Specifications
API 7-1 DHJ Type Mechanical Hydraulic Shock SubAPI Connection
Size 4 3/4" ~ 8 "
Used for reducing vibrations
API 7-1 DHJ Type Mechanical Hydraulic Shock Sub
The mechanical and hydraulic shock sub type DHJ is a two-function shock sub that absorbs the pulsate and shock from drill tools by compressing spring and SI oil to store the energy. It is used for reducing vibrations caused by hard formation drilling and keeping the drill bit firmly on the bottom, so that it helps to reduce drill string connection fatigue and prolong drill string life.
Specification Series and Performance Parameters
Type | O.D. mm(in) | I.D. mm(in) | Overall Stroke mm(in) | Max. Working Load mm(in) | Ambient Temperature °C | Connection API | Overall Length “Extended” mm(in) |
DHJ121 | 121 (4 3/4) | 38 (1 1/2) | 100(3.93) | 40(1.57) | - 40~150 | 31/2REG | 3400 (133.85) |
DHJ159 | 159 (6 1/4) | 50.8 (2) | 120(4.72) | 60(2.36) | - 40~150 | NC46 | 4210 (165.75) |
DHJ 178 | 178 (7) | 57 (2 1/4) | 120(4.72) | 60(2.36) | - 40~150 | NC50 | 4210 (165.75) |
DHJ203 | 203 (8) | 71.4 (2 4/5) | 140(5.51) | 70(2.75) | - 40~150 | 65/8REG | 4700 (185) |