CN1182179A

CN1182179A - Sealing method for sleeved hydraulic pipe joint

Info

Publication number: CN1182179A
Application number: CN 97109816
Authority: CN
Inventors: 孔繁梅; 汪荣丽
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-04-23
Filing date: 1997-04-23
Publication date: 1998-05-20
Anticipated expiration: 2017-04-23
Also published as: CN1065331C

Abstract

The present invention is suitable for sealed connection of pipeline in hydraulic system. On the basis of available sleeve pipe joints, the nut, sleeve and joint body are heat traeated, so that the hardness of sleeve is smaller than that of nut and joint body but greater than pipe end. The front edge of sleeve is provided with sealing ring and conic shaft with conic sleeve is provided. During installation, the conic shaft with conic sleeve is first pushed into pipe end and sleeve and nut are fit, and after the joint body is fitted and the edge of sleeve is pushed into pipe end, the conic shaft is demounted.

Description

The encapsulating method that is used for sleeved hydraulic pipe joint

The present invention relates to a kind of encapsulating method that is used for sleeved hydraulic pipe joint, be applicable to the high, medium and low connection of depressing pipeline in the hydraulic system of machinery.

The quality of equipment leakage problems pipe joint was crucial in the past.Sleeved hydraulic pipe joint originally is made up of cutting ferrule nut connector body, not cutting ferrule card not tight, and tube drawing easily, the pressure effect of cutting ferrule makes pipe easily shrink bending, and promptly influencing rigidity has resistance to liquid stream again.Only be that the contact seal of dependence stiff dough is not tight, be in vibrational state especially for a long time, temperature often changes again, impels surface of contact easier to be loosening, leaks heavy more often more.Easily install because its cost simple in structure is low, so China's machinery, especially machine tool generally use it for many years.Again because its said structure feature, so its leakage problems never solves, and becomes nationwide hard nut to crack.Looked round the new large-scale production automatic control line of installing of certain factory in the recent period, found almost whole seepages of all pipe joints, all be provided with oil trap below every equipment, on the about ground of groove and the oil of seepage is all arranged on the pipe, problem is serious.

In view of above-mentioned existing problem, the purpose of this invention is to provide a kind of encapsulating method that makes the sleeved hydraulic pipe joint of pipeline ne-leakage, and have the performance that is difficult for tube drawing.

The objective of the invention is to realize by following technological scheme:

At first the pipe joint member of cutting ferrule, nut, fittings body is all heat-treated, method can be undertaken by relative national standards, and the surface hardness that guarantees to make cutting ferrule will be lower than nut and fittings body greater than pipe.Manufacturing a diminished shaft 4 these parts with common iron processing then is a taper, and butt end is established a horizontal through hole 5 and prepared against its usefulness of extracting from pipe.Thin end is also established a horizontal pin through hole 1, and a close-fitting pin 1 is installed in the hole, and its both ends of the surface must not exceed the external diameter of axle sleeve, can not be lower than the internal diameter of axle sleeve, so that axle sleeve can not leave diminished shaft.Tapered hub 3 Spielpassung with tapering are overlapped at the middle part of diminished shaft, and its axial jacket wall has one to disconnect groove 2, so that axle sleeve can change diameter.Above diminished shaft and tapered hub can be equipped with a plurality of special purpose parts according to the different-diameter of various pipes, and heat-treat to strengthen rigidity and surface abrasion resistance.The pipe end face should be processed into smooth smooth, and vertical with tube's axis, internal orifice fall shuttle should with groove 11 shape complementarities.Diminished shaft and tapered hub only can be standby for a long time otherwise damage.

Before cutting ferrule 8 is installed, earlier the thin end of tapered hub is suppressed in the mouth of pipe, must not be higher than the pipe end face will align with the mouth of pipe, diminished shaft 4 is squeezed in pipe again, makes it fastening not loosening.If pipe not circle can firmly be suppressed again and makes till its fourth contact.To refill upper cap nut 9 and cutting ferrule 8 on the pipe 7 then, pipe end is inserted exert oneself in the fittings body 10 with the nut handle tightly two road cutting ferrule cutting edges 12 are all snapped in the tube wall, till outward appearance is seamless again.Under the inexperienced situation of first operation, must check like this, after being arranged, experience to spot-check.And then unload and take out diminished shaft 4, on the position of cutting ferrule chucking, have other sealing material (as the sealer class) of toughness and flexible strong adhesion again tightly both can after putting oil resistant rubber seal ring 6 or also can coating curing again.Perhaps add oil resistant rubber sealing gasket or sealer silicon sealant and so at groove 11.The oiling agent that will should be coated with the anti-extreme pressure of last layer on the inclined-plane attrition surface of nut and screw thread and fittings body in advance is as molybdenum disulfide, graphite etc.Groove 11 should be processed in the place that contacts with pipe end on fittings body in addition, and pipe end face internal diameter is answered chamfered edge, and shape and groove 11 complementations are with the contraction deformation of avoiding pipe and the rigidity of reinforced pipe.

The present invention compared with the prior art, between each assembly parts, the surface hardness of cutting ferrule is greater than pipe and be lower than nut and fittings body, the distribution of hardness has not only guaranteed the dark of cutting ferrule two road cutting edge cards like this, tight, good seal, and improved the working life and the wear resistance of fittings body and nut, through loading and unloading repeatedly also chamfered edge not.Increase the anti-extreme pressure oiling agent again and also significantly reduce friction, most power is used on the chucking of cutting ferrule two road cutting edges and makes the darker of its card.Two road cutting edges 12 of cutting ferrule used to stick into together, and present two road cutting edges stick into entirely and do not stay the slit in the tube wall.The interaction energy of diminished shaft keeps the pipe rigidity, has avoided the consumption in power pipe elasticity and the plastic deformation.Ropy in addition pipe out of roundness is very big, and the cutting ferrule pipe joint can not be used, and diminished shaft can make its fourth contact, has satisfied quality requirement.Pure rigid sealing is insecure, because it is subjected to multiple factor affecting, the degree of workpiece surface finish contact and rising-heat contracting-cold and impact etc. all easily make surface of contact become flexible and produce seepage.Add a soft elastic material on the key position of this cutting ferrule chucking, increased the deficiency that an elastic soft sealing has remedied hard sealing again, make the sealing more closely reliable, this elastic material has been blocked all three roads that liquid may pass through.Groove 11 has increased pipe end rigidity, reduces the rigidity that distortion has also strengthened whole pipe joint, has also avoided the resistance that liquid is produced because of pipe end shrink mouth.Facts have proved the pipe joint ne-leakage of this device, pipe is undergauge not, tube drawing not, and long service life thoroughly solves the long-term seepage of sleeved hydraulic pipe joint, short big old difficult problem of tube drawing oil spout and working life occurs.

Fig. 1 is a sleeved hydraulic pipe joint structural representation of the present invention.

Fig. 2 is the schematic representation of cutting ferrule two road cutting edges of the present invention and fittings body upper groove and sealing material position.

1--carefully holds pin-and-hole, 2--tapered hub opening, 3--tapered hub, 4--diminished shaft, the horizontal through hole of 5--diminished shaft butt end, 6--oil resistant rubber seal ring, 7--tube head, 8--cutting ferrule, 9--nut, 10, fittings body, 11-fittings body groove, 12--cutting ferrule two road junctions.

Specifically describe embodiments of the invention below in conjunction with accompanying drawing:

For example to a kind of external diameter Φ 28mm, internal diameter 24mm of pipeline, wall thickness 2mm, the end face filing also makes it smooth smooth vertical with tube's axis, the internal diameter chamfered edge, oil resistant rubber seal ring external diameter Φ 22mm, diameter of phi 1.5mm, anti-extreme pressure oiling agent are its shape and groove 11 complementations behind the molybdenum disulfide pulvis tube head chamfered edge.Each parts material of pipe joint and heat treatment method are the same with NBS.Hardness profile: cutting ferrule 8 surfaces are HV500, fittings body and nut surface HV800.And with molybdenum disulfide pulvis on inclined-plane in the fittings body and nut inner thread and the coated on bottom side.Diminished shaft butt end Ф 22mm has a Φ 5mm hole apart from end face 5mm, and oil end Φ 18mm has a Φ 5mm hole apart from end face 5mm place, in adorn one and the long 23mm of the friction tight pin in hole.Taper axial length 77mm, a tapered hub is adorned at the middle part, and tapering is identical with axle, the external diameter Φ 24mm of butt end, internal diameter Φ 20mm axially opens a wide 2mm of mouth.

Operating process:

It is vertical with tube's axis that Φ 28mm wall thickness 2mm is managed the whole polishing of an end face filing, end face internal orifice chamfered edge and groove 11 complementary dimensioned, load onto nut and cutting ferrule successively, refill the epicone oblique crank Z, axle sleeve will flush with the pipe end face, suppress diminished shaft more inwards, tube opening and tapered hub are tightly contacted firmly, refill the upper connection body, nut is exerted oneself tight with removing son, (tight degree being wanted two road cutting edges of cutting ferrule are sticked in the tube wall entirely, till outward appearance is seamless).Take off pipe again and unload diminished shaft, again the oil resistant rubber seal ring is enclosed within the outside of cutting ferrule cutting edge chucking, refill in fittings body,, unload inspection oil resistant rubber seal ring and should not have breakage with removing son tight, and the cutting ferrule cutting edge should to stick into tube wall entirely seamless.

Reach 60MPa through product quality supervision and testing institute test result Φ 28 specifications, do not take place to leak and the structural failure situation in 20 minutes.

Claims

1, the encapsulating method that is used for sleeved hydraulic pipe joint, comprise the nut (9) of pipe joint, cutting ferrule (8), fittings body (10) with cutting edge, it is characterized in that between tube head (7) outer wall in the forward position of cutting ferrule (8) cutting edge and fittings body (10), elasticity oil resistant rubber seal ring being housed the contacting of the chamfering complementation at the bottom of the groove of tube head mouth (7) internal diameter chamfering and fittings body (10); Have a diminished shaft (4), its butt end has horizontal through hole (5), thin end has horizontal through hole and has pin (1) to closely cooperate, diminished shaft (4) is with the axle sleeve (3) with its Spielpassung outward, and diminished shaft (4) carefully holds pin (1) the biend length of horizontal through hole must not be greater than the internal diameter of tapered hub above the tapered hub external diameter; Tapered hub (3) wall has the mouth (2) of axial disconnection; Nut, cutting ferrule, fittings body will heat-treat (connecing national standard method), will make cutting ferrule (8) surface hardness greater than the hardness of having managed and less than the hardness of nut and fittings body; Before molybdenum disulfide or graphite lubricant are coated in the inclined-plane of nut internal surface and fittings body at installation cutting ferrule (8), earlier the thin end of tapered hub (3) is suppressed in the mouth of pipe and alignd with the mouth of pipe, diminished shaft (4) being squeezed in pipe makes it fastening motionless again, again pipe end is inserted in the fittings body (10) and firmly make the cutting edge on its cutting ferrule all be pressed in the tube wall nut tightening loading onto nut (9) and cutting ferrule (8) on the pipe (7) then, and then take off diminished shaft (4), put the sealing material that has toughness and flexible strong adhesion after oil resistant rubber seal ring (6) maybe can be coated curing at the position of cutting ferrule chucking again, after tighten again.

2, by the described method of claim 1, it is characterized in that between fittings body inner groovy (11) bottom surface and tube head (7), the oil resistant rubber sealing gasket being housed.