100 Q mechanical knowledge 
A: What is called the projection plane parallel to the line? What are the straight-line projection of? 
A: When a straight line parallel to the projection plane, the call for the projection plane parallel to the line. The straight-line projection of authenticity. 
Second: has the thickness of any sheet metal, and what to do diagram of plate thickness on the shape and size of an impact? 
A: The expansion plan for the shape and size is influential. 
Three: ball, ring and spiral surface components, how the surface are developable surface? 
A: The surface is not developable surface are. 
Fourth: For the commencement of the prism and the cylinder, the general application of what is expansion? 
A: The general application of parallel expansion. 
V: orthogonal conical tube and cylindrical tube intersection, the intersection often obtained by using what? 
A: usually obtained by using auxiliary plane. 
Six: the real demand curve of a long multi-purpose which law? 
A: The multi-start method. 
Seven: friction press overload, only what is and what caused the slip between, and not damage the parts? 
A: The flywheel will only cause the friction between the sliding plate, and will not damage the parts. 
Eight: open the slider crank press tour, what can change and what to regulate? 
A: Yes, by changing the upper part of the eccentric rod; spindle center distance to adjust. 
Nine: In the drawing, extrusion processes, because the reasons for die clearance, so what is the material the more stringent requirements? 
A: The thickness of the material the more stringent tolerances. 
X: punching the sheet where the separation process can be divided into three stages? 
A: 1: elastic deformation, 2: plastic deformation, 3: crack separation. 
November: what more drawing coefficient, the greater the deformation drawing materials? 
A: The smaller the drawing coefficient, the greater the deformation drawing materials. 
Twelve: What is cold stamping? 
A: at room temperature for the stamping process is called cold stamping. 
Thirteen: What is a complex process? 
A: The two or more of the basic processes are combined, in the press to complete a trip, called composite processes. 
Fourth: What is a simple blanking die? 
A: In a press trip, only to complete a blanking process dies. 
Fifth: What is the composite blanking die? 
A: In a press trip, you can also complete the multi-channel processes Die. 
XVI: how to interpret the blanking force correction factor Kp? 
A: In the calculation of punching force, consider the pattern edge wear, die clearance, material factors such as mechanical properties, and select the safety factor, under normal circumstances, take Kp is equal to 13. 
Seventeen: What is the oblique edge blanking? 
A: The oblique edge blanking is a way to reduce the blanking force. Edge is to make a relatively blank at an angle of tilt, so that when the die edge blanking of contact with the billet is gradual, so uniform and stable load. 
Eighth: What is the stepped punch punch? 
A: The ladder is to reduce the blanking punch a method of blanking force. While punching in a porous, it will punch into the ladder relative to the form of uneven stock, punching punching force can be effectively distributed. 
Nineteen: open and closed crank press crank press any different? 
A: In structure, the open bed crank press was C-shaped structure, the partial pieces are from the rod axis rotary motion into reciprocating motion up and down the slide. Closed Press the bed into a frame-shaped structure, instead of the eccentric shaft by the crank. 
Twenty: open and closed crank press crank press have their own characteristics? 
A: The open-crank press the C-shaped bed on three sides open, especially for the edge of the large sheet of sheet metal stamping process. But this form of less rigid bed structure itself, which can bear the load small. Closed frame structure crank press restrictions by column, table space is limited, do gymnastics space, thus stamping around the size of a certain limit. Frame-shaped rigid bed structure, which bear the load of the uniform. 

The twenty-first: the factors that affect the material stamping what? 
A: (1) Flexible (2) plastic (3) hardness (4) the quality of the material surface state (5) material thickness tolerances. 
Twenty-two: die clearance for punching quality? 
A: convex, the gap between the die over an hour, punch the material near the crack edge stagger out some distance, so that the upper and lower parts of the middle of the two materials as the pattern of the punching shear was the second time the quality of the section. The gap is too large, the material near the punch edge crack to some distance in the staggered, the material was great tension, the edge of the burr material, collapse and slope angle of greater cross-section will also affect the quality of blanking. In addition, the gap is too small or too large, both the size of the blanking bias to a certain extent. 
Twenty-three: the minimum bend radius of material What are the factors? 
A: 1: Mechanical properties of materials and heat treatment, 2: the workpiece bending angle, 3: geometric shape and size of materials, 4: bending direction, 5: Other aspects, such as material thickness, surface and on the side of quality. 
Round: Bending the neutral layer of material is how to define it? 
A: The material in bending, by stretching the outer, inner layer by extrusion, in its cross section is bound to have a pull from both, without compression of the transition layer, stress is almost zero, this transition layer known as the material neutral layer. 
Twenty-five: beam composed of multiple components corrected, we must fully consider the joint relationship between what? 
A: To give full consideration to the joint relationship between the beams. 
Twenty-six: The correction of the deformation of sheet steel structure, it must ensure that any compliance requirements? 
A: The framework must ensure that all types to meet the requirements before they can consider the plate to correct. 
Twenty-seven: point-like heating plus hot and what about plates? Plus how the distance between hot spots? 
A: The heating plus hot spots and plate thickness. Increase the distance between the hot uniform. 
Twenty-eight: What is called the longitudinal contraction? 
A: The metal around the weld and weld a form of contraction, the contraction along the weld length, called the longitudinal contraction. 
Twenty-nine: What is known as the lateral contraction? 
A: contraction of the weld and weld metal near a form, means the direction perpendicular to the length of the contraction of the weld, said lateral contraction. 
Thirty: steel structure of the internal stress is produced? 
A: The welding process for welding structural terms, is a non-uniform heating and cooling process, is produced in the welding structure of the main reasons for stress. In addition, the steel structure of the various parts, in its blank state or after processing into parts, there may exist residual stress in the assembly and welding as a whole, these residual stress components may be assembled in a new internal stress. 
Thirty-one: Why are some pieces of steel after welding to eliminate stress to deal with? 
A: Some pieces of welded steel, the steel is better because of no obvious distortion, but the welding stress is quite large, in the steel used for some time, may be released for some reason caused by deformation, resulting in the destruction. Therefore, some of the important uses of steel, such as pressure vessels, hazardous media containers, boilers, etc., after welding, using a variety of methods to eliminate stress treatment, the purpose is to prevent the steel structure of the internal stress on the components harm. 
Thirty: welding deformation of steel structure What are the factors? 
A: The welding deformation of steel structure design and process factors are two aspects. Design refers to the structural design is reasonable, the location of the weld, welding groove forms and so on. Workmanship means the reasonable welding procedures, assembly and welding sequence, a variety of anti-distortion and anti-deformation method used, and the measures taken to eliminate stress. 
Xxxiii: How to understand the intrinsic link steel structure? 
A: The so-called steel structure, all of these various components by welding, riveting or other means, and bolted connections into one, these parts with each other, but also check each other to form an organic whole. 
Thirty: correction of deformation of steel structures is the gist of what? 
A: 1: Analysis of the causes deformation components and understand the deformation is the deformation caused by external force or internal stress caused by the deformation, 2: analysis of components of the inner link, find out the constraints of the various relationships among parts, 3: Choose correct correct position, the first to solve the major contradictions to resolve minor conflicts, 4: To understand and grasp the nature of the steel components used in order to prevent broken parts caused by correction, such as cracks or rebound. 5: In accordance with the actual situation to determine the correct approach, and a variety of methods and use the time of the order. 
Thirty-five: thin plate of steel structures in the deformation correction method which can only be used 
A: The deformation for sheet steel structure, but to use local heating (heating and is point-like) approach to correct. 
Thirty-six: point-like heat distortion correction sheet, should pay attention to what? 
A: It should be noted: 1: The heating temperature should be appropriate, both to be able to enough to cause plastic deformation of steel, the temperature can not be too high, usually 650-800. 2: Add hot spot size and the distance between point and point to the right . Under normal circumstances, depending on the thickness of the plate, arranged to be uniform, mostly plum-shaped layout. 3: water quench and wood hammer steel hammer is designed to speed up the fiber group contraction. 4: Do not heat when the welding torch back and forth shaking bundle of small flame to the vertical plate, plus hot and not more, in order to avoid undue stress to increase. 
Thirty-seven: What is the framework of the deformation characteristics of class? 
A: The framework of the class component parts are more restricted in the structure between each other stronger deformation of each other greatly. 
Thirty-eight: simmer round billet roll bending machine, generally is heated to, right? 
A: Wrong. 
Thirty-nine: heating curve, the material should be heated to the number of degrees? And heated to what? Operating want? End of the temperature not lower than the number of degrees? 
A: The material should be heated to 950-1100. At the same time the heating should be uniform, the end temperature of not less than 700. 
Forty: roll bending cylinder defects that may occur when there? 
A: The roll bending cylinder defects that may occur when the crooked, the curvature range, curvature is too large, the middle drum and so on. 
Forty-one: Roll cone, as long as the regulation on the central axis into the kind of position, while the axis of the roller blank bus always coincide with the fan, you can roll into a cone? 
A: The regulation into the tilt position. 
Forty: Roller cone, an increase in what the edge of the billet friction? What is the speed of the shift speed is lower than what shift? 
A: The increase in stock of small mouth of the friction, the small mouth moved into a slower than the speed of a large population shift. 
Forty-three: There are many forms the core axis of the elbow, with round-style, pointed style, hook-like and what type? 
A: and one-way joint type, universal type and so on. 
Forty-four: No core pipe is not mandrel, bending machine in the process adopted to control the deformation of the pipe bend any way? 
A: Bending deformation on the use of anti-bend section of the process to control the deformation method. 
Forty-five: When bending the bending radius is larger than the diameter of how many times, usually with no core pipe? 
Answer: more than 1.5 times. 
Forty-six: extrusion plastic pipe is the use of metal, at room temperature state, what with the tube pressed into the mold to form a pipe elbow? 
A: The tube pressed into the mold with a curved shape to form a pipe elbow. 
Forty-seven: extrusion bending, the tube being subject to bending moment effects, but also by what and axial force in the opposite direction with what force? 
A: also by the axial and axial force in the opposite direction with the friction effect. 
Forty-eight: This paper describes the process of spheronization blank roll bending machine? 
A: Roll, the stock placed in spheronization machine, between the lower rollers, the rollers rotate, and through the upper and lower friction between the roller and the role of stock, so stock move, thus making the formation of bending. 
Forty-nine: four-axis machine rounded What are the advantages? 
A: The advantages of four-axis machine can be rounded to two ends of the sheet can be rolled forward to eliminate both ends of the straight head, rounded than the three-axis machine simplifies the process, reducing the workload, improve production efficiency. 
Fifty: Rolling cone method are there? 
A: The rolling method can be divided into partitions, rectangles, feeding method, rotation feeding method, small mouth deceleration method. 
Fifty-one: how to reduce the bending pipe cross-section of the ellipse? 
A: bending pipe, in order to reduce the cross-section of the ellipse, in the production process, often used in the filler pipe in Canada, or tapered roller pressure in the pipe slot outside or inside the mandrel pipe penetration method of bending. 
Fifty-two: What are the advantages spoon-type shaft? 
A: Spoon a large mandrel bearing surface and the outer wall, anti-tip-style flat is better than a good, hard surface of the pipe bending wrinkle, spoon-type spindle manufacturing is also more convenient, the application to teach a wide range. 
Fifty-three: no more than a core-core pipe bend What are the advantages? 
A: (1) reduce the bend a lot of preparation before the core, etc., to improve the efficiency of production (2) to avoid shaft manufacturing, reducing costs. (3) the tube does not require lubrication, saving lubricant and fuel injection processes. (4) to ensure the quality of pipe. (5) No spindle and the wall friction and reduce the Bend of the moment, thereby extending the life of bender. 
Fifty-four: mechanical drive type bending machine is how to drive? 
A: The mechanical drive type bending machine is determined by the motor through the gear shaft, reduction gear, worm gear, driven bending mode rotation. 
Fifty-five: the shelves in the wheel cylinder assembly of the annular phase, each of the wheel position of the horizontal distance and height can not be the same, so the assembly, the cylinder can be concentric, right? 
A; wrong. 
Fifty-six; if there is a deviation in diameter of two cylindrical sections, the assembly should be in the larger diameter cylindrical section of the booster, so the two concentric cylindrical shell access, right? 
A: Wrong. 
Fifty-seven: welding pieces of the larger linear expansion coefficient of the material after welding the greater the shrinkage of the weld, right? 
Answer: Yes. 
Fifty-eight: shrinkage after welding of carbon steel, stainless steel and aluminum than the big, right? 
A: Wrong. 
Fifty-nine: The hammer welding method to prevent the deformation of multi-layer welding, it should in the first layer and the last layer applied hammer, right? 
A: Wrong. 
Sixty: the rigid fixation of the weld zone will cause great stress, so this method is suitable for medium carbon steel and alloy steel, right? 
A: Wrong. 
Sixty-one: what is often used to assemble the cylinder assembly to raise the efficiency of longitudinal joints? 
A: The regular use of lever, screw tensioner efficiency. 
Sixty-two: What is often used to adjust the cylinder ellipticity occur? 
A: Push the radial support device. 
Sixty-three: the slender cylindrical section of docking, what the assembly can be guaranteed not to bend the whole? 
A: The drum roll cages to ensure that the overall assembly can not be bent. 
Sixty-four: vertical cylinder mounted butt girth, the use of any girth clamping and alignment can achieve better results, while to obtain the required clearance? 
A: The use of wedge clamping section and alignment fixture to girth, can achieve better results, but also to obtain the required clearance. 
Sixty-five: vertical cylinder fitted girth lap time, what position? Finally, what clamping? 
A: The block of iron positioning. Finally, Article clamping wedge-shaped cones. 
Sixty-six: What constitutes the main rivet gun? 
A: The main by the handle, the gun body, trigger, fittings and other components. 
Sixty-seven: cold riveting ago, to eliminate the plastic hardening to improve the material, the rivet must be what to do? 
A: You must be annealed. 
Sixty-eight: rivet is formed by what and what? 
A: Yes, formed by the hollow rivet and the mandrel. 
Sixty-nine: weld cooling, What happens in the weld area? Leaving what the body produces welding power? 
A: weld cooling, shrinkage in the weld area, leaving the welding body to produce stress. 
Seventy: The multi-layer welding, the maximum contraction caused by the first layer, the second layer is the first layer shrinkage shrinkage of about per cent of scores? The third layer is about several percent of the first layer? 
A: (1) twenty percent (2) five percent to ten percent. 
Seventy-one: the main beam overhead crane is generally much camber? 
A: To a thousand. 
Seventy: bridge crane from the three components which? 
A: The bridge, running organizations, load the car. 
Seventy-three: the structure of box girder lines consist? 
A: from the upper cover, lower cover, web, the length of rib and other components. 
Seventy-four: box-line structure of the degree of the main beam of the web surface, in the one meter length of the maximum wave peak pressure area is how much? How much of the tension zone? 
A: The compression zone is 0.7t: on the tension zone for the 1.2t. 
Seventy-five: Box cutting line when the beam web, how much headroom? How many away from the center can not have a connection? 
A: A five-thousandth point margin: two meters away from the center can not have a connector. 
Seventy-six: According to the purposes and needs, the type of steel roof truss, the shape is varied, generally what roof? 
A: There are triangle, trapezoid, ball, net-shaped roof and so on. 
Seventy-seven: general height of the triangle roof truss span how much? 
A: Yes, one-fourth to one-fifth. 
Seventy-eight: trapezoidal roof height of the number of span? 
A: In order to sixth to one-twelfth. 
Seventy-nine: what method to use more steel roof trusses for assembly? 
A: The multi-profiling method used for assembly. 
Eighty: What is cold riveting? 
A: Under the rivet riveted at room temperature, called cold riveting. 
Eighty-one: What is the pull riveting? 
A: The pull is cold riveting riveting riveting another way. It uses compressed air as power hand or by special tools to make rivets and riveting piece was riveting. 
Eighty-two: What is hot riveting? 
A: The heating of the rivet rivet rivet called heat. 
Eighty-three: What is anti-deformation method? 
A: The analysis of weldments after welding may be the direction and size of the deformation in the welding weldment before doing so to be the same size, the deformation in the opposite direction, to offset or compensate for the deformation after welding, so that after welding to prevent distortion head to, this method is called anti-deformation method. 
Eighty-four: What is the rigid fixation? 
A: The use of assembly fixtures, or temporary support, the mutual position of the welding parts fixed to prevent deformation after welding method, called rigid fixation. 
Eighty-five: loft drawing Figure is made according to the construction drawings, right? 
A: Wrong. 
Eighty-six: developable surface than flat, there are cylindrical and conical surfaces, etc., right? 
Answer: Yes. 
Eighty-seven: expansion plan is all the Chart component on the surface of the corresponding part of the real long-term, right? 
Answer: Yes. 
Eighty-eight: If the line in the projection on three sides with the accumulation of a projector, then the other two projectors must have the truth, that is, real long-line response, right? 
A: Wrong. 
Eighty-nine: If the line on both sides of the projector are projected perpendicular to the axis of the clip, the third anti-plane projection will be a long line real, right? 
A: Wrong. 
Ninety: a straight line projection will always be a straight line, no other cases at all, right? 
A: Wrong. 
Ninety-one: general location of the line in the third view, real long reaction times, and sometimes do not respond real length, right? 
Answer: Yes. 
Ninety-two: solid line for the average long position, it is best obtained by using rotation, right? 
A: Wrong. 
Ninety-three: real long way to find a line parallel line method, triangle method and the radiation method, right? 
A: Wrong. 
Ninety-four: In the riveter or painted sheet metal production expansion plan in the common right triangle method, rotation, surface transformation and regional law, right? 
Answer: Yes. 
Ninety-five: start with a triangle shape, the key is to find the real length of the prime line, right? 
A: Wrong. 
Ninety-six: plane curve in response to the three views are real long, right? 
A: Wrong. 
Ninety-seven: prism, cylinder and cylinder surface and so the parallel line method can be used to start, right? 
Answer: Yes. 
Ninety-eight: triangle expansion method is applicable to all component surfaces of the profile lines intersect at one point in the form of the expansion, right? 
A: Wrong. 
Ninety-nine: Auxiliary demand side of Intersection line, the axis of rotation parallel to and responsive to real length, right? 
A: Wrong. 
91: What is the role of the drill shank? 
A: holding and passing the required drilling torque and axial force. 
92: taper shank drill the flat tail them? 
A: used to increase the transmission of torque, to avoid drill hole or drill in the spindle sleeve in the play. 
93: Some of the drill guide in what role? 
A: It can keep the bit cutting process integrity in drilling direction. Also has the role of cell wall light repair and parts, or cutting back some. 
94: When the drilled hole is about what undesirable phenomena occur? 
A: When the drill just drill through the workpiece reduces the axial resistance of a sudden, because drilling into the gap to the mechanical and elastic deformation of the sudden recovery of the drill bit will feed automatically into a large, resulting in broken drill bit or drilling quality reduced. 
95: What is the role of cutting fluid during drilling? 
A: reduce friction, reduce drill resistance and cutting temperature, cutting ability and improve the drill hole wall surface quality. 
96: What is cutting? 
A: is the cutting feed and cutting depth in general. 
97: What is the grinding? 
A: The wheel on the surface is to use the processing method. 
98: What is start? 
A: The surface of the metal structure or partial according to its actual shape of the order spread out on a flat surface is called to start the process. 
99: Plan There are several ways to start map? 
A: There are parallel to the line method, triangle, radiation method. 
100: Parallel Line Method start conditions? 
A: Yes, prime line component surface parallel to each other, and reflect the real length in the projection plane. 
101: thickness deal include? 
A: To determine the bending part of the neutral layer thickness and the elimination of interference. 
102: position of neutral layer thickness change and what factors? 
A: with the plate bending radius and sheet thickness. 
103: thickness handle intersecting pieces of the general principles? 
A: Expand the length of the component size of the neutral layer prevail, expand the figure at the height of the curve to touch the height of structures shall prevail. 
104: Setting out the main contents? 
A: The thickness processing, mapping and started to make the components under the number expected to start production of a model figure. 
105 riveter shearing equipment commonly used in what? 
A: There are gantry cutting, bevel cutting plate, disc cutting machines, punching shears combined punching and shearing machine. 
106: Bending at the number and arrangement of the roll axis which can be divided into several? 
A: The three rollers are divided into symmetric and asymmetric three roller, four-high three. 
107: Die by the structure can be divided into what? 
A: The model is divided into simple, with pillar die, compound die. 
108: Die composite structure is characterized by what? Material with a punch ups and downs of the role of both, the role was underway punching die punch. 
109: What is the punching power? 
A: means punching the greatest resistance to the mold material. 
110: punching sheet metal deformation process can be divided into separate what stage? 
A: The stage is divided into elastic deformation, plastic deformation and shear crack stage. 
111: What is the minimum bend radius? 
A: The damage does not occur in the material circumstances can the minimum bend radius. 
112: to reduce the resilience of the common method of bending pieces of what? 
A: There are amendments to mold method and the pressure correction method. 
113: blank holder with tension What is the purpose? 
A: The main components in order to prevent stretching the edge wrinkle. 
114: crank press crank them? 
A: It not only makes reciprocating rotary motion into linear motion, while amplification from the force. 
115: panel beaters hand-formed include? 
A: including bending, arched, pulling edge, curling, sewing and correct bite. 
116: What is the role model for development of shape? 
A: No material can be used to create molds and manufacture of milling separation model. 
117: What is put side? What are the methods to form? 
A: The deformation of the molding process, to extend parts of the edge of the material placed edge thinning operation is called. Methods of thinning and the formation of pull-thin. 
118: What is the pull edge? 
A: The use of pull side and income side of the method, the edges of sheet metal bending parts processed into curves. 
119: What is curling? 
A: To increase the rigidity and strength of the workpiece edge of the workpiece is called crimping the edges curl. 
120: What is biting seam? 
A: The two edges of the sheet or piece of sheet metal on both sides, and each clamping bite off switch, called bite seam. 
121: What challenge the thick handle? 
A: The thickness of the expansion plan for the elimination of the shape and size of the impact of the approach taken. 
122: Calculating the length of curved pieces of the general steps to start what? 
A: The bending part is divided into straight segments and arcs; the length of each section were calculated; will calculate the length of the sum. 
123: Under what circumstances material under the application section of the incision? 
A: angle, channel, beam bent knuckle. 
124: Which of the blanking process comprises several stages? 
A: The three phases. Elastic deformation stage; plastic deformation; shear crack stage. 
125: What is the punch? 
A: The use of red part of the template to the sheet metal along with another part of the closure of certain lines of separation between the stamping process. 
126: There are several bolt? 
A: There are two kinds: the role of the axial tensile load join planted; take the role of lateral connections. 
127: The locking bolt measures what? 
A: increasing friction; mechanical locking. 
128: What mechanical locking method? 
A: The cotter pin; washers; washers; series wire. 
129: What is the arc? 
A: gas medium between two electrodes in a strong and lasting discharge phenomenon. 
130: Which of the welding arc by a few components? 
A: by the cathode area; the anode and the arc formed. 
131: What are three electrode direction of movement? 
A: The move to the pool; along the welding direction; for lateral oscillation. 
132: spatial location of the weld can be classified according to several? 
A: is divided into welding, vertical welding, horizontal welding, overhead position welding. 
133: What characteristics of intersecting lines? 
A: The only two-body surface is also the dividing line between public and cable; in space is always closed. 
134: What is the intersection? 
A: two or more components consisting of the intersection geometry. 
135: factors that affect the quality of what is blanking? 
A: The mold space; does not coincide with the center line of punch and die; mold the work of the blunt edge wear. 
136: mold design general principles? 
A: The quality of the press guaranteed under the premise that strive to mold designed, easy to manufacture, process simple and low cost, easy to use. 
137: the purpose of calculation of rolling force? 
A: Yes, the correct choice for rolling equipment. 
138: What is the free bending? 
A: When bending the end of the punch, blank, die mutual agreement not occur after the impact effect. 
139: What is the calibration curve? 
A: mean punch, blank, die, and once after the impact of the three match, the role of the bending part from the correction. 
140: suppression of head is easy to produce what are they? 
Answer: wrinkles and from the package; straight edge pull mark indentation; outer surface of the micro-cracks; longitudinal tear; skewed; ellipse; diameter inconsistent. 
141: What is the Expansion? 
A: The use of deformation of the tube and tube sheet to seal and fastening the connection mode. 
142: calculation of blanking force What is the purpose? 
A: The capacity for rational choice and design of tooling equipment. 
143: the method used to reduce the blanking force? 
A: The oblique edge die; ladder die; heating die. 
144: Calculate the bending force What is the purpose? 
A: To select and design bending press mold. 
145: La deformation include? 
A: including: the extent to punch; material allows deformation of the extent of stretching. 
146: How to determine the number of stretch forming the workpiece? 
Answer: According to the maximum deformation of the workpiece is pulled and the material elongation. 
147: How to determine the stretching factor? 
A: depends on the material properties, stretching corners, the friction coefficient and whether pre-stretching. 
148: What materials are not suitable for cold Johnson? 
A: The high-carbon steel, high alloy steel, cast iron and other brittle materials. 
149: When the angle of complex deformation of their orthodontic order? 
A: The first correction of distortion, and then the final corrected bending angle distortion correction. 
150 caused by deformation of steel What are the reasons? 
A: One is caused by external forces, one is caused by internal stress. 
151: the method of welding residual stress elimination of what? 
A: The overall high-temperature tempering; local high-temperature tempering; thermal tensioning method; mechanical stretching method; vibration method. 
152: What is the overall deformation of welded? 
A: means that the whole structure of the shape and size changes. 
153: What is the Hammer exhibition law? 
A: By hammering the metal sheet of fibrous tissue elongation. 
154: How to determine the length of the rivet bar? 
A: According to the total thickness of the connected pieces, nails and the nail hole diameter of the gap, riveting and other factors to determine. 
155: riveting, rivet head is too small after the reason? 
A: Because the nail too short or the aperture. 
156: welding by the metal in which the state can be divided into several? 
A: divided into three types, welding, pressure welding, brazing. 
157: What is fusion welding? 
A: The use of local heating to achieve the molten weld joint approach. 
158: What is the clamp? 
A: is the use of force, so that after positioning the parts fixed, so that in the process to maintain the same position. 
159: What is six targeting rules? 
A: The six anchor points to limit the freedom of parts in space, in order to achieve fully determine the spatial location of parts. 
160: What is the relative parallel? 
A: The line refers to the part under test or face a baseline for the measurement of parallelism, or surface. 
161: What is the relative vertical? 
A: The line refers to the part or surface measured relative to baseline measurements or the degree of vertical surface. 
162: clip assembly for use with what kinds of work? 
A: The assembly tool; assembly fixture; assembly spreader. 
163: What are commonly used in the assembly of hanging? 
A: There are steel wire rope, chains, chain hoists and special spreader. 
164: Die There are several forms of guidance? 
A: There are guide post, guide sleeve and the guide plate in two forms. 
165: There are several components Die? 
A: The part of the work, materials, positioning part, discharging part and mold base components. 
166: What is the role of drawing die gap? 
A: reducing material and the friction between the die and die-line control of materials in the cavity flow. 
167: bite their structure can be divided into several joints? 
A: One bite can be divided into vertical slit; vertical double bite slit; horizontal flat seam and a variety of bite bite angle joints. 
168: When the force removed, the curved pieces have springback why? 
A: Yes, because the manual bending, sheet metal outer surface of the inner surface of tensile compression, it produces rebound. 
169: How to get cold and hot hog hog? 
A: Cold arched through the contraction of the edge of the sheet material placed in the middle panels get hot hog is contracted by heating sheet obtained. 
170: There are several ways pull edge? 
A: There are two types of pull with the edge of common tools, a type of tire is pulling edge. 
171: What is the revenue side? 
A: The revenue side is to make sheet metal wrinkling, and then extend recovery to prevent wrinkling in the case of flattened, so that reduced the length of sheet is shrinking, so that the thickness increases. 
172; income side of the basic principles of that? 
A: The principle is curved for convex edge of the workpiece shape is mainly the outer edge of curved plane shrinkage and thickening of the material becomes shorter, forcing the standing seam curved shape. 
173: What is the purpose of correction? 
A: Yes, through the imposition of force or local heating, so that longer fibers shorten, shorter fiber elongation, and finally to achieve the correct layers of fiber consistency purposes. 
174: What is the principle of flame rectification? 
A: is the use of metal deformation produced by local heating to offset the original deformation, the purpose of correction. 
175: corrective effect of the flame What are the factors? 
A: There are parts of the rigid; heating position; flame heat; heating and cooling areas. 
176: Correction of the heating flame Which ocean? 
Answer: a bit like, linear and triangle heating. 
177: determine what factors process margin? 
A: Setting out the impact of errors; part of the processing error; assembly error of; welding deformation; correction of the flame. 
178: model according to their use can be divided into the categories? 
A: No materials can be divided into model, shape model, a model and template for positioning. 
179: What are the methods like painting? 
A: There are two kind of direct painting method and the transition to drawing-like method. 
180: Setting out how the baseline general election? 
A: In the two perpendicular line or plane; to two central line as the base line; in a plane and a center line as the benchmark. 
181: What is the loft tolerance? 
A: The sample came alive again in the process, due to measuring tools and instruments setting out the level of precision and operational factors, implementation plans will be a certain kind of size bias to the bias control in a certain range, called lofting allowable error. 
182: Structure Lofting include? 
A: To determine the location and connection with the form of ministries; based on the actual production and processing capacity to give the necessary modifications; calculation or the amount of material to take part in the actual length and shape of plane parts; design tire tool or tire rack. 
183: Find real length of the straight line method are there? 
A: The rotation method; right triangle method; Exchange Surface; extension method. 
184: Right Triangle Method of drawing a long line real laws? 
A: Yes, in any projection plane with the line of projection as a right-angle triangle edge, while the corresponding projection for the surface with a vertical length of projection axis angle as the other side, the actual length of the hypotenuse is the line segment. 
185: What is realistic and long rotation method? 
A: The general position is that the space around a fixed axis of rotation into parallel lines, the line parallel to the projection plane in the projection reflects the real length. 
186: demand curve which real long way? 
A: surface transformation; expansion. 
187: What is the surface transformation? 
A: is a separate curve of a new projection plane and parallel to, the curve reflects the actual length of the projection surface. 
188: What is expansion? 
A: Yes, view the curve of a straight length, while maintaining the height of the other view, made the same start line is that all the requirements.