Title (en)

Drill hammer assembly

Title (de)

Bohrhammeranordnung

Title (fr)

Ensemble de marteaux de forage

Publication

EP 1138870 A1 20011004 (EN)

Application

EP 01302804 A 20010327

Priority

ZA 200000509 A 20000327

Abstract (en)

The invention concerns a down the hole drill hammer assembly providing a full piston area exposure to driving fluid pressure by the omission of the usual finger valve from the upper piston area and providing the piston with blind bores at each end and passages through the piston wall enabling predetermined communication between the blind bores for exhausting pressure fluid through the drill bit assembly. Fluid transfer passages are also provided in the inner wall of an outer wear sleeve of the drill hammer assembly. <IMAGE>

IPC 1-7

E21B 4/14

IPC 8 full level

E21B 4/14 (2006.01)

CPC (source: EP)

E21B 4/14 (2013.01)

Citation (search report)

• [X] US 3804181 A 19740416 - CURINGTON A, et al
• [A] WO 9957411 A1 19991111 - PERMON S R O [CZ], et al
• [A] US 3692122 A 19720919 - CURINGTON ALFRED R
• [A] US 4094366 A 19780613 - GIEN ABRAHAM, et al
• [A] US 5080179 A 19920114 - GIEN ABRAHAM [ZA], et al
• [A] EP 0851091 A2 19980701 - TERRA AG TIEFBAUTECHNIK [CH]

Designated contracting state (EPC)

AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR

DOCDB simple family (publication)

EP 1138870 A1 20011004; CA 2342140 A1 20010927

DOCDB simple family (application)

EP 01302804 A 20010327; CA 2342140 A 20010327