Heavyweight Heavy-Duty Shielded No Hub Couplings
VERSATILE AND ADAPTABLE
Since 1991, Mission has been manufacturing the HEAVYWEIGHT Coupling, in turn supplying the plumbing and mechanical industry with the highest performance in heavy-duty couplings aboveground or underground. All HEAVYWEIGHT Coupling materials are sourced and manufactured here, in the U.S.A.
RIGID JOINT + DEFLECTION
HEAVYWEIGHT Couplings easily adapt to deflection and recovery of underground applications without pulling apart
RESISTS INTERNAL PRESSURE
Counteracts “hydraulic jump” or hydrostatic pressure surges in multi-story aboveground commercial and residential structures
Tapered shield ends reduce friction and prevent injury from sharp edges = simple and safe installation
- Vertical installations where blockages can build-up pressure
- Fire-resistant pipe systems (e.g. cast iron)
- Noise/vibration-free pipe systems (e.g. multiple dwellings)
- Soil expansion or contraction from temperature changes
- Seismically active areas
- Highly corrosive environments
- Improperly backfilled trench beddings
- High groundwater tables
Modern pipe systems are not all designed to withstand increased internal hydrostatic pressure. This is especially common in multi-level commercial projects with subterranean garages. Increased internal demands can cause excessive pressure throughout the system, resulting in “hydraulic jump”. (A surge in the pressure at any change of direction, in particular at the base of the stack.)
Hydraulic jump is the number one reason no hub pipe systems fail. System failures can lead to potential health risks, property and structural damage.
Mission’s HEAVYWEIGHT Couplings are designed to withstand increased hydrostatic pressure, eliminating the inherent dangers of hydraulic jump.
Underground pipe systems present special problems. Corrosion, earth movement and infiltration/exfiltration can occur without detection. HEAVYWEIGHT Couplings provide a more rigid joint that will allow some deflection and recovery, without pulling apart.
Advantages of using the HEAVYWEIGHT Coupling instead of a standard no hub coupling:
The National Bureau of Standards, now known as the National Institute of Standards and Technology (NIST), performed a 14 yearlong evaluation. The tests were initiated in 1970, and data is continually recorded. The compiled data from extensive testing is entitled, The Corrosion Behavior of Selected Stainless Steels in Soil Environments (NMSIR 81-2228). Various soils were selected from 128 test sites, previously evaluated, to represent the range of different corrosive soils throughout the United States.
UNDERGROUND TEST INSIGHTS
TYPE 304 Stainless Steel
- Highly resistant to both pitting corrosions and ground attacks
- No stress corrosion cracking in actual underground applications
- No failures when coupled to zinc, magnesium or iron (steel), in testing stressed dissimilar metals
TYPE 301 Stainless Steel
- Stress cracking in full hard and half hard stainless steel
- Micro cracking after two years in claylike soils
- All half hard specimens coupled to magnesium failed, in testing stressed dissimilar metals
- Two out of six specimens (33%) were not resistant to cracking when coupled to iron.
Historically, mechanical engineers have specified bell and spigot pipe to mitigate underground soil conditions. The two ways to join bell and spigot pipe result in different system performance:
- Rigid (Lead and Oakum)
- Semi-Rigid (Compression-Type Gaskets)
Rigid (Lead and Oakum)
Rigid lead and oakum joints resist increased hydrostatic pressure, but offer limited deflection capabilities. These joints can crack and fail due to earth movement, soil settling or seismic activity.
Semi-Rigid (Compression-Type Gaskets)
Semi-Rigid, Compression-Type Gasket joints do allow some deflection. According to CISPI deflection of 5″ max. on 10′ pipe, which if exceeded, could present both infiltration and exfiltration problems. Moreover, all changes of direction need restraining. These joints vary in radical compression from joint to joint. Inconsistent lubrication application during installation causes these variances.
Mission’s HEAVYWEIGHT Couplings are capable of withstanding hydrostatic pressure changes while maintaining system integrity. These heavy-duty, no hub couplings are cost efficient, simpler to use, and safer to install.
CityCenter Las Vegas is a 16,797,000-square-foot (1,560,500 m2) mixed-use, urban complex on 76 acres (31 ha) located on the Las Vegas Strip in Paradise, Nevada.
Yankee Stadium is located in the Bronx, a borough of New York City. It serves as the home ballpark for the New York Yankees of Major League Baseball (MLB), and the home stadium of New York City FC of Major League Soccer (MLS).
Bank of America Tower (BOAT) at One Bryant Park is a 1,200 ft. (366 m) skyscraper in the Midtown area of Manhattan in New York City. It was the first commercial high-rise to achieve LEED® Platinum Certification.
Bay Adelaide Centre is an office complex in the Financial District of Toronto, Ontario, Canada. The development achieved LEED® Gold status for the project’s environmental sustainability.
Heavy-duty no hub couplings designed to connect cast iron hubless soil pipe and fittings in sanitary and drain waste and vent (DWV) applications. For non-pressure, gravity flow applications only. Sizes 1.5″ to 15″
Multiple Axially Slotted Clamps: Heavy-Duty 304 Series Stainless Steel, Worm Drive (4 or 6)
Gasket: Molded, One-Piece Elastomeric Sealing Gasket
Shield: Heavy-Duty 304 Series Stainless Steel (.0075″ thick)
Increased band tension secures pipe ends, forming a watertight, root-proof seal, impervious to infiltration and exfiltration.
Sealing “O” Rings under each clamp prevent pipe end slippage for a reinforced joint seal.
Stainless steel components combined with significant deflection factor, makes this coupling highly dependable aboveground or underground, and corrosion resistant in a variety of environments.
Expanded stainless steel shield accommodates additional sealing clamps and supplies greater load bearing control between the coupling and surface of the pipe and fitting.
Thicker, wider, corrugated shear band controls load bearing between coupling and pipe surface, opposing shear forces while maintaining pipe alignment.
Independent clamp tightening adapts to different outside pipe diameters. Internal pipe stop ensures proper pipe positioning, reducing noise and vibration.
Molded rubber gasket resists ultraviolet rays, ozone, fungus growth, natural soil erosive properties, and normal sewer gases.
High-quality, molded rubber gasket withstands tension and compression. Synthetic rubbers permit a substantial degree of distortion without change in basic physical resistance.
Flanged rubber gasket helps maintain alignment during installation, and shield’s tapered ends reduce friction and prevent injury from sharp edges. Easy to assemble, disassemble and reuse.
Installs with a pre-set torque wrench calibrated: 80 in/lbs.
Seekonk Torque Wrench:
80 in/lbs. with .3125″ hex head screw