JPS58191393A - Joints with fixed liner for lined piping system and its manufacture - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION BACKGROUND OF THE INVENTION The present invention relates to fittings for lined piping systems.
Ittings) More particularly, it relates to metal fittings lined with non-metallic materials intended for service, including in particular vacuum applications.

Metal pipes lined with non-metallic materials, usually thermoplastics, have been known for quite some time and are commonly used to process a variety of materials ranging from corrosive acids to food products. . One type of such pipe consists of a metal housing, usually of steel, lined with a layer of extruded thermoplastic resin. In general, the lining is of sufficient thickness and has a large diameter pipe cross section (5e
Even when exposed to high vacuum, the plastic is forced to withstand crushing stress (1ocked in 5 tres).
ses ) and can be economically produced. However, pipe fittings 1 such as cheese, etc.
When acting on cross and Y-type joints (wyes), single-branch openings weaken the liner so much and interrupt the annular cross-section that it becomes uneconomical to withstand crushing under the action of high vacuum. required.

The crushing by vacuum action of the liner is approximately 152+
It is particularly concerned with dog hook fittings of mn (6 inches) or soi''1.

In a somewhat related environment, ie, in the case of a squeezeable tube valve, resistance to vacuum is provided by securing the tube to the valve compressor member by means of interconnecting links.

Details of such an arrangement are referred to in my U.S. Pat. No. 3.79, issued February 12, 1974.
No. 1.617, and the same assignee as the present invention is hereby assigned.

SUMMARY OF THE INVENTION It is now possible to embed an anchor within the wall of a molded liner for a pipe fitting and to remove the externally protruding portion of the anchor without seriously degrading the plastic material.

It has been discovered that it is possible to fix it to the wall of the surrounding metal housing by welding.

According to one feature of the invention, of the molding material.

a metal housing lined with a non-metallic liner;
A piping system comprising at least one metal anchor having a first portion embedded and secured within said liner and a second portion protruding from said liner and welded to said housing. Is it a joint? (
J Emorelo.

In accordance with another feature of the invention, a first portion is molded from a non-metallic material and embedded within the non-metallic 4A region of the liner and protrudes from a radially outer surface of the liner. means for selecting a liner for said fitting having said second portion; and means for assembling parts of said housing around said liner; and a front portion having said liner fixed to said housing. A method is provided for assembling said joint, consisting of combining said parts Ii, (.) and means for welding said parts to said second part of said anchor to form a housing.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be better understood from the following detailed description of the present TLF preferred embodiment, taken in conjunction with the accompanying drawings. The same reference numerals are used throughout the drawings to refer to the same or similar parts.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference should now be made to FIG. 1, which illustrates a reducing cheese 10 embodying the present invention. In this example (
・The cheese joint 10 has a joint size of 1. Continuation stub end (run 5tub
ends) 11 and 12 as well as the stub ends 16 of the vertical tube, and are formed from vancouston flanges 16, 1
It has a metal housing given numbers 7 and 18.

The housing of the fitting 10 is made of a molded non-metallic material, i.e. 1sostatically molded.
molded) polytetrafluoroethylene (PTF'E)
) liner 19. As shown in the figure, the continuous end of the liner 19 and the end of the upright tube extend outwardly from the stub ends 11-15 and extend radially over the flange surface formed on the stub ends. Open outward in the direction.

If a fitting such as that just described with respect to FIG. For example, the liner 19 generally has a constriction extending parallel to a plane containing the seam 14 and the longitudinal axis of the vertical stub end 13, forming an imaginary circle 2.
1 within the range indicated by 0. or will have a tendency to shrink. However, the structure described below prevents such damage.

Referring to FIG. 2, the liner 19 is shown here before being assembled within its metal housing, +1. Te(・ru.

The liner 19, which is at a 1° angle to the cheese joint, intersects at the joining line 26--leaving the subsequent part 21 and the vertical part 22.

The length of each part of the liner 19 is as shown in Figure 1.
It must be sufficiently long to allow for radially outward opening (44).

Regarding the continuous parts 21, the nine parts are located on a plane passing through the longitudinal axis of the part 21 and perpendicular to the longitudinal axis of the vertical tube part 22. Points forming two diameters (one point 24
A metal anchor 25 made as shown in FIG. 4 is embedded in each of the holes (only one of which is visible in FIG. 2). The anchor 25 consists of an extra root 26 and a metal stud 27, the latter being joined to the plate 26 by welding. The board 2
6 is provided with a series of openings or holes 28.

The dimensions of anchor 250 and its relative position within the wall of liner 19 are best seen in FIG.
Ru. - the castarad 27 projects outside and above the radial outer surface of the liner 190; Note that the exposed portion of the stud 27 is joined by welding to the surrounding metal housing once assembled with the metal housing, so that one dimension A is included when the liner 19 is subjected to a vacuum action. Anchor 2
The minimum thickness must be selected to provide adequate strength to withstand pull-out of 5. The thickness C of the plate is such that when high vacuum stress is applied to the inner 19, the plate 26
It must provide sufficient mechanical strength to withstand bending. The measured thickness is determined by the expected service requirements for corrosion resistance, erosion resistance, abrasion resistance, and the like. Dimension B
is A.

It is a function of the cumulative requirements for C as well as D.

Under vacuum action, the stud 27 is placed in tension and the hole is
Its diameter is selected to resist rupture under such conditions. The length of stud 27 will be discussed later.

Holes 28 are provided in plate 26 to ensure that the plastic of liner 19 is bonded to anchor 25 and that the radially inner and outer layers 29 and 30 of plate 26 are joined together. The shape of the plate 26 can be varied as desired so long as it fulfills the function ascribed to it.

The cheese joint 10 of FIG. 1 has a liner 19 selected,
Each franc 16, 17 and 18? the corresponding pre-installed stub ends 11, 12 and 13;
It is created by assembling the continuation part and the vertical tube part. The stub end 11゜12 parallel 1
It will be appreciated that each 6 is preformed with a flange or flare at one end and a weld bevel or conventional chamfered or beveled edge at the other end. However, departing from conventional practice.

The welding groove of Stub En F11 and 12 is as follows.

As best seen in FIG. 5, the anchor is provided with a notch, preferably cylindrical, in a suitable complementary position for accommodating the protrusion of the stud 27 within the welding area.

Referring to FIG. 5, there is shown here a weld bevel 61 of the continued stub end 12 of the housing having a face 32 perpendicular to the longitudinal axis of the stub end 12 as well as a bevel face 3. . The groove 31 is formed with a notch 54 that cooperates with a complementary notch (not shown) in the stub end 11 to accommodate the stud 27 71. Ru. It should be appreciated that the stud 27 should be of sufficient length to protrude into the V-shaped section which will be filled with weld metal during the welding operation and will contain the molten metal build-up. The top of the stud 270 is below the outer diameter of the metal housing.

However, the groove line (break / r
71e). If the weld is not properly cut, it should generally look like the one shown in FIG. No. If it penetrates too close to the inner diameter of the metal housing, it will cause liner 190 quality degradation. For example, if the liner is made of I) TFE, the resin will undergo overheating and scum.

The joints were assembled as described above using the stub end of the carbon steel housing with the anchor 25 made of stainless steel. Successful welds were made using metal inert gas welding equipment.

For small diameter fittings with branch pipes not larger than approximately 152 rMl (6 inches) and thicker (and where the branch pipes are not thicker than approximately 205 mm (8 inches), they should be placed as described in F. It is believed that two anchors are sufficient: a 1/2 inch diameter stand and a run.
Nitsu(・teha.

It may be necessary to include an anchor with an additional stud located at the intersection of seams 14 and 15 in FIG.

The present invention is limited to reducing cheese joints71. No, but standard cheese as shown in Figure 7 as well as the one shown in Figure 8?
'L' is equally useful for standard form crosses.

Referring to FIG. 7, the standard cheese has a metal housing formed from continuous stub ends 41 and 42 and a vertical stub end 46 joined by seam welds 44 and 45. . Joints 44 and 45 intersect at point 46 on the side of the joint visible in the drawing as well as at a similar point not visible on the opposite side of the joint. Then weld inside the seam.

and the stud 27 of the other anchor is similarly welded into the joint at a point opposite L. The liner 49 of the joint of FIG. It consists of a part with a uniform diameter and a part with a vertical tube.
-ru. In all other respects, the coupling of FIG. 7 is similar to that described with reference to FIG.

In FIG. 8, a cross joint 50 is shown assembled similar to the cheese joint described above.

Preferably, the two anchors are each 71. so that its studs coincide with the intersection of the seam welds represented by points 52 in the figure. One liner 51 will be installed on each side of the liner. The second point is exactly the opposite.

- The liner of the joint is molded in an equilibrium state. This method is suitable for resins such as P T F E because the liner in the joint is molded in an equilibrium state.
This is because the cost of raw materials for molding (olding) is less than that cost for extrusion.

Another advantage of equilibrium molding is that the method produces liners that better fit into their respective housings. Generally, such methods are more economical.

The use of the anchors described herein allows the use of thin liner thicknesses and ensures structural integrity under the action of high vacuum.

""BD, PVDF, PFA and PP (fluorinated ethylene propylene, polyvinyritine fluoride.

Plastics other than PTFE, such as perfluoro-7) 1-koxy and polypropylene, can also be used to make liners for joints with anchors, such as those described herein.

Having described the invention in connection with its preferred embodiment, various changes in construction and detail may be incorporated therein without departing from the true spirit of the invention as defined in the appended claims. It must be clear what you want to get.1.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional elevational view of a reducing tube embodying the invention; FIG. 6 is a perspective view of the liner. FIG. 6 is a line 6--6 of FIG. 2 showing details of the metal anchor.
FIG. 4 is a perspective view of the metal anchor in a circumferential cross-section taken along the line; FIG. A fragmentary view of the stud portion of the anchor: FIG. 6 is a view similar to FIG. 5, but after the welding operation. FIG. 7 is a perspective view of a standard cheese embodying one invention; and FIG. 8 is a perspective view of a cloth embodying one invention. [Explanation of symbols of main parts]

Claims (1)

Claims: 1. A metal housing lined with a non-metallic liner of molded material, a first portion embedded and secured within the liner, and a first portion protruding from the liner and welded to the housing. 1. A fitting for a lined piping system, characterized in that the fitting comprises at least one metal anchor having a second portion. 2. Claim 1, characterized in that the housing contains parts joined by welded seams, and the second part of the anchor is welded into one of the seams. Fittings by section. 6. Joint according to claim 2, characterized in that the molded material is a thermoplastic. 4. Joint according to claim 1, characterized in that the molded material is a thermoplastic. 5. Said housing is formed from two parts, at least one continuation part, said parts being joined together to form two substantially diametrically small (both substantially diametric) a welded seam with said housing having said parts joined to each other at a point (), and at another point at which two of said anchors make said diameter (
6. A joint according to claim 2, characterized in that the housing has a respective second part, each of which is welded into the seam, and is secured within the liner.6. A joint according to claim 5, characterized in that it is in the form of a joint selected from the group consisting of a cheese, a cross and a Y-shape. 7. A liner molded of a non-metallic material; Selecting a liner of the fitting having at least one anchor embedded in the non-metallic material and having at least one anchor embedded in the first portion as well as the second portion protruding from the radially outer surface of the liner; Assembling parts of a Pino lambda housing around the liner and welding the parts to each other and to the second part of the anchor to form the housing with the liner secured to the housing. 8. A method for manufacturing a joint according to claim 1, characterized in that: 8- two said anchors arranged in substantially I-diametric positions on opposite sides of a continuous channel; a part of the housing is assembled around the liner with the second portion of the anchor disposed between facing grooves of the housing part; 8. A method according to claim 7, characterized in that the grooves are welded to each other and to the second part of the anchor.