(i) Spring-loaded relief valves of types meeting the provisions of the ASME Unfired Pressure Vessel Code.
(ii) Pilot-loaded back-pressure regulators used as relief valves, so designed that failure of the pilot system or control lines will cause the regulator to open.
(iii) Spring loaded diaphragm-type relief valves.
(iv) A monitoring regulator installed in series with the primary pressure regulator.
(v) A series regulator installed upstream from the primary regulator, and set to continuously limit the pressure on the inlet of the primary regulator in accordance with the provisions of 49 CFR 192.201. (vi) An automatic shut-off device installed in series with the primary pressure regulator, and set to shut off in accordance with the provisions of 49 CFR 192.201. This device shall remain closed until manually reset. It may not be used where it might cause an interruption in service to a large number of customers. (4w) Suitable types of protective devices to prevent overpressuring of low-pressure distribution systems include:
(i) A liquid seal relief device that can be set to open accurately and consistently at the desired pressure.
(ii) A series regulator, as described in s. PSC 135.195 (3w) (v).
(iii) An automatic shut-off device, as described in s. PSC 135.195 (3w) (vi).
(iv) A pilot loaded back-pressure regulator, as described in s. PSC 135.195 (3w) (ii).
(v) A monitoring regulator, as described in s. PSC 135.195 (3w) (iv).
(cw) Suitable types of protective devices to prevent overpressuring of gas pressure holders, pipelines and other facilities that might at times be bottle tight include:
(1) Spring-loaded relief valves of types meeting the provisions of the ASME Unfired Pressure Vessel Code.
(2) Pilot-loaded back-pressure regulators used as relief valves, so designed that failure of the pilot system or control lines will cause the regulator to open.
PSC 135.195 HistoryHistory: Cr. Register, October, 1999, No. 526, eff. 11-1-99; corrections made under s. 13.93 (2m) (b) 7., Stats., Register February 2004, No. 578; correction made under s. 13.92 (4) (b) 7., Stats., Register February 2011 No. 662. PSC 135.197PSC 135.197 Control of the pressure of gas delivered from high-pressure distribution systems additions [49 CFR 192.197]. After 49 CFR 192.197(c), insert: (dw) The service regulator shall be of a type that is capable under normal operating conditions of regulating the downstream pressure within the limits of s. PSC 134.23 and of limiting the build-up of pressure under no-flow conditions to 50% or less of the discharge pressure maintained under flow conditions. (ew) In addition to the provisions of 49 CFR 192.197(a) and (b), if the maximum actual operating pressure of the distribution system is greater than low pressure and is equal to or less than 60 p.s.i.g., a suitable protective device shall be installed to prevent unsafe overpressuring of the customer’s appliances should the service regulator fail. These devices may be installed as an integral part of the service regulator or as a separate unit. Some of the suitable types of protective devices to prevent overpressuring of customers’ appliances are: (1) A monitoring regulator.
(2) A relief valve.
(3) An automatic shut-off device.
(fw) Breather vents shall be provided on all service regulators.
PSC 135.197 HistoryHistory: Cr. Register, October, 1999, No. 526, eff. 11-1-99. PSC 135.199PSC 135.199 Requirements for design of pressure relief and limiting devices additions [49 CFR 192.199]. (ew) In addition, the outlet ports shall be insect-proof and consideration shall be given to all exposures in the immediate vicinity including windows or locations where gas can enter confined areas;
(1) Lock the stop valve in the open position. Instruct authorized personnel of the importance of not inadvertently leaving the stop valve closed and of being present during the entire period that the stop valve is closed so that they can lock it in the open position before they leave the location.
(2) Install duplicate relief valves, each having adequate capacity by itself to protect the system and arrange the isolating valves or 3-way valve so that mechanically it is possible to render only one safety device inoperative at a time.
(iw) Precautions shall be taken to prevent unauthorized operation of any valve which will make pressure limiting devices inoperative. This provision applies to isolating valves, by-pass valves, and valves on control or float lines which are located between the pressure limiting device and the system which the device protects. A method similar to s. PSC 135.199 (2) (hw), shall be considered acceptable in complying with this provision.
PSC 135.199 HistoryHistory: Cr. Register, October, 1999, No. 526, eff. 11-1-99; correction in (2) made under s. 13.93 (2m) (b) 7., Stats., Register February 2004, No. 578. 192.206w Pipelines on private right-of-way of electric transmission lines. Where gas pipelines parallel overhead electric transmission lines on the same right-of-way, the company operating the pipelines shall:
(a) Employ blow-down connections and relief valve vents that will direct the gas away from the electric conductors.
(b) Make a study in collaboration with the electric company on the common problems of corrosion and electrolysis, taking the following factors into consideration:
(1) The possibility of the pipeline carrying either unbalanced line currents or fault currents.
(2) The possibility of lightning or fault currents inducing voltages sufficient to puncture pipe coatings or pipe.
(3) Cathodic protection of the pipeline, including location of ground beds, especially if the electric line is carried on steel towers.
(4) Bonding connections between the pipeline and either the steel tower footings or the buried ground facilities or the ground-wire of the overhead electric system.
(c) Investigate the necessity of protecting insulating joints in the pipeline against induced voltages or currents resulting from lightning strikes. The protection can be obtained by connecting buried sacrificial anodes to the pipe near the insulating joints or by bridging the pipeline insulator with a spark-gap or by other effective means.
PSC 135.206 HistoryHistory: Cr. Register, October, 1999, No. 526, eff. 11-1-99; CR 21-049: PSC 135.206 renum. from PSC 135.204 and am. Register March 2022 No. 795 No. 795, eff. 4-1-22. PSC 192.246w Precautions to Avoid Explosions of Gas-Air Mixtures or Uncontrolled Fires During Construction Operations. (a) Operations such as gas or electric welding and cutting with cutting torches can be safely performed on pipelines and mains and auxiliary equipment, provided that they are completely full of gas, or air that is free from combustible material. Steps shall be taken to prevent a mixture of gas and air at all points where such operations are to be performed.
(b) When a pipeline or main can be kept full of gas during a welding or cutting operation, the following procedures are recommended:
(1) Keep a slight flow of gas moving toward the point where cutting or welding is being done.
(2) The gas pressure at the site of the work shall be controlled by suitable means.
(3) Close all slots or open ends immediately after they are cut with tape, or with tape and tightly fitting canvas or other suitable material.
(4) Two openings may not remain uncovered at the same time.
(c) No welding or acetylene cutting shall be done on a pipeline, main, or auxiliary apparatus that contains air if it is connected to a source of gas, unless a suitable means has been provided to prevent the leakage of gas into the pipeline or mains.
(d) In situations where welding or cutting must be done on facilities which are filled with air and connected to a source of gas and the precautions in par. (b) cannot be taken, one or more of the following precautions, depending upon the circumstances at the job are required:
(1) Purging of the pipe or equipment upon which welding or cutting is to be done, with combustible gas or inert gas.
(2) Testing of the atmosphere in the vicinity of the zone to be heated before the work is started and at intervals as the work progresses, with a combustible gas indicator or by other suitable means.
(3) Careful verification before the work starts that the valves that isolate the work from a source of gas do not leak.
PSC 135.246 HistoryHistory: Cr. Register, October, 1999, No. 526, eff. 11-1-99. (1w) Copper pipe shall be joined by using either a compression type coupling or a brazed or soldered lap joint. The filler material used for brazing shall be a copper-phosphorous alloy or silver base alloy. Butt welds are not permissible for joining copper pipe or tubing.
PSC 135.279 HistoryHistory: Cr. Register, October, 1999, No. 526, eff. 11-1-99. (1w) Detection of gouges and grooves. The field inspection provided on each job shall be suitable to reduce to an acceptable minimum the chances that gouged or grooved pipe will get into the finished transmission line or main. Inspection for this purpose just ahead of the coating operation and during the lowering in and backfill operation is required.
PSC 135.307 HistoryHistory: Cr. Register, October, 1999, No. 526, eff. 11-1-99. (fw) Due primarily to climate conditions, gouges, grooves, notches, and dents have been found to be an important cause of steel pipe failures and an attempt shall be made to prevent or eliminate harmful defects of this nature. Section 192.309 (b) pertains to transmission lines and mains intended to operate at hoop stresses of 20% or 40% or more of the specified minimum yield strength. However, applicable portions of these paragraphs shall apply to facilities intended to operate below this hoop stress level.
PSC 135.309 HistoryHistory: Cr. Register, October, 1999, No. 526, eff. 11-1-99. PSC 135.319PSC 135.319 Installation of pipe in a ditch additions [49 CFR 192.319]. (aw) This includes grading the ditch so that the pipe has a firm, substantially continuous bearing on the bottom of the ditch. When long sections of pipe that have been welded alongside the ditch are lowered in, care shall be exercised so as not to jerk the pipe or impose any strains that may kink or put a permanent bend in the pipe.
(3w) If there are large rocks in the material to be used for backfill, care should be used to prevent damage to the coating or pipe by such means as the use of rock shield material, or by making the initial fill with rock free material to a sufficient depth over the pipe to prevent damage.
(4w) Where flooding of the trench is done to consolidate the backfill, care shall be exercised to see that the pipe is not floated from its firm bearing on the trench bottom.
(cw) The provisions of 49 CFR 192.319(a) shall also apply to mains operating at less than 20% of the SMYS. PSC 135.319 HistoryHistory: Cr. Register, October, 1999, No. 526, eff. 11-1-99. PSC 135.321PSC 135.321 Installation of plastic pipe additions [49 CFR 192.321]. (fw) The casing pipe shall be reamed and cleaned to the extent necessary to remove any sharp edges, projections, or abrasive material which could damage the plastic during and after insertion. That portion of the plastic piping which spans disturbed earth shall be adequately protected by a bridging piece or other means from crushing or shearing from external loading or settling of backfill. Care shall be taken to prevent the plastic piping from bearing on the end of the casing.
(jw) Care shall be exercised to avoid rough handling of plastic pipe and tubing. It shall not be pushed or pulled over sharp projections, dropped or have other objects dropped upon it. Caution shall be taken to prevent kinking or buckling, and any kinks or buckles which occur shall be removed by cutting out as a cylinder.
(kw) Changes in direction of plastic piping may be made with bends, tees or elbows under the following limitations:
(1) Plastic pipe and tubing may be deflected to a radius not less than the minimum recommended by the manufacturer for the kind, type, grade, wall thickness and diameter of the particular plastic pipe or tubing used.
(2) The bends shall be free of buckles, cracks, or other evidence of damage.
(3) Changes in direction that cannot be made in accordance with 192.321 (kw) (1) shall be made with elbow-type fittings.
(4) Miter bends are not permitted.
(Lw) Plastic piping shall be laid on undisturbed or well compacted soil. If plastic piping is to be laid in soils which may damage it, the piping shall be protected by suitable rock free materials before back-filling is completed. Plastic piping shall not be supported by blocking. Well tamped earth or other continuous support shall be used.
PSC 135.321 HistoryHistory: Cr. Register, October, 1999, No. 526, eff. 11-1-99; CR 21-049; renum. 135.321 to (1), (2) and am. Register March 2022 No. 795, eff. 4-1-22. (ew) Casing requirements of highway authorities shall be followed; however, construction type shall not be any less than provided by 49 CFR 192.323. PSC 135.323 HistoryHistory: Cr. Register, October, 1999, No. 526, eff. 11-1-99.