Tube and Tubing

Obj 1- types, designations, pressure ratings

  • Flaring: spreads end of tubing

  • Hard temper tube: recommended for exposed lines. Rigid tubing supports sagging and deflection

  • Soft temper tube: buried lines or laid in floors, more flexible. Allows tube to move if ground movement occurs.

    Copper pipe, tube, tubing

  • Copper is refined to 99.7% purity before made into seamless pipe

  • Main adv is malleability, ductility, corrosion resistance

  • Smoother surface so its flow capacity is 20% greater than steel or iron pipe.

  • Main disadv is the high coefficient of expansion

  • Red brass: 85% copper and 15% zinc

    • better corrosion resistance

  • Yellow brass: 66% copper and 34% zinc

    • harder wearing

    • Standard valves, faucents, taps

  • Brass is copper and zinc

  • Brass has higher coefficient of expansion than copper.

  • Bronze is copper and tin

  • Most bronze pipe is 90% copper and 10% tin. Mainly used for underground water service.

  • Bronze has higher coefficient of expansion than copper but not brass.

  • Copper is an extremely good conductor of heat- good in heat exchanger but not good if heat conservation is necessary.

  • 3 designations of copper:

    • Copper pipe:

      • same as steel pipe. Comes 12” up to for ID, 14” and over is sized by OD NPS.

      • Standard, XS, XXS

    • Copper tube:

      • thinner wall than copper pipe

      • Specified by approx ID in NPS

    • Copper Tubing:

      • thin walls 0.028” (1/8 to 1/2” tubing) or 0.032” (1/8 to 3/4” tubing) sized by OD

      • Soft tempered up to 100ft lengths

  • Copper colour codes:

    • Type K - Green

      • thickest wall

      • 1/4” to 12”

      • Hard temper up to 12 or 20’

      • Soft temper up to 100’

      • Water service in coils at 66’

    • Type L - Blue

      • medium wall thickness

      • Same sizes as type K

      • Water service up to 60’ lengths

    • Type M - Red

      • most commonly used

      • This tubing should not be bent

      • 1/4” to 12” and lengths 12’ to 20’. Hard temper only

    • Type H - White

      • thin walls

      • Especially hot water heating systems

      • No longer available but came in sizes 1/2, 3/4 and 1” in 12’ sections

    • Type DWV - Yellow

      • not pressure rated, drainage only

      • Above ground inly

      • 1 ¼ to 6” sizes and 12 or 20’ lengths in hard temper only


Obj 2 fitting types and joining techniques

  • cast brass: poured molten brass, rough finish

  • Barstock: finished brass material

  • Wrought copper: pressure and force and heating in a die

  • Bronze: used alot of compression or flare fittings underground

  • 4 joint types:

    • soldering type:

      • sometimes referred to as streamline (mfg name)

      • DWV version available with smaller cup, pressure eated fittings have a bigger cup.

    • Compression type:

      • typically barstock brass, 2 styles: standard and long

      • Ferrule type is referred to as flareless or sleeve type.

      • Nuts are not interchangeable! Ensure all are same type.

      • Uses 2 sealing sleeves or collets. 1/16 to 1”sometimes called tylok or swagelok.

      • High pressure version has serrated edges and can go up to 10,000 psig, on 1/8 × 0.032 tubing. This fitting available in 1/8 to 1/2”.

    • Flared:

      • most commonly used version is the flared 45 degrees.

      • Usually mfg from brass.

      • Flared creates a stronger connection than soldered or compression

      • Need at least type L or soft tubing.

      • SAE made 3 design standards:

        • SAE 37degree

        • SAE 45degree(most commonly used version)

        • Inverted flare

      • If using flare on gas, the nut needs to be forged.

      • Flared can be single flare or double flared. Double flared is higher pressure rated and used in hydraulic lines often.

        • recommended double flared if tubr walls are thin “thin-off”

    • Press Connect:

      • relies on copper malleability, relies on sealing capability of a elastometric gasket seal

      • Rated 0 to 300 psig, -40F to 284F.


    Obj 3 - identify application and mfg specs pertaining to joining methods:

  • Applications:

    • Plumbing:

      • water service lines:

        • soft temper type K and L for resi underground.

        • Usually joined by compression or flared

      • hot water/distrib:

        • K, L or M,

        • Usually soldered

      • DWV:

        • special DWV tube non pressure rated

        • 1 ¼ to 6” but to 3” is usually max

        • K, L or M can be used too but DWV is cheaper

        • If underground waste and rain then use K or L

        • Usually soldered

    • Heating:

      • high temps speed up corrosion, ehich is why copper is preffered for heating

      • L or M but K can be used cor more severe application

      • Hard temper for riser, soft temper for stub ins

      • Plan 1/8” movement per 10ft rub for each 100F temp chabge plan via expansion or slip joints

    • Hot water/Hydronic:

      • type M is hard temper inly, so use K or L if soft temper needdd

    • Radiant heating:

      • type L most common

    • Industrial Heating or steam :

      • K or L

      • Low pressure might us type M (<15psig)

      • If >250F then silver brazed.

    • Gas Fittings:

      • K or L, or G if above ground up to 1 1/4” (G type is just a PVC coated copper tube)

      • Silver brazed joints

  • Specialized Applications

    • Oxygen Tubes

      • Either Type K or L.

      • CSA Z305 has info on medical gas installs

      • Tube lengths are steam or chemical cleaned and capped for shipping.

      • tube should be degreased to prevent fires.

      • Copper to copper - use phosphorous brazing with no flux. Dissimilar metals you may use flux.

    • Oil Burners

      • Soft temper K or L. Hard temper can also be used for neat appearance.

      • Flared joints typically used.

    • Fire Sprinklers

      • Building code standards 13, 13D, 13R guidelines for install

      • NFPA permits type M, L, K copper sizes down to 3/4”.

      • Brazing, soldering, epoxy adhesives.


Obj 4 - Tube bending process

  • Both annealed and bending temper tube can be bent with hand benders. Usually bending soft tubing above 1” becomes difficult though.

  • Type L or K soft and hard copper are designed for bending. You can bend soft copper by hand but rigid copper needs tube benders.

  • Types of Benders:

    • Spring benders:

      • protect tube from being reduced at the size of bend.

      • not designed for consistent radius each time

      • small diameters only. If pushing past limits, it will kink tubing

    • Gear Benders:

      • Provides mechanical advantage

      • Typically type K or L tube, usually most reliable for 1/2” to 1” tube

      • Usually max bend u can do is 180deg.

      • Lever type or mechanical type

    • Lever and Mechanical Benders:

      • Lever type - relies on operator strength, usually good up to 5/8” for hard temper tube.

      • Mechanical type - uses gear advantage and ratchet, usually good for 3/4” L tube.

      • Benders are handheld

      • Each bender is only made for 1 specific tubing size.

  • If bending a 90, ensure your reference material is Left or Right - if using right, you line your measurement to R while the 2× 0’s are aliged. If from the left align the “90” or the L. Bend until the 0 gets to the 90.

  • If bending 45, align the measurement mark to the 45 deg mark, measured reference length doesnt matter if it’s on the left or right. Bend until the 0 gets to 45 deg mark.