GB2300659A - Mud bucket - Google Patents

Abstract

A mud bucket comprises a can 1 which is longitudinally split into two sections, the sections being provided with seals 3 along the split and being hinged together at 5. Each section is attached to a respective end of a hydraulic cylinder, such that extending the cylinder causes the mud bucket to close, that is the sections to come together, while retraction of the hydraulic cylinder causes the mud bucket or sections to open allowing the bucket to be placed around a continuous drill string.

Description

"Apparatus for use in relation to Mud Buckets" This apparatus relates to drilling apparatus and more particularly, apparatus for use in relation to Mud Buckets which find utility in the drilling field. A Mud Bucket, as described in this application, is a means of collecting the fluid retained inside a drill string that is being tripped out of the hole, allowing said fluid to be returned to the fluid collection system.

It is necessary when fitting the Mud Bucket to the drill string to make two separate mechanical actions: a) 'Close' the Mud Bucket with enough force to compress and energise the seals; and b) 'Lock' the Mud Bucket in this position while the drill string is being broken.

In the past this has been achieved by 'closing' either by manual, hydraulic or pneumatic means and then 'locking' by a separate independent manual, hydraulic or pneumatic system.

As the closing, locking and opening of the Xud Bucket are physically demanding actions, it is desirable to have a simple mechanical means of applying the necessary forces.

As the mechanical devices which carry out these actions have exposed moving parts, then in the interest of safety, the moving parts should be as small, few and simple as possible.

According to the present invention there is provided a mud bucket comprising a can, the can being spilt longitudinally into two sections, the sections being hinged together to cooperate in a scissor like action and each section being associated with a respective end of one or more hydraulic cylinders operable between an extended position and a retracted position, wherein when the cylinder is in an extended position the sections are caused to be closed together and when the cylinder or cylinders are in a retracted position, the sections are caused to be open.

Preferably, the cylinders are hydraulically activated.

Alternatively pneumatic systems may be used.

An example embodiment will now be described, by way of reference only, which reference to Figure la and lb, wherein; Figure la is a plan view of a mud bucket with the can having been opened to enable the mud bucket to be located around a drill string, and Figure lb shows the mud bucket of Figure la, but in a closed position.

Referring to the Figures, a mud bucket has a can 1 which has a through bore 2 for receiving a drill string (not shown).

Located around the can 1 are elastomer seals 3 at the points where the drill string exits the can 1. The elastomer seals 3 extend along a longitudinal split in the can 1 to prevent the fluid from leaking out of the mud bucket.

The split in the can 1 is longitudinal and causes the can 1 and bucket to be in the form of two sections which are hinged together at 5. By the hinge or pivot 5 the two respective sections of the bucket can act or cooperate together to move in a scissor like action such that the can 1 can be opened for receiving a drill string. In this way the can 1 can be placed around a continuous drill string local to a tool joint where the drill string will be broken and the contained fluid will be expelled.

Each section of the mud bucket is attached via a respective lever 4,6 to a hydraulic cylinder 7. The hydraulic cylinder is operable, via a moveable piston within the cylinder, between an extended position, such as is shown in Figure ib and a closed or retracted position as is shown in Figure la.

When the pistons within the cylinders are caused to move inwards under the pressure of hydraulic fluid, they will act on the hinge levers causing the Mud Bucket to open. The limit of opening will be where the cylinders become fully closed. When the pistons within the cylinders are caused to move outwards by hydraulic fluid, they will act on the hinge levers causing the Mud Bucket to close. The limit of closing will be where the cylinders become fully open.

The lever and cylinder system will allow the closing movement to continue until the various seals are adequately compressed and energised.

The hydraulic cylinders will be fed with hydraulic fluid through a valve system. The valve system will normally have one control lever.

Pushing the control lever one way will allow the Mud Bucket to open. Pushing the control lever the other way will allow the Mud Bucket to close. Releasing the lever will allow it to spring return to the centre position.

With the lever in the centre position, the hydraulic fluid will be locked into the cylinders preventing them from moving in either direction.

There will be a flow regulator device in the valve system which will be set to cause the Mud Bucket to close at a speed which is suitable for working and safety constraints.

Generally the valve system will be fed by a permanent hydraulic pressure ring main.

Further the device may be operated by a pneumatic system.

Further modifications and improvements may be incorporated without departing from the scope or spirit of the invention herein intended.

Claims (2)

Claims

1. A mud bucket comprising a can, the can being spilt longitudinally into two sections, the sections being hinged together to cooperate in a scissor like action and each section being associated with a respective end of one or more hydraulic cylinders operable between an extended position and a retracted position, wherein when the cylinder is in an extended position the sections are caused to be closed together and when the cylinder or cylinders are in a retracted position, the sections are caused to be open.

2. A mud bucket as claimed in Claim 1 wherein the cylinders are hydraulically activated.