setting cannot be tampered with or incorrectly adjusted. Easy Maintenance The compact size of the valve allows for easy servicing and the rubber seat, o-rings and seals are readily available. They should require servicing every 3 to 5 years. Easy Installation Guyco valves can be installed in any position, from vertical through to horizontal. The breather hole has a threaded off-take. This is to allow for a light flexible tube to be connected to the valve so that it can be buried underground or installed in ceiling spaces.   Five-Year Guyco Guarantee All Guyco Ratio Pressure Reducing Valves are fully factory tested and guaranteed against faulty workmanship and parts for a period of 5 years from date of manufacture. SPECIFICATIONS & PERFORMANCE   Valve Selection - The Guyco valves are manufactured in accordance with BS EN 1567:2000. Valve selection should be determined by the pipe size, flanged and screwed thread details to the appropriate standards, desired ratios and where possible, the flow requirements. Specify =Body control size =Ratio =Flange size   =Flange table =Thread standard Ratio Selection - This is achieved by determining the inlet pressure at the entry to the valve and the desired outlet pressure. In fixed head situations, the inlet pressure can be easily calculated. Ratio accuracy to within plus or minus 5%. Once a valve has been specified, it is unlikely that it will need changing. However it is possible to alter the ratio by interchanging the piston and outlet spigot. This is a very simple process. Flow Data Flow is unaffected by ratio. Flow charts illustrated below were carried out by the Australian Irrigation Technology Centre (a NATA approved laboratory). Performance curves were produced while maintaining a fixed inlet pressure. N.B. For further details contact Guyco – email: sales@guyco.com.au Operating Inlet Pressure Minimum operating pressure – 200kPa (30psi) Maximum operating pressure – 3,500kPa (510psi) Temperature Range For cold water applications from 5°C (40°F) to 80°C (175°F) Identification All Guyco flanged valves and screwed valves 40mm and above, carry a serial number for traceability. Assembly Details For dimensions and parts list, refer to tables and illustrations.   FLANGE SERIES (mm) Body Size Flange Size Dimension 'A' Dimension 'B' 50 50 50 80 80 100 100 150 65 65 80 80 100 100 150 150 135 135 135 205 230 200 200 230 165 185 205 205 230 230 305 305   SCREWED SERIES (mm) Body Size Thread Size (BSP) Dimension 'A' Dimension 'B' 12 20 25 32 40 50 65 1/2" 3/4" 1" 11/4" 11/2" 2" 21/2" 94 99 110 134 140 177 207 38 44 55 72 85 99 124 DESIGN CONCEPT With only one moving part – a piston – the Guyco Ratio Pressure Reducing Valve is perfection in its simplicity. Configuration The piston determines the ratio of the valve. Ratios can be altered simply by changing the piston and outlet spigot to the desired combination. i.e. 1.5:1 (3:2), 2:1 & 3:1. Higher ratios are obtainable if required, but not generally recommended as valve noise may be encountered. Other combinations are available on request; e.g. 3.2:1 or 2.4:1. Sleek Design Sleek design and superior fluid dynamics ensure minimal head loss through the valve. The cut away illustrations of the screwed and flanged valves in the open and closed position demonstrate the streamlined flow. Body - Flange Series The valve body has been manufactured from a copper based alloy – Type LG 2 to BS 1400. Flanged Series Flexibility in manufacture enables flanges of various international standards to be accommodated i.e. BS 4504: section 3.3: 1989. Body - Screwed Series The 65mm screwed valves have been manufactured from a copper based alloy – type LG 2 to BS 1400.  The 20mm – 50mm screwed valves are manufactured from DR brass. Screwed Series Flexibility in manufacture enabled thread forms of various international standards to be accommodated.  Standard valves have threads manufactured in accordance with BS 21. Inlet Spigot Made from the same material as the body and has been designed with only three webs and shaped to minimise head loss. Seat Made from nitrile rubber.  For potable water applications, materials used comply with BS 6920.  If minor wear or damage occurs, it is possible to turn the seat over to extend its life. Seat Retainer Made from the same material as the body and has been designed in the shape of a reverse cone to increase the piston stroke in low flow conditions.  This ensures long-term durability of the o-rings and minimises the risk of noise in high-pressure reduction situations. Piston Precision engineered for accuracy and manufactured from 316S31 stainless steel material in accordance with BS970; part 1.  The piston face used in the flanged valves has been carefully machined to a pre-determined radius to minimise turbulence and eliminate noise emission during the opening and closing stages of the valve. Outlet Spigot Also made from the same material as the body, and is designed to suit the specific ratio.  It can be simply changed over if required. Breather Hole Has a ¼” threaded take-off to enable connection of a drain tube or vent. O-Rings and Seals Manufactured from nitrile rubber in accordance with BS6920 and is suitable for potable water. Special Coatings The bore and pistons are available with PTFE (Teflon) coatings on request.