Tri-axial shock absorber sub
A downhole shock absorbing sub which includes a tubular main stem extending through a sub housing and a lateral shock absorbing assembly positioned within the sub housing. The lateral shock absorbing assembly includes an activator ring positioned around the main stem, the activator ring including a plurality of wedge inserts positioned around a perimeter of the activator ring. A reaction collar is positioned on each side of the activator ring with the reaction collars including ramp surfaces engaged by the wedge inserts. A spring system is positioned to resist movement of the reaction collars away from the activator ring, whereby lateral movement of the main stem causes the wedge inserts to move the reaction collars against the spring system.
1. A downhole shock absorbing sub comprising:
(a) a tubular main stem extending through a sub housing;
(b) a torsional shock absorbing assembly positioned within the sub housing and comprising:
(i) a first helix sleeve configured to rotate with the main stem, the first helix sleeve having a first helical cam surface formed on an end surface of the sleeve;
(ii) a second helix sleeve configured to translate relative to the main stem, the second helix sleeve having a second helical cam surface formed on an end surface of the sleeve and engaging the first helical cam surface;
(iii) a spring system positioned to resist movement of the first and second helix sleeves away from one another; and
(c) an axial shock absorbing assembly positioned within the sub housing and comprising:
(i) a load collar fixed axially on the main stem, wherein the load collar has a series of splines engaging corresponding spline grooves of the main stem;
(ii) a spring system configured to resist axial movement of the load collar relative to the sub housing, wherein the spring system is a bank of spring washers;
(c) whereby rotational movement of the main stem causes the first and second helical cam surfaces to move (i) the first and second helix sleeves apart, and (ii) at least one of the first or second helix sleeves into engagement with the spring system of the torsional shock assembly.
2. The shock absorbing sub of claim 1 , wherein the second helix sleeve engages the spring system of the torsional shock assembly.
3. The shock absorbing sub of claim 2 , further including a series of axially oriented anti-rotation splines preventing rotation of the second helix sleeve relative to the sub housing.
4. The shock absorbing sub of claim 1 , wherein the spring system of the torsional shock assembly is a bank of spring washers.
5. The shock absorbing sub of claim 1 , wherein the axial shock absorbing assembly further comprises:
(iii) first and second seal collars positioned to bracket the load collar and spring system between the seal collars and control the flow of a fluid in which the load collar and spring system are immersed.