Lubricated fishing bumper sub is one of the jars which produce jarring force by means of the energy caused by heavy weight objects when moving down, its inner chamber is full of hydraulic oil so as to ensure a longer service life. The tool is suitable for deep hole and middle deep hole operation. With some advantages: Can produce strong one way down jarring force, maximum jarring force, continuous down jarring force. Medium jarring force; continuous up jar, low-grade jarring force; can release fishing tool; can act as constant pressure drill tool, simply structure, easy operation, allthesemakeitwidely used jarring tool.
Working Principle
Energy conversion in jarring operation
Downward is made by means of conversion. Raising drill stem shall make bumper jar to be pulled down at a certain height to produce potential energy. Go on raising drill stem, the drill stem has a strain energy due to spring strain. When drill stem is lowered suddenly, the energy stored in drill stem the force the drill stem to move downward in acceleration. When bumper sub reaches a closed position, the above energies at this instant change into a large downward jarring force.
Main factors having influenced on jarring force.
Many factors influence on jarring force, but key factors as follows: 1,The bigger hanging weight on top drill stem of bumper jar makes a bigger jarring force. 2,The longer the spring extension of drill stem is when raising drill stem, the bigger the jarring force is. 3,The longer the stroke of the bumper jar is, the bigger the jarring force of jar is.

Tianhe Oil Group Huifeng Petroleum Equipment Co., Ltd is a modernized medium-scale enterprise specialized in production of oil and gas tools.
As an API-Certified established manufacturer and supplier of a comprehensive range of downhole equipment with related accessories, we are committed to providing the highest Quality products for the Petroleum and natural gas industry since 1973.
Tianhe Oil Group strongly believes and promotes Total Quality Management, implement the ISO quality management system and HSE management system and API Standard, which has been deeply implanted into every person's thought and carried out into every aspect of work.
Our manufacturing facilities are well equipped with four automated induction heat treatment lines and dozens of other types of heat treatment ovens and well furnaces to ensure full coverage of heat treatment requirements by different products to achieve the required mechanical properties.
In order to ensure the quality consistency and interchangeability of high precision components, Tianhe has introduced WFL 5-axis Linkage Turning & Milling Machining Center from Austria, Mazak's turn milling machining center from Japan and the Haas vertical machining center from USA. These processes are facilitated with precise quality inspection equipment such as the Brunker OES Metal Analyzers from Germany, Ultrasonic and Magnetic Powder Flaw Detector and high precision Hexagon Three Coordinate Measuring Machine and Farco Portable Three Coordinate Measuring Machine.
So far, Tianhe Oil Group has established strong business relationships with over 200 international oil & gas companies in supporting the top 50 oil producing countries.
We take pride in delivering superior performances and reliability. Our objective is to exceed your expectations, improve your economics and be an integral part of your strategies.









