221results about How to "Improve rolling stability" patented technology

The invention discloses a trajectory tracking control method used for a driverless vehicle. The method includes the following steps that the current position point of a vehicle body is confirmed according to a reference trajectory; a matching point nearest to the current position point of the vehicle is found, and the road curvature of the nearest matching point is obtained according to a two-point curvature obtaining method; according to the current position point of the vehicle and the nearest matching point, a trajectory tracking error is obtained through calculation and comprises a transverse error and a head pointing error; a dynamic model feeding back cornering force on the basis of front wheels is established, and the optimal feedback control rate is obtained by the adoption of an LQR control algorithm; and the cornering force of the front wheels is determined, a front wheel slip angle is obtained on the basis of a reverse tire model, and then the steering wheel angle controlledquantity is obtained and issued to a steering-by-wire system to achieve trajectory tracking control. By the adoption of the method, the stability of trajectory tracking control of the driverless vehicle is improved, the trajectory tracking accuracy is improved, the tire slip angle is restrained, and the possibility that the tire force of the vehicle is saturated under an extreme working conditionand therefore the vehicle loses stability is avoided.

The invention discloses a steckel mill rolled piece head-and-tail deviation control method which comprises the following steps that: based on existing equipment configuration, different modes are distinguished by integrating the rolling information of a steckel mill according to the rolled piece deviation and rough rolling force in the final step of rough rolling, then the deviation controlled by roll gaps on both sides of the steckel mill is determined, and roll gap setting control for preventing deviation is carried out. Through the method, the hand-and-tail deviation of strip steel can be reduced, shut-down accidents caused by the deviation of strip steel can be prevented, and the rolling stability of the steckel mill can be improved.

The invention is a method of erecting all-cantilever erected steel truss beams assisted by diagonal ropes, as well as a relevant system. The method utilizes a bearer cable tower combined with a steel structure center tower column with diagonal ropes; install a tower-type crane on the top face of the steel truss beam end at the first hole with an overhead bridge crane in a ground craning station; anchor cases below the front and rear diagonal ropes are connected with side plates at steel beam nodes, and after that, directly lift the tower to apply pre-tension on the diagonal ropes; perform all-cantilever erection for the front steel truss beam. After finishing erection of the orifice steel beam, complet load removal from the diagonal ropes with a method of pushing up the temporary seat for the front pier and lowering back a pushing and craning device between upper and lower seats of the bearer cable tower. The system comprises an auxiliary tower truss, a tower center vertical column, the upper and lower support seats, the front and rear diagonal ropes, the upper and lower anchor cases for diagonal ropes, a tower top anchor beam and a walking mechanism. The invention has the following advantages: For large-span continuous steel truss beams, utilize a special device additionally to erect multi-span steel truss beams, so as to reduce internal stress in installation of steel truss beam members, lower end deflection of the front extension arm, and increase the inclination stability of a steel truss beam on the extension arm. Meanwhile, the invention can low investment and short construction period and provide very convenient operation.

The invention relates to a configuration method of a medium and heavy plate roll system with consideration of both rolling stability and cross-section shape, in particular to a fit way between a working roll and a supporting roll in different periods of service life of medium and heavy plate supporting roll. By comprehensively considering the impacts of a roll gap on the rolling stability and influencing factors of cross-section shape control, the invention provides the following scheme: the six-time polynomial curve supporting roll with big roll diameter at the middle and small roll diameter at two ends is adopted on a medium and heavy plate mill, and the six-time polynomial curve working roll with the small roll diameter at the middle and the big roll diameter at two ends is adopted for matching with the supporting roll; and the six-time polynomial curve working roll with the big roll diameter at the middle and the small roll diameter at two ends is adopted for matching with the supporting roll after abrasion during the later stage of the service life of the supporting roll. The configuration method of the roll system can solve the contradiction between the stability of medium and heavy plate rolling and the control of the cross-section shape, and the field application can obtain significant effects.

The invention relates to a sheet billet continuous casting and rolling production line and mainly solves the technical problems of high rigidity and low surface quality of produced sheet billets of the prior production line. The invention adopts a technical scheme that: the sheet billet continuous casting and rolling production line is sequentially provided with the following production line equipment: a continuous casting machine, swinging shears, a roller-hearth tunnel furnace, a descaling unit, a vertical roll, a rough mill, a coil box, a ultrafast water-cooling device, flying shears, a finishing mill, a laminar flow-cooling and ultrafast water-cooling device and a coiling machine, wherein a secondary descaling unit can be arranged between the flying shears and the finishing mill; and the continuous casting machine adopts two double flow roller-hearth tunnel heating furnaces, combines two flows of the two continuous casting machines into one flow through a transverse moving machineand is connected with a rolling line. The invention is mainly used for continuous casting and rolling of sheet billets.

The present invention relates to a light-size round steel continuous-rolling method. It adopts a box-square-oval-round-oval-round system and makes the blank undergo the process of continuous rolling treatment by means of alternative six stands of vertical mills and horizontal mills so as to obtain the finished product, and before intermediate round pass stand and round former stand an inlet guide wheel is set.

The invention relates to the manufacturing of aluminum alloy materials, in particular to an aluminum foil material for manufacturing an anti-fake bottle cover and a manufacturing method of the aluminum foil for the bottle cover. According to the invention, the aluminum foil material for the bottle cover comprises the following alloy components in percentage by weight: 0.55-0.65 % of Si (Silicon), 0.75-0.85 % of Fe (Ferrum), 0.03-0.15 % of Cu (Copper), 0.05 % of Mn (Manganese), 0.05 % of Mg (Magnesium), 0.05 % of Cr (Chromium), 0.05 % of Zn (Zinc), 0.05 % of Ti (Titanium) and the balance of Al (Aluminum). According to the invention, the material is optimized on the basis of the 8011 alloy, is integrated with the advantages of the 8011 alloy, has the advantages of high surface quality, high strength, good rupture strength and good rolling stability and can be used for effectively increasing the production efficiency and the yield. The aluminum foil material is completely comparable to hot rolled aluminum foil blanks in finished product quality and the rolling performance.

The invention discloses 700MPa-grade cold rolled steel plate with high weather resistance and a preparation method thereof. In the invention, a thin plate black continuous casting and continuous rolling flow is adopted. The refined molten steel mainly comprises the following chemical components: 0.03 to 0.07 weight percent of C, less than or equal to 0.35 weight percent of Si, 0.4 to 1.8 weight percent of Mn, less than or equal to 0.020 weight percent of P, less than or equal to 0.010 weight percent of S, 0.25 to 0.50 weight percent of Cu, 0.25 to 0.80 weight percent of Cr, 0.05 to 0.30 weight percent of Ni, 0.06 to 0.20 weight percent of Ti, and the balance of Fe and inevitable impurities. In an annealing process, steel is annealed in a cover annealing furnace at the temperature of 500 DEG C to an A1 transition point. The yield strength of the cold rolled steel plate with high weather resistance exceeds 700MPa, and the elongation rate is over 5 percent, and the cold rolled steel plate has high machinability and high weather resistance.

The invention discloses an emulsified liquid total flow setting method during cold rolling of a double-rack six-roller mill. On the basis of a large number of field tests and theoretical researches, giving consideration to equipment characteristics of the double-rack six-roller mill and process characteristics of high-stage automobile sheet rolling, an emulsified liquid total flow optimization setting technology suitable for the high-stage automobile sheet cold rolling process of the double-rack six-roller mill is provided on the basis that sheet shape, surface quality and rolling stability comprehensive control indicators are introduced; three functions of improving the sheet shape quality of finished strip steel to the maximum degree, reducing the occurrence probability of hot slip damage to improve the product surface quality and avoiding slip to the maximum degree so as to improve the rolling stability can be achieved through the technology.

The invention discloses a temperature difference control method for rolling pieces for a steckel mill. The method includes steps of measuring initial temperature of the rolling pieces; calculating discharging target temperature value of a temperature complement furnace and heating the rolling pieces according to the target temperature value; calculating a set value of rolling speed of each rolling step and performing controlled rolling at each step according to the set value to reduce temperature difference; and measuring actual temperature of an exit and an entrance of a rolling mill and comparing the actual temperature with corresponding values to realize self-learning of the model and enhance calculating precision of the model. By the method, the temperature differences among the head, the middle and the tail of each rolling piece are reduced greatly, and rolling stability and quality of finished products and production ability of a production line are enhanced.

The invention discloses a three-roller centering device for a rolling mill, which solves the problem that the guide device can not adapt steel pipes with different specifications. The three-roller centering device for the rolling mill comprises an upper guide roller driving cylinder (2) and a lower guide roller driving cylinder (3) which are arranged on a rack (1). An L-shaped swing arm (4), a T-shaped swing arm (6) and a reversed V-shaped swing arm (8) are hinged on the rack (1), a first adjusting pad (5) which can adjust the amplitude of swing of the L-shaped swing arm (4) is arranged between the L-shaped swing arm (4) and the rack (1), and a second adjusting pad (7) which can adjust the amplitude of swing of the T-shaped swing arm (6) is arranged between the T-shaped swing arm (6) and the rack (1). A hinged shaft (18) connected with a driving motor (20) is provided with a driving sprocket (17), and a driven sprocket (15) is arranged on a shaft (14) of one end of a lower left guide roller (10). A chain (16) is arranged between the driven sprocket (15) and the driving sprocket (17). The three-roller centering device for the rolling mill adapts the steel pipes with different specifications and reduces the operation cost of equipment.

The invention discloses a method for realizing flow per second balance among hot rolling continuous mill stands through rolling mill speed compensation, relates to the field of hot-rolling production process control, and aims to solve the problem of flow per second imbalance in the head wearing process of a hot rolling strip steel. The practical roll speed for finish rolling of each frame and the roll speed regulating quantity required by loop control is acquired from a level 1 computer according to the regulating process of the roll speed for finish rolling of each frame required by loop control in a threading process, specification-classifying self-adaptive learning is performed on the change rate of the roll speed required by the loop control according to steel type*thickness*frame, and the roll speed is corrected by adopting a latest learning coefficient during setting calculation of a next roll of strip steel in order that the flow per second among the finish-rolled frames tends to be balanced. By adopting the method, the phenomena of large loop rise or no loop rise, finish rolling steel scrap, width reduction and the like can be reduced, and the rolling stability of a finish rolling process is improved remarkably.

A multilink rear axle comprises a wheel carrier, a leaf spring, a first lower control arm, an upper control arm, and at least one member. The wheel carrier can rotatably support a wheel of the vehicle. The leaf spring can extend in a width direction of the vehicle that is transverse to a longitudinal direction of the vehicle. The first lower control arm can extend in the width direction and is pivotably coupled to the wheel carrier at a rear half thereof. The upper control arm can extend in the width direction and can be pivotably coupled to the wheel carrier at an attachment point that is offset from the rotation axis of the supported wheel in the longitudinal direction by less than or equal to 100 mm. The at least one member can pivotably couple the leaf spring to the upper control arm.

The invention relates to the preparation of an aluminum alloy material, in particular to a household aluminum foil material and a preparation method of the household aluminum foil. The aluminum alloy material comprises the following alloy components by weight percent: 0.2-0.25% of Si, 0.77-0.83% of Fe, 0.05% of Cu, 0.1% of Zn, 0.05% of Ti and the balance Al. The material combines the advantages of the series 1 alloy and the 8011 alloy, has low strength, high elongation rate, high surface quality and good rolling stability; and by adopting the material, the production efficiency and yield can be effectively increased and the production cost can be reduced. The hole number of the household aluminum foil prepared by the method is below 200 per square meter, the tensile strength is 80-100Mpa and the elongation rate is no less than 1%.

The invention discloses a steel reheating method for a stepping type heating furnace. In the steel heating process, a walking beam is mainly in an operating state or idling state; when the walking beam is in the idling state, the walking beam starts automatic high-low lifting motion; and when the walking beam is in the operating state, the walking beam stops the automatic high-low lifting motion. By the high-low automatic jump steel heating of the walking beam at the quench time before steel tapping and the reasonable setting of the staying time of the walking beam on high and low positions, the serious water mark temperature difference caused by overlong time of a plate blank stayed on a fixed beam can be effectively eliminated, and the performance requirements on special products such as greatly improving the dimensional accuracy of products, enhancing the rolling stability of a finishing mill, greatly improving silicon steel and the like can be met.