阅读说明：本技术 一种聚四氟乙烯内衬钢管的高压定型工艺 (High-pressure shaping process of polytetrafluoroethylene lining steel pipe ) 是由 薛家伟 彭传全 刘宏 于 2021-02-04 设计创作，主要内容包括：本发明公开了一种聚四氟乙烯内衬钢管的高压定型工艺,包括以下步骤：模芯和钢管同轴设置,在所述钢管的两端加装加料环,在模芯外表面套上橡胶皮套,在钢管与橡胶皮套之间填装聚四氟乙烯粉料后,取出所述模芯；在钢管两端加装盖板,采用螺栓将所述盖板固定在所述钢管两端的法兰上,位于一端的盖板上设置有进水口；采用电动试压泵接通所述进水口,向内充水,并加压至10MPa,使聚四氟乙烯粉料在钢管内受到较高水压定型。本发明采用高压使聚四氟乙烯粉料定型,定型工艺简单环保,且定型效果良好。(The invention discloses a high-pressure shaping process of a polytetrafluoroethylene lining steel pipe, which comprises the following steps: the method comprises the following steps that a mold core and a steel pipe are coaxially arranged, feeding rings are additionally arranged at two ends of the steel pipe, a rubber leather sleeve is sleeved on the outer surface of the mold core, and the mold core is taken out after polytetrafluoroethylene powder is filled between the steel pipe and the rubber leather sleeve; cover plates are additionally arranged at two ends of the steel pipe, the cover plates are fixed on flanges at two ends of the steel pipe by bolts, and a water inlet is formed in the cover plate at one end; and (3) connecting the water inlet by using an electric pressure test pump, filling water inwards, and pressurizing to 10MPa to enable the polytetrafluoroethylene powder to be subjected to higher water pressure in the steel pipe for shaping. The invention adopts high pressure to shape the polytetrafluoroethylene powder, and the shaping process is simple and environment-friendly and has good shaping effect.)

1. A high-pressure shaping process of a polytetrafluoroethylene lining steel pipe is characterized by comprising the following steps:

the mold core and the steel pipe are coaxially arranged, the mold core is not in contact with the steel pipe, and two ends of the mold core along the length direction slightly protrude out of two ends of the steel pipe;

adding material rings at two ends of the steel pipe, and sleeving a rubber leather sleeve on the outer surface of the mold core;

filling polytetrafluoroethylene powder between the rubber leather sheath and the steel pipe, and tamping the polytetrafluoroethylene powder in the filling process;

taking out the feeding ring, additionally installing a first annular gasket and a second annular gasket at two ends of the steel pipe, wherein the inner sides of the first annular gasket and the second annular gasket are sleeved on the rubber leather sheath, the outer sides of the first annular gasket and the second annular gasket are at least flush with the outer wall of the flange of the steel pipe, the first annular gasket is positioned below the rubber leather sheath, and the second annular gasket is positioned above the rubber leather sheath;

taking out the mold core;

cover plates are additionally arranged at two ends of the steel pipe, the cover plates are fixed on the flanges by bolts, and a water inlet is formed in the cover plate at one end;

and (3) connecting the water inlet by using an electric pressure test pump, filling water into the water inlet, and pressurizing to 10MPa to ensure that the polytetrafluoroethylene powder is shaped in the steel pipe at high pressure.

2. The process of claim 1 wherein the die core is sized to approximate the dimensions of the steel pipe flow-through section.

3. The process for high pressure sizing a polytetrafluoroethylene lined steel pipe as set forth in claim 1 wherein the inside diameter of said first annular shim and said second annular shim is equal to the outside diameter of said rubber boot.

4. The high-pressure sizing process for the polytetrafluoroethylene-lined steel pipe according to claim 1, wherein a plurality of first through holes are formed in the first annular gasket at intervals, a plurality of second through holes are formed in the second annular gasket at intervals, and the bolts penetrate through the first through holes and the second through holes and are fixed on the flange.

Technical Field

The invention relates to the technical field of pipe processing. More specifically, the invention relates to a high-pressure shaping process of a polytetrafluoroethylene lining steel pipe.

Background

The steel-lined polytetrafluoroethylene PTFE steel pipe and the steel-lined polytetrafluoroethylene PTFE steel pipe fittings are well known as the plastic king, have excellent temperature resistance and corrosion resistance, and are ideal conveying equipment for organic solvents such as nitric acid, sulfuric acid, hydrofluoric acid, phosgene, chlorine, aqua regia, mixed acid, bromide and the like and other strongly corrosive media.

The existing preparation process of the steel-lined tetrafluoride pipe easily causes the thickness of a polytetrafluoroethylene lining to be inconsistent, the quality of the steel-lined tetrafluoride pipe is influenced, and when negative pressure occurs in a steel pipe, the lining of the tetrafluoride pipe is easily separated from the inner wall of the steel pipe.

Disclosure of Invention

An object of the present invention is to solve at least the above problems and to provide at least the advantages described later.

The invention also aims to provide a high-pressure shaping process of the polytetrafluoroethylene lining steel pipe, which adopts an electric pressure test pump to fill water and pressurize to shape polytetrafluoroethylene powder, and has the advantages of simple and environment-friendly shaping process and good shaping effect.

To achieve these objects and other advantages in accordance with the purpose of the invention, there is provided a high pressure sizing process of a teflon-lined steel pipe, comprising the steps of:

the mold core and the steel pipe are coaxially arranged, the mold core is not in contact with the steel pipe, and two ends of the mold core along the length direction slightly protrude out of two ends of the steel pipe;

adding material rings at two ends of the steel pipe, sleeving a rubber leather sleeve on the outer surface of the mold core, wherein the vertical section of the rubber leather sleeve is I-shaped;

filling polytetrafluoroethylene powder between the rubber leather sheath and the steel pipe, and tamping the polytetrafluoroethylene powder in the filling process;

taking out the feeding ring, additionally installing a first annular gasket and a second annular gasket at two ends of the steel pipe, wherein the inner sides of the first annular gasket and the second annular gasket are sleeved on the rubber leather sheath, the outer sides of the first annular gasket and the second annular gasket are at least flush with the outer wall of the flange of the steel pipe, the first annular gasket is positioned below the rubber leather sheath, and the second annular gasket is positioned above the rubber leather sheath;

taking out the mold core;

cover plates are additionally arranged at two ends of the steel pipe, the cover plates are fixed on the flanges by bolts, and a water inlet is formed in the cover plate at one end;

and (3) connecting the water inlet by using an electric pressure test pump, filling water into the water inlet, and pressurizing to 10MPa to ensure that the polytetrafluoroethylene powder is shaped in the steel pipe at high pressure.

Preferably, the size of the mold core is similar to the design size of the flow-through part of the steel pipe.

Preferably, the inner diameter of the first annular gasket and the inner diameter of the second annular gasket are equal to the outer diameter of the rubber leather sheath.

Preferably, a plurality of first through holes are formed in the first annular gasket at intervals, a plurality of second through holes are formed in the second annular gasket at intervals, and the bolts penetrate through the first through holes and the second through holes to be fixed on the flange.

The invention at least comprises the following beneficial effects: an electric pressure test pump is adopted to connect the water inlet, water is filled inwards, and the pressure is increased to 10MPa, so that the polytetrafluoroethylene powder is shaped in the steel pipe at high pressure, the shaping process is simple and environment-friendly, and the shaping effect is good.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.

Detailed Description

The present invention is further described in detail below with reference to examples so that those skilled in the art can practice the invention with reference to the description.

It is to be noted that the experimental methods described in the following embodiments are all conventional methods unless otherwise specified, and the reagents and materials are commercially available unless otherwise specified.

The invention provides a high-pressure shaping process of a polytetrafluoroethylene lining steel pipe, which comprises the following steps:

the mold core and the steel pipe are coaxially arranged, so that the circulating part formed at the mold core is positioned in the middle of the steel pipe.

The mold core is not in contact with the steel pipe, and two ends of the mold core along the length direction slightly protrude out of two ends of the steel pipe; the size of the mold core is similar to the design size of the steel pipe circulation part.

The feeding rings are additionally arranged at the two ends of the steel pipe, the rubber leather sleeve is pasted on the outer surface of the mold core, and the vertical section of the rubber leather sleeve is I-shaped;

filling polytetrafluoroethylene powder between the mold core and the steel pipe, and tamping the polytetrafluoroethylene powder in the filling process to form an annular cylinder attached to the rubber leather sheath and the steel pipe;

taking out the feeding ring, additionally installing a first annular gasket and a second annular gasket at two ends of the steel pipe, wherein the inner sides of the first annular gasket and the second annular gasket are sleeved on the rubber leather sheath, the outer sides of the first annular gasket and the second annular gasket are at least flush with the outer wall of the flange of the steel pipe, the first annular gasket is positioned below the rubber leather sheath, and the second annular gasket is positioned above the rubber leather sheath;

taking out the mold core;

cover plates are additionally arranged at two ends of the steel pipe, the cover plates are fixed on the flanges by bolts, and a water inlet is formed in the cover plate at one end;

connecting the water inlet by using an electric pressure test pump, filling water into the water inlet, and pressurizing to 10MPa to enable the polytetrafluoroethylene powder to be shaped in the steel pipe at high pressure;

sintering and forming to obtain the polytetrafluoroethylene lining steel pipe.

In order to enable the first annular gasket and the second annular gasket to have supporting points in the installation process, the mold core is taken out after the first annular gasket and the second annular gasket are installed.

If the formed polytetrafluoroethylene lining is a straight pipe, two ends of the annular column body are flush with two ends of the steel pipe; if the steel lining steel pipe is an elbow, a two-way pipe, a three-way pipe and the like, the lining comprises a main pipe and a bulge pipe, the main pipe is matched with the steel pipe, and the bulge pipe is positioned at two ends of the steel pipe.

While embodiments of the invention have been described above, it is not limited to the applications set forth in the description and the embodiments, which are fully applicable to various fields of endeavor for which the invention may be embodied with additional modifications as would be readily apparent to those skilled in the art, and the invention is therefore not limited to the details given herein and to the embodiments shown and described without departing from the generic concept as defined by the claims and their equivalents.