Drilling Fluid Loss Control
Drilling Fluid Loss Control (FLC) – An important characteristic of Gilsonite is its softening-point temperature. In oil-base muds, it is used as a fluid-loss control agent. Being a hydrocarbon, it is naturally wetted by the oil. In water-base muds, it is used as a shale-stabilizing additive and is difficult to evaluate unless tested at or above its softening point. As a hydrocarbon, the powder must be coupled to water by using a glycol or similar water-wetter.
As an integral component of premium drilling fluid products, Gilsonite actively improves drilling efficiencies while reducing costs and minimizing the HSE impact associated with most drilling fluid additives.
For many years, Gilsonite has been used in the oilfield as an additive in drilling fluids. Gilsonite’s unique properties make it important for many oil field drilling fluid products and the recent boom in oil and gas development has increased demand. Gilsonite, in various grades and formulations, has been used to combat borehole instability problems, provide lubricity, especially in highly deviated holes, and more recently as a bridging agent to combat differential pressure sticking and provide a law invasion coring fluid.
When Gilsonite is added to oil- and water-based drilling fluids, it partially melts or deforms, plugging off micro-fractures in the rock and smearing the inside of the wellbore to make a tight, tough filter cake that prevents fluid loss. The dissolved Gilsonite also increases drilling fluid viscosity, providing lubrication, and together with the sealing off and stabilization of problem rock around the well bore, helps prevent the drill pipe from getting stuck in the well.
It has been well documented that appropriately formulated Gilsonite products can minimize hole collapse in formations containing water-sensitive, sloughing shales and reduce stuck pipe problems by forming a thin wall cake and an inter-matrix filter cake. Gilsonite minimizes the occurrence of stuck pipe and stuck logging tools by thoroughly sealing permeable formations – even in zones with a highly overbalanced pressure differential – and improving filter cake lubricity.
Gilsonite products are currently being widely used in water based (helps minimize hole washout by stabilizing troublesome shales, and seals off highly permeable sands while reducing torque and drag), oil based (The addition of Gilsonite to oil well cements reduces slurry weight without loss of compressive strength and acts as an effective bridging and plugging agent to seal fractures in weak formations while cementing) and synthetic based mud systems worldwide.
Blended Gilsonite has proved to be very effective in all water-based systems. Gilsonite is also used in cementing fluids as a lost-circulation material due to its plugging and binding properties, and as a slurry density reducer in some specialty cementing Fluid
In numerous grades and formulations, Gilsonite has been utilized to fight borehole instability complications, offer lubricity particularly in greatly diverged holes, and lately, as a bridging instrument to contest differential pressure sticking and deliver a less invasive coring fluid. With a unique blend of strength, flexibility, bonding and high-temperature capability, asphaltum adds properties that increase performance in cementing and drilling fluids in a way no other single additive can.
Gilsonite, the recognized industry standard for filtration control, is equally effective at controlling lost circulation and improving wellbore stability, drilling efficiencies, wellbore stability, filter cake development and more.
Gilsonite, in a range of softening points and particle sizes, is a standard ingredient in oil-based drilling muds used in shales and other difficult geological formations. The addition of specially-treated Gilsonite to water-based drilling fluids helps minimize hole washout by stabilizing troublesome shales, and seals off highly permeable sands while reducing torque and drag.
The addition of Gilsonite to oil well cements reduces slurry weight without loss of compressive strength and acts as an effective bridging and plugging agent to seal fractures in weak formations while cementing. also Gilsonite use in Mud drilling according to FLC ” Filtrate Loss Control ” or ” Fluid Loss Control ” in oil base mud .
Functions of Drilling Fluid loss control (FLC)
- Remove cuttings from the well.
- Control formation pressure.
- Suspend and release cuttings.
- Suspend and release cuttings.
- Seal permeable formations.
- Maintain wellbore stability.
- Minimize reservoir damage.
- Cool, lubricate, and support the bit and drilling assembly.
- Transmit hydraulic energy to tools and bit.
- Ensure adequate formation evaluation.
- Control corrosion
- Facilitate cementing and completion.
- Minimize impact on the environment.
- Prevent gas hydrate formation.
Gilsonite provides all of these benefits:
- Provides wellbore strengthening matrix
- Controls fluid loss and seepage
- superior shale stabilization
- Prevents lost circulation
- Strengthens the wellbore to increase wellbore stability
- Minimizes differential sticking
- Reduces or eliminates lost circulation
- Promotes effective filter cake development
- Performs in oil- and water-based drilling muds
- Performs in HP/HT environments
- Minimizes HSE risks
Proven to strengthen the wellbore HP/HT wells, shales and underpressured zones require specialized drilling fluids and wellbore-strengthening techniques. Adding Gilsonite to an OBM, SBM or WBM strengthens the well by: