Method for welding molded bodies

Patent metadata

Field	Value
Publication number	US-11090877-B2
Application number	US-201716302316-A
Country	US
Kind code	B2
Filing date	May 5, 2017
Priority date	May 17, 2016
Publication date	Aug 17, 2021
Grant date	Aug 17, 2021

Abstract

A process for welding a first molding to a second molding. The process uses an implement including first and second external surfaces. Each external surface further includes a duct. An end of the first molding is heated by a hot gas while the end is at a distance from the duct-entry plane in the range from 3 mm outside the duct to 10 mm inside the duct. A junction area of the second molding is heated by a hot gas while the junction area is at a distance from the duct-entry plane in a range from 3 mm outside the duct to 10 mm inside the duct. The heated end and the heated junction area are then brought into contact with one another and cooled, forming a weld between the first molding and the second molding. Also disclosed is a welded molding obtainable by the process of the invention.

First claim

The invention claimed is:

1. A process for the welding of a first molding ( 11 a ) to a second molding ( 1 b ),
where the first molding ( 1 a ) comprises a first lateral area ( 3 a ), a second lateral area ( 4 a ) and an end ( 2 a ), which comprises a first thermoplastic polymer, and
where the second molding ( 1 b ) comprises a junction area ( 2 b ) which comprises a second thermoplastic polymer,
comprising the steps of
a) provision of the first molding ( 1 a ),
b) provision of the second molding ( 1 b ),
c) provision of an implement ( 5 ) which has a first external area ( 6 a ) and a second external area ( 6 b ),
where the first external area ( 6 a ) comprises a duct ( 7 a ), and where the duct ( 7 a ) has a floor ( 10 a ), a first duct wall ( 8 a ) with a first highest point ( 12 a ) and a second duct wall ( 9 a ) with a second highest point ( 13 a ), where the floor ( 10 a ) comprises a means ( 11 a ) for the introduction of gas into the duct ( 7 a ), where a duct-entry plane ( 14 a ) runs through the first highest point ( 12 a ) parallel to the first external area ( 6 a ) and where the location of an exterior duct region ( 17 a ) is between a projection line ( 15 a ) from the first highest point ( 12 a ) along a direction running perpendicularly to the duct-entry plane ( 14 a ) and a projection line ( 16 a ) from the second highest point ( 13 a ) along a direction running perpendicularly to the duct-entry plane ( 14 a ),
where the second external area ( 6 b ) comprises a duct ( 7 b ), and where the duct ( 7 b ) has a floor ( 10 b ), a first duct wall ( 8 b ) with a first highest point ( 12 b ) and a second duct wall ( 9 b ) with a second highest point ( 13 b ), where the floor ( 10 b ) comprises a means ( 11 b ) for the introduction of gas into the duct ( 7 b ), where a duct-entry plane ( 14 b ) runs through the first highest point ( 12 b ) parallel to the second external area ( 6 b ) and where the location of the exterior duct region ( 17 b ) is between a projection line ( 15 b ) from the first highest point ( 12 b ) along a direction running perpendicularly to the duct-entry plane ( 14 b ) and a projection line ( 16 b ) from the second highest point ( 13 b ) along a direction running perpendicularly to the duct-entry plane ( 14 b ),

d) positioning of the first molding ( 1 a ), where
a distance (Xa) of the end ( 2 a ) from the duct-entry plane ( 14 a ) in a direction running perpendicularly to the duct-entry plane ( 14 a ) is in the range from 3 mm outside the duct ( 7 a ) to 10 mm inside the duct ( 7 a ), where
if the distance (Xa) is in the range from >0 mm to 3 mm outside the duct ( 7 a ), the location of the end ( 2 a ) is at least to some extent in the exterior duct region ( 17 a ),
and if the distance (Xa) is in the range from 0 mm to 10 mm inside the duct ( 7 a ), a minimal distance (Y 1 a ) of the first lateral area ( 3 a ) from the first duct wall ( 8 a ) is in the range from 0.2 to 5 mm, and a minimal distance (Y 2 a ) of the second lateral area ( 4 a ) from the second duct wall ( 9 a ) is in the range from 0.2 to 5 mm,

e) positioning of the second molding ( 1 b ), where
a distance (Xb) of the junction area ( 2 b ) from the duct-entry plane ( 14 b ) in a direction running perpendicularly to the duct-entry plane ( 14 b ) is in the range from 3 mm outside the duct ( 7 b ) to 10 mm inside the duct ( 7 b ), where
if the distance (Xb) is in the range from >0 mm to 3 mm outside the duct ( 7 b ), the junction area ( 2 b ) is at least to some extent in the exterior duct region ( 17 b ),
and if the distance (Xb) is in the range from 0 mm to 10 mm inside the duct ( 7 b ), the second molding ( 1 b ) additionally has a first lateral area ( 3 b ) and a second lateral area ( 4 b ) and a minimal distance (Y 1 b ) of the first lateral area ( 3 b ) from the first duct wall ( 8 b ) is in the range from 0.2 to 5 mm, and where a minimal distance (Y 2 b ) of the second lateral area ( 4 b ) from the second duct wall ( 9 b ) is in the range from 0.2 to 5 mm,

f) introduction of a hot gas via the means ( 11 a ) for the introduction of gas into the duct ( 7 a ), where the temperature of the end ( 2 a ) of the first molding ( 1 a ) increases to a temperature T 1a and where the first thermoplastic polymer comprised in the end ( 2 a ) melts,
g) introduction of a hot gas via the means ( 11 b ) for the introduction of gas into the duct ( 7 b ), where the temperature of the junction area ( 2 b ) of the second molding ( 1 b ) increases to a temperature T 1b and where the second thermoplastic polymer comprised in the junction area ( 2 b ) melts,
h) removal of the first molding ( 1 a ) from the position achieved in step d),
i) removal of the second molding ( 1 b ) from the position achieved in step e),
j) bringing of the heated end ( 2 a ) of the first molding ( 1 a ) into contact with the heated junction area ( 2 b ) of the second molding ( 1 b ) and cooling of the heated end ( 2 a ) of the first molding ( 1 a ) to a temperature T 2a and of the heated junction area ( 2 b ) of the second molding ( 1 b ) to a temperature T 2b while the heated end ( 2 a ) and the heated junction area ( 2 b ) are in contact with one another to form a weld between the first molding ( 1 a ) and the second molding ( 1 b ).

2. The process according to claim 1 , wherein the temperature (T 1a ) to which the temperature of the end ( 2 a ) of the first molding ( 11 a ) increases in step f) is above the glass transition temperature (TO of the first thermoplastic polymer comprised in the end ( 2 a ) if the first thermoplastic polymer is an amorphous thermoplastic polymer, and is above a the melting point (T M1 ) of the first thermoplastic polymer comprised in the end ( 2 a ) if the first thermoplastic polymer is a semicrystalline thermoplastic polymer, and/or the temperature (T 1b ) to which the temperature of the junction area ( 2 b ) increases in step g) is above the glass transition temperature (T G2 ) of the second thermoplastic polymer comprised in the junction area ( 2 b ) if the second thermoplastic polymer is an amorphous thermoplastic polymer, and is above the melting point (T M2 ) of the second thermoplastic polymer comprised in the junction area ( 2 b ) if the second thermoplastic polymer is a semicrystalline thermoplastic polymer.

3. The process according to claim 1 , wherein the first thermoplastic polymer comprised in the end ( 2 a ) is selected from the group consisting of polyamides, polyoxymethylenes, polysulfone, polyphenyl sulfone and polybutylene terephthalates, and/or the second thermoplastic polymer comprised in the junction area ( 2 b ) is selected from the group consisting of polyamides, polyoxymethylenes, polysulfone, polyphenyl sulfone and polybutylene terephthalates.

4. The process according to claim 1 , wherein the first thermoplastic polymer comprised in the end ( 2 a ) and the second thermoplastic polymer comprised in the junction area ( 2 b ) are identical.

5. The process according to claim 1 , wherein the temperature (T 1a ) to which the temperature of the end ( 2 a ) of the first molding ( 11 a ) increases in step f) is in the range from 0 to 300° C. above the glass transition temperature (TO of the first thermoplastic polymer comprised in the end ( 2 a ) if the first thermoplastic polymer is an amorphous thermoplastic polymer, and is in the range from 0 to 300° C. above the melting point (T M1 ) of the first thermoplastic polymer comprised in the end ( 2 a ) if the first thermoplastic polymer is a semicrystalline thermoplastic polymer, and/or the temperature (T 1b ) t

Assignees

• Basf Se

Inventors

• Mochev Stefan
• Endemann Ulrich

Classifications

• B29C66/929

  characterized by specific pressure, force, mechanical power or displacement values or ranges · CPC title

• B29C66/9261

  by controlling or regulating the displacement of the joining tools · CPC title

• B29C66/91413

  the parts to be joined having different temperatures · CPC title

• B29C66/00141

  Protective gases · CPC title

• B29C66/91411

  of the parts to be joined, e.g. the joining process taking the temperature of the parts to be joined into account · CPC title