2.3.1

1. 2.3.1 Identifying Equipment & Procedures Used on Propane Transports Most of the propaneused by residential, commercial and industrial customers is transported to bulk plants or directly to large customer accounts by tractor-trailer transports. • In this module, you will learn to: • Identify applications and features of propane transports • Maintain and operate pumps and associated circuits on transports • Identify functions of emergency discharge control systems and safety features of transports • Identify U.S. DOT cargo tank labeling and markings

2. Features of Propane Transports In U.S. Department of Transportation regulations in some cases use the term “transport” to refer to any bulk cargo tank motor vehicle, regardless of its size or configuration. DOT regulations also call bulk delivery vehicles cargo tank motor vehicles (CTMVs). In the propane industry, transports are understood to mean tractor/trailer combination vehicles that have semi-trailers that are cargo tanks. “Metered delivery service” means an unloading operation conducted at a metered flow rate of 100 gallons per minute or less through an attached delivery hose with a nominal inside diameter of 1.25 inches or less. The majority of propane transports are not equipped with liquid meters and small diameter delivery hoses, and are not used in metered delivery service.

3. Features of Propane Transports Regardless of their size, application, or devices used to control their operation, all transports have basic features and equipment in common. Figure 1. Cargo Tank Motor Vehicle

4. Features of Propane Transports Cargo Tank Figure 2. Typical Features of Transport Cargo Tanks

5. Features of Propane Transports Data Plate Name Plate May be combined in a single data plate. Specification Plate Figure 3. Cargo Tank Data Plates

6. Features of Propane Transports Data Plate Figure 4. MC 331 Cargo Tank Data Plate

7. Features of Propane Transports • Cargo tanks have the following openings for connections: • Liquid level gauges • Temperature well • Pressure gauge • Cargo tank fill and equalizing connections • Cargo tank withdrawal connection • Pressure relief valve(s)

8. Features of Propane Transports Rotary Gauge Figure 5a. Rotary Gauge

9. Features of Propane Transports Rotary Gauge Figure 5b. Cross Sectional View of Rotary Gauge

10. Features of Propane Transports Rotary Gauge Figure 6. Rotary Gauge Face

11. Features of Propane Transports Float Gauge Figure 7a. Float Gauge Figure 7b. Cargo Tank 50% Liquid Filled

12. Features of Propane Transports Fixed Liquid Level Gauges Figure 8a. Fixed Liquid Level Gauge Outage Figure 8b. Cross Sectional View in Cargo Tank

13. Features of Propane Transports Thermometer & Pressure Gauge Fixed maximum liquid level gauges installed in pressure cargo tanks are used each time the tank is filled. The pressure gauge and thermometer are used to check the load of gas in the cargo tank, while the thermometer and scales on the liquid level gauge are used to determine the maximum permitted filling level. One method of checking the accuracy of rotary and float gauges is to fill the cargo tank with propane until a white mist vents out of the fixed maximum liquid level gauge. The rotary and float gauges should indicate the same percentage of tank volume as indicated by the fixed maximum liquid level gauge if you have a liquid temperature near 40° F.

14. Features of Propane Transports Fixed Liquid Level Gauges Figure 9. Fixed Maximum Liquid Level Gauge

15. Features of Propane Transports Temperature Well & Thermometer Figure 10. Temperature Well Figure 11. Dial Indicating Temperature Gauge

16. Features of Propane Transports Temperature Well & Thermometer Figure 12. Thermometer, Pressure Gauge And Fixed Liquid Level Gauges

17. Features of Propane Transports Loading, Unloading and Vapor Equalizing Connections The fill and equalizing connections in propane cargo tanks vary according to their applications for metered or un-metered delivery service. The vapor equalizing connections always contain a riser inside the tank that extends to the vapor space in the cargo tank. The fill connection in most cargo tanks connects to a riser used to "spray fill" the tank. When piping is installed, even though the fill connection and the connected bypass piping will contain liquid propane, the opening at the outside of the cargo tank must be permanently labeled either “VAPOR” or “Spray-Fill” because the piping ultimately communicates with the vapor space of the cargo tank due to the spray fill feature.

18. Features of Propane Transports Loading, Unloading and Vapor Equalizing Connections Figure 13. Schematic Drawing of Transport Cargo Tank Loading, Unloading and Vapor Equalizing Connections

19. Features of Propane Transports Loading, Unloading and Vapor Equalizing Connections Figure 14b. Rear Loading & Unloading Valve Connections Figure 14a. Bottom-Center Loading & Unloading Valve Connections

20. Withdrawal Connection Figure 15. Internal Valves

21. Position A: When the operating lever is in the closed position, tank pressure (liquid or vapor) holds the main and pilot valves in the closed position. Figure 15a. Valve Closed (Position A) Withdrawal Connection

22. Position B: When the operating lever is moved to the open position, the cam moves the valve stem upward, opening the pilot valve orifice. Tank pressure bleeds through the pilot orifice and begins to build up downstream pressure. Figure 15b. Bleed Open, Excess Flow Valve Closed (Position B) Withdrawal Connection

23. Position C: As downstream pressure equalizes with tank pressure, the excess flow spring opens the main valve. The system is ready for transfer operations with the main valve acting as an excess flow valve. Releasing the operating lever to the closed position instantly closes both the main valve and the pilot valve (Position A). Figure 15c. Valve Open (Position C) Withdrawal Connection

24. Figure 16. Cable Installation Withdrawal Connection

25. Figure 17. Pump Pressure Operated Internal Valve (Flanged) Withdrawal Connection

26. Figure 18. Three-Way Valve Withdrawal Connection

27. Relief Valves Figure 19c. Open Figure 19b. Closed Figure 19a. Internal Relief Valve

28. Figure 20. Relief Valve Caps and Covers Relief Valves Relief valves are removed and independently tested as part of the cargo tank 5-year pressure test performed by a U.S. DOT Registered Inspector.

29. PTOs & Pumps Figure 22a. Tractor PTO Output Shaft Figure 22b. Connecting “Jack Shaft” Between Tractor and Trailer

30. PTO SHAFT HAZARD • WARNING: • DO NOT attempt to connect or adjust the PTO shaft section between the tractor and trailer with the engine running. • NEVER place any body part, clothing, hair, or hand-held object (within 3 feet of) a rotating PTO shaft. PTOs & Pumps

31. PTOs & Pumps Figure 23. In-Cab Pneumatic PTO Control

32. PTOs & Pumps Figure 24. Sliding Vane LP-Gas Pump

33. PTOs & Pumps Figure 24. Sliding Vane LP-Gas Pump

34. Never allow the pump to run dry. Liquid LP-gas is the lubrication and cooling material that protects the pump from premature wear and failure. PTOs & Pumps

35. Auxiliary Pump Inlet Figure 25. Auxiliary Pump Inlet

36. Liquid Meters Most transports are not equipped with a liquid meter. CTMVs in metered delivery service, however, have a liquid meter installed in the pump discharge line to account for the correct number of gallons delivered to customers. To ensure accurate inventory records, deliveries of propane to bulk plants and industrial customers are adjusted so the invoice displays the volume of gas at 60° F. Figure 26. State Weights & Measures Registration Decal on Meter Register

37. Transfer Hoses Vapor Equalizing Hose – Typically attached to the plant transfer bulkhead, but on CTMVs in metered delivery service, may be carried on the transport • Use of the vapor equalizing hose prevents or minimizes the following: • excessive pump cavitation • excessive pressure build up in the customer storage containers • venting of relief valves on customer storage containers in hot weather or on ASME tanks that fill to the liquid space

38. Transfer Hoses Delivery Hose Assembly (Liquid) – One of the most frequent causes of early failure of delivery hoses is damage from abrasion caused by vibrations of the hose. When this condition is detected, there are two important steps to be taken at once. The hose must be inspected more frequently and the cause of the vibration should be determined and corrected. If wear is so extensive as to expose the hose reinforcing fabric, the hose cannot be used until it is repaired and pressure tested or replaced with a new hose.

39. Emergency Discharge Control Systems • U.S. DOT regulations require the installation of either off-truck remote emergency discharge control systems or passive shutdown systems. • MC 330, MC 331, and non-specification cargo tank motor vehicles …. must be retrofitted with required emergency discharge control equipment at their first scheduled pressure test after July 1, 2001. All required retrofits must be complete by July 1, 2006. There are three types of emergency discharge control systems used on transports: • Manually actuated systems • Off-truck remotely actuated systems • Passive shutdown systems

40. Emergency Discharge Control Systems Manually Actuated Systems Figure 27b. Emergency Shutdown Station—Rear Deck Location Figure 27a. Emergency Shutdown Station—Front Trailer Location

41. Emergency Discharge Control Systems Off-Truck Remotely Actuated System Figure 28. Example of Off-Truck RF Device

42. Emergency Discharge Control Systems Passive Emergency Shutdown System – Passive emergency shutdown systems are systems that can stop the flow of product and stop the vehicle engine without human action within 20 seconds in the event of a complete delivery hose separation. Figure 29a. Passive Shutdown System Control Box Figure 29b. Discharge Line Sensor

43. Pull-away Prevention Devices Safety Air Brake Interlocks – The purpose of the interlocks is to prevent accidents such as moving the vehicle from a loading or unloading bulkhead with the PTO engaged or the hoses connected. Figure 30. Undercarriage Interlock Gate Open for Loading

44. Cargo Tank Labeling & Marking • U.S.Department of Transportation regulations require specific cargo tank markings, including: • Hazard Class Placards • Product Shipping Labels • Cargo Tank Inspection and Test Markings • Quench Tempered or Non-Quench Tempered Markings • Placards and shipping labels (Figures 31 and 32) are required on the front, back and both sides.

45. Cargo Tank Labeling & Marking Figure 31. Propane Shipping Label and Placard with LP-gas Identification Number

46. Cargo Tank Labeling & Marking *Some states may require decals stating, "WE STOP AT RAILROAD CROSSINGS," to be placed on the rear of the vehicle. Figure 32. Hazard Class Placards

47. Cargo Tank Labeling & Marking Tests & Inspections – The month and year of the latest required annual cargo tank inspections and the test and inspections required every five years must be shown near the cargo tank data plate. All commercial motor vehicles must also pass an annual vehicle inspection. Documentation of the annual mechanical inspection may be in the form of a decal. Cargo Tank Test and Inspections Annual Inspections5-Year Test and Inspection • Hydrostatic pressure test • (P test), and • Internal inspection • (I inspection) • External visual inspection • (V inspection), and • Leak inspection (K inspection).

48. Time to See If You Got the Key Points of This Module… • Complete the Review on page 29. • See if you are ready for the Certification Exam by checking off the performance criteria on page 30.