CN1177531A

CN1177531A - Synchronous centripetal method for welding bottom of metal storage tank

Info

Publication number: CN1177531A
Application number: CN 97105199
Authority: CN
Inventors: 薛世路; 白立东
Original assignee: Oil-Field Construction Engineering Co No 2 Liaohe Petroleum Exploration Burea
Current assignee: Oil-Field Construction Engineering Co No 2 Liaohe Petroleum Exploration Burea
Priority date: 1997-07-31
Filing date: 1997-07-31
Publication date: 1998-04-01

Abstract

The present invention relates to a welding method using synchronous centripetal process to weld the bottom of metal tank. It includes the following steps: firsty, 300 m/m brodside sheet outside of the tank bottom and wall sheet of the bottom layer are welded, and formed into an initial rigid fixing ring; other tank bottom sheet is divided into some concentric rings; then all the welding seams can be welded one by one from tank bottom edge to centre to implement tank bottom welding operation having no need of other reinforcement supporting material. Said method can overcome the weld defects of producing T-shaped crack and residual stress capable of damaging tank body quality, etc. which are present in existent technology, and is simple in construction, easy to implement, can be extensively used to manufacture oil storage tank body.

Description

The synchronous entad method of method weld metal storage tank bottom

The invention belongs to the machining category, particularly a kind of synchronous entad process of weld metal storage tank bottom.

Vertical garden tubular steel basin during fabrication at first weldering tie tank skin and then carry out jar at the bottom of weldering to tie be an individual difficult problem always.The mass defect that is prone in such engineering is that rough and uneven in surface " fourth " word commissure that reaches cracks behind jar back welding, for solving a difficult problem, once segmentation skip welding at the bottom of taking jar, weld short weld seam from the center to external welding or elder generation, measures such as the long weld seam of back weldering, but the still a large amount of existence of problem such as rough and uneven in surface " fourth " word weld seam cracks behind jar back welding, forming the local crowning or jar end at the bottom of making because of weldering knot method is improper in a word jar forms a strip projected parts and causes between tank bottom and the tank base bitumen sand cushion space greatly, the maximum can reach 120mm, and it is of common occurrence that tank body is influenced by moment of flexure to cause the weld seam position phenomenon that fractures after oil storage tank is full of liquid; A kind ofly the outside 300m/m broadside listrium and bottom wallboard at the bottom of the jar can be welded into one and initially rigidly fix circle, then all the other tank bottoms are divided into several donuts, finishing each garden ring inside weld by the jar periphery one by one to the center is that the method that does not occur scraggly phenomenon and " fourth " word crackle after entad method weld metal storage tank bottom method can overcome jar back welding knot synchronously of vertical garden tubular is not reported.

Purpose of the present invention is a kind of synchronous entad method of weld metal storage tank bottom that proposes in order to overcome above-mentioned shortcoming.

The present invention is achieved in that

At first center plate bar 1 is pressed the design attitude yaw on certain position, finish peripheral bilge ways 3 butt welds of center plate bar then, welding direction is welded knot outside to inside from the garden; Second finish jar at the bottom of and outside fillet (weld) in the hoop between the tank skin 2, weld along garden Zhou Junbu by some people; The 3rd finishes side plate 3 lap welds; The 4th finishes lap weld between side plate and the center plate; The 5th step was finished the weld seam on the center plate: welding method is as follows: mark several concentric circles at the bottom of the jar, its diameter is according to reducing 800m/m, these concentric gardens are divided into the endless belt that several width are 400m/m at the bottom of with jar, welding sequence elder generation is from the endless belt of ragged edge, finish the weld seam in each ring successively, when each ring inside weld welding, welding rod fortune arc is from operation outside to inside, direction shown in arrow among the figure.

Just can finish task proposed by the invention by above-mentioned five steps.

Advantage of the present invention: take jar bilge ways butt weld in the jar lateral, to weld knot when tying owing to weld, this just makes jar bilge ways butted part fully fit to the bitumen sand cushion surface under the plate, when having welded between jar end and the tank skin after the hoop angle welding, the jar bilge ways partly reaches and descends rigidity garden ring of the common formation in joint tank skin bottom most, when taking of welding side plate lap weld and center plate saved weld seam, because the contraction of weld seam can make tank bottom that a power that moves down is arranged; Adopted during in addition owing to the weldering knot and divided boxing knot mode in the endless belt, the weld seam that in the endless belt, just weld concerning jar at the bottom of can produce three component: one is that cohesive force p puts down, another power be along bitumen sand cushion surface gradient direction and gradient normal direction pulling force p draw, p hangs down, by force resolution as seen, the pot bottom branch that has welded under p draws effect has the trend of being evened up; Under p hangs down effect, the pot bottom branch that has welded is pressed towards asphaltic sands surface trend, tank bottom by this construction method can cling to the bitumen sand cushion surface, and tank bottom is not influenced by residual stress can and produce rough and uneven in surface phenomenon (Fig. 2) jar end flatness qualification rate and reach 100%; To take welding method be to utilize weld seam to shrink to reach the smooth appearance that has reduced " fourth " word seam crackle of tank bottom in the present invention in addition, secondly the shortcoming of rough and uneven in surface and crackle at the bottom of will long weld seam when the weldering knot being decomposed into weldering knot method in each annulus and having overcome long weld seam weldering knot and be prone to jar, thereby adopted and can not need in addition that reinforcement material supports at the bottom of jar at the bottom of the present technique welded tank.Present technique construction is simple, does not need to increase in addition special equipment, therefore can be widely used in the vertical and cylindrical steel storage tank weldering knot of 3 tens meter 3 of several myriametre.

The present invention is provided by following examples:

Illustrated below in conjunction with accompanying drawing

Accompanying drawing 1. jar back weldings of the present invention connect programme diagram

2. weld seam convergent force exploded view of the present invention

Embodiment 1:

On the right tank bottom (center plate) 1 of group,, its base plate is fixed, then the butt weld of the 300m/m width edge plate 3 of weldering knot tank bottom outmost turns every 500m/m spacing spot welding 5-6m/m weld bond; Weld angle welding between orlop tank shell longitudinal seam and tank skin and the tank bottom again; The postwelding shovel is opened spot welding place between jar bilge ways 3 and side plate and the center plate 1, and organize again and make it be adjacent to tank base side plate 3, at last, mark several concentric circles at jar to be welded at the end, its semidiameter is from being followed successively by outside to inside after a jar end that 150m/m, 250m/m, 500m/m, 500m/m will not weld is divided into width and is 150m/m, 250m/m, several endless belts of 500m/m, 500m/m, begin from outer shroud, welded each ring inside weld successively.Embodiment 2:

Every weld seam welding direction will from outer several in, weld each ring inside weld successively when the welding side plate welded in the ring that stitches the place with being connected of center plate, first toe plate welding seams is burn-on and is stated connection and stitch, and welds center plate 1 weld seam at last.

Embodiment 3:

Jar end flatness behind the weldering knot reaches 100%, flawless, and the jar end during construction, should meet the quality standard of the world " construction of vertical and cylindrical steel arch-roof tank and acceptance specification " in (GBJ128-90).

Claims

1. synchronous method at the bottom of the method weldering knot metal can jar entad; It is characterized in that: earlier with center plate (1) by the design yaw on certain position, finish peripheral bilge ways (3) butt weld of center plate successively, weldering knot direction inwardly can be welded knot from the round can outer rim, and then the weld seam at exterior angle at the bottom of finishing jar and in the hoop between the tank skin; And side plate (3) lap weld, lap weld between peripheral bilge ways and the center plate, the weldering knot at the bottom of the weld seam on the weldering knot center plate can be finished jar at last; When knot weldering, should on tank body, mark several concentric circles, its diameter reduces 800m/m successively, and these concentric circles are divided into the endless belt that several width are 400m/m at the bottom of with jar, earlier from the endless belt of ragged edge, finish each ring inside weld successively.

2. the method at the bottom of the weldering knot metal can jar according to claim 1; It is characterized in that each ring inside weld when welding welding rod fortune arc is from outside to inside.

3. the method at the bottom of the weldering knot metal can jar according to claim 1; It is characterized in that on the right tank bottom (center plate 1) of group every the 500m/m spacing, spot welding 5-6m/m, weld bond is fixed its base plate, side plate (3) is tied in weldering successively, the tank shell longitudinal seam, angle welding between tank skin and the tank bottom, and then spot welding place between a jar feather edge (3) and side plate and the center plate (1) left by shovel, and organize the basis that it is close to jar to side plate (3) again, at last, jar in not weldering marks several concentric circles at the end, its semidiameter certainly outside to inside, be followed successively by 150m/m, 250m/m, 500m/m, 500m/m, it is 150m/m that a jar end of not welding is divided into width, 250m/m, 500m/m, behind several endless belts of 500m/m, begin, welded the weld seam in each ring successively from outer shroud.