Seal assembly for valves

Claim 2

A ball valve assembly comprising: an all-plastic valve body including a main body section and oppositely disposed end sections, one of said end sections being separately connectable to the main body section, said end sections having flow passages therein and said main body section having a central valving chamber, said flow passages and said valving chamber defining in assembly a fluid flow path through said body, said one of said end sections and said main body section having fusible annular projecting surfaces thereon; a ball member in the valving chamber having a through port, said ball member being rotatable between an open position wherein the port communicates with the flow passages for permitting fluid flow therebetween and a closed position wherein the ball disconnects the flow passages for preventing fluid flow therebetween; means for rotating said ball member; a first seat element retained in said valving chamber by a first seat retainer adjacent the other of said end sections, the ball member being continuously engaged by said first seat element; abutment face means on each of said main body section and said one of said end sections; a second seat element retained by a second seat retainer which said second seat retainer has spaced surfaces respectively engageable by the abutment face means, said spaced surfaces having an axial length between them less than the space between the abutment face means in initial assembly, said second seat element being engageable with the ball member, said projecting surfaces being fused and compressed to fixedly grip the second seat retainer to establish a preload between the seat elements and the ball member and desired assembled dimensional relationships.

Claim 3

The ball valve assembly of claim 1 wherein said seat retainers are provided with venting means for interconnecting the space between said seat retainers and said body with said valving chamber.

Claim 4

The ball valve assembly of claim 1 wherein said end sections include surfaces contacting said ball member upon overload of the said ball member.

Claim 5

A ball valve assembly comprising: an all plastic valve body including a main body section and oppositely disposed end sections, one of said end sections being separately connectable to the main body section, said end sections having flow passages therein and said main body section having a central valving chamber, said flow passages and said valving chamber defining in assembly a fluid flow path through said body, said one of said end sections and said main body section having fusible annular projecting surfaces thereon; a ball member in the valving chamber having a through port, said ball member being rotatable between positions where it blocks and provides fluid communication between said flow passages, means for rotating said ball member; a first seat element retained in the valving chamber by a first seat retainer adjacent the other of said end sections, said ball member being continuously engaged by said first seat element; abutment face means on each of the main body section and said one of said end sections; a second seat element retained by a second seat retainer having spaced surfaces respectively engageable by the abutment face means, said spaced surfaces having an axial length between them less than the space between the abutment face means in initial assembly, said second seat element being engageable with the ball member; said main body section, said second seat retainer and said one of said end sections having cooperating surfaces radially orienting said one of said end sections with said main body section; and said projecting surfaces being fused and compressed to fixedly grip the second seat retainer to establish a preload between said seat elements and said ball member in assembled dimensional relationships.

Claim 6

A ball valve assembly comprising: an all plastic valve body including a main body section and oppositely disposed end sections, one of said end sections being separately connectable to the main body section, said end sections having flow passages therein and said main body section having a central valving chamber, said flow passages and said valving chamber defining in assembly a fluid flow path through said body, said one of said end sections and said main body section having fusible annular projecting surfaces thereon; a ball member in the valving chamber having a through port, said ball member being rotatable between positions where it blocks and provides fluid communication between said flow passages, means for rotating said ball member; a first seat element retained in the valving chamber by a first seat retainer adjacent the other of said end sections, said ball member being continuously engaged by said first seat element; abutment face means on each of the main body section and said one of said end sections; a second seat element retained by a second seat retainer having spaced surfaces respectively engageable by the abutment face means, said spaced surfaces having an axial length between them less than the space between the abutment face means in initial assembly, said second seat element being engageable with the ball member; said main body section, said second seat retainer and said one of said end sections having cooperating surfaces radially orienting said one of said end sections with said main body section; and said projecting surfaces being fused and compressed to fixedly grip the second seat retainer to establish a preload between said seat elements and said ball member in assembled dimensional relationships.

Claim 7

A ball valve assembly comprising: an all-plastic valve body including a main body section and oppositely disposed end sections, one of said end sections being separately fusible to the main body section, said end sections having flow passages therein and said main body section having a central valving chamber, said flow passages and said valving chamber defining in assembly a fluid flow path through said body, said one of said end sections and said main body section having fusible annular projecting surfaces thereon; a ball member in the valving chamber having a through port, said ball member being rotatable between positions where it blocks and provides fluid communication between said flow passages, means for rotating said ball member; a first seat element retained in the valving chamber by a first seat retainer; a second seat element retained by a second seat retainer, said ball member being continuously engaged by said seat elements; telescoping cylindrical surfaces on said main body section, said one end section and said second seat retainer capable of sliding engagement to limit relative movement therebetween to axial movement of said sections during fusing of said projecting surfaces whereby said main body section and said one end section are properly radially positioned with respect to each other during the fusing operation to provide a unitary valve assembly with said flow passages correctly radially aligned with said seat elements.

Claim 8

A ball valve assembly comprising: an all-plastic valve body including a main body section and oppositely disposed end sections, one of said end sections being separately fusible to the main body section, said end sections having flow passages therein and said main body section having a central valving chamber, said flow passages and said valving chamber defining in assembly a fluid flow path through said body, said one of said end sections and said main body section having fusible annular projecting surfaces thereon; a ball member in the valving chamber having a through port, said ball member being rotatable between positions where it blocks and provides fluid communication between said flow passages, means for rotating said ball member; a first seat element retained in the valving chamber by a first seat retainer; a second seat element retained by a second seat retainer, said ball member being continuously engaged by said seat elements; telescoping cylindrical surfaces on said main body section, said one end section and said second seat retainer capable of sliding engagement to limit relative movement therebetween to axial movement of said sections during fusing of said projecting surfaces whereby said main body section and said one end section are properly radially positioned with respect to each other during the fusing operation to provide a unitary valve assembly with said flow passages correctly radially aligned with said seat elements.