JPH0587287A - Silica tube joint - Google Patents

Abstract

PURPOSE:To provide the slip-stop effect of a silica tube and a coupling function excellent in safety and reliability by deforming a clamping ring into diametral contraction, while fitting a slip-stop ring tight in an outer circumferential peripheral groove of the silica tube, and holding this slip-stop ring in space between opposed surfaces of a lock nut and the clamping ring. CONSTITUTION:An end 3a of a silica tube 3 is inserted into one end side connecting part 2a of a joint body 2 and then this connecting part 2a of the joint body 2 is screwed in a lock nut 4 fitted on an outer circumferential surface of the silica tube 3. In succession, each opposed surface between the one end side connecting part 2a of the joint body 2, a slip-stop ring 5 fitted tight on an outer circumferential surface of the silica tube 3 and a clamping ring 6 fitted on the outer circumferential surface of the silica tube 3 is clamped in direction of being pressure-contacted, through which the one end side connecting part 2a of the joint body 2 and the end 3a of the silica tube 3 are interconnected in airtightness. With this constitution, not only a leakage of conveying fluid is surely prevented but also connection of silica tubes themselves and/or connection between the silica tube and other pipe members are easily performable, thus improvement of working properties is well promoted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a quartz pipe joint used, for example, for connecting a quartz tank for cleaning a silicon wafer and a chemical liquid supply system, or for a chemical liquid supply system in a semiconductor manufacturing line.

[0002]

2. Description of the Related Art Conventionally, as a pipe joint used in a chemical liquid supply system such as the above example, for example, as shown in FIG.
-54599 gazette). This pipe joint 30
After the tightening ring 32 and the tightening nut 33 are sequentially fitted on the outer peripheral surface of the synthetic resin tube 31, the end portion 31 a of the synthetic resin tube 31 is connected to the one end side connecting portion 3 of the joint body 34.
4A, and the tightening nut 33 fitted on the outer peripheral surface of the synthetic resin tube 31 and the joint body 34 are screwed together. After this, the tapered surface 34b formed on the joint body 34
And the taper surface 32a formed on the tightening ring 32 are pressed to rotate the tightening nut 33, so that the tightening ring 32 is radially contracted and deformed against the material elasticity.
This is a pipe joint 30 in which the same tightening ring 32 is cut into the outer peripheral surface of the synthetic resin tube 31 to prevent it from being pulled out and fixed.

[0003]

However, in the pipe joint 30 as described above, when the fluid pressure applied during use becomes higher than the limit, the biting portion of the synthetic resin tube 31 is deformed and easily comes out, and thus the pipe joint 30 is used. When the fluid temperature rises even if the fluid pressure applied at times is below the limit, the bite portion of the synthetic resin tube 31 is softened and easily comes out.
In addition, the larger the diameter of the synthetic resin tube 31 is, the more the stress relaxation occurring in the bite portion becomes remarkable, and the range of use thereof is limited.

As a means for solving the above-mentioned stress relaxation, for example, a quartz tube (not shown) made of a material which is not easily affected by the pressure change and the high temperature change of the fluid may be used. One end side connection portion 34a of the joint body 34
After forcing the tightening nut 33 to rotate with a jig such as a wrench, the quartz tube hardly undergoes diameter reduction deformation, and as a tube joint for connecting the quartz tube, the retaining force is high. However, a pipe fitting with excellent safety and reliability has not been developed.

In view of the above problems, the present invention is such that a tightening ring is reduced in diameter on the outer peripheral surface of a quartz tube and fixed by pressure, and a retaining ring is fitted and fixed in a peripheral groove formed on the outer peripheral surface of the quartz tube. It is an object of the present invention to provide a quartz pipe joint in which the quartz pipe and other pipe members can be firmly connected to each other by fixing and preventing the joint, and a joint function with high safety and reliability can be obtained.

[0006]

According to the present invention, an end portion of a quartz tube is inserted into a connecting portion on one end side of a joint body, and a tightening nut inserted on the outer peripheral surface of the quartz tube and one end side connection of the joint body. The end portion of the tightening nut and the taper surface formed on the one end side connecting portion of the joint main body, and the tightening is performed in the direction in which the outer peripheral surface of the quartz tube is crimped and fixed. The retaining ring is reduced in diameter and fixed, and the retaining ring is fitted and fixed in the circumferential groove formed on the outer peripheral surface of the quartz tube, and the retaining ring is tightened with the tightening nut inserted into the quartz tube. It is characterized in that it is a quartz pipe joint held between the surfaces facing the attached ring.

[0007]

According to the present invention, since the end portion of the quartz tube is inserted into the one end side connecting portion of the joint body, the tightening ring is deformed by reducing the diameter on the outer peripheral surface of the quartz tube and fixed by pressure. Not only the leakage of the transport fluid is reliably prevented, but also, for example, the quartz pipe and the quartz pipe or the quartz pipe and other pipe members can be easily connected, and the workability can be improved. .. Moreover, since the retaining ring is fitted and fixed in the circumferential groove engraved on the outer peripheral surface of the quartz tube to secure the retaining force, a high retaining force exceeding the breaking limit of the quartz tube itself is obtained and the sealing function is not impaired. As it is a material that is highly safe and reliable and has a high joint function and is not easily adversely affected by changes in fluid pressure and temperature, the maximum operating temperature and pressure are significantly improved, making it a pipe joint. The range of application can be expanded.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The drawings show a quartz pipe joint of a first embodiment used for connecting a quartz pipe and a synthetic resin tube. In FIGS. 1 and 2, the quartz pipe joint 1 has a cylindrical shape. After inserting the end portion 3a of the quartz tube 3 into the one end side connecting portion 2a of the formed joint body 2, the one end side connecting portion 2a of the joint body 2 is inserted.
And a retaining nut 5 fitted and fixed on the outer peripheral surface of the quartz tube 3 and the one end side connecting portion 2a of the joint body 2 by screwing together a tightening nut 4 fitted on the outer peripheral surface of the quartz tube 3. Tighten in a direction in which the surface opposite to the tightening ring 6 inserted into the outer peripheral surface of the quartz tube 3 is pressed, and one end side connecting portion 2a of the joint body 2 and the end portion 3a of the quartz tube 3 are connected in an airtight state. To do.

On the other hand, P is attached to the connecting portion 2b on the other end side of the joint body 2.
After the end portion 7a of the synthetic resin tube 7 formed of a synthetic resin such as FA is fitted and inserted on the outer peripheral surface of the sleeve 8, the other end side connecting portion 2b of the joint body 2 and the synthetic resin tube 7 are joined together. The tightening nut 9 inserted into the outer peripheral surface is screwed into the joint body 2, and the other end side connecting portion 2b of the joint body 2 is tightened in a direction in which the opposing surfaces of the synthetic resin tube 7 and the sleeve 8 are pressed together. The other end side connecting portion 2b of 2 and the end portion 7a of the synthetic resin tube 7 are connected in an airtight state.

Each of the elements 2, 4, 5, 6, 8 and 9 constituting the above quartz pipe joint 1 has chemical resistance and heat resistance for transporting chemicals such as strong acid and strong alkali. The joint body 2 and the tightening ring 6 are made of a synthetic resin such as PTFE or PFA, which are made of a resin material having excellent pressure resistance, and the tightening nuts 4, 9 are made of a synthetic resin such as PFA or PP.
The retaining ring 5 and the sleeve 8 are formed respectively.

In the joint body 2 described above, an insert recess 10 having a shape and size that matches the end 3a of the quartz tube 3 is formed in the connection portion 2a on one end side of the joint body 2, and the inner peripheral edge of the insert recess 10 is formed. A male screw portion 1 is formed which has a conical tapered surface 10a having a small diameter toward the direction of inserting the quartz tube 3 and is screwed onto the female screw portion 4a of the tightening nut 4 on the outer peripheral surface of the same-side connecting portion 2a.
0b is threaded. Moreover, the end portion 7a of the synthetic resin tube 7 and the sleeve 8 are connected to the other end side connection portion 2b of the joint body 2.
And a conical taper surface 11a having a smaller diameter toward the inserting direction of the synthetic resin tube 7 is formed on the inner peripheral edge of the insertion concave portion 11, and the same side connection portion is formed. On the outer peripheral surface of 2b, a male screw portion 11b to be screwed with the female screw portion 9a of the tightening nut 9 is threaded.

The above-mentioned tightening nut 4 is formed by threading a female screw portion 4a on the inner peripheral surface of the tightening nut 4 and inserting the tightening nut 4 into the center of the tightening nut 4 with a diameter slightly larger than the outer diameter of the quartz tube 3. A hole 4b is formed, and a step portion 4c that abuts the rear end surface of the retaining ring 5 is formed on the inner peripheral edge portion of the insertion hole 4b.

The retaining ring 5 has a through hole 5a formed in the central portion of the retaining ring 5 and having a shape and size that matches the peripheral groove 3b formed on the outer peripheral surface of the quartz tube 3 to prevent the retaining ring 5 from retaining. The outer peripheral portion on one end side of the ring 5 is radially cut to form a dividing groove 5b, and the outer peripheral portion on the other end side of the retaining ring 5 is partially cut away to form a connecting portion 5c. That is, the quartz tube 3
When the retaining ring 5 is fitted on the outer peripheral surface of the, the connecting portion 5c of the retaining ring 5 is slightly bent against the material elasticity,
The insertion hole 5a of the retaining ring 5 having a diameter slightly larger than the outer diameter of the quartz tube 3 is inserted in a state of being radially expanded and deformed.

The above-mentioned tightening ring 6 has a through hole 6a having a diameter slightly smaller than the outer diameter of the quartz tube 3 formed at the center of the tightening ring 6, and the quartz tube 3 is formed on one end surface of the tightening ring 6. Conical taper surface 6 with a smaller diameter toward the insertion direction
b is formed, and the tapered surface 6b is formed to have a shape and dimension that match the tapered surface 10a formed on the one end side connecting portion 2a of the joint body 2 described above.

Assuming that the illustrated embodiment is configured as described above, a method of connecting the quartz tube 3 and the synthetic resin tube 7 by the quartz tube joint 1 will be described below. First, as shown in FIGS. 1 and 2, a tightening nut 4 is inserted on the outer peripheral surface of the quartz tube 3 and tightened rearward of a peripheral groove 3b formed on the outer peripheral surface of the quartz tube 3. After moving the nut 4, the quartz tube 3
The retaining ring 5 is radially expanded and deformed and fitted on the outer peripheral surface of the. That is, the connecting portion 5c of the retaining ring 5 is slightly bent against the elasticity of the material, and the insertion hole 5a of the retaining ring 5 is inserted.
Is inserted into the quartz tube 3 while being expanded and deformed to a diameter slightly larger than the outer diameter of the quartz tube 3, and the retaining ring 5 is fitted and fixed in the circumferential groove 3b formed on the outer peripheral surface of the quartz tube 3. To do.

Next, the tightening ring 6 is fitted on the outer peripheral surface of the quartz tube 3 and is moved to a position where it comes into contact with the retaining ring 5 fitted and fixed on the outer peripheral surface of the quartz tube 3. After that, the end portion 3a of the quartz tube 3 is inserted into the insertion recess 10 formed in the one end side connecting portion 2a of the joint main body 2, and the tapered surface 10a formed in the one end side connecting portion 2a of the joint main body 2,
The quartz tube 3 is deeply inserted to the position where the tapered surface 6b formed on the tightening ring 6 contacts. After that, the tightening nut 4 fitted on the outer peripheral surface of the quartz tube 3 is screwed into the one end side connecting portion 2a of the joint main body 2, and the one end side connecting portion 2a of the joint main body 2 is screwed.
The tightening nut 4 is manually rotated in a direction in which the taper surface 10a formed on the upper surface and the taper surface 6b formed on the tightening ring 6 are pressed against each other. Then, the other end side connecting portion 2b of the joint body 2 and the end portion 3a of the quartz tube 3 are connected to each other in an airtight state by communication.

That is, the step portion 4c of the tightening nut 4 is pressed against the retaining ring 5, and the end faces of the retaining ring 5 and the tightening ring 6 on the opposite side are pressure contacted with each other to the one end side connecting portion 2a of the joint body 2. Formed taper surface 10a and tightening ring 6
By making pressure contact with the taper surface 6b formed in, the tightening ring 6 is forcibly contracted and deformed against the material elasticity.
The tightening ring 6 can be crimped and fixed on the outer peripheral surface of the quartz tube 3.

On the other hand, after the end portion 7a of the synthetic resin tube 7 is fitted on the outer peripheral surface of the sleeve 8 and inserted into the other end side connecting portion 2b of the joint body 2, the other end side connection of the joint body 2 is made. Part 2b
A tightening nut 9 inserted into the outer peripheral surface of the synthetic resin tube 7 is screwed into the socket, and the insertion recess 11 formed in the other end side connecting portion 2b of the joint body 2 and the synthetic resin tube 7 and the sleeve 8 face each other. The tightening nut 9 is manually rotated in the direction in which the surfaces are pressed against each other, and the tightening nut 9 is rotated a specified number of times with a spanner or the like from the time when the tightening nut 9 cannot be tightened by hand as described above, and the tightening is fixed. The other end side connecting portion 2b of 2 and the end portion 7a of the synthetic resin tube 7 are connected in an airtight state.

As a test method of the above quartz pipe joint 1,
For example, a sample No. used for connection with a tube diameter of 19 mm. 1 to
NO. 4 and the sample No. used for connecting the pipe diameter 8 mm. 5
~ NO. A heat cycle test was conducted in a state where the screws 8 and 8 were tightened by hand and then tightened 1/2 turn with a spanner or the like.

These sample NO. 1-NO. 8 is subjected to a heat cycle test, as shown in FIG. 3, one end side of the test path 13 constituting the heat cycle test apparatus 12 is connected to the oil supply path 1
4, the other end of the test path 13 is connected to the middle part of the oil recovery path 15, and the thermometer 16 and the pressure gauge 17 are connected to the oil recovery side of the test path 13. .. On the other hand, one end of the oil supply passage 14 is connected to the supply pump 18
And the outlet side of the high temperature tank 20 via the switching valve 19, and the other end of the oil supply passage 14 is connected to the supply pump 21.
Also, it is connected to the outlet side of the low temperature tank 23 via the switching valve 22. Moreover, one end side of the oil recovery passage 15 is connected to the inlet side of the high temperature tank 20 via the switching valve 24,
The other end of the oil recovery passage 15 is connected to the inlet side of the low temperature tank 23 via a switching valve 25.

As shown in FIG. 4, in the test passage 13 described above, the sample No. 1 was provided on the oil supply passage 14 side through the synthetic resin tube 7 and the quartz tube 3. 1-NO. Connect 4 and hand tighten, then tighten 1/2 turn with a spanner etc. On the other hand, on the oil recovery path 15 side, the sample NO. 5 to NO. Connect 8 and tighten by hand, then tighten 1/2 turn with a spanner. Moreover, the sample NO. 4 and sample No. 4 on the oil recovery side. 5 are connected via a synthetic resin tube 7 and a metal tube 26 made of SUS, and each synthetic resin tube 7 ... 1 to N
O. 8 are connected to the tube connecting portions 27, and the quartz tubes 3 ... 1-NO. 8 are connected to the quartz tube connecting portions 28, respectively.

As described above, the sample NO. 1-NO. After piping 8, switching valves 19 and 2 installed on the high temperature oil supply side
4 and switching valves 22, 2 provided on the low temperature oil supply side
5 and 5 are alternately opened and closed, and as shown in FIG. 5, silicon oil of about 200 ° C. stored in the high temperature tank 20 and
The normal temperature silicone oil stored in the low temperature tank 23 is alternately circulated and supplied every hour, and this cycle is defined as one cycle (2 hours), and is repeatedly circulated for 100 cycles at the time of the test. Piping sample No. 1 to N
O. Test 8 performance.

That is, silicon oil (KF968) was used as the test transport fluid, the hydraulic pressure during high temperature oil supply and low temperature oil supply was set to 1 kg / cm ² , and the tank outlet temperature during high temperature oil supply was 196. ℃ (measured temperature), set the tank outlet temperature at low temperature oil supply to about 40 ℃
Set to (measured temperature), the cycle of supplying 196 ° C. silicon oil and room temperature silicon oil alternately every one hour is set as one cycle (2 hours), and the number of cycles during the test is set to 100 cycles. Sample No. when supplying high temperature oil and when supplying low temperature oil. 1-NO. The leakage situation of No. 8 was measured.

Table 1 below shows sample NO. 1 to
NO. 8 is the result of performance test of No. 8.

[0025]

[Table 1]

As a result of the test, the sample NO. 1-NO. With respect to No. 4, even if the operation of alternately circulating and supplying high-temperature silicone oil and normal-temperature silicone oil is repeated 100 cycles, no leakage occurs and good test results are obtained.

Therefore, when connecting the quartz tube 3 having a tube diameter of 19 mm or a tube diameter of 8 mm, the tightening nut 4 should be tightened by hand at the time of initial installation, and then the screw should be tightened by 1/2 turn with a spanner or the like. And the leakage of the transport fluid can be reliably prevented. Moreover, since the retaining ring 5 is fitted and fixed in the peripheral groove 3b formed in the quartz tube 3, the sample No. 1 to N
O. Even if high pressure and high temperature are applied to the quartz tube 3, the quartz tube 3 does not come off, and a high tube holding force exceeding the breakage limit of the quartz tube 3 itself can be obtained.

As shown by the above test results, the joint body 2
After inserting the end portion 3a of the quartz tube 3 into the one end side connecting portion 2a of the quartz tube 3, the tightening ring 6 is deformed by reducing the diameter on the outer peripheral surface of the quartz tube 3 and fixed by crimping, so that leakage of the transport fluid or the like is surely performed. Not only is it prevented, but also the quartz tube 3 and the quartz tube 3 or the quartz tube 3 and the other synthetic resin tube 7 can be easily connected, and the workability can be improved.

Moreover, since the retaining ring 5 is fitted and fixed in the peripheral groove 3b engraved on the outer peripheral surface of the quartz tube 3 for retaining and fixing, a high retaining force exceeding the breaking limit of the quartz tube 3 itself is exerted. Since it is a material that is highly safe and reliable, and has a high joint function and is not easily adversely affected by changes in fluid pressure and temperature, the maximum operating temperature (200 ° C) and maximum operating pressure (2 kg at all times) / Cm ² ) is greatly improved and the range of application as a pipe joint can be expanded.

The quartz pipe fitting 1 of the second embodiment shown in FIG.
Instead of the tightening ring 6 used in the above-mentioned first embodiment, a groove 2c is formed on the inner peripheral surface of the insertion recess 10 formed in the one end side connecting portion 2a of the joint body 2, and the groove 2c is made of fluorine. After inserting the O-ring 29 formed of a system resin, the insertion recess 10 formed in the one end side connection portion 2a of the joint body 2
Since the end portion 3a of the quartz tube 3 is inserted in and the O-ring 29 is pressure-tightly sealed on the outer peripheral surface of the quartz tube 3 to seal,
The same effect as that of the above-described first embodiment can be obtained.

The present invention is not limited to the configuration of the above-mentioned embodiment, and the joint structure of the quartz pipe joint 1 constituting the present invention connects the quartz pipe 3 to the quartz pipe 3. It can also be applied to a pipe joint (not shown) dedicated to a quartz pipe used for.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a quartz pipe joint of a first embodiment.

FIG. 2 is a vertical sectional side view of a quartz pipe joint.

FIG. 3 is a block diagram of a heat cycle test apparatus showing a test method for a quartz pipe joint.

FIG. 4 is a sample piping diagram showing a piping state of a quartz pipe joint.

FIG. 5 is a time chart diagram showing thermal cycle temperature conditions during a test.

FIG. 6 is a vertical sectional side view showing a quartz pipe joint of a second embodiment.

FIG. 7 is a vertical sectional side view showing a conventional pipe joint.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Quartz pipe joint 2 ... Joint main body 2a, 2b ... Connection part 3 ... Quartz pipe 3b ... Circumferential groove 4 ... Tightening nut 5 ... Detachment ring 6 ... Tightening ring 6b, 10a ... Tapered surface 7 ... Synthetic resin tube

Claims (1)

[Claims] 1. An end portion of a quartz tube is inserted into a connection portion on one end side of a joint body, and a tightening nut inserted on an outer peripheral surface of the quartz tube and a connection portion on one end side of the joint body are screwed together, While matching the tapered surfaces formed on the end portion of the tightening nut and the one end side connection portion of the joint body, the tightening ring is contracted and deformed in the direction of being crimped and fixed on the outer peripheral surface of the quartz tube. A retaining ring is fitted and fixed in a peripheral groove formed on the outer peripheral surface of the quartz tube, and the retaining ring is inserted between the opposing surfaces of the tightening nut and the clamping ring inserted on the quartz tube. A quartz pipe fitting to hold.