SU892092A1 - Thermic valve - Google Patents

Description

(54) THERMAL VALVE

one

The invention relates to devices for shutting off pipelines, and more specifically to valves whose operation occurs under the influence of high temperature, which causes the melting of a fusible element and the shut-off of high-pressure systems, pre (Essentially gas.

Known valves, actuation | WHERE occurs when melting. fusible element.

A device is known which is a body with an inlet and an outlet channel, in the body there is a cavity filled with a low-melting alloy, the flow part is made in the form of a capillary. The thermal actuator heats the alloy, which plays the role of the locking element, when leaking into the capillary and subsequently solidifying, the flow part 13 is blocked. The disadvantage of this device is that with time the surface of the capillary walls ( even when tinning with a used low-melting alloy, it is exposed to contamination, oxidation in air or aggressive surface effects of the gas itself, which

involves the loss of wettability of the walls of the capillary by the melt and the formation of micro gaps along the walls of the capillary when the melt flows into it, which degrades the tightness of the device.

A valve is also known, comprising a housing through which a through channel passes, in the housing there is a valve seat connected to the channels, and a stop element is installed that is constantly pressed to the saddle side by means of a spring.

15

The locking element is held by a heat-sensitive retainer providing an open valve position.

As the temperature rises, the heat-sensitive element melts for 20 s, the spring pushes the valve and presses it against the saddle 2.

The disadvantage of this valve is low tightness, especially

25 when overlapping pipelines that are under the pressure of aggressive media that cause corrosion or oxidation of the saddle and the locking element, which leads to the formation of micro-cracks along the contact surface.

The purpose of the invention is to increase the reliability and tightness of the overlap of high-pressure systems with an aggressive working environment.

The goal is achieved by the fact that the temperature-sensitive element is made in the form of a filler in the internal cavity of the housing, the locking element is located inside the filler, and the input and output channels are connected by a passage channel formed in the filler. In addition, on the surfaces in contact with the temperature-sensitive element, a coating is applied from a material that ensures good wettability of the aggregate melt, for example, from a filler material.

This embodiment of the valve significantly increases its tightness, because at the time of blocking the flow channel, the temperature-sensitive element in the molten state redistributes inside the valve cavity and during cooling it almost fills the valve blocking the saddle.

The drawing shows a valve, a general view.

The valve consists of a housing 1 with a saddle 2 between the inlet 3 and the outlet 4 of the nozzle. The thermo-sensitive element 5 of a low-melting alloy fills the entire internal cavity of the valve. At the same time, a shut-off valve, a body in the form of a piston 6 and a spring-, 7 in a compressed state, is fused into the thermo-sensitive element. The input 3 and output 4 nozzles are connected through the flow-through channel 8 formed in the heat-sensitive element 5,

The material of the housing 1 | and also the piston 6 must be well wetted with a low-melting alloy. If necessary, the surface must have a suitable coating. The filling of the poloot with the melt is carried out when assembling the valve after preparing the surfaces to ensure good-jero wetting with the melt. In this case, the sub-syringe cylinder 6 immersed in the melt rests on the wire: (from a material not wetted

1 melt), which is inserted through inlet 3 and outlet 4 nozzles at the time of valve assembly. After the melt solidifies, the wire is removed, leaving the flow channel 8 through 5,

The valve operates as follows.

When the thermal actuator 9 triggers, the housing 1 is heated, the temperature sensor 5 melts, releasing the spring 7, which pushes the piston 6 to. an emphasis is placed on the end face of the saddle 2. In this case, the flow channel 8 disappears and, after solidification of the melt, the valve is in the locked state. The valve remains operable for a long time while ensuring reliable sealing.

Claims (2)

1. Thermal valve, mainly for high-pressure gas systems comprising a housing with a saddle and connecting inlet and outlet nozzles, communicated by a flow channel, a spring-loaded shut-off valve placed in the inner cavity of the housing, and a temperature-sensitive element, The 30 holding valve in the open position is distinguished by the fact that, in order to increase the reliability and tightness of the overlap of gas systems, the heat-sensitive 35, the element is designed in the form of a filler of the internal cavity of the housing, and the passage channel and the locking element are located inside the filler. 2, Thermal valve pop, 1, about tl and -that is due to the fact that on the surfaces of the body and the closure member that are in contact with the thermosensitive element, the coating is made of a material that provides wetting by the melt of the aggregate of the indicated surfaces. Sources of information taken into account in the examination 1. Instruments for scientific research, No. 7, 1964, p. 138-140. 2. US patent number 3877476, CL, 135-75, 1975.