toll free: 1-888-712-5595

fax: 956-712-4788

DESI SEAL MCT-500™ Medium

(Mud Circulation Treatment - Medium Grade Cellulose Material)

View Material Safety Data Sheet


MCT-500™ (Mud Circulation Material) is primarily used for control of partial or total losses in water, oil, or brine fluids. MCT-500™ is an unique combination of granular and fibrous cellulose materials sized to compliment MCT-1000™ and cover size ranges above those covered by the smaller MCT-1000™ designation.

A combination of MCT-1000™ and MCT-500™ will solve loss problems from seepage to total losses. The unique characteristics of MCT-500™ allow it to seal formations while not damaging down-hole tools.


  • Seals micro-fractures
  • Helps prevent loss circulation or heals it
  • Minimal rheological effect on fluids
  • Compatible with water, oil, and brine fluids
  • Minimizes formation damage from fluid invasion
  • Easily removed from productive formations
  • Thermally stable
  • Environmentally safe
  • Bio-degradable and non-toxic
  • Non-damaging to down-hole tools

General Application Procedures

Seepage Loss (10-20 bbls/hr, or greater)

In cases where seepage is in excess of 10-20 bbls/hr, a pill consisting of 60% MCT-500™ and 40% MCT-1000™ is recommended. Pills volume should cover a minimum of 500' off open hole. Additional pills should be pumped as hole conditions dictate.

Lost Circulation

Mix DESI SEAL™ through the chemical hopper in a pill containing 60% MCT-500™ and 40% MCT-1000™. Fluid density will determine the total concentration that can be mixed. Total concentrations of 25-65 ppb are common. It is advisable to spot the pill across the loss zone, then pull up into the last casing. The pill mixture may be squeezed (applying 50-100 psi) into formation. After circulation is regained a MCT-1000™ / MCT-500™ sweeping program is recommended to maintain the integrity of the seal during drilling operations.

Differential Sticking Prevention

Prior to drilling depleted zone add 2-4 ppb MCT-1000™ to the system. Mix a pill containing 8-15 ppb MCT-1000™ and 8-15 ppb MCT-500™. Sweep the hole as new sands are drilled and every 4-6 hours depending on hole conditions. Sweep the hole prior to tripping, logging, or running casing.

Physical Characteristics

Form: Solid
Odor: Minimal
Color: Light to Dark Brown
Solubility (H2O): Minimal
Solubility (Oil): Minimal

Packaging: 25 pound bags, 50 per pallet, shrink-wrapped