CN2452642Y

CN2452642Y - Expanding head for tube expanding machine with pressure increasing decreasing function

Info

Publication number: CN2452642Y
Application number: CN 00259143
Authority: CN
Inventors: 郝俊文; 李培宁
Original assignee: East China University of Science and Technology
Current assignee: East China University of Science and Technology
Priority date: 2000-11-14
Filing date: 2000-11-14
Publication date: 2001-10-10
Anticipated expiration: 2010-11-14

Abstract

The utility model relates to an expansion head for tube expanding machine with pressure increasing and decreasing function, which is provided with a diameter change core shaft, a rubber elastomer and a fastener. The utility model can complete pressure regulation and expansion joint in one-step, and has the advantages of high productive efficiency, simple structure, science and convenient implementation. Because the utility model has the effect of pressure increasing and decreasing, the expansion head for tube expanding machine with pressure increasing and decreasing function can prevent tube plate whole yielding, and can achieve the purpose of protection tube plate and prevention generating leakage by the mutual influence of joints. The expansion head for tube expanding machine with pressure increasing and decreasing function can be used for connecting bellows or generating bellows, and has a low requirement to a power device. The operating cost of the expansion head for tube expanding machine with pressure increasing and decreasing function is low.

Description

A kind of expanding head of tube expander with pressure increasing decreasing function

It is the expand tube device of medium with rubber that the utility model relates to a kind of, relates in particular to the bloated head of expand tube device.

Electric tube expander is a kind of mechanical device commonly used, and this device can make that pipe deforms, and further can realize the fixing of pipe and other structures and is connected, and in the manufacturing of plant equipment such as heat exchanger, boiler and air-conditioning, is widely used.

The rubber expanded joint is the method that realizes the frequent use that tube-to-tube sheet connection connects in manufacturings such as heat exchanger.Advantages such as it is fast that the rubber expanded joint has expanded joint speed, and tube wall is not polluted, and expanded joint pressure is even, and the single hole operating cost is low.Expanding head of tube expander commonly used at present comprises an isodiametric mandrel, is arranged on the outer parts such as rubber elastomer, sealing ring and baffle ring of equal diameter mandrel, this traditional expanded joint device usually causes the plastic deformation even the surrender of whole tube sheet, the unloading of bloated good tube-to-tube sheet connection joint around causing, joint around making leaks, and influences the expanded joint quality.Therefore this device is improved, especially the head that expands is carried out new design, will have crucial meaning with the needs that satisfy machining.

The purpose of this utility model is to design a kind of expanding head of tube expander with pressure increasing decreasing function, to overcome the above-mentioned defective of prior art.

The technical conceive of invention is such:

In the expand tube process, expand tube pressure is directly proportional with axial compressive force, and the cross-sectional area at axial compressive force and this place is inversely proportional to, so, just can change the axial compressive force and the expand tube pressure at this place by the cross-sectional area that changes this place, realize local supercharging or decompression.For this reason, the inventor has designed a reducing mandrel.Its operation principle is such: when not rubbing or friction when very little, axial force remains unchanged in transmittance process substantially, axial compressive force equals axial force divided by cross-sectional area, when diameter is constant, cross-sectional area everywhere all equates, so axial compressive force everywhere equates all that also expand tube pressure also equates; When diameter changed, change had taken place in the cross-sectional area at reducing place, so the axial compressive force at this place also changes simultaneously, expand tube pressure also changes; When axle diameter diminished, it is big that the cross-sectional area of rubber elastomer becomes, and axial compressive force diminishes, and expand tube pressure diminishes and reached the decompression purpose; When axle diameter became big, the cross-sectional area of rubber elastomer diminished, and it is big that axial compressive force becomes, and it is big that expand tube pressure becomes, and reached the supercharging purpose.

When coefficient of friction is big, frictional force can make axial force successively decrease to the centre from two ends along axis, because change has taken place in mandrel middle part diameter, so the degree of successively decreasing of axial force can be strengthened or weaken: diameter reduces, the degree of successively decreasing is strengthened, and diameter increases, and the degree of successively decreasing weakens, objectively make expand tube pressure become vertically evenly even make the pressure of reduced diameter portion increase, reached the purpose of supercharging.

Realize the technical solution of the utility model:

The said bloated head of the utility model comprises:

A mandrel that becomes diameter, this mandrel is provided with one or more projection;

A rubber elastomer, this elastomer are provided with the groove that matches with projection on the mandrel, and elastomer sleeve and closely cooperates with mandrel outside mandrel, and the projection on the mandrel then embeds the groove on the elastomer;

Be arranged on the mandrel two ends, and sealing ring that abuts against with elastomer and the baffle ring that abuts against with sealing ring;

Being arranged on the mandrel end is used for mandrel, rubber elastomer, sealing ring and baffle ring are connected fastening all-in-one-piece securing member;

One end of mandrel is connected with power set, when rubber elastomer is under pressure in the end, will shrink along mandrel, and chap shortens.

Below will do detailed explanation to the utility model by accompanying drawing.

The bloated header structure schematic diagram that Fig. 1 has a projection for the mandrel middle part.

Fig. 2 is the schematic diagram of the rubber elastomer in shown in Figure 1 bloated.

Fig. 3 is the mandrel schematic diagram with two projectioies.

Fig. 4 is the mandrel schematic diagram with two monolateral angled protrusions.

Fig. 5 is protruding dismountable mandrel schematic diagram.

By Fig. 1 and Fig. 2 as seen, said bloated head comprises:

A mandrel 1 that becomes diameter, this mandrel is provided with a projection 8:

A rubber elastomer 2, this elastomer 2 are provided with the groove 11 that matches with projection 8 on the mandrel, and said elastomer 2 is enclosed within outside the mandrel 1, and closely cooperates with mandrel 1, and the projection 8 on the mandrel 1 then embeds the groove 11 on the elastomer 2;

Sealing ring 7 that is arranged on mandrel 1 two ends and abuts against with elastomer 2 and the baffle ring 6 that abuts against with sealing ring 7;

Be arranged on mandrel 1 end and be used for mandrel 1, rubber elastomer 2, sealing ring 7 and baffle ring 6 are connected fastening all-in-one-piece securing member 5, said securing member 5 can adopt conventional securing member such as bolt or pin;

One end of mandrel 1 is connected with power set 10.

Fig. 3 is another embodiment of the present utility model.As seen from Figure 3, the mandrel 1 of this embodiment has two projectioies 8, and other structures then structure with Fig. 1 are identical.Because mandrel 1 is provided with two projectioies 8, therefore between two projectioies 8, formed a recessed pool, when rubber elastomer 2 is under pressure along the chap of mandrel contraction weak point in the end, the pressure of recessed Tan Chu will be less than the pressure at other positions on the mandrel 1, play the effect of decompression, the pressure at protruding 8 places is then maximum, plays the effect of supercharging.

Fig. 4 is the mandrel schematic diagram with two monolateral angled protrusions 8.So-called " monolateral inclination ", one side be meant the not downward-sloping of projection 8, and be integrated with mandrel 1.Form a recessed pool between two monolateral protruding 8, when rubber elastomer 2 is under pressure along the chap of mandrel contraction weak point in the end, the pressure of recessed Tan Chu will play the effect of decompression less than the pressure at other positions on the mandrel 1.

Projection 8 on the mandrel 1 can be the part of mandrel 1, but as projection 8 is made an endless member, is enclosed within on the isodiametric mandrel 1, and then projection 8 can be separated with mandrel 1 dismounting, as shown in Figure 5.The use of the mandrel of this structure can be changed projection 8 according to the size of processed pipe fitting, and need not change other parts convenient.

Equally, rubber elastomer 2 also can combine by two, so that install and use.

Above-mentioned bloated head is performed such work:

Processed pipe 3 is enclosed within outside the elastomer 2, the tube sheet 4 that is provided with grooving 12 is enclosed within outside the pipe 3, starts power set 10, pulling mandrel 1, power set 10 apply external pressure F to the baffle ring 6 of mandrel 1 one ends simultaneously, make rubber elastomer 2 be subjected to axial compressive force, axially shorten, radially chap, force the pipes 3 that are enclosed within outside the rubber elastomer 2 that elastic-plastic deformations take place, realize bulging, thereby 4 applyings of the tube sheet of pipe 3 and outside make further tube sheet 4 that elastic-plastic deformations take place.After the unloading, pipe 3 and tube sheet 4 all can produce certain resilience, and when the resilience of pipe 3 during less than the resilience of tube sheet 4, both just combine.Simultaneously, pipe 3 can bulging protrude in the grooving 12 under the effect of pressure, plays the effect of strengthening bonding strength and improving sealing property; Traditional expanding joint process is in order to realize this protruding into, often improve whole expanded joint pressure, thereby cause the plastic deformation even the surrender of whole tube sheet, the unloading of the good tube-to-tube sheet connection joint that expanded around causing, joint around making leaks, and influences the expanded joint quality.

By above-mentioned disclosed technical scheme as seen, swollen head of the present utility model has fairly obvious advantage:

1. pressure regulation and one step of expanded joint are finished the production efficiency height;

2. simple in structure, science is convenient to implement;

3. owing to have the effect that increase and decrease is pressed, can prevent the tube sheet integral yield, reach the protection tube sheet, prevent Joint influences each other and produces the purpose of leakage;

4. can be used for connecting bellows or producing bellows;

5. require low to power set;

6. operating cost is low.

Claims

1. expanding head of tube expander with pressure increasing decreasing function, the securing member (5) that the baffle ring (6) that comprises mandrel (1), is enclosed within elastomer (2) on the mandrel (1), is arranged on mandrel (1) two ends and the sealing ring (7) that abuts against with elastomer (2), abuts against with sealing ring (7) and being used for links into an integrated entity mandrel (1), rubber elastomer (2), sealing ring (7) and baffle ring (6) is characterized in that:

Said mandrel (1) is provided with one or more projection (8);

Said elastomer (2) is provided with the groove (11) that matches with projection (8) on the mandrel (1), and the projection (8) on the mandrel (1) embeds the groove (11) on the elastomer (2).

2. expanding head of tube expander as claimed in claim 1 is characterized in that: the projection (8) that mandrel (1) is provided with is an one with mandrel (1).

3. expanding head of tube expander as claimed in claim 1 is characterized in that: the projection (8) that mandrel (1) is provided with is one to be enclosed within the parts on the mandrel (1).

4. as the arbitrary described expanding head of tube expander of claim 1～3, it is characterized in that: mandrel (1) is provided with the projection (8) of two monolateral inclinations.

5. as the arbitrary described expanding head of tube expander of claim 1～3, it is characterized in that: elastomer (2) combines by two.

6. expanding head of tube expander as claimed in claim 4 is characterized in that: elastomer (2) combines by two.