Frequently Asked Questions

1. Available in 2″ and 3″ connection sizes
2. Interchangeable with Demco® style
3. Pressure ratings range from 1000 PSI to 7500 PSI
4. Provides protection of personnel, environment, and property in over-pressure event
5. Shear pins available in different colors to help select correct shear pressure
6. Re-usable valve – if an over-pressure event occurs, correct the pressure problem and insert a new shear pin

Drill pipe float valves are designed and used for flow control and pressure control. A drill pipe float valve is a check valve that keeps drilling mud, air, foam or mist from traveling back up the drillstring. Float valves installed directly above the bit provide the best protection against backflow of drilling fluid, which has suspended rock cuttings and milled steel pieces, which could clog the bit, and damage the tools above the bit.

When it is time to change a bit or modify the BHA (bottom hole assembly) all of the drillstring needs to be removed from the well. It is common to remove 90-foot sections of pipe (three 30 foot pipes), to be stacked vertically as they are pulled out of the well. The drillstring is separated into sections by unscrewing connections. If there is drilling mud in the top of the drillstring when breaking a connection this can spill mud onto the rig floor, and become a safety and environmental problem. When the drillstring is raised, the float valve opens to allow the mud to flow back down into the well, enabling breaking of a “dry” connection.

Working automatically and redundantly in the drillstring, the float valve assists other safety equipment to control unexpected and excessive pressures that would otherwise travel to the surface through the ID of the drillstring. Float valves can be a vital and supportive tool in the overall well control plan.

Blue is the signature color of a Drillmax drill pipe float valve. The blue Xylan coating of Drillmax’s float valve adds erosion and corrosion protection, and is only one of the value added benefits of “the blue float valve”.

1. Interchangeable with Baker®/Forum style
2. One-piece cage design for improved reliability
3. Cages have increased wall thickness of 20% – 25%
4. Made from ductile iron or carbon steel alloys
5. Carbon steel alloys heat treated to hardness levels at or below 22 Rockwell C for H2S applications
6. Xylan® Fluoropolymer coating on all cages
7. Higher impact properties, resulting in longer life
8. Available with corrosion resistant Inconel® springs
9. Repair Kits available in rubber and metal

Drillmax makes 11 types (models) of float valves. There are 10 sizes in plunger type, and 9 sizes in flapper type. Each one of these is available in 3 dressings – for standard, H2S and high temperature services.

1. Interchangeable with Demco® style
2. In-line field repairability
3. 5000 PSI working pressure sizes 2″, 3″, 4″, and 5″x4″
4. 7500 PSI working pressure sizes 2″x3″, 4″, and 5″x4″
5. Bi-directional drop tight sealing
6. Available standard, H2S sour gas, and high temperature services
7. Rising stem protects threads from fluids
8. Sight lens included on larger sizes
9. Double acting threads allow opening and closing the gate with ease