Apparatus for measuring foam wet weight gain for low temperature insulation

Abstract

The invention discloses a hygroscopic weight increment measuring device for low-temperature and heat-insulating foam plastic. A constant-temperature high-humidity box, a sample sleeve, a liquid nitrogen trough, an external liquid nitrogen tank and an internal liquid nitrogen tank are connected in sequence; a flow guiding cover is sleeved outside the sample sleeve; a groove is arranged at the upper end of the constant-temperature high-humidity box; a G-10 washer is arranged in the groove; the inner wall of the constant-temperature high-humidity box is provided with a PTC (positive temperature coefficient) heating resistor and a fan; a water inlet system and a water discharging pipeline are arranged at the lower part of the constant-temperature high-humidity box; an ultrasonic generator anda miniature lifter is arranged at the bottom of the constant-temperature high-humidity box; a sample is mounted in the sample sleeve; a liquid nitrogen inlet pipe, a safety valve and an outlet shutoff valve are arranged at the top of the external liquid nitrogen tank; the liquid nitrogen inlet pipe is provided with a manual shutoff valve; the external liquid nitrogen tank and the internal liquid nitrogen tank are connected with the liquid nitrogen trough; a copper disc is welded at the bottom of the liquid nitrogen trough; the lower part of the external liquid nitrogen tank is provided with avacuumizing opening; and the outlet shutoff valve is connected with the flow guiding cover through a pipeline. By using the measuring device, the hygroscopic weight increment measurement of the sample is achieved in a high-humidity extreme environment with one side at a super-low temperature and the other side at a room temperature, and furthermore, the sample can be conveniently moved away and mounted.

Description

technical field [0001] The invention relates to the technical field of aerospace and refrigeration low-temperature engineering, in particular to a device for measuring moisture absorption and weight gain of foamed plastics for low-temperature heat insulation. Background technique [0002] Solid polyurethane foam has the characteristics of light weight, mechanical strength and good thermal insulation performance. It has become the standard thermal insulation material for low-temperature fuel storage tanks in space vehicles. 180°C) outside of the storage tank. The required thrust of the rocket depends on the rocket load. In order to accurately calculate and control the rocket thrust and the required fuel, the payload and size of the rocket are required to be small and accurate. Although the foam insulation material has a lower density, it occupies a large area on the rocket. Before the rocket is launched, the foam material is exposed to low temperature (tank wall) and high h...

AI Technical Summary

Problems solved by technology

[0005] None of the above-mentioned patent application descriptions involves a test device for moisture absorption and weight gain of foamed plastics for low-temperature heat insulation

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