Glossary of engineering and industry terms

Industry Glossary

The Industry Glossary covers the most common terms and abbreviations used in the primary industry, oil and gas, petrochemical and refinery industry, transport, aviation and maritime sectors, food and pharmaceutical sectors, energy and waste recycling, machine and equipment construction, and utility and HVAC industries.

These definitions are grouped based on the eight key product groups produced and commercialized by ERIKS. To make it easier to understand these terms, we've linked them with relevant products from our webshop or articles and guides from our Knowledge center. Therefore, if you click on the term, you will be taken either to a product page that is relevant for the defined term, or to a comprehensive article that explains that product or the main category it belongs to.


2/2 solenoid valve
Solenoid valve with 2 ports. Used in process pipes.
3/2 solenoid valve
Solenoid valve with 3 ports
Three way ball valve
A ball valve with three connections.
5/2 solenoid valve
Solenoid valve with 5 ports. Used on pneumatic actuators
A medium that is abrasive or causes wear.
Absolute pressure
The pressure measured from full vacuum.
Device used for opening, controling and closing a valve, in general when a valve is positioned remotely, when located in hazardous areas. The main types of actuators are electrical, hydraulic and pneumatic actuators. These can be further classified in quarter-turn and multi-turn actuators, depending on the number of turns of the stem required for moving the valve
Anti blow-out spindle
A stem construction which prevents the stem being ejected from the ball valve body
A construction at valves to prevent the formation of sparks due to static electricity.
Air valve
Valve used for air flow control. Given that air flows are usually small, solenoid valves are commonly used for this purpose.
Angle valve
Globe valve in which the inlet and outlet ports are at 90°.
Back pressure
A constant or variable pressure at the outlet of a valve.
Construction which makes the stem seal pressureless in the open position of the valve.
Ball check valve
A check valve with a ball as a closing mechanism.
Definition of a Ball valve
Ball valve
Quarter-turn valve with a spherical closing element, used mostly as on/off valves. Ensures a quick opening and good shut-off.
Bellow sealed globe valve
Globe valve with a leak free stainless steel bellow stem seal.
If a valve closes and can be used in both directions.
Set of two different metals with different coefficients of expansion attached to each other.
Bimetallic steam trap
Steam trap that operates on subcolled condensate with a bimetallic element.
Bourdon tube
Type of construction of the sensor element for pressure gauges.
Butterfly valve
Definition of a Butterfly valve
Quarter-turn valve with a circular disk as its closing element, giving the valve a symmetrical, butterfly-like appearance. More high tech designs off-set the stem, which cams into the valve seat, this construction model being more advantageous as it causes less wear and tear on the disk and seats of the valve. High performance butterfly valves offer zero leakage, therefore can be safely used in industries like hydrocarbon processing or chemical.
Bypass valve
Small bore valve mounted in parallel to a larger, main valve, for reducing the differential pressure across the main valve before the latter is opened. Ball valves help prevent the damage of the internal components of the larger valve.
Cavity relief
A construction for a ball valve whereby excessive pressure in the space behind the ball (cavity) is relieved to the system pressure.
Definition of a Check valve
Check valve
A one direction valve to prevent backflow.
Water from condensating steam after the eveporation heat is tranferred to the product.
Condensate pump
Pump that is using steam pressure as motive.
Conduit valves
Gate valve with a rectangular disk as closing element, in which one half of the disk is solid and closes the valve, and the other has a circular port that is used for opening the valve.
Control valve
A valve construction which enables the (accurate) modulation of a medium.
Processes in which extremely low temperatures (lower than -160°C) are used.
Diaphragm valve
Definition of a Diaphragm valve
Bi-directional valve operated by applying an external force to a flexible diaphragm, made of an elastomer. These valves can be used in environments where other valve designs might clog, such as in slurries or hygienic applications.
Direct steam injection
Steam injected directly into the water to heat it.
Diverter valve
Valve which can divert the flow direction of the medium to two or more different directions.
Double acting
Working principle of an actuator in both directions with air.
Double eccentric butterfly valve
A construction for a high performance butterfly valve whereby both, the stem and the butterfly, are mounted eccentrically.
Duplex filter
Filter with two basket filtration elements for contious operation.
Electro-hydraulic operated
A valve is actuated by means of hydraulics whereby the electric hydraulic pump is locally incorporated into the control unit.
Emergency shut down valve (ESD)
Valve that uses energy stored in the actuator for closing rapidly in case of emergency.
Face to face length
The built-in length of a valve.
Fail safe
An actuator is fail safe if it regulates an operated valve in case of failure of this actuator into the desired safe position.
Filter / mud box
Strainer mounted in a pipe to protect equipment downstream.
Fire Safe
A seal construction in a ball valve or butterfly valve which, after exposure to significant heat (fire), still has a secondary metallic seal when the PTFE seal ring has been burnt.
Floating ball
Ball valve type whereby the ball is freely and flexibly placed between the sealing rings.
Floating ball steam trap
Automatic steamptrap, removes hot condensate, float principle.
Full bore
If the bore of a ball valve is equal to the connection size.
Full lift safety valve
A safety valve capable of quickly blow-off large amounts of gases, such as steam.
Definition of a Gate valve
Gate valve
Multi-turn valve with a sliding gate that moves linearly, perpendicular to the flow direction. Usually used in fully opened or fully closed position, this valve provides good sealing and is used in the petrochemical industry.
Gauge pressure
Atmospheric pressure.
Definition of a Globe valve
Globe valve
Multi-turn valve used for general flow control and throttling, that features a closing element which moves perpendicularly to the valve body seat and usually seals in a plane parallel to the flow direction.
Heat Exchanger
Crossflow heat exchanger, in plate or tube type configuration.
Hydraulic operated
Valve actuated by means of an hydraulic actuator.
Female screwed
Thread is incorporated inside the body.
Inverted bucket steam trap
Steam trap that removes hot condensate. Works on the basis of the inverted bucket float principle.
Jacketed valve
Valve whose body is covered in a jacket. Steam can be introduced into the jacket to keep the fluids at a specific temperature.
Knife gate valve
Gate valve with thin plate and a knife-like edge as closing element, used with floating solids, for example in the pulp and paper industry.
Kvs value
Reference value that indicates the maximum capacity of a fully opened valve.
Level gauge
A level indicator for visually measuring the level of a vessel.
Level transmitter
Measures a level electronically by, for instance radar, transmitting a 4 -20mA signal.
Line blind
Pipeline shut-off device that can be used instead of a valve, and which consists of a flat disk forced between two flanges. This requires more time to operate than valves but has a lower price.
Linear control valve
A control valve that provides a liniar characteristic, e.g. for level control.
The lining of a valve, for protection usually of synthetic rubber or PTFE.
Liquid damping
To dampen vibrations, the case of the thermometer or pressure gauge is filled with glycerin.
Lug type
Body construction of a butterfly valve for which the body is mounted between the connecting flanges. The body has threaded holes for the bolts.
Magnetic level gauge
Level indicator bypass tube,with a float in the medium, visualises the level using magnetism to the outside indicator.
Mechanical seal or diaphragm
Separates the medium from the measuring instrument. For instance in a pressure gauge.
Mesh indicates the number of openings per stretching inch.
Valve with additional inlet and outlet ports that allow fluids to be directed. The ball and plug valves fit in this category.
Multi-turn valve
Valve which requires multiple turns of the stem to move the valve from a fully open position to a fully closed one. Globe valves, gate and needle valves are included in this category. Multi-turn valves are also called linear valves.
Standardised connection of a pilot valve to a pneumatic actuator.
NC (normally closed)
Type of construction for (solenoid) valves closes without power.
Needle valve
Needle type globe valve for controlling flow and used on instrumentation.
NO (normally open)
Type of construction for (solenoid) valves opens without power.
Normal lift safety valve
A safety valve with moderate capacity. Often used in fluid systems.
OS&Y (Outside Screw & Yoke)
Bonnet with outside screw & yoke.
The perforation size, the round holes in the filter element.
Valve with an unobstructed bore, for instance, ball and gate valves.
Definition of a Pinch valve
Pinch valve
Valve that consists of a flexible hose pinched between two moving external elements, whcih stop the flow. It is suitable for use in slurries and in the mining industry, as its operation is not affected by solid matter in the medium.
Pilot valve
Small valve used for operating larger valves, which requires little power.
Pneumatic operated
Valve is actuated by means of compressed air power.
Plug valve
Multi-turn valve with a rotating plug as closing element. The plug may be cylindrical or truncated, and in the open position, the fluid flows through a hole in the plug.
Valve positioner accurately sets the position of the control valve.
Pressure relief valve (PRV)
A construction for a ball valve whereby excessive pressure in the ball in closed position is relieved to the system pressure.
Process controller
Electronically regulates the control of, for instance, a control valve.
PT 100
A temperature sensor with a resistance 100 Ohm resistance value that changes at changing temperatures.
Quarter turn valve
A valve that can be opened or closed with a spindle turn of 90°.
Reduced bore
Bore of a ball valve smaller than the connection size.
Reflex level gauge
The level to be measured is visualised by the refraction of the light.
Definition of a Safety valve
Safety valve
Protects a system from excessive pressure (overpressure)
Screw Down Non Return valve. Combination check valve and globe valve.
Self cleaning filter
Automatic self-cleaning filter.
Set pressure
Pressure at which a safety valve starts opening.
Single acting
Working principle of an actuator open with air / spring closing or the opposite
Single filter
Basket filter with one single basket.
Socket weld
Connection made of female sockets in de body.
Solenoid valve
Valve operated by an electrical solenoid, often deployed as pilot valves for controlling larger valves. An example is the needle globe valve.
Spring-to-close (NC)
A valve is closed by a spring when the air pressure dropped.
Spring-to-open (NO)
A valve is opened by a spring when the air pressure dropped
Static pressure
Pressure caused by, for instance, the height of a liquid colomn.
Steam trap
Discharges hot condensate and air from steam systems.
Swing check
Non-return valve with a hinged disk as closing element.
Switch boxes
Switches on a remote control valve that indicate whether the valve is fully open or completely closed.
Tank valve
Valve designed for fitting at the bottom of a tank or process vessel.
TD steam trap
Thermodynamic steam trap. Works on the basis of evaporating condensate on pressure drop.
Temporary strainer
Filter for temporary use. Used at startup in newly build installations.
Thermal expansion
Overpressure in a system caused by external heating of liquid, which may cause expansion of a liquid.
Thermostatic steam trap
Steam trap that operates based on temperature of a boiling liquid (alcohol) in a capsule.
Ability to control the amount of flow through a valve, as compared to a simple on/off function.
External heating of a product pipeline using steam or electricity.
Material of the stem, seat, disc and backseat of a valve.
Trunnion mounted ball valve
The ball is supported by trunnions into a ball valve for heavy industry applications
Union bonnet
Attachment method of the bonnet of a valve using a cap nut.
Valve body
The valve body is the main pressure boundary, which provides the ends for connecting the pipes, and the fluid flow passageway.
Valve closure member
Movable part of the valve positioned in the flow path, whose purpose is to modify the flow rate through the valve. Different types of closures include ball, disk, gate and plug.
Valve seat
Part of a valve against which the closure element effects a tight shut-off.
Valve stem
Rod extending through the bonnet assembly that permits the positioning of the closure member.
Viscosity is the magnitude of internal friction in a fluid.
V-port ball valve
V-port opening in a control ballvalve for controlling flow.
Vulcanised seat
Chemical process to make rubber elastic and flexible and to secure the lining in the butterfly valve body.
Wafer type
Body construction of a butterfly valve for which the body is mounted between the connecting flanges. Does not have any bolt holes.
Wafer type
Valve to be clamped between the connecting flanges e.g. butterfly valves, ball valves and check valves.
Water hammer (fluid systems)
This is caused when a flow of liquid in a pipeline is stopped too quickly (for instance in the case of a fast closing valve). This may result in major damage.
Water hammer (in steam systems)
Water hammer occurs when a steam valve is opened or closed to fast.
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Back-up ring
Anti-extrusion ring or support ring.
Bi-directional seal
A seal that prevents leakage from both directions.
Break-out force
The amount of frictional force required to start a body in motion over a surface.
Cold flow
Continued deformation under stress. Also called Creep.
Composite material
A heterogeneous combination of two or more materials (reinforcing elements, fillers and binders). The combination results in a material that maximizes specific performance properties.
Compression set
The permanent deformation of a seal after release of a compressive load.
A polymer consisting of two of more different monomers chemically combined.
The progressive relaxation of a given polymer while under stress.
The overlap in dimension between the seal free height and the gland into which it is installed. Synonymous: squeeze for elastomer or rubber.
Dynamic seal
A seal required to prevent leakage between opposing surfaces, which are in relative motion.
The tendency of a body to return to its original shape and dimensions after having been stretched, compressed or deformed.
Any synthetic or natural material which can return rapidly to its original shape after major or minor distortion. Elastic, rubber-like material.
Generally referred to as ultimate elongation. Percent increase in original length of a specimen when it reaches its breaking point.
Distortion or flow of part of a seal into an extrusion gap under pressure.
Extrusion gap
The clearance on the low pressure side between two bodies, which confine the seal.
Face seal
A seal that is compressed in a direction parallel to the axis.
Thin imperfections on the elastomeric portion of a seal, formed by extrusion of the elastomer at the parting lines in the mold cavity.
Flex cracking
A surface cracking induced by repeated bending or flexing.
Free height
The measure of radial height for a radial seal or the axial width for a face seal when the seal is in free-state.
A combination of corrosion and wear which occurs when a seal wipes the oxide coating from a shaft sleeve, exposing the base metal to the action of corrosion.
The force that resists the relative motion of two bodies in contact.
A seal which is used between two relatively static surfaces to prevent leakage. It is made from any deformable material.
A cavity into which a seal (or O-ring) is installed. It includes the groove and mating surface which together confines the seal.
Gland cross section
The radial height of the gland for a radial seal. The axial width of the gland for a face seal.
A material’s resistance to a distorting force. The hardness is measured by the relative resistance of the material to an indentor point. Higher numbers indicate harder material.
A rigid structure which supports and confines the seal assembly with respect to the shaft.
Hydraulic seal
A seal normally energized by a rubber or an elastomeric component and designed specifically for hydraulic and pneumatic applications.
The plastic or elastomeric member surrounding the spring.
Leakage rate
The quantity of fluid passing through a seal in a given length of time. For compressible fluids, it is normally expressed in standard cubic feet per hour (SCFH), and for uncompressible fluids, in terms of cubic centimeter per unit of time.
Lip seal
An elastomeric or fluoroplastic seal that prevents leakage in rotary shaft seal applications by employing one or more contact lips to provide a scraping or wiping action on the shaft surface. These seals are commonly called shaft seals, oil seals or rotary lip seals.
Indicative of the stiffness or rigidity of the materials. Modulus is measured in psi (pounds per square inch), and it can be measured in any mode of deformation, i.e. tension (stretching), compression (crushing), flexing (bending), or torsion (twisting).
A proprietary perfluoroelastomer material. It has excellent thermal and chemical resistance properties.
A toroidal shaped sealing device usually made from rubber or elastomeric material.
A polymeric material which is fully fluorinated and exhibits high chemical resistance.
Permanent set
Permanent deformation of spring or elastomer upon release of load.
The passage of a fluid under pressure through a solid material by diffusion.
A material formed by the joining together of many (poly) units (mer) of one or more monomers.
Quality or state of being porous.
PV factor
An arbitrary term which is the product of face pressure and relative sliding velocity. The term is normally considered to provide some measure of severity of service, and thus relates to a seal’s wear life. The units customarily used are “psi-fpm.”
Radial seal
Seals that are compressed in a radial direction. Radial seals are used as rod and piston seals and are usually dynamic, although they may occasionally be static.
Twice the distance which the center of a shaft is displaced from the axis of rotation. It is expressed in “TIR” (total indicator runout/reading).
A device employed to keep out dirt or other foreign matter.
A device designed to prevent the passage of a medium (fluid or solid).
Seal cavity
The annular area into which a seal is installed.
Spring energized seal.
A machine element capable of restoring energy and releasing it.
Static seal
A seal between two surfaces which have no relative motion.
Tensile strength
Ratio of the maximum load a material can support without fracture when being stretched to the original area of a cross section of the material.
Thermal expansion
Expansion caused by increase in temperature.
The tendency of a force to produce rotation about an axis. Frictional torque equals frictional force times the radius of rotation.
Uni-directional seal
A seal that prevents leakage from only one direction.
An enclosed space that is occupied by a gas at less than atmospheric pressure.
A thermo-setting reaction involving the use of heat and pressure, resulting in greatly increased strength and elasticity of rubber-like materials.
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The change of a material with time, under defined environmental conditions, leading to deterioration or improvement of the material properties.
Antistatic agent
Agent which is added to a molding material or is applied on a product's surface to make it less conducting.
Back taper
Reverse draft used in a mold to prevent the molded items from drawing freely.
Exudation or efflorescence on the surface of a plastic, usually caused by lubricants or plasticizers.
Projection of a plastic part designed to add strength and to facilitaet the alignment of the parts during assembly.
The opening and closing of a mold through which gases escape earely in the molding cycle.
Formation of a plastic object by pouring a fluid monomer-polymer solution into a mold.
Occurrence of a dry chalk-like deposit on the surface of a plastic.
Clamping plate
Plate fitted to a mold, used for fastening the mold to a molding machine.
Cold flow
See Creep.
Cold slug
The first material added in an injection mold.
Composite material
A heterogeneous combination of two or more materials (reinforcing elements, fillers and binders). The combination results in a material that maximizes specific performance properties.
A polymer consisting of two of more different monomers chemically combined.
Removal of excess material from the cross section of a molded part, to attain an even wall thickness.
Change of a material's dimensions with time, caused by load. When this happens at room temperature, it's called Cold flow.
Change of the physical properties of a material through a chemical reaction, such as condensation, vulcanization or polymerization. The temperature at which this change happens is called Curing temperature.
Splitting of a plastic material along the plane of its layers.
Insulating material.
A pause in the application of pressure to a mold, made just before the mold is completely closed, with the purpose of allowing gas to escape from the material.
The tendency of a body to return to its original shape and dimensions after having been stretched, compressed or deformed.
Material which stretches at room temperature, under low stress, doubling its length, and snaps back to its initial length once the stress factor is released.
Percent increase in original length of a specimen when it reaches its breaking point.
Compacting of a plastic material which is then forced through an orifice in a continuous fashion.
Family mold
Multi-cavity mold in which each of the cavities forms a different part of the assembled object.
Additive added to a resin with the purpose of improving its physical properties and reducing its price.
Extra plastic attached to a molding along the parting line.
The force that resists the relative motion of two bodies in contact.
A material’s resistance to a distorting force. The hardness is measured by the relative resistance of the material to an indentor point. Higher numbers indicate harder material.
The degree of cloudiness of a plastic material.
Injection molding
Molding procedure in which a soft plastic material is forced through a cylinder into a cavity, where it will harden in the desired shape.
Mold release
Lubricant used for coating a mold cavity, which prevents the molded item from sticking to the mold. The mold release facilitates the removal of the finished product, and is also called Release agent.
Permanent set
Increase in length of an elastic material caused by stress applied for a standard period of time and expressed as a percentage of the initial elngth, after which the material fails to return to its original length.
Material added to a plastic for increasing its workability and flexibility.
The mounting plates of a press on which the mold halves are attached.
A material formed by the joining together of many (poly) units (mer) of one or more monomers.
PV factor
A term which is the product of pressure and relative sliding velocity. The term is normally considered to provide some measure of severity of service, and thus relates to wear life.
Strong inert material bound into a plastic for improving its strength and impact resistance.
Process of holding a pressed-powder article at a temperature just below its melting point for a precise interval of time, in order for particles to fuse together, but without the mass melting.
Feed opening of an injection or transfer mold.
Tensile strength
Ratio of the maximum load a material can support without fracture when being stretched.
Thermal expansion
Expansion caused by increase in temperature.
The tendency of a force to produce rotation about an axis. Frictional torque equals frictional force times the radius of rotation.
A thermo-setting reaction involving the use of heat and pressure, resulting in greatly increased strength and elasticity of rubber-like materials.
Dimensional distortion in a plastic object after molding.
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External damage to a hose or hose assembly caused by rubbing against a coarse, rugged or sharp surface.
Abrasion resistance
The ability of the hose to withstand abrasion.
Tube (internal layer of the hose): The ability of the hose or hose assembly to withstand failure caused by an abrasive medium passing through the hose, such as sand, cement or glass.
Cover (external layer of the hose): The ability of the hose assembly to withstand abrasion caused by coarse, rugged or sharp surfaces or objects rubbing against the cover.
Adapter, adaptor
1) Threaded fittings of various sizes and materials used to change an end fitting from one type to another type or one size to another. For example, a male BSP to male NPT is often attached to a swiveling female BSP to create a male end union NPT fitting.
2) The male part of a quick coupling, for example a cam & groove coupling or cardan coupling.
Actual burst pressure
Value of the pressure at which the hose assembly is expected to rupture, or the braid is expected to fail. This pressure is determined in a laboratory setting at 21°C, with the hose installed in a straight line.
Ambient temperature
The temperature of the atmosphere or medium surrounding a hose in service.
Angular movement
The bending of the hose that causes the ends to no longer be parallel. The amount of movement is measured in degrees from the centerline of the hose.
Refers to the convolutions on a metallic hose that are a series of complete circles or rings located at right angles to the longitudinal axis of the hose.
Annular corrugated hoses
Hoses obtained by expanding the tube or inner layer of the hose from the inside to the outside. The corrugations that result are equally spaced, parallel and perpendicular to the hose axis. These hoses are superior to helical ones, from a technical point of view, as they don’t produce torsion loads with increased pressure or pressure surges, and they can be easily connected to fittings.
American National Standards Institute.
American Petroleum Institute
American Society for Testing and Materials
Axial movement
Compression or elongation along the longitudinal axis.
The portion of a fitting or coupling that is inserted into the hose, designed to seal the hose and fitting.
Bend radius
The minimum radius one can bend a hose without kinking it, damaging it, or shortening its life. The radius of a bent section of a hose is measured to the centerline (R) of the curved portion. Bend radius of a hose
Bend radius, dynamic
The smallest radius at which a hose can be used without kinking while constant or continuous flexing occurs.
Bend radius, static
The smallest radius at which a hose can be used without kinking while bent or flexed into a fixed position.
Bending force
The amount of force required to induce bending around a specified radius and hence, a measure of stiffness.
A raised area on the surface of a rubber hose. Can be caused by a separation between the rubber layers creating a medium filled space.
Blow out force
The force generated from the internal pressure attempting to push the fitting from the hose.
1) Braided reinforcement in a rubber hose to increase pressure rating and add hoop strength. A lot of different materials such as polyester, cotton or metal wire are used. A hose may have one or more braids between layers of hose material.
2) Braided reinforcement of a metal or PTFE hose a the outside of the hose to assure an increased pressure rating.
A family of copper/zinc alloys.
An alloy of copper, tin and zinc.
British Standard Pipe Parallel thread per ISO 228-1:2000
British Standard Pipe Taper thread per ISO 7-1:1994
Burst pressure
The pressure at which a rupture caused by internal pressure occurs.
Butt weld
Process in which the edges or ends of the metal sections are butted together and joined by welding.
Cam & groove
A type of fitting that allows connection and disconnection by means of arm(s) or cam(s) on the female fitting. The seal is accomplished by means of a gasket, available in various materials. These fittings are frequently used on product transfer hose assemblies.
Canadian Gas Association
Cloth impression
Impression formed on the rubber surface during vulcanization by contact with nylon curing tape.
Composite hose
Non-vulcanized hose that consists of the following construction:
An internal wire helix;
A multi-ply wall of thermoplastic layers, films and reinforcing fabrics in proportions that give the required physical properties and provide a complete seal.
A cover consisting of fabric with an abrasion resistant polymeric coating;
An external helix wire.
Conductive hose
Conductivity refers to the electrical properties of the materials making up the hose, usually the tube, layers and/or cover material. Conductivity is measured in M-Ohms. Conductive hoses are used in applications where the conveyed material can generate static electricity build-up. Such hoses will dissipate static electricity through the rubber material to the hose ends, provided the correct coupling material is used.
Corrugated hoses
Hoses made of a seamless or longitudinally-welded, thin-walled tube, into which corrugations are introduced by mechanical or hydraulic means. Each of these methods creates different corrugations: the hydraulic method leads to annular corrugated hoses, while the mechanical technique can lead to both annular or helical corrugated hoses. We see therefore that there are two main types of corrugated hoses: annular and helical.
The female part of a quick coupling. For example, a cam & groove coupling, cardan coupling. Quick release coupling.
A rubber elastomer, ASTM designation for chlorinated polyethylene.
A rubber elastomer, ASTM designation for Chloroprene Rubber
A fitting attachment method utilizing a number of dies mounted in a press. The dies close perpendicular to the hose and fitting axis, compressing the ferrule around the hose.
A rubber elastomer, ASTM designation for chlorosulfonated polyethylene.
Soft wall, wireless, built-in ends of a hose.
Deformation pressure
Pressure at which the hose corrugations will be permanently deformed.
Design pressure
The maximum pressure to which a hose will be subjected, including the momentary surges in pressure, which can occur during service.
Deutsches Institut für Normung, the German Institute for Standardization.
Two hose assemblies joined by a common elbow.
Dye penetrant test
Also called liquid penetrate inspection or penetrant testing, is a low-cost inspection method used to locate surface-breaking defects in all non-porous materials (metals, plastics or ceramics).
A document that has been adopted by one of the three recognized European Standardization Organizations: CEN, CENELEC or ETSI.
An rubber elastomer, ASTM designation for Ethylene Propylene Diene Monomer.
The wearing away of the inner corrugation of a hose caused by the conveyed media.
A co-polymer, ASTM designation for Ethylene Vinyl Acetate.
Extrusion is a process used to create objects of a fixed cross-sectional profile. A material is pushed through a die of the desired cross-section. The two main advantages of this process over other manufacturing processes are:
1. An excellent surface finish in the inside of the hose, extremely important for food, pharmaceutical, cosmetical and chemical applications
2. One "endless" tube with no possible leak-paths in comparison with hose that are produced by wrapping technology.
Fabric impression
Impression formed on the rubber surface during vulcanization by contact with nylon curing tape.
Failure of a hose caused by flexing, which results in the break down of the metal structure.
United States Food and Drug Administration.
A co-polymer, ASTM designation for Fluorinated Ethylene Propylene.
A metal cylinder placed over a hose end to affix the fitting to the hose.
Helical corrugated hoses
Helical corrugated hoses consist of a right-handed helix with constant pitch that runs along the whole length of the hose. These hoses are obtained through mechanical corrugation, during which pressure rollers are placed around the tubes and create the desired profile from the outside to the inside.
A metal wire helix embedded in the hose wall; typically used in suction hoses.
Hose braiding
Wire netting braided from bobbins that move in opposite directions. These braidings are laid directly on a metal corrugated or smooth hose or on a core, their role being to limit the expansion of the hose under internal pressure, and to maintain the structure of the tube under external pressure. Depending on the application of the hose, one or more braided layers can be used over the tube. If more layers are braided together, the resulting layer is called braided braid. This type of protective layer is used in general for hoses with a larger diameter.
Hose inlay
A hose with inlay can be made of two layers of plastic – one internal and one external, which are separated through a reinforcement or inlay made of wire. On the other hand, a hose without inlay is made of two plastic layers that have no additional material between them.
Hydrostatic testing
The use of a pressurized liquid, usually water, to test a hose assembly for leakage and hose change-in-length.
International Organization for Standardization.
Joint Industrial Council (no longer in existence). An engineering group that established an industry standard fitting design incorporating a 37° mating surface, male and female styles. Now governed by SAE.
Lateral movement
This movement occurs when the hose centerline is moved in a plane perpendicular to the longitudinal axis with the end remaining parallel. Lateral movement of a hose
Layflat hoses
Flexible hoses made of two layers of PVC that are inseparably fused, with a woven yarn reinforcement. Unlike rubber or metal hoses, these ones are collapsible, and are very flexible, lightweight, strong and weather resistant.
A round section used for size and to support hose during fabrication and vulcanization. It may be rigid (carbon steel or stainless steel) or flexible (rubber or plastic).
Mandrel built
A hose fabricated on a mandrel.
Media, medium
The substance being conveyed through a hose.
Maximum working pressure
Maximum operating pressure at which the hose assembly should be subjected. This value should take into consideration the surges in pressure that may occur during service.
A rubber elastomer, ASTM designation for Nitrile Butadiene Rubber.
National Pipe Taper. Pipe thread per ANSI B1.20.1.
National Pipe Tapered for Fuels. Identical as NPT except dry-seal per ANSI B1.20.3.
Ozone cracking
Surface cracks caused by exposure to an atmosphere containing ozone.
Ozone resistance
The ability to withstand the deteriorating effects of ozone.
Offset motion
Motion that occurs when the ends of a hose assembly are displaced laterally to each other, in a place perpendicular to the longitudinal axis of the hose.
A mechanical projectile used for cleaning hose.
Pin pricked
Perforations through the cover of a hose to vent permeating gases.
A material applied to metal by electroplating, for the purpose of reducing corrosion; typically a more noble metal such a zinc is applied to steel.
An individual layer in hose construction.
Polyurethane (PUR or PU)
Is a polymer composed of organic units joined by carbamate (urethane) links. Polyurethane hoses have a very good abrasion resistance.
Pressure drop
The amount of pressure lost by a medium as it is conveyed through a hose assembly.
Proof pressure
See Test pressure
Pounds per square inch.
Synthetic fluoropolymer of tetrafluoroethylene that has numerous applications. PTFE is renowned as the most chemically resistant material known. PTFE lined hoses can be used for a wider variety of chemicals than any other hose type, making it the ideal choice for very corrosive chemical applications and multiproduct applications.
ASTM designation for polyvinyl chloride.
Radial motion
Motion that occurs when the centerline of a hose assembly is bent in a circular arc.
Rated burst pressure
Value of the burst pressure which may be a percentage of the actual burst pressure measured in a laboratory setting.
Society of Automotive Engineers.
An rubber elastomer, ASTM designation for Styrene-Butadiene.
That portion of a fitting, which is inserted into the bore of a hose.
Shock pressure
Pressure spike; sudden increase in pressure which creates a shock wave through the hose assembly. Also called Surge pressure.
The removal of a short length of cover and/or tube to permit the attachment of a fitting directly over the hose reinforcement.
Spring guard
A helically wound component applied internally or externally to a hose assembly, used for strain relief and collapse resistance.
Static electricity
Static electricity is the electric charge generated when there is a friction between two things made of different materials or substances.
Static wire
A copper wire incorporated in a hose to conduct static electricity.
Failure of a hose caused by excessive internal pressure, which causes the internal corrugations to warp into an S or U shape.
Test pressure
Maximum pressure at which a hose can be subjected to without deforming its corrugations and without exceeding 50% of the burst pressure. Also called Proof pressure.
Tig weld
The gas tungsten arc welding process sometimes referred to a shielded arc.
Thermoplastic elastomer, also commonly referred to a thermoplastic rubber (TPR). A class of materials that demonstrate both plastic and elastomeric properties than can be extruded and injection molded.
Thermoplastic rubber.
Traveling loops
Installation configuration designed for axial motion or excessive offset motion.
United States Pharmacopia.
United States Department of Agriculture.
Working pressure
The maximum pressure to which a hose will be subjected, including the momentary surges in pressure, which can occur during service.
Working temperature
The temperature range of the application, may include the temperature of the fluid conveyed or the environmental conditions the assembly is exposed to in use.
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Anti-extrusion ring
Ring used to fit behind rubber o-ring seals, to prevent extrusion into the gap between the metal pieces. Also called Back-up ring.
Automatic U-joint
An U-shaped sealing ring made of a strong pliable plastic or rubber material.
Baffle ring
Ring used for slowing down the flow of fluids along a shaft
Corrugated rubber or plastic piece which can stretch with a shaft, to keep the shaft clean.
Inner dimension (I.D.) of a gasket.
Rubber or plastic part used for preventing metal-to-metal contact.
Surface effect in rubber materials characterized by many minute cracks.
Creep relaxation
Loss of stress accompanied by the decreasing of the compressed thickness.
Double acting seal
A seal ring used for sealing in two directions, on the push and the pull stroke of a cylinder.
Dust seal
A seal used for excluding dust from a machine or device.
Face seal
Rubber ring used like a gasket between two flat piece of metal.
Full faced gasket
Gasket that covers the full face of a flange and features bolt holes.
Rubber-like part made of a flexible material that fits between two metal parts, for sealing purposes. It is usually a flat, non-moving part made from a homogeneous rubber, a fabric-reinforced rubber or other materials.
Loop of elastomer with an o-shaped cross-section.
Ozone cracking
Cracking of the surface caused by exposure to ozone.
Pressure rating
The pressure the material can seal against.
Premature vulcanization of a rubber compound due to excessive exposure to heat.
Spiral wound gasket (S.W.G.)
Gaskets made of metal coil or winding, with a material filler. Spiral wounds can withstand very high perssures.
Irreversible change in the chemical structure of a rubber compound, which becomes less plastic and more resistant to swelling by organic liquids. The elastic properties are improved or extended over a greater range of temperature.
X ring
Rubber ring with a special shape used for replacing O-rings, and for eliminating the potential rolling of the ring.
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Anti-friction bearing
Bearing that uses rolling contact to cut power loss resulting from friction.
Ball bearing
Definition of a Ball bearing
A ball bearing is a rolling bearing and usually consists of an inner and outer ring. One or two rows of balls sit in between these rings. A ball bearing ensures that the friction of a rotational movement is reduced due to the rotation of the balls. Ball bearings have a simple design, they are suitable for high and even very high speeds, they are robust and require little maintenance.
Designed to enable rotational or linear movement in a device, bearings are machine elements that are used to reduce friction between moving parts and to enhance the speed and efficiency of a system. At the same time, bearings are used to support other parts of a machine by handling various amounts of stress. Depending on the design of the bearing, these surfaces may vary, but in general bearings are made of two rings or discs with raceways, rolling elements like rollers or balls that roll against the inner and outer metal surfaces, and a cage which keeps the rollers apart and guides them.
Definition of a Bearing
Separator that holds the rolling elements in their position along the races.
Definition of a Roller bearing
Roller bearing
Roller bearings generally consist of two bearing rings with integrated races. Between the bearing rings there are rolling elements. These elements are also referred to as anti-friction bodies and move freely over the races.
Slide bearing
In slide bearings, the part moves along the sliding surface of a fixed bearing bush, bearing block or sliding strip. As a result, there is a sliding movement directly between the sliding layer of the bearing element and the part mounted on the bearing.
Definition of a Spherical bearing
Spherical bearing
Spherical bearings are self-aligning bearings. This prevents misalignment of the shaft and ensures that the shaft does not need to be adjusted. Spherical bearings are also less sensitive to deflection or bending of the shaft.
Tapered bearing
Definition of a Tapered bearing
Tapered bearings have inner and outer ring races between the rollers. The projection lines of the surfaces hit each other at the same point on the shaft. This design makes it possible to absorb radial and axial loads simultaneously.
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Finger guard
Item used for protecting the fingers. Finger guards are generally available in three different styles: as a flat guard with elastic back and open end, as guard with closed end, and as a wrap with elastic back and open end which provides protection around the entire circumference of the finger.
Protective glove used in certain industries like constructions, plumbing, cutting, working with metals, auto repair and equipment repair, stamping. They are usually made of metal, rubber, leather or a combination of these materials, and provide protection against cuts, hits, punches, abrasion and temperature.
Glove without individual finger openings, that has a high thermal efficiency. Some mittens have a flap that allows one to uncover their fingers during tasks that require a better grip or higher precision.
Protective glove
Garment used for protecting the hands and wrists from hazards in the workplace. They are suitable for virtually all industries and applications, but their functionality is influenced by the design, construction and materials they are made of. Gloves offer protection against punctures and cuts, chemicals, heat and cold, electricity, contaminants.
Safety cuff
Personal protection item that can be attached by a seam at the wrist for extending the hand and arm protection. Generally made of more rigid materials that remain firm even when exposed to perspiration, and slide on and off easily.
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Apron feeder
A series of overlapping metal plates mounted on a rotating chain, used for transporting heavy or abrasive materials.
Braking device used for preventing a loaded, inclined conveyor belt from rolling backwards in case the motor stops.
Ball Table
A combination of BTA ball transfer units fitted into a welded plate within a framework to enable products to be easily manoeuvred (spun) in multiple directions.
The part of a conveyor upon which the load rests or slides while conveyed.
A flexible band placed around two or more pulleys for the purpose of transmitting motion, power or materials from one point to another.
Brake Motor
A device usually mounted on a motor Shaft between motor and reducer designed to engage automatically when the electric current is cut off or fails.
Wheels mounted within a support structure to enable conveyors to become portable.
Centre Drive
A drive assembly mounted underneath a standard reversible or inter-floor belt conveyor, usually supplied complete with Brake motor.
Chain Drive
A power transmission device employing a drive chain and sprockets.
Chain Guard
A covering or protection for drive or conveyor chains for safety purposes.
Change of Direction Unit
A driven length of belt conveyor, used to move product horizontally onto an incline/decline conveyor. Also known as a Powered Feeder unit.
Enclosure used for containing material as it is transferred from one piece of equipment to another.
Attachment fitted to a conveyor belt for forming a raised section that supports and stabilizes the products carried up an incline belt.
Conveyor belt
Belt used in the internal transport of goods, for example to move a semi-finished product or a finished product to a different location within the production process.
Conveyor Rollers
Non-powered rolling component used for supporting a conveyor belt
Decline Conveyor
A conveyor used for transporting products down a slope.
Degree of Incline
Angle of slope in degrees that a conveyor is installed.
Discharge End
Location at which objects are removed from the conveyor.
Drive Unit
An assembly of the necessary structural, mechanical and electrical parts which provide the motive power for the conveyor.
Drive Pulley
A Pulley mounted on the drive shaft that transmits power to the belt with which it is in contact.
Device on the infeed of the conveyor that regulates the flow of products from a storage hopper onto the belt.
Floor Supports
Adjustable supporting members with vertical adjustments for levelling the conveyor.
A section of conveyor equipped with a hinge mechanism to provide an opening for a walkway etc. Available in both powered roller conveyor and Gravity roller conveyor.
Gravity Rollers
Rollers fitted into Gravity conveyor framework.
Guard Rail
Channel members mounted on the top flange of the conveyor used to guide products
Non-powered rolling component used for supporting a conveyor belt on the carrying or return run.
Infeed end
The end of a conveyor belt where parts are fed on.
Limit Switch
Electrical device used to sense product location.
Motorised Roller
A roller fitted with its own internal motor used for zero line pressure applications.
Nip guard
Plate placed in various points of the conveyor belt to eliminate danger.
A section of conveyor to provide transition from incline to horizontal or horizontal to incline.
Photo Electric Cell
Electrical device used to sense product location.
Powered feeder
A driven length of belt conveyor, used to move product horizontally onto an incline/decline conveyor. Also known as a change of direction unit.
A wheel, usually cylindrical, but polygonal in cross section with its centre bored for mounting on a shaft.
Return Idler
A roller which supports the return run of the belt.
A round part free to revolve about its outer surface. The face may be straight, tapered or crowned. Rollers may also serve as the rolling support for the load being conveyed.
Roller Bed
A series of rollers used to support a conveying system.
Rigid plastic or brush used for cleaning the belt.
Side Channels
Members which support the slider bed or rollers on the side of the conveyor.
Side Mounted Drive Unit
A geared motor mounted to the drive pulley and situated on the side of the conveyor.
Snub Roller
Any rollers used to increase the arc of contact between a belt and drive pulley.
Support Stand
Arrangement of members used to maintain the elevation or alignment of the conveyors. Supports can take the form of hangers, floor supports or brackets.
The assembly of the structural and mechanical parts which provide the means to adjust the length of the belt or chain to compensate for belt stretch, shrinkage or wear and to maintain correct tension.
Tapered Roller Bend
A curved section of roller conveyor fitted with tapered rollers.
Terminal Roller
A pulley mounted at the tail end of a conveyor, its purpose is to return the belt.
Under guard
Either plastic or sheet metal used to cover the underside of a conveyor section.
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