This catalogue contains technical data and notes over valves to the regulation and shut-off position of liquids, fixed substances, gases and steams. We met in this catalogue only one selection, can you however at any time a complete documentation over certain valves and measuring instruments send.

A valve can operate satisfyingly only if it were selected on its intended purpose. Please you address us with technical further inquiries, because we want in a close contact with you, in order to ensure a satisfying function of the valves. We give you security that the selected type is really the best and most rational for the respective intended purpose.  

We hope that this catalogue will carry good services for you out and to take suggestions on the possible improvement of future outputs gladly against.

Definitions for valves

Stop valve  

A stop valve, in which the locking off section is taken off by means of a spindle from the seat or put on these, whereby the spindle axle is located in a right angle on one level, which is formed by the seat.

With the spindle thread on the inside the thread from the other side is situated to the stem guide within the upper section of the housing, with the external spindle thread is the thread from the other side in the wall of the upper section.

Through-way valves normally consist of a symmetrical body with each other opposite links. The spindle axle forms a right angle with an axle put by both links. With oblique-seated valves this angle amounts to approx. 45°. With angle valves the links are to each other in a right angle.

Operation of the stop valves takes place via a screw mechanism with groove by means of handwheel or drive (electrically, pneumatically, hydraulically)

Recoil valves

An valve, which the return flow by a setback mechanism prevents. The passage is opened effected via the current, reasoning with a back-up by the weight of the mechanism or via a current reversal.  

To preventing the return flow is used with a check valve around an axle tiltable hung up flap.

With a check valve the setback mechanism is formed by a spring-tensioned plate, piston or a ball present at an axle.

A foot valve is at lower suction tube end and is often equipped with a filter. The check valve is usually used in pipings, in which by pumps or gravitation moved media flow.

With return flow preventing a diaphragm which is situated on a guidance body is opened or the return flow is prevented. The selection of the suitable model or the correct size depends on a number of parameters, like operating pressure, operating temperature, rate, admissible friction loss etc.. Check valves are normally used in smaller pipings with diameters to DN 100 and even for higher pressures.  

Slidegate valve

A shutoff device that permits the free flow of a current. The links are situated themselves opposite in an axle, which locking off section (wedge or disk) moved between the seat faces by a spindle, whose axle is situated in a right angle for flow direction. Slidegate valve gives it in the remarks spindle thread on the inside and external.

With the emergency shut-down slidegate valve, designed for fast opening and reasoning, the locking off section is moved by lever force by means of a hand lever.

A wedge-type slide valve is a shutoff device, with which reasoning takes place via wedge effect between locking off section and the seats. The wedge consists of a not flexible material or however with a core of inelastic material.

With the parallel slide valve the locking off section consists two disks of or. These disks slide between parallel seats, a close termination with the pressure of the flowing medium are obtained, which firmly presses the disk which is situated in the diverting direction against your seat. Slidegate valves are not suitable for throttle functions; they should be quite closed either completely up or. The one-piece shut-off wedge is substantial executed, can in operation neither swing nor rattle, so that the wear is small.  

Safety valve

An valve, which delivers a part of the flowable medium in it automatically outward, in order to avoid the exceeding of a determined maximum printing. It is used generally for all media, which make a fast relieving of positive pressure necessary. In the usual execution the shutting is loaded by directly a feather/spring sitting on it.

The regulations valid after AD specifications require the fact that relief valves are to be attached at all receivers so that is guaranteed that your highest design pressure cannot be exceeded. With the full stroke safety valve the stroke is supported with the escaping pressure. They are fixed adjusted to a adjustable  positive pressure.

Overflow valve

Valves, which discharge a part of the flowing material automatically, in order to let no positive pressure develop. It is used generally for not compressable materials (liquids such as water, oil, etc.). Direct full discharge is not necessary, since already a small discharge lowers the printing. With directly working overflow valves the locking off section opens automatically by the direct load on the locking off section over a feather/spring. Auxiliary controlled overflow valves have max. flowing through power with full passage, require however when closing or opening an additional control or control valve. Overflow valves are adjustable. Overflow valves keep the printing before the valve constant.

Pressure-reducing valve

Pressure-reducing valves cause the reduction of a higher form to a constant rear printing. If no auxiliary energy is needed, then a pressure-reducing valve is called direct working. Pressure-reducing valves keep the printing behind the valve constant.

Ball valve

Shutoff device with one perforate ball. By turn of the ball the current can become released or closed. Ball valves are in such a way designed, which is as small as possible the friction with the rotation of the ball and an optimal sealing is ensured in the passage and in the stem guide. The ball to DN 80 mostly is swimming stored. With a quarter-turn the ball valve is closed or opened. During full passage the current almost takes place via the cock without resistance. Under normal conditions the ball valve is not to be used as throttle valve.

Butterfly valve

A shutoff device, whose mobile section consists of a disk, which is swivelling in axially arranged bearings. Metallically or soft seals can be both in the housing and on the locking off flap put or let in. Butterfly valves to be able can be used both for a close termination as well as for gradual throttling (butterfly valves) or for a combination of these purposes.

Diaphragm valve

A stop valve, whose locking off section consists either of a ductile diaphragm or is enclosed by it. The diaphragm causes the termination and serves at the same time as seal between the operating mechanism and the flowing through medium. The diaphragm locks thereby the mechanism of the upper section against the liquid. Housings and diaphragms are available in a very large area of most diverse materials.  


Franz Joost & Co.
Am Jaegerberg 9
16727 Velten - GERMANY
Tel. +49-3304-388-118
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