e-SYNC - Applications - Clay Impression Core Orientation

Introduction

Specifications

Instrument Window Info

Wireless Antenna Port

Adding Survey Information

Operating Instructions

Single Shot Automatic

Single Shot Timed

Multi Shot Timed

Realtime

Working with Stored Data

View Previous Data

Building Output File

Administrative Options

Applications

Overshot

Core Orientation

Open Hole

The standard clay impression method has been adapted to be used with the e-SYNC tool-facing and inclination determining instrument.

With the accurately aligned elements in the Clay Impression Dropper Assembly, the e-SYNC can provide clay impressions with tool facing accuracies of ± 1 degree and simultaneous inclination to ± 1/2 degree.

This diagram shows the e-SYNC with the application hardware required for the clay impression core orientation application.

The spearhead attaches to the top of the Quik-Connect coupling, which attaches to the top of the e-SYNC.

A clay impression dropper specific to you core diameter attaches to the bottom of the e-SYNC by means of the Quik-Connect coupling.

The e-SYNC has an “index line” marked on its body, which references the 0º position when using the tool facing capabilities of the instrument.

This “index line” is calibrated to line up to the corresponding “index line” on the clay dropper by means of the Pajari Quik-Connect coupling.

Clay Selection

The clay is available in grades #2 and #4. The #2 clay is softer and should be used when the rock is soft (shale, for example), or when the hole is in permafrost. The #4 clay is harder and is for use in normal rock and in warmer holes. It remains fairly firm even when warmed. It may take a mixture of both clays to provide an appropriate consistency for the particular core being oriented.

Clay Shoe Setup

The Clay Impression Dropper has a Clay Shoe which is threaded onto the down-hole end to hold the clay in place . New clay should never be added to a shoe that has old clay in it. The old clay should be removed from the shoe and cleaned of rock particles, and only then mixed with new clay and packed back into the shoe. After the appropriate clay selection has been made, work the clay into the clay shoe with your thumb and fingers. Enough clay will be needed to allow the clay to protrude through the bit. The clay should be packed tightly into the shoe, around the hooks and into the side wall grooves of the shoe casing. Make sure that any seams in the clay caused by the addition of clay or the packing process have been sufficiently worked together so that separation does not occur. If the clay is particularly stiff and hard to work into the shoe, warming it will make it softer and more pliable.

The clay should extend through the bit and be flush with the front face of the crown (see Fig. 1). The diameter of the clay should be such that it does not pack against the inside diameter of the crown. Using too much clay that extends past the front face of the crown or packs against the inside diameter will cause the clay to pack into the water ways of the bit when the impression is made. If the clay packs into the water ways, the clay may be pulled from the shoe and lost when the orienting barrel is retrieved. The Clay Shoe should always be checked against the core lifter casing being used in the drilling operation to ensure that is the same in size and shape and correctly fits the bit as depicted in Fig. 2.

Setting the e-SYNC

Setting Up The Clay Impression Dropper

Thread a packed Clay Shoe onto the Clay Impression Dropper and tighten with core barrel wrenches. Take care not to damage the shape of the clay when installing and tightening the Clay Shoe.
Connect the e-SYNC to the Clay Impression Dropper means of the Pajari Quik-Connect couplings.

Impression Procedure

Once the core run is complete, retrieve the core and core barrel using standard procedures. Pull the rod string up 15cm (6”) off the bottom of the hole.
Fill the drill string and hole with water. Most drilling fluids and mud will not affect the clay, in most cases they actually improve the impression.
Set time/surveying mode on the e-SYNC.
Insert the Core Orientation Assembly into the drill rod string and release it to free fall in the hole. Use caution when inserting the barrel to ensure the clay pack is not damaged.
Apply water pressure to assist the assembly to the bottom of the hole. The assembly reaching the bottom of the rod string will be indicated by a large increase in water pressure. Once the assembly is securely in place, slowly lower the rods against the core stub using slight water pressure to keep the clay pack against the bit. Once the rods are at the bottom of the hole, increase the water pressure to ensure the clay pack is solidly against the bit. The rods should not be rotated while lowering the rod string into position or once the impression is made.
Send the overshot down the hole on the wire-line cable.
Retrieve the clay Impression Assembly from the drill string and check the clay pack for a good impression.
Extend the Index Line onto the Clay Shoe. This extension should be done with a paint pen or other marker. The Clay Shoe with impression of the core can now be removed.
Download survey readings from e-SYNC.