Globe Valves
A Globe valve is a linear motion valve and is primarily designed to stop, start and regulate flow. The disk of a Globe valve can be totally removed from the flow path or it can completely close the flow path.
Conventional Globe valves may be used for isolation and throttling services. Although these valves exhibit slightly higher pressure drops than straight=through valves (e.g., gate, plug, ball, etc.), they may be used where the pressure drop through the valve is not a controlling factor.
Because the entire system pressure exerted on the disc is transferred to the valve stem, the practical size limit for these valves is NPS 12 (DN 300). Globe valves larger than NPS 12 (DN 300) are an exception rather than the rule. Larger valves would require that enormous forces be exerted on the stem to open or close the valve under pressure. Globe valves in sizes up to NPS 48 (DN 1200) have been manufactured and used.
Globe valves are extensively employed to control flow. The range of flow control, pressure drop, and duty must be considered in the design of the valve to avert premature failure and to assure satisfactory service. Valves subjected to high-differential pressure-throttling service require specially designed valve trim.
Generally, the maximum differential pressure across the valve disc should not exceed 20 percent of the maximum upstream pressure or 200 psi (1380 kPa), whichever is less. Valves with special trim may be designed for applications exceeding these differential pressure limits.
High Pressure Globe Valve
A wide range of globe valves specifically designed for high pressure and high temperature applications, where low pressure loss is required.
Characteristics of High Pressure Globe Valve
- Material steel, stainless steel, cast steel, forged steel,
- Diameter-10 – 150 mm;
- Pressure from 250 up to 600 bar;
- Temperature up to 670°C (satellite ring as standard, titanium stem or other);
- Medium acids, liquors, water, steam, and other non-toxic and nonaggressive liquid and gas media, engine fuel.
- Drive type-hand wheel, pneumatic drive, electric drive;
- Ends type-butt weld or flanged
Features of High Pressure Globe Valves
- A range of compact pressure seal globe valves designed according to ASME B16.34 with wall thickness according to API 600.
- All range is offered in all the material stated in the ASTM specifications (NACE compliance included), and designed to always guarantee maximum safety and flow efficiency.
- Face-to-face dimensions as per ASME B16.10
- Available in Y and T pattern design (both also in Stop-Check configuration)
- Seat is welded-in
- The position indicator is offered as standard
- Stellite® gr.6 overlay on seat and disc; Stellite gr.21 overlay on the bonnet.
- Standard ISO top mounting for easy assembly of any type of actuator or bevel gear
- Available Options: parabolic disc, low emission packing, equalizing and overpressure pipe, limit switch in open or close position.
- Valves are offered as standard with manual operators (Hand wheel or bevel gear depending on size). Actuated options such as electric, pneumatic or hydraulic are available.
High Temperature Globe Valve
Working temperature is a key factor that should be taken into consideration for valve design, manufacture, and inspection. Generally, the operating temperature t > 425℃ valve is referred to as a high-temperature valve, but the number is difficult to distinguish the temperature range of high temp valve. High temp valve including high temp gate valve, high temperature globe valve, high temperature check valve, high temperature ball valve, high temperature butterfly valve, high temperature needle valve, high temperature throttle valve, high temperature pressure reducing valve. Among them, the most commonly used are gate valves, globe valves, check valves, ball valves, and butterfly valves. High temp valves are widely used in petrochemical, chemical fertilizer, electric power, and metallurgy industries. According to ASME B16.34, the material of the valve body and interior part are different in each temperature range. In order to ensure the valve is in accordance with its corresponding high temp working conditions, it is absolutely necessary to scientifically and reasonably design and distinguish the high temp level of the valve.
Specifications of High Temperature Globe Valve
- Size: 1 13/16” up to 30”
- Pressure Rating: API 3000 PSI to 20000 PSI
- Materials: All Material Classes as per API 6A and also Special Materials with Overlay.
- Design Standard: API 6A
- Pressure / Temperature Rating: API 6A
- Test (Inspection) Standard: API 6A
- Construction Details: Bolted Bonnet / Pressure Seal Bonnet, Non-Rising Stem
- End Connection: Screwed, Socket Weld, Flanged, Hub End, Butt-Weld
- Operator / Actuator: Lever, Gear, Actuator (Pneumatic, Hydraulic, Electro-Hydraulic, and Electric Motorised)
- Special Design Feature also available :
- Extremely High Temperature
- Cryogenic Design
- Subsea Design
Features of High-Temperature Globe Valve
- The valve cavity adopts a pressure self-tightening sealing structure, the better the sealing performance. Both ends of the branch pipe are welded structures. Welding groove can be matched according to standard or user requirements
- The sealing surfaces of the valve disc and valve seat are made of Stellite cobalt-based hard alloy, which is wear-resistant, high-temperature resistant, has good scratch resistance, and long service life
- The valve stem is tempered and surface nitrided, which has good corrosion resistance and scratch resistance.
- The depth of the stuffing box of the valve cover is reasonable, the filler is added with corrosion inhibitor, and the sealing is reliable
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