TRIC Training Log: 09-23-04 Client: Plumbing MD, Davis, CA Job: Residence, house to city cleanout in service alley Pull: 65’ / upstream / 4” SDR17 / bursting 4” VCP & AC
We at TRIC Tools have specific requirements for the use and maintenance of our equipment with regard to safety and efficiency on the job. Our written and verbal recommendations coincide with safety regulations set by local, state, and national government agencies. Our clients may have standards over and above industry regulations. However, the safety equipment, apparel, and operating procedures demonstrated by our clients in this presentation may or may not comply with above mentioned government regulations.
Facing pipe surfaces: Place pipe in jig, and leave about 1” of pipe extending beyond clamps (loosely closed). Align pipe sections, using wood blocks or other solid objects to support and adjust pipe with relation to jig. Tighten clamps, bring ends together, and recheck alignment from all angles before inserting facer. Apply slow, even leverage and watch for full “ribbons” of shaved material.
Trim & Check: Continue facing until trimmer stops in jig. Remove all shavings. This will leave about 1/2” of pipe protruding from clamps. Remove facer, bring pipe ends together, and check alignment again before heating. Be careful not to touch faced surfaces.
Heating: Keep iron set at 450º F. To adjust, unplug iron and turn set screw (near handle, opposite gauge) clockwise to reduce temperature and counterclockwise to increase temperature (1/4 turn at a time). Bring pipe surfaces to meet iron and make complete contact, but use no pressure while heating.
The melt: Watch for about 1/8” of melt-back from iron surfaces. Again, no pressure should be applied during melt. The plastic needs to “soak up” the heat thoroughly and evenly in the fusion surface areas. Any pressure applied while heating dissipates the weld material before surfaces can be joined together and also heats unevenly, resulting in a “cold joint” that is subject to failure.
The joint: Remove heater and bring pipe ends together, using steady and even force until melted material rolls back to form a complete rounded “bead” on either side of the joint. Leave pipe undisturbed until just warm, or about 8–10 minutes for 4” SDR17. (Manufacturer’s cooling times vary for each size of pipe, and facing pressures vary for individual fusion machines. Consult respective literature.)
Entry: Property line, from service alley. Sewer runs next to large tree just upstream from property line cleanout, and one large root (4”–5” diameter) wraps over top of lateral. Single large roots touching existing sewer may not seriously impede bursting head, but they can cause bellies in line as flexible pipe is pushed aside by relatively immobile root.
Preparation: Since root is readily accessible, it is worth the time and trouble to eliminate it before beginning. For most pulls, the majority of the work is setup.
Almost ready: An extra 8”–10” of relatively open digging and cutting assures an unobstructed entry and as even a grade as possible.
Holes 1 and 2: Pipe is fused and readied while tie-in points are exposed. At lower right is a 4” tie-in from garage/laundry across driveway. Once located, tie-in points can be burst before excavation, if job logistics or timing demands it.
Holes 3 and 4: A 2” tie-in is exposed near tree at top of driveway (just behind leaf pile). Pulling pit is further upstream, about 10’–15’ downstream from front door at top of image.
Ready for the cable: In many cases, where laterals are relatively short and straight, the pulling cable can be fed right through the line by hand. More difficult laterals (with steep uphill feed, offsets, bends, root blocks, etc.) require using the duct rodder to pilot the distance first, and then the cable can be taped to the rodder and drawn through the sewer.
Entry: Guide the bursting head into the line to assure the easiest and most direct entry. This may require flexing or bowing the PE pipe to get it in line with the existing sewer. After 4 or 5 feet of travel, the PE pipe will have taken its path and may not need further assistance, other than to keep it clear of pedestrian and/or vehicular traffic.
From the top: Operator should have clear vision of pressure gauge and exiting cable at all times. Pipe entering at other end of pull should also be monitored periodically. Note another 4” tie-in just behind ram at lower left.
Hole #2: Tie-in at base of driveway. Lateral and connecting spur are vitreous clay at this point.
Hole #3: 2” ABS connection from main building. Lateral is asbestos concrete at this point.
Traffic control: Keeping pipe clear of existing cleanout stack, and watching the alley at the same time.
Ideal vantage point: During a pull, the operator should stay out of the pulling pit while the cable is under tension. Also, the clearest perspective of the cable’s travel through the pulley base is from above as shown.
Steady progress: Bursting head is approaching hole #3.
Back at Hole #1: The tree providing all this shade will be undamaged by this trenchless job. (It will also get no further irrigation from the new sewer!)
Hole #3: Asbestos pipe section is pushed upstream and into open pit. This happens more frequently with ABS and PVC plastic lines in softer ground. The blade on the bursting head is needed to split plastic pipe (and to cut bands and couplings).
Bursting revealed: Hardened steel head with blade usually wins the argument. Plastic pipe can be far more stubborn, and may need to be broken by hand if it folds and collects around bursting head as it enters an open pit (or as it approaches the pulley base).
Final inches: Watching the cable as it crosses the threshold of the resistance plate and pulley base.
Clear view: Keep the pulley area free of bursting debris, which is especially prevalent towards the end of a pull, and which often immediately precedes the clevis.
End of the line: When clevis sheath is just visible inside pulley housing, it’s time to stop. If sheath is brought under pulley wheel, it will be bent and require new termination. Now it’s time to detension the cable and remove the resistance plate and use the extender cage.
Extender cage: Release the ram, and remove the resistance plate from pit. Extender cage (at right) is positioned against pulling wall, straddling cable. Pulley base fits into recessed end of cage to allow an extra 18”–24” of pull, to expose bursting head. (Note that some pulling pits are too small to accommodate the cage, and wood cribbing must be used instead.)
On call: Plumbing MD has added a new trenchless service to its specialized fleet.