Wiper Cementing Plug

Reasons for Using Cementing PlugsRemove mud sheathSeparate cement and MudPrevent over displacementSurface indicationPressure test casing

Surface indication when top plug bumps & cement job is complete.Pressure test casing - customers in North Sea & Gulf Coast are pressure testing casing immediately after bumping top cementing plug. Pressures up to 10,000 psi are being applied - requires high pressure plugs & high strength floating equipment.HP plug available in 9-5/8, 10-3/4, & 13-3/8 casing sizes with non-rotating profiles.Testing casing while cement is still in fluid state prevents micro annulus.

Five Wiper Cementing PlugsAvailable with:aluminum insertsplastic insertsnon-rotating (NR) plastic inserts350 psi rupture diaphragm in bottom plugsSurface release or sub-surface release (SSR)Compatible with water-based or oil-based muds

Surface indication when top plug bumps & cement job is complete.Pressure test casing - customers in North Sea & Gulf Coast are pressure testing casing immediately after bumping top cementing plug. Pressures up to 10,000 psi are being applied - requires high pressure plugs & high strength floating equipment.HP plug available in 9-5/8, 10-3/4, & 13-3/8 casing sizes with non-rotating profiles.Testing casing while cement is still in fluid state prevents micro annulus.

NR Cement Plug SystemReduces drillout timePDC drillable350 psi rupture diaphragm Use with NR float collarAll plastic inserts

Patented system - pioneered by HES.Use non-rotating (NR) plugs with NR float collar.Matching teeth profile on Super Seal II NR Float Collar.Teeth profile locks plugs to NR float collar to prevent rotation of plugs during drillout.

Top & Bottom Plugs with NR Float Collar

NR Cement Plugs

PDC bit shown for drillout.

Pumping Cement without Cement PlugsMuch cement contaminationNo surface indication of cement placement

Displacement fluid washes portion of mud sheath from casing behind cement, leaving outside of shoe joint.No fluid control.

Pumping Cement with Top Plug OnlyTop plug wipes mud sheath from casing IDSeparates cement from displacement fluidSurface indication when cement placement is completeRequire additional shoe track length

Top cement plug wipes mud sheath from casing ID ahead of plug.Wipe mud accumulates ahead of top plug.When top plug is bumped, volume of accumulated mud ahead of plug fills shoe joint & portion of annulus outside shoe joint.Results in wet shoe - no cement in annulus opposite shoe joint.Requires squeezing of the shoe joint before drilling ahead.

Accumulated Mud Volume Ahead of Cement PlugFill up per 1,000 ft. casing

This slide shows the amount (in feet) of 5-1/2 or 7 casing that will be filled by a mud sheath of 1/16,1/32, or 1/64 thick wiped from the ID of the casing by a five wiper cement plug per 1000 feet of casing. This chart stresses the importance of pumping a bottom cementing plug ahead of the cement slurry during cementing operations.Note that valves in table are per 1000 of casing.Regardless of thickness of mud sheath, chances on any depth well that accumulated mud volume will exceed length of shoe joint - placing mud in shoe joint & in the annulus opposite the shoe joint.

Pumping Cement with Top & Bottom PlugsPreferred methodBottom plug wipes mud sheath from casing IDSurface indication when cement placement is completeMaximum cement/mud separation

Using bottom plug, majority of mud sheath on ID of casing is displaced in the annulus leaving good cement opposite the shoe.Top & bottom plugs are recommended unless mud system contains large volumes of lost circulation material or cuttings.

Polycrystalline Diamond Compact Bits (PDC)Soft medium formationsImproves rate of penetrate (ROP)Longer service life

PDC bits are extremely aggressive bits.ROP - rate of penetration.Fewer bit trips with PDC bits - more feet of hole drilled per bit trip to save customer costs.Fewer bit trips, less potential well blowouts.Drillout of float equipment & plugs requires lower bit weights on equipment & higher RPM.

Concave PDC Bit

Shows polycrystalline diamonds (synthetic diamonds) in steel matrix.Many different shapes & designs for different formations.

Illustrates aggressive nature of PDC bits

Illustrates aggressive nature of PDC bits - shows large chunks of rubber from 5-wiper plug around bit.Need to run low bit weight at high RPM to prevent drilling large pieces of material.

Surface indication when top plug bumps & cement job is complete.Pressure test casing - customers in North Sea & Gulf Coast are pressure testing casing immediately after bumping top cementing plug. Pressures up to 10,000 psi are being applied - requires high pressure plugs & high strength floating equipment.HP plug available in 9-5/8, 10-3/4, & 13-3/8 casing sizes with non-rotating profiles.Testing casing while cement is still in fluid state prevents micro annulus.

Surface indication when top plug bumps & cement job is complete.Pressure test casing - customers in North Sea & Gulf Coast are pressure testing casing immediately after bumping top cementing plug. Pressures up to 10,000 psi are being applied - requires high pressure plugs & high strength floating equipment.HP plug available in 9-5/8, 10-3/4, & 13-3/8 casing sizes with non-rotating profiles.Testing casing while cement is still in fluid state prevents micro annulus.

Patented system - pioneered by HES.Use non-rotating (NR) plugs with NR float collar.Matching teeth profile on Super Seal II NR Float Collar.Teeth profile locks plugs to NR float collar to prevent rotation of plugs during drillout.

PDC bit shown for drillout.

Displacement fluid washes portion of mud sheath from casing behind cement, leaving outside of shoe joint.No fluid control.

Top cement plug wipes mud sheath from casing ID ahead of plug.Wipe mud accumulates ahead of top plug.When top plug is bumped, volume of accumulated mud ahead of plug fills shoe joint & portion of annulus outside shoe joint.Results in wet shoe - no cement in annulus opposite shoe joint.Requires squeezing of the shoe joint before drilling ahead.

This slide shows the amount (in feet) of 5-1/2 or 7 casing that will be filled by a mud sheath of 1/16,1/32, or 1/64 thick wiped from the ID of the casing by a five wiper cement plug per 1000 feet of casing. This chart stresses the importance of pumping a bottom cementing plug ahead of the cement slurry during cementing operations.Note that valves in table are per 1000 of casing.Regardless of thickness of mud sheath, chances on any depth well that accumulated mud volume will exceed length of shoe joint - placing mud in shoe joint & in the annulus opposite the shoe joint.

Using bottom plug, majority of mud sheath on ID of casing is displaced in the annulus leaving good cement opposite the shoe.Top & bottom plugs are recommended unless mud system contains large volumes of lost circulation material or cuttings.

PDC bits are extremely aggressive bits.ROP - rate of penetration.Fewer bit trips with PDC bits - more feet of hole drilled per bit trip to save customer costs.Fewer bit trips, less potential well blowouts.Drillout of float equipment & plugs requires lower bit weights on equipment & higher RPM.

Shows polycrystalline diamonds (synthetic diamonds) in steel matrix.Many different shapes & designs for different formations.

Illustrates aggressive nature of PDC bits - shows large chunks of rubber from 5-wiper plug around bit.Need to run low bit weight at high RPM to prevent drilling large pieces of material.