|
DE1271479B
|
|
Shut-off device for highly viscous media
|
|
DE1003669B
|
|
Process for the production of drilling fluids
|
|
DE1083755B
|
|
Connection of well filter and well attachment pipes made of plastic
|
|
GB776306A
|
|
Improvements in or relating to valves for pipings of all kinds, preferably preventertype valves for petroleum bore-holes
|
|
DE1062508B
|
|
Shut-off device with a cylindrical elastic locking piece and holding device for the locking piece
|
|
DE1062512B
|
|
Shut-off device, in particular shut-off valve
|
|
DE1063431B
|
|
Shut-off device with piston valve
|
|
DE1053264B
|
|
Stopcock with a cylindrical plug, which consists of a slotted hollow body
|
|
DE868876C
|
|
Pipe well filter made of malleable, especially ceramic building materials
|
|
DE872479C
|
|
Pipe well filters made of non-metallic building materials, in particular stoneware
|
|
DE907394C
|
|
Tube well filter
|
|
DE733951C
|
|
Closure piece for observation well
|
|
DE729653C
|
|
Tube well filters, in particular made of ceramic material
|
|
DE724242C
|
|
Well filter attachment pipe made of wood or similar materials
|
|
DE724492C
|
|
Pipe well filter made of wood and similar materials
|
