JPH02195093A - Circular-formed seal material to be used in pipe joint sealing method - Google Patents

Abstract

PURPOSE:To increase sealing property by making a circular-formed seal material in a specified form, in a pipe joint seal where a tightening ring, circular-formed seal material, retainer, pressure ring, and circular packing are placed on a pipe body for sealing. CONSTITUTION:In a sealing method of a pipe joint A which is forced into a clearance between a tightening ring D and a pipe body C to block and seal the clearance, the tightening ring D, circular-formed seal material B, retainer 10, pressure ring 11, and circular packing 12 are placed and tightened onto the pipe body C to press and deform the circular-formed seal material B. The formed body 5 constituting the circular-formed seal material B is made in such a specified external construction as, for example, bent largely, recessed, provided with a stopper, etc. Thus, the retainer can be prevented from being imvaded or bitten and good water-proof and corrosion-proof effect can be obtained.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to an annular molded sealing material used in a sealing method between a resin-lined packing type joint, particularly a mechanical pipe joint, and a pipe body connected thereto. This is related to the improvement of.

<Prior art> Waterproofing or corrosion protection of the connection between a pipe that transports fluids such as gas or liquid and a joint pipe that connects the pipes can be achieved by wrapping the outside of this part in a spiral shape with tape, or Methods such as covering the connector with a heat-shrinkable tube and shrinking it by heating, or tightening a rubber backing or an O-ring with a nut screwed onto the connecting portion are employed.

Modern pipe bodies often have a lining layer made of synthetic resin or the like formed on the surface of the steel pipe for the purpose of corrosion prevention, and mechanical joints are often used for the joints. The workability of covering with heat-shrinkable tubes is poor (currently, satisfactory results have not been obtained).

On the other hand, as a watertight method for sealing resin-lined packing-type pipe joints and pipe bodies, there is a method of sealing with packing inside the pipe joint, but the watertightness during bending and tensioning is insufficient.

Therefore, the present applicant has developed an annular molded sealing material filled with a semi-fluid sealing material that screws together a pipe and a fitting, and compresses and deforms the pipe and the fitting by tightening the annular molded sealing material. We previously proposed a method of sealing the gap by extruding it into the gap between the pipe and the pipe body (Japanese Patent Application No. 60-16).
No. 9563).

However, with the above method, the fastener may crush the annular molded sealing material when tightened, which may cause the position of the annular molded sealant to be moved, deformed, or damaged, and the sealant may not be filled properly. However, it is impossible to prevent water from entering from the outside and obtain a good corrosion protection effect.

Means for Solving the Problems> In view of the above, the present inventors have developed a method for sealing a pipe body and a pipe joint, in which the fastener is embedded in the annularly molded sealing material.
Alternatively, in order to prevent the annular molded sealing material from being destroyed, the present invention was developed as a result of studying the shape and material of the molded body used in the annular molded sealing material.

<Function> In the first place, the reasons why the fastener affects the annular molded sealing material are: (1) The molded material used for the annular molded sealing material is soft (However, if the molded material as a whole is made hard, the tightening Torque pressure increases,
I can not use it). (2) Since the fasteners are not fixed, they can easily move. ■The metal fastener crushes the molded object because the resistance at the contact area between the metal fastener and the molded object is too large. etc.

Therefore, we specified the shape of the molded object or changed part or all of the material to create a specified external structure, fixed the position of the fastener, and prevented the fastener from entering the molded object.
The purpose of this is to provide a molded body that protects the annular molded sealing material and does not impair its effectiveness as a suitable sealing material.

<Example> In order to join a pipe body and a pipe fitting using an annular molded sealing material using a molded body having a specific shape or a specific material according to the present invention, first, as shown in FIG. An internal thread 3 is carved on the inner periphery of the enlarged diameter portion 2 whose inner periphery is an inclined surface 1, and a tightening ring having a synthetic resin lining layer 4 formed on the entire outer periphery is inserted into the tube body C. Next, insert the annular molded sealing material B, the fastener lO1 holding ring 11, and the annular packing 12 in this order, and finally insert the pipe fitting A. Then, while rotating the tightening ring, the pipe fitting A is screwed together ( .

As a result, as shown in Fig. 3, as this bonding progresses, the annular molded sealing material B is compressively deformed, and the sealing material inside flows, filling the gap between the tightening ring and the tube body C. This prevents corrosion of the metal inside the joint.

In this case, the molded body 5 constituting the annular molded sealing material B has the shape or structure shown in FIGS. 1(a) to (g) in this invention. That is, in FIG. 1(a), the side of the molded body 5 in contact with the fastener 10 is thickened (curved) to match the shape of the fastener, and in FIG. Both of them have a shape in which the molded body 5 wraps around and fixes the fastener 10. In FIG. 1(c), the upper part of the molded body 5 has a shape that functions as a stopper. In FIGS. 1(d) and 1(e), the contact area between the fastener lO and the molded body 5 is made as small as possible (and this provides a sliding effect with the fastener 10).

In addition, FIGS. 1(f) and (g) show the contact surface of the 1° fastener of the molded body 5, or the contact surface and the upper part thereof, at an angle of 0.1 to 1,0
Intrusion of the fastener 10 is prevented by laminating or bonding 15 metal plates or synthetic resins such as high-density polyethylene resin, polypropylene resin, or polyester resin with a thickness of about 1.0 mm.

<Effects of the Invention> As explained above, the annular molded sealing material of the present invention has the following effects:
By specifying the shape of the molded body constituting the molded body, it is possible to prevent the fasteners from entering and biting into the molded body, thereby making it possible to form a joint having good waterproof and anticorrosion effects.

[Brief explanation of the drawing]

FIGS. 1(a) to (g) are explanatory diagrams showing the relationship between the specific shape and structure of the molded body constituting the annular molded sealing material of the present invention and the fasteners, and FIG. A vertical cross-sectional view showing the state in which the sealing method is implemented using
FIG. 3 is a longitudinal sectional view showing the state after implementation.

Claims (1)

[Claims] A tightening ring, an annular molded sealing material, a fastener, a presser ring, and an annular packing are externally inserted into the pipe body, and the end of the pipe body is inserted into the pipe joint, and the sealing material is deformed under pressure by screwing and connecting. In a pipe fitting sealing method in which the gap between the ring and the pipe is extruded to close and seal the gap, the molded body constituting the annular molded seal material has a specific external structure in order to prevent deformation and damage caused by the fastener. An annular molded sealing material used in the pipe joint sealing method.