RU77672U1 - AUTOMATIC TEST INSTALLATION FOR FROST RESISTANCE TESTS - Google Patents

Abstract

The test installation belongs to the field of control and testing equipment used for frost resistance tests of ceramic, concrete and mortar samples and is intended for testing by the basic method in accordance with GOST 10060.1-95 in automatic mode. This technical result is achieved by the fact that in an automatic test installation, made in one block and consisting of a thermally insulated body in which a working chamber with a container for placing test samples is located, machine division with a refrigerating machine and a control unit with a programmable microprocessor, two devices are combined in one unit - a freezing device and a defrosting device, which function and interact automatically in accordance with a given test program in accordance with GOST 10060.2-95.

Description

This utility model relates to the field of test equipment used for frost resistance tests of ceramic, concrete and mortar samples. Designed for testing the frost resistance of concrete samples by the basic method according to GOST 10060.1-95 “Concretes. The basic method for determining frost resistance. "

The KHTB-0.5-155 freezers manufactured by the Volgograd Mechanical Plant, the KTK-3000, KTK-800, TV 1000, TBV2000 freezers manufactured by the ILKA association, Germany are widely known (see GOST 7025-91 “Brick and Stones” ceramic and silicate ”, p.13). These freezers are designed to conduct frost tests of cement, concrete, mortar samples and can be used to conduct frost tests of concrete samples using the basic method according to GOST 10060.1-95, above.

However, the design and principle of operation of the known freezers provides for their use in a cycle of tests for frost resistance only for the operation of freezing samples. For the subsequent thawing operation, the samples must be unloaded from the freezer into a water bath equipped with a device to maintain the water temperature.

After completion of the thawing operation, the samples are again loaded into the freezer and the test cycle is repeated again. So, for example, to confirm the concrete grade for F100 frost resistance, the basic method according to GOST 10060.0-95 will require 100 freeze-thaw cycles. With single-shift operation, such tests are carried out in 100 days. Such long periods of testing do not allow you to quickly and timely adjust the composition of concrete mixtures, and high complexity increases the cost of testing.

The closest known source of information is “Chamber of cold and heat 12 KHT - 0,063-016”, manufactured by OJSC “VOLGOGRADELECTRONMASH”, Volgograd (see www.volgelmash.ru, photocopy is attached). The known camera is made in one block and consists of a thermally insulated body. In the middle part of the case there is a working chamber with a stainless steel container for placing samples. In the lower part of the casing there is a machine room with a cascade refrigeration machine, and in the upper part of the casing above the working chamber there is a control unit based on the microprocessor unit of the temperature controller-meter.

However, the design of the known camera provides for its use in the cycle of testing for frost resistance by the basic method according to GOST 10060.1-95 only for the operation of freezing samples. For the subsequent thawing operation, the samples must be unloaded from the freezer to a bath with water, equipped with a device to maintain the water temperature within the specified limits. After completion of the thawing operation, the samples are again loaded into the freezer, and the test cycle is repeated again.

The problem to which the claimed utility model is directed is to reduce the complexity and duration of the frost test.

The technical result obtained in the implementation of the utility model is the automation of the test mode without the operation of unloading samples from the freezer for defrosting. This is achieved by the fact that in the known design of the freezer, made in one unit, consisting of a thermally insulated body, in which there is a working chamber with a container for placing test samples, an engine room with a refrigerating machine and a control unit with a microprocessor, two devices are combined in one unit - device for freezing and device for thawing, functioning and interacting automatically in accordance with a given test program in accordance with GOST 10060.2-95.

The essence of the claimed utility model is illustrated in the drawing, where figure 1 is a General view.

The test installation consists of a heat-insulated casing 1 with a door 2. In the upper part of the casing there is an engine room 3 with a refrigerating machine. In the lower part of the housing there is a circulation pump 4 and a tank 5 for water or stainless steel brine. In the middle part of the housing there is a working chamber 6 with a stainless steel container for placing samples. In the upper part of the housing is a control unit 7 with a microprocessor meter-temperature controller. The temperature sensor 8 is fixed in the working chamber.

The operation of the automatic test setup is as follows. Samples for testing for frost resistance, located in the container of the working chamber 6 undergo a freezing cycle in accordance with a given test program. After the completion of the freezing cycle, water is supplied from the container 5 to the container with the samples using the circulation pump 4 and the defrost cycle begins. To maintain the temperature of the circulating water within the specified limits, in the tank with water 5, if necessary, the heater is switched on. After the end of the defrost cycle, the circulation pump 4 is turned off, the water is drained by gravity into the tank 5, the chiller is turned on and the freezing cycle begins, and so on, cycle by cycle in automatic mode. The number of freezing and defrost cycles is set by the program. If the number of required cycles exceeds 100 units, then the test process is suspended to replace the circulating water in accordance with clause 6.7 of GOST 10060.1-95. after replacing the water, the process continues.

The round-the-clock continuous operation of the automatic test setup significantly reduces the complexity of the full test cycle and the total test time. To confirm the brand for frost resistance F100 with the basic method, it will take 30-35 days to work in automatic mode, i.e. three times less time compared to working with a separate bath for thawing and unloading-loading samples into the freezer after each defrosting cycle.

Claims (1)

Automatic installation for testing for frost resistance, consisting of a thermally insulated body with a door, in the upper part of which there is a machine room with a refrigerating machine and a control unit with a microprocessor meter - temperature regulator, in the lower part - a circulation pump and a stainless steel tank for water or brine, in the middle part - a working chamber with a temperature sensor and a stainless steel container for placing samples.