36results about How to "Reduce thickness fluctuation" patented technology

The invention relates to the cold tandem rolling technology. The invention solves the problem that the thickness is seriously out of tolerance caused by the traditional manual control welding line thickening method and provides a method for rolling a welding line under automatic control. The technical scheme in the method can be summarized as follows: when the welding line passes through each rack, a gap between rollers and speeds of the rollers are changed by adopting an automatic control way, thus the welding line is thickened and the tensile force of strip steel is maintained to be constant. The method provided by the invention has the beneficial effects that the strip breakage rate of the welding line is reduced and the rate of finished products is improved, and the method is applicable to a cold tandem rolling machine set.

The control method of cooling liquid for cold rolling strip steel includes: for the process computer to calculate the cooling liquid flow rate under the rated speed based on the friction and heat conductance in cold rolling; for the process computer to down send the cooling liquid flow rate during rolling; for the PLC to match based on the cooling liquid flow rate and the rolling speed and to apply the matched flow rate as the given value for controlling the valve; and for the PLC to calculate the control degree and opening of the valve, with the control degree being calculated based on the mathematical model. The present invention compensates the effect of pipeline, nozzle and other factors by means of the mathematical model to obtain the practical flow rate value and can raise the control precision of strip steel thickness.

The invention discloses an automatic tin adding device of tin plating equipment and a tin adding method. According to the automatic tin adding device, a tin block is arranged in a tin box with the bottom provided with a hollow liquid outlet, a PLC automatic control module is utilized for controlling the action of the tin box, and when tin supplementing is needed, the bottom of the tin box is vertically immersed in tin liquid, heat of a tin pond is utilized for melting the tin block, meanwhile, the melted part is gradually supplemented through gravity of the tin block, and after the tin pond iscompletely supplemented, the whole tin box is automatically lifted, the whole tin supplementing action is soft and continuous, and the liquid level of the tin pond is stable. Through the above manner, impacts on the liquid level of the tin pond during tin block adding can be reduced, generation of ripples is reduced, product tin plating layer thickness fluctuation is obviously reduced, and the product precision is obviously improved; and the tin supplementing structure is exquisite and can be embedded in the tin plating equipment, the occupied space is small, and the integral size of the tinplating equipment is reduced.

The invention discloses IF cold rolling steel with the tensile strength larger than or equal to 440 MPa. The steel comprises, by weight percent, 0.001 to 0.003% of C, 0.07 to 0.10% of Si, 0.70 to 0.90% of Mn, 0.020 to 0.045% of Als, 0.060 to 0.075% of P, not larger than 0.010% of S, 0.0005 to 0.0013% of B, not larger than 0.02% of Nb, and not larger than 0.03% of Ti. A production process comprisesthe steps of conventional smelting and casting to form a blank; rough rolling and finish rolling; segmented cooling to the coiling temperature; reeling a hot rolling plate; acid picking; cold rolling; and reeling a cold rolling plate. On the premise of ensuring the use mechanics of the steel plate, the mechanical property is small in fluctuation, the cold rolling rate is improved to not lower than 20%, the rolling speed can be stabilized to above 500 m/min, the thickness precision can be controlled to be within 15 micrometers, the strip steel rolling process is stable, the strip steel thickness is reduced, the fluctuation is stable, and the plate shape is greatly improved.

The invention discloses bamboo plywood for a structure. The bamboo plywood for the structure comprises a core board layer and hot-pressed layers arranged on the two sides of the core board layer. The core board layer is made of battens through lateral cold pressing and gluing and sanding thickness determining, wherein the battens are formed by cutting bamboo plywood GluBam which is used in a structure and has the thickness of 25 mm to 30 mm. The pressed forming surfaces of all the battens in the formed core board layer are perpendicular to pressed forming surfaces of the hot-pressed layers. According to the bamboo plywood for the structure, nails can be driven into two sides of the bamboo plywood, the thickness in each bamboo plywood layer is even, and the thickness tolerance between the plywood layers is small; in addition, the hot-pressing technology efficiency is high, and the mechanical property is high. The bamboo plywood for the structure can completely overcome the inherent defects of the existing plywood GluBam and is used for production and construction of the bamboo structure.

The invention provides a liquid high-resistance layer for a zinc oxide piezoresistor. A formula comprises Bi(NO3)3, Co(NO3)2, Mn(NO3)2 and CH3COOLi; a preparation method of the liquid high-resistancelayer comprises the following steps: mixing each raw material in the formula with a solvent; heating and dissolving. An application method of the liquid high-resistance layer coats a side face of a resistance piece with a formula solution. The liquid high-resistance layer of the zinc oxide piezoresistor has the beneficial effects that the formula of the high-resistance layer is adjusted and a technology is controlled, so that a body of the resistance piece is matched with the shrinkage rate of a glaze layer; the side face insulation problem of the resistance piece is solved; meanwhile, the square wave discharge capability of the resistance piece is improved. The original fluctuation of glaze layer thickness, caused by the fact that pre-firing shrinkage rates are different, is reduced; theresistance piece has no cracks and the technology is more stable.

The invention relates to a technological lubrication system setting method for a cold rolling single stand reversing mill. Through adjusting the flow of an emulsified liquid during a rolling process,the rolling pressure in the whole rolling process can be uniform, the whole rolling force deviation is smaller, the thickness fluctuation during the whole rolling process is reduced, and the problemsthat during an actual production process of an existing cold rolling single stand, the relatively fixed emulsified liquid flow is adopted, so that a big difference of the rolling force of each pass iscaused, and the thickness difference control fluctuation during the production process is larger are solved.

The invention relates to a preparation method of a novel liquid side surface high-resistance layer for increasing the 2ms square wave through flow of a zinc oxide piezoresistor. The method comprises the steps of mixing the prepared raw materials, heating for dissolving to prepare a uniform solution, and directly coating the side surface of a foamed resistance piece with the solution. The method ischaracterized by comprising a raw material preparation step, a ball-mill mixing step, a spray drying step, a compression formation step, a sintering step, a coating step and a piece formation step, wherein the raw material preparation step, the ball-mill mixing step, the spray drying step, the compression formation step, the sintering step and the coating step are sequentially carried out. The preparation method has the beneficial effects that by selecting a formed upper high-resistance layer, the fluctuation, caused due to non-uniform pre-sintering shrinking rate of the thickness in the past, of a glaze layer is reduced, and the process is relatively stable.

A novel inorganic side high-resistance layer preparation process for increasing the flow capacity of a zinc oxide piezoresistor. The prepared raw materials are subjected to mixing and heating for dissolution to prepare a uniform solution, the solution is molded at a resistor disc to be directly coated on the side of the resistor disc. The method comprises a raw material preparation step, a ball milling mixing step, a spray drying step, a press molding step, a sintering step, a coating step and a sheet forming step. The raw material preparation step, the ball milling mixing step, the spray drying step, the press molding step, the sintering step and the coating step are performed in order. The high-resistance layer is added after molding to reduce the fluctuation of the thickness of the glaze layer caused by the inconsistent shrinkage rate, and the process is more stable.

The invention relates to a roller press with a pre-pressing function. The roller press with the pre-pressing function comprises a main body, a rack arranged at a charging hole of the main body and a plurality of charging devices arranged on the rack, wherein a pre-pressing mechanism is further arranged on the rack; and the pre-pressing mechanism comprises a hydraulic cylinder fixed to the bottom of the rack, a driving roller transversely and rotatably fixed to a telescopic end of the hydraulic cylinder, a main fixed roller rotatably fixed to the bottom of the rack and arranged at the right side of the driving roller in parallel, a driving roller driving assembly arranged at the rear side of the rack and capable of driving the driving roller to rotate, and a main fixed roller driving assembly arranged at the rear side of the rack and capable of driving the main fixed roller to rotate. According to the invention, violent vibration generated when the roller press grinds fine powder can be effectively avoided, then the operation stability of the roller press is remarkably improved so as to increase the operation rate, the phenomenon that key components such as foundation bolts and roller shafts are broken due to the violent vibration of the roller press is effectively prevented, and therefore serious production accidents are thoroughly avoided.

The invention provides an online control method for the concentration of an emulsion of a two-time cold rolling unit and belongs to the technical field of cold rolling. The aim is to overcome fluctuation of the lubrication performance, rolling pressure and strip steel thickness and the defects of strip steel plate thickness, plate shapes and surface quality in the speed increase and decrease process of the cold rolling unit. The method comprises the steps of S1, collecting a rolling technology parameter of a strip material; S2, collecting a minimum value Cmin and a maximum value Cmax of the concentration of the emulsion of the two-time cold rolling unit; S3, collecting an outlet rolling speed v1 and setting a rolling pressure target value P; S4, calculating an elastic flattening radius Ryof a work roller; S5, calculating a friction coefficient mu of a rolling deformation area; S6, calculating an advancing slip value f of the rolling deformation area; S7, calculating the thickness ksi0of an oil film of an inlet of the rolling deformation area; S8, calculating the thickness ksi2 of an oil film separated from the surface of strip steel; S9, establishing an online control model for the concentration of the emulsion of the two-time cold rolling unit, and calculating the corresponding concentration C of the emulsion; S10, judging whether or not Cmin<=C<=Cmax is established; S11, regulating the concentration C of the emulsion in real time. The concentration of the emulsion in the rolling speed increase and decrease process is online regulated in real time.

The invention discloses a rolling control method capable of lowering the influence of watermarks of walking beams of a heating furnace on the thickness of finished products. The method is characterized by including the following steps that 1, the number of the walking beams in the heating furnace and the size of the heating furnace are detected; 2, the number of watermark points and the position of each watermark point are calculated according to the number of the walking beams and the size of the heating furnace; 3, the watermark influence coefficient of each watermark point for rolling force is calculated; and 4, actual rolling force of the watermark points is calculated according to the watermark influence coefficients. By the adoption of the technical scheme, the influence of the watermarks of the walking beams of the heating furnace on the thickness of finished moderately-thick plates can be lowered, and especially, the thickness fluctuation caused by the watermarks can still be effectively relieved under the condition of short time in the heating furnace; and the hourly output of thick plates and the thickness and accuracy of the finished products can be guaranteed, and quality losses are reduced.

In a polishing head for a CMP apparatus, a stress distributing plate made of metal or ceramic is placed between a wafer on a polishing pad and an air bag configured to press down the wafer, and a shock absorbing sheet is provided between the stress distributing plate and the underlying wafer, to thereby make pressure applied from the air bag to the wafer uniform.

The invention discloses a glass mobile phone front cover thinning agent, compared with the prior art, the produced glass mobile phone front cover (1) is provided with a hole site (2) for mounting a camera, a protective cover (6) for protecting the camera is arranged on the hole site (2), and the protective cover (6) and the hole site (2) are seamlessly and fixedly connected or integrally formed. The four corners and four edges of the glass mobile phone front cover (1) are provided with fixedly connected reinforcing ribs (3), the reinforcing ribs (3) and the glass mobile phone front cover (1) are seamlessly and fixedly connected or integrally formed, the glass mobile phone front cover (1) comprises two or more layers of plane glass (4), the plane glass (4) is provided with a protective layer (5), and the protective layer (5) is provided with a protective layer (6). The two or more layers of plane glass (4) are attached together through a bonding technology. A series of problems existing in a glass mobile phone front cover manufactured by a mobile phone shell front cover manufacturing process are solved.