AE

A Abrasive wear Abrasive wear removes material inside the valves and / or piping. In the case of flowing media with abrasive wear materials, this material removal must be prevented by suitable measures, such as specially hardened surfaces of the wetted parts. Abrasive substances are, for example, quartz sand, ferrite slurries, but also coffee powder, etc. Shut-off valve: An armature, the primary function of which is the shutting off of a medium. A regulation is not provided. Typical shut-off valves are taps such as ball and cone taps. Closing body Moveable part of a fitting whose position in the flow path allows, restricts or obstructs flow. Erosion, electrolytic = electropolishing A special type of surface treatment. In contrast to hand polishing, electropolishing is not a mechanical removal, eg by grinding. An existing surface structure is smoothed - the "peaks" and "valleys" of the surface are aligned as far as possible. The electropolished surfaces are less susceptible to material accumulation and thus to attacks of the material by the medium. Applications mainly in biochemistry. Pharmacy and in the food sector. Adhesive wear Adhesive wear - adhesive, adherent - is a material transfer, seizure or cold welding. This gives off by plastically, microscopically small surface deformation of the roughness mountains created by processing of bodies sliding past one another. Type of suspension For valves with a mounted end body, the seals must be pressed against them. This is done by means of spring elements. Spring elements can be: spiral or disc springs, spring assemblies, graphite discs, etc. Recognition test Inspection performed in accordance with technical specifications in the order. Requirement profile The requirement profile for a valve specifies its use as precisely as possible in the subsequent system. On the basis of the requirement profile, valves can be designed precisely with regard to pressure, temperature and medium. We should be defined as precisely as possible in the system design. Antistatic design A fitting design which ensures the electrical conductivity between all wetted parts and the pressure-bearing housing. Venturi fitting with valve seat less than 90% seat bore diameter and not less than 60% of the nominal inside diameter of the housing end ports Full bore fitting (integral) Valve with a seat bore diameter not less than 90% of the nominal -Interior diameter of housing end ports Valve without actuator Valve consisting of pressurized housing, equipment and seal of the actuator suitable for mounting the actuator NOTE: The boundary between the valve without actuator and the actuator is specified in the corresponding design standard. Armature, metallic sealing in the metal-sealed armature is used as a sealing materials, a metallic material. Applications are all cases where soft seals such as PTFE, PE, TFM, etc. could be damaged. High temperatures or abrasive media can be examples of this. Fittings, fully welded fittings that are laid underground, for example, are often used in the fully welded version. A tightness to the outside is guaranteed, a possible loosening of housing screws can not take place. In case of repair or maintenance, the complete valve is replaced. Valve class Classification of valves, mostly according to their purpose in different classes. Fittings listed within these classes equally meet all conditions imposed on them, such as media compatibility. Valve test bench Test stand for testing the tightness of the valve both in the passage and in the surroundings as well as the functions of a valve such as actuation, torque, etc. Valve approval Approval for specific, precisely defined valves for a specified area of application. In the areas of the assets subject to acceptance, this may, for. At present, the TÜ.AGG for mobile systems and / or pressure vessels (tankers, silos, etc.), the TÜV.AR for stationary monitoring systems. Asymmetrical fitting A fitting whose inside contours are not symetrical to any plane perpendicular to the axis of the housing end openings. On (inlet) / downstream side The upstream side (also on the upstream side) identifies the inlet side of the flow into the valve, the downstream side identifies the outlet side of the valve. On / Off function Fittings that are used for the pure shut-off of media flows fall under the scope of the open / close fittings (shut-off valves). These are usually not suitable for other applications such as regulations, since they do not have a well-defined control characteristics and could be damaged when used as a control valve possibly in the area of the seals. Blow-out design Valve design that ensures that the valve actuator of a pressurized fitting can not be pushed out of the pressure-bearing housing when an external part is broken down. External spindle thread The spindle moving thread that is not in contact with the flow medium inside the valve. Design data The key data for which a particular valve or valve type is designed. The manufacturer usually guaran- tees trouble-free operation of the valve if it is operated within the design data. Design data are eg pressure / temperature limits. External spindle thread The spindle moving thread that is not in contact with the flow medium inside the valve. Automation For cost reasons, to save operating personnel and to simplify monitoring, more and more systems are being automated. Operations within the plants can thus be controlled remotely and remotely. Operating personnel can work and monitor safely through automation outside hazardous plant areas. Design The design of valves is regulated in EN 736 with parts 1 - 3 and initially describes the valves according to the types and functions. Overall length ETE The distance, in millimeters, between the faces of the housing end openings for through-hole fittings with connections other than flanged connections. Overall length CTE The distance in millimeters between the end face of one end of the housing and the axis of the other end of the housing for corner fittings with connections other than flange connections. Heating / Isolation Media that need to maintain a certain temperature within the piping are routed through insulated piping and fittings. If this is necessary over longer distances, the pipeline and fittings must be additionally heated. This is done by heat tracing, usually by steam or electric heating coils. Load principle Description of the actuation of the main valve. When loading principle, the safety shut-off valve is closed by applying pressure, ie via the safety valve pressure is applied to a drive piston, whereby the valve is closed. Notified body The body that is authorized to accept or monitor compliance with the conditions and tests in accordance with the PED. Rupture Disk Device A non-reclosable pressure override device responsive to differential pressure and designed to function by rupture of the rupture disk (s). It includes the complete unit of built-in components, possibly including rupture disc holders. Coating A protective layer applied to a fitting part or fitting to protect it from corrosion and / or to prevent contamination of the medium by the fitting. Actuator part of the actuator, through which the mechanical energy is supplied. NOTE: It can be mounted directly on the valve without actuator. Moment of actuation Moment which is applied to the actuating device and which is necessary to actuate a valve under fixed operating conditions between open and closed position. Actuator mechanism which transmits the movement of the actuator to the closure body, moving linearly. Actuator Operated by hand or by external power device for actuating the valve without actuator. Activation Time The time it takes an open / close valve from the 100% open position to the 100% closed position. In the control valve, it is the time needed to reach an operating point. In general, it is the time during which an Armatru is operated. User Inspectorate In derogation from the provisions on the tasks of the notified bodies, Member States may allow pressure equipment and assemblies whose conformity with the essential requirements has been assessed by a user inspectorate in their territory to be placed on the market and put into operation by the operators. Operating parameters All parameters that may occur during the operation of a system - and possibly at the same time. For valve design, the operating parameters must be specified as accurately as possible. These are mainly pressure, temperature, Durchflußmegen but also the indication of differential or control pressures. Biotechnology The term Boitechnologie basically describes the variety of technological processes for the production of drugs for pharmaceutical applications using biological crops. With regard to the purity and surface quality, special requirements are placed on valves and pipelines in the field of biotechnology plants. Bubble Counters Counters are most commonly used in conjunction with a bubble trap to detect leaks. Bubble counters can be designed as accessories for valve test benches or as individual devices. CE mark Conformity mark of the manufacturer. The CE mark indicates that a device - in the field of valves, usually a pressure device or a piece of equipment of such a device - complies with the rules of the art and / or certain test requirements. The basis for this is the PED. CIP Designation of a fitting that must not be removed from the piping system for cleaning inside (Clean-In-Place). Separate flushing connections make it possible to rinse, sterilize or dampen the valve dead zones even during the operation of the valve. Steam control valve Thermally heavy-duty valve for steam control. The sealing elements are designed in these fittings so that they can not be damaged or deformed by the control process at the usually very high flow velocities. PED (PED) The Pressure Equipment Direction Line (PED) currently governs. all areas of pressurized containers and pressurized attachments. Within the framework of the CE marking, the PED is replaced by the Pressure Equipment Directive (PED) 97/23 / EC and its possible appendices. Diamond coated ball Ball with special surface coating. This achieves a hard and therefore wear-resistant spherical surface. Diamond coated balls are often used in conjunction with metallic sealing cups. Sealing force Force that must be transmitted through a fastener - usually one or more screws - so that a connection remains tight. The tightness retention force also results from the additional force required for the compression of seals. Tightness in the seal The tightness in the seal describes the degree of tightness of a valve when the shut-off element is closed in the flow direction. The definitions of tightness are regulated in DIN 3230 T 3 "Leak rates" ff. Sealing ring bushing, which receives the or the sealing ring (s) in a soft-sealing seal of the actuator. Gasket, chambered Constructive measure in which the actual gasket is gripped in a groove or in an inflexible shape. Chambering is mainly used for soft seal materials that are prone to deformation due to difficult operating conditions. By chambering these deformations are largely avoided. The main group of sealing materials includes, among others, the families of elastomers, polymers, thermoplastics, etc. Differential pressure Differential pressure refers to the pressure difference in front of and behind a valve. The height of the differential pressure can have a significant influence on the operating torque in valves and must therefore be taken into account, for example, in the drive design with. DN (nominal size) A numerical definition of the size (see note), which is the same for all components of a piping system, in contrast to components that are defined by an outside diameter or by a thread size. It is a round number (approximately the inner diameter of the pipe connection measured in millimeters). It usually refers only approximately to the manufacturing dimensions. NOTE 1: It is identified by the letters "DN" followed by a number from the following series: 10, 15, 20, 25, 32, 40, 50, 65, 80, 100, 125, 150, 200, 250, 300, 350, 400, etc. NOTE 2: Nominal diameter DN can not be used for measurements and can not be used for calculations. NOTE 3: Some older international standards refer to nominal diameter as the nominal diameter, but the two terms are identical for this standard. NOTE 4: The definition of the nominal size is in accordance with ISO 6708. Rotary vane drive Drive variant in which the movement of the selector shaft is effected by applying air, liquid or other suitable medium to blades mounted on the shaft. Another drive variant is the double-piston rotary actuator. Rotary Cone Valve A valve with a throttle body that can be cylindrical, conical, or an eccentric spherical segment. Torque Force to be transmitted through a shaft required to operate the valve. The specification of the torque of a valve is indispensable for the design of a drive. The shaft must be dimensioned so that it can transmit the required torque plus safety, without being damaged. Unit is Nm (Newton x Meter) Throttle body, multi-stage The movable part of the valve that is in the flow to restrict the flow through the valve. A throttle body may be a cone, a sphere, a disk, a wing, a plate, a diaphragm, etc. Pressure sealing connection Connection of housing with upper part or cover, in which the internal pressure of the flow medium, the deformation force of the upper part seal or cover seal or the self-sealing ring. Pressure relief hole The pressure relief hole is located in the upper part of the ball - at the intervention of the switching shaft - and connects the dead space between ball and housing with the pipeline. This results in the dead space in the same pressure as in the pipeline itself. The pressure relief hole prevents uncontrolled pressure increase in the dead space with open fitting. See also -> Degassing Drilling Pressure Equipment Directive Regulates the equipment and design of pressure equipment. It is the basis for CE marking on pressure vessels and equipment. Pressure-direction-dependent fittings Valves, eg with a pressure relief hole, can usually only be operated in one flow direction. Operation opposite to the direction of flow can result in leakage in the passage. Pressure shock Incompressible media - usually liquids - (eg water) can give off a so-called pressure surge into the interior of the piping system when a valve is quickly closed due to its inertia. The pressure increases can be so high that they can cause damage to the piping and attachments. Pressure-temperature diagram The P / T diagram gives a graphical representation of the areas of application of valves. In the pressure / temperature diagram, possible combinations of pressure and temperature can be found, in which the sealing elements of the valve are not damaged and guarantee trouble-free operation of the system. Pressure-bearing housing Pressure-bearing enclosure of the valve. NOTE: Typically, it consists of the housing and, if required by design, a bonnet or cover and a combination of housing and bonnet / cover. Pressure Ratio, Critical The maximum pressure ratio of differential pressure to absolute inlet pressure, which is effective in all valve design equations for compressible media. Flow restriction, defined as in section 3.7, occurs when this maximum is reached. Flow characteristic, inherent EN 60534 1 The designation between the relative flow coefficient and the associated relative stroke h. As is independent of the drive type. Flow coefficient EN 60534 1 A coefficient that indicates the flow capacity of a control valve under fixed conditions. Flow coefficients are Av, Kv and Cv, depending on the unit system. NOTE 1: It must be remembered that the numerical values and units of the subsequently defined flow coefficients are different. However, it is possible to convert the individual coefficients. NOTE 2: The definition of the flow coefficients Av, Kv and Cv include units, designations and temperature values that are not in agreement with other parts of IEC 534. These definitions are limited to this section and are only used to show the traditional relationships in the control valve industry Dynamic sealing system In contrast to the static sealing systems, the dynamic sealing systems are also due to movement both in itself and by loaded sealing parts. Corner fitting Tap, in which the flow direction is deflected by 90 °. Anwendungsne include flow control valves in the power plant area. Degassing hole The degassing hole is located on the side of the ball on the upstream side (opposite to the pressure direction) and allows pressure equalization of the dead space in the pipeline. This degassing hole is only effective with the valve closed. Clamp housing Enclosure intended for clamping between flanges. Electrostatic discharge Friction between the medium and the inner surface of the pipe system can lead to static electricity. If the closing body, for example in a soft-sealed ball valve, insulated from the pipeline, it comes due to the static charge to a voltage gradient between the ball and the pipe. Excessive voltage gradient increases the risk of explosion. Suitable, electrically conductive seals (such as graphite packages) prevent this. Relief principle Action that is initiated when the pressure is relieved: when pressure is released, for example, the drive of a safety shut-off valve is closed. The pressure reduction takes place via a control valve. Bleed valve Auxiliary valve for bleeding a pipe system. In order to ensure efficient utilization of, for example, heat transfer between media and heat transfer units, air pockets must be removed from the pipeline system. Relieve pressure drop within a medium. Desired relaxation is a controlled and targeted pressure reduction. When pressure is reduced in actuators, the partially unintentional relaxation occurs in the form of turbulence noises. Design Review Preliminary inspection required by the Pressure Equipment Directive and hazard analysis by the manufacturer of a pressure equipment. The final design review will be carried out by the Notified Body, taking into account the hazard analysis prepared in advance by the manufacturer. Experimental method Alternative method of calculation method for valve design. The experimental method is used when the geometry of a fitting makes calculation very difficult. An example of an experimental method is the so-called initial pressure test.
back
Share by: