Precast concrete filter plate
Product Introduction
The cement filter plate made by our company is poured with flat steel mold. The filter plate is a reinforced concrete filter plate made of acid resistant, corrosion resistant and pressure resistant reinforced concrete. The cement grade is 425 # ordinary Portland cement, with compressive strength>42.5Mpa, tensile strength>6.4.Mpa, initial setting time greater than 20 minutes, and final setting time less than 10 hours. The nominal particle size of gravels is 5-25mm, the needle shape content is ≤ 15%, the mud content is ≤ 1%, and the sand is natural quartz sand. The filter plate is made by strictly implementing the relevant national standards, calculating the opening ratio according to the design requirements, embedding ABS engineering plastic embedded casing, equipped with double-layer two-way high-quality rebar, high-grade cement, standard fine stone and quartz sand, mechanically mixing, tamping and pouring.
The above materials are free of harmful substances, and the concrete grading meets the C28 grading requirements. The reinforcement shall be grade II deformed steel bars with a diameter of 8-12mm and double row reinforcement framework. The surface shall be flat, without exposed reinforcement, warpage, vibration crack, damage on all sides, accurate embedded casing, no inversion, deflection, omission, and no blockage in the casing. The horizontal error of the upper and lower sides of the filter plate is ± 1mm per square meter. The installation in the filter tank shall reach the high precision of the whole tank error ≤ 5mm, and the four sides of the filter plate shall be neat without warping, which fully meets the requirements of the filter tank design technical specifications.
The horizontal or vertical steel mold is used to make the filter plate to ensure the accuracy requirements.
Tensile strength of filter plate ≥ 280Mpa.
Compressive strength of filter plate ≥ 280Mpa.
Impact strength of filter plate ≥ 280Mpa.
The limit tolerance of filter plate flatness is ± 1.5mm
The center deviation of filter head sealing ring or sleeve is within ± 1.5mm.
Technical indexes of filter plate:
Concrete strength: C25 ～ C30
Reinforcement: double-layer two-way φ 10 National standard deformed steel bar
Production process conditions and requirements: according to GB50204 standard.
Appearance: the surface is flat, without exposed reinforcement, warping, vibration cracking, no damage on four sides, the embedded casing is accurate without inversion, deflection and omission, and there is no blockage in the casing.
Tolerance: flatness error of both sides ± 1mm
Perpendicularity error of four sides ≤ 5mm
Installation Requirements
The horizontal installation accuracy of the filter plate is required to be high. Its important basis is the leveling of the whole tank of the filter beam and the positioning accuracy of the stainless steel parts used to embed the riveted filter plate. Therefore, the leveling of the filter beam requires a horizontal line, which must be equipped with a high standard metal mold and skilled manufacturing technology to ensure the flatness of the filter beam. After the plane is leveled, the filter plate can be installed.
1. The construction shall be carried out according to the requirements of the design drawings. The horizontal error of a single tank surface shall be greater than ± 2mm, and the elevation error of each grid filter shall not be greater than ± 5mm;
2. The joint of filter plate shall be air tight and water tight, and can withstand the pressure of flushing;
3. Before the filter plate is laid, the error of the elevation value of the bearing beam surface detected with a level gauge is less than ± 2mm;
4. 903 polymer cement mortar shall be used for caulking and filling the filter plate joints. The caulking shall be cured in a humid environment for three days and put into use after seven days;
5. During construction, it shall be noted that the mortar shall not leak into the pool or seal the filter head. After installation, the mortar on the filter plate surface shall be cleaned.
[Installation inspection]
Use a level gauge to check the level, and add water discharge to check the tightness of the plug. The success or failure of filter plate fabrication and installation is directly related to the success or failure of air-water backwashing process. Because compared with the traditional single water flushing process, the air-water backwashing process adds air backwashing, which requires that the horizontal error of the filter plate surface of a single tank should not be greater than ± 2mm, and the elevation error of each grid filter should not be greater than ± 5mm. Only in this way can uneven backwashing not cause sludge agglomeration, which affects the water quality and treatment effect.
[Advantages]
The filter plate is a key device in the water treatment process, which plays a dual role in the filter tank to carry the filtering of the filter material layer and back flushing water (gas) distribution. The quality of the filter plate (especially the flatness and precision of the filter plate) is directly related to the filtered water quality, water volume and long-term operation benefits of water plants and sewage plants. The traditional water distribution system of the filter tank has large resistance in filtering and backwashing, uneven water distribution, many dead water areas, and the filter material is easy to harden and accumulate mud. At the same time, due to the local flushing intensity, the supporting layer is loose, and sand leakage and other adverse consequences occur.
