8.1 Valves shall comply with the relevant standards and codes as specified herein and in the valve data sheets.
2 Ball Valves
All ball valves shall be of a fire tested design to BS6755 Pt 2, API 6FA or API 607,certified accordingly and fitted with fire safe seals.
Valves shall be of anti-static design with blow out proof stems.
The design of all ball valves shall incorporate body cavity pressure relief, which shall be achieved through seat design. A hole drilled in the ball to achieve body cavity relief is not acceptable.
Ball valves shall be reduced bore pattern, unless otherwise specified full bore on the individual data sheets. Reduced bores shall be limited to one line size smaller than body size.
All balls shall be solid, one piece design.
Where a 6.0mm corrosion allowance is specified in the valve data sheet, valves shall include a 316 SS weld overlay on seat pocket areas.
3 Gate, Globe, Check and Needle Valves
Regular port design shall be supplied unless noted otherwise on the individual valve
Gate, globe and needle valves shall be suitable for re-packing under pressure in the fully open position.
The direction of flow shall be cast or steel stamped on globe valve and check valve bodies and on uni-directional valves. Low stress stamps must be used where required.
4 Butterfly Valves
All butterfly valves shall be fully lugged type with holes through drilled and tapped
ASME B1.1 coarse thread series 1” diameter and smaller and 8 thread series 11/8”diameter and greater.
The valve supplier shall stipulate the number and length of bolts required for each size and type of valve where partial penetration tapped holes are used in their design.
Valves shall be suitable for installation between ASME B16.5 RF flanges 3” to 24”NPS and ASME B16.47 Series A RF flanges greater than 24”NPS, up to and including Class 600lb
For rubber lined valves the Vendor shall submit with bid, full details of how the liner is locked into the body, and how it is sealed around the valve stem.
The Vendor is responsible for checking the liner and seal rings suitability for the design conditions and service fluids stated on the valve data sheets. Confirmation of the suitability shall be stated in the Vendor’s bid.
Where specified on the data sheet, valves shall be of a fire tested design to BS6755 Pt 2 or API 607, certified accordingly and fitted with fire safe seals.
5 Hot Oil Service Requirements
Where specified on the valve data sheet, valves shall be suitable for hot oil service and have a previous history of use in this service, details of which shall be submitted with bid.
VALVE OPERATOR REQUIREMENTS
1 Levers and handwheels on valves including gear operators shall be permanently marked “OPEN” or “CLOSE” with an arrow to indicate direction of rotation.
2 Where stated on the valve data sheet, valves shall be fitted with a facility for locking in the open or closed position. Locking shall be achieved by the insertion of the shank of a standard padlock. Keys and padlocks will be supplied by ‘others’.
3 All valves shall be suitable for the retrofitting of Valve Interlocks after installation at site, by others, without affecting the pressure envelope of the valve or valve manufacturers warranty. The Vendor shall be responsible for liaison with the selected interlock manufacturer to ensure compatibility of valve and locking device. All valve topworks details required by interlock manufacturer shall be supplied by Vendor free of charge.
4 Valves shall be capable of satisfactory operation with the valve stem in any position i.e. vertical, horizontal or inclined.
5 Valve operators shall be as stated on the valve data sheets provided the torque or direct force does not exceed 350N under maximum differential pressure. Where this torque is exceeded the Vendor shall highlight this in the bid.
6 Wrench & Lever Operators
6.1 Wrench and lever operators shall be fitted with stops at the fully open and closed positions to prevent the ball or blades moving through more than 90°. These stops may be raised bosses, integrally cast or forged with the valve body. Preferred location for the plate, which strikes the stops, is permanently attached to the stem as opposed to attached to the wrench, which may be removed allowing mal-operation. 6.2 Butterfly valves shall have lever locating spigots and holes at intermediate points of their travel to regulate the flow as well as at the fully-open & fully-closed positions, this is not a locking device unless otherwise called for in the valve data sheet. 6.3 Valves shall be fitted with the facility of a stem extension to clear insulation if stated in the valve data sheet. Valves shall also be suitable for retrofitting vendor’s extension devices at site.
7 Gear Operators
7.1 Bevel or worm gear types shall be complete with handwheels and position indicators. The operators shall be weatherproof, totally enclosed and packed with suitable lubricant. Where the units are not “sealed for life” they shall be suitable for re-packing with grease whilst the valve is installed in line. Gear operators shall be mounted in such a way that they can be easily unbolted from the valve body and subsequently be repositioned in 90°increments.
7.2 Gear operators shall be of such a design that the valve can be fully opened and closed with a correct flow passage. For ball and butterfly type valves the gear operator design shall prevent the ball or blade turning past the 90° fully open or closed position.