First, the principle of automatic pressure regulating mortar permeation instrument mortar permeameter is to use the sealed container and the piping system connected to it is equal in pressure (ignoring the faucet does not count), pumping pressure, and through the electrical contact pressure gauge and simple electrical appliances System, a simple device that maintains the pressure within the specified range for testing.
When power failure, no three-phase power supply or instrument electrical control system fails, manual constant 9 pressure can be used to maintain the continuity of the test.
Second, the mortar permeation instrument is composed of a frame, a separator, a water pump, a water storage tank and an electrical system. The structure and function of each part are as follows:
1. Rack test part: The frame is welded by steel. The test mold chassis and tray are fixed on the frame with screws. The test mold and the test mold chassis are screwed together (with rubber gasket seal in the middle). Water tanks and toolboxes on the hoods on both sides of the rack, and the water tanks are used for water supply during the test.
2. Separator part: The separator is used to centrally protect the valve and a return water valve in front of the instrument, mainly to control the water cutoff of the six test pieces, and the return water valve is used for decompression.
3. Pump part: The water pump is powered by a 90-watt motor. The two-stage gear deformation drives the eccentric shaft to rotate and then drives the plunger to reciprocate through the guide post and connecting rod. The flow rate of the pump is very small. Therefore, it can be approximated that the water pressure supplied to the test piece is static, and the water pump can also be operated manually.
4. Water storage tank part: water storage tank part: The water storage tank is a container for water storage, and can also relieve the impact of pressure water. Before the test, the auxiliary funnel is used to inject water into the water storage tank through the water injection nozzle. After that, the water in the tank is drained through the waterproof nozzle.
5. Electrical control part: The working process of the electrical control part of the SS15 mortar permeation instrument is as follows:
Third, SS15 mortar permeation instrument, digital mortar permeation instrument, automatic pressure regulating mortar permeation test steps:
1. Forming of the test body: Before molding, wipe the inner wall of the mold with a cloth (do not wipe with oily things), and arrange one for all the rubber sand. . Weigh 200g of cement and 600g of sand, put it into the spherical body at the same time, stir it manually for one minute, then add water according to the standard consistency, wet mix for 3 minutes, and immediately fill the two kinds of film into the film with the water. The knife is gently inserted for 15 times. At the end, the mortar should be raised about 1 cm above the edge of the mold. Then the house vibrates on the vibrating table 30 times. When the vibration is pressed, the molding die is pressed by hand to prevent the mold from vibrating. After the vibration is completed, the molding die and the test body are cured in the air for about 30 minutes, and the excess mortar is covered with a water-stained knife. Scrape off, so that the grit is flush with the upper end of the mold, and the number is immediately placed in the maintenance box for maintenance.
2. Maintenance and demoulding of the test body: After the test body is formed, it is cured by moisture for 24±2 hours, then released from the mold and placed in the curing box for 2 days, and the temperature in the curing box should be kept at 20±3°C. The humidity should be kept above 90%.
3. Test body wax seal: The test body is formed in the moisture, and the water permeability test is carried out after three days and nights, but the test body should be taken out of the wet box one hour before the test, and the test body is enclosed in the test mold with wax. All the waxes need to be heated to completely melt, and then the circumference of the test piece is rolled in the melted wax for one week, and then immediately loaded into the test mold.
4. Penetration test: Before the test, carefully check whether the joints and joints are loose and leaking.
5. Unscrew the nut on the water injection nozzle and release all the valves to facilitate the discharge of air when filling the water. Fill the water in the water storage tank until it is full, and then seal it properly. (Please refer to the manual attached to the instrument for other methods of operation)