MODOT SPECIFICATIONS FOR:
SKID MOUNTED RIGHT-OF-WAY SPRAYER
It is the intent of this specification to describe a complete and operable skid mounted, chemical injection spraying system for the controlled application of herbicides. The spray system will be designed and constructed for convenient operation and simple installation on a flatbed or in a dump body.
Only new (unused) current standard production models built for the U.S. market will be considered acceptable. For equipment being offered to qualify as a standard production model, the manufacturer (vendor) must provide a list of three users that have operated their equipment for a minimum of three full spray seasons. Printed literature and specifications describing equipment as offered must be included with proposal. Any recent changes and features offered as standard or required for the intended use of the specified equipment will be supplied. All accessories required by these specifications shall be identical in quality and design to those normally supplied and installed for sale through regular commercial channels.
General Description: Shall be a spray system that includes but is not limited to a water tank, centrifugal spray pump, chemical tank(s), skid and saddle, spray head(s), handgun and computerized chemical injection control and pumping system. All plumbing and related components in the water and chemical systems must be non-corrosive type, compatible with chemicals currently used in the vegetation management programs.
1a. Water Tank: Shall be elliptical shape with 1000-gallon capacity (no exception). The tank shall have a removable, anti-surge “Butterfly Baffle” system (indentation in tank not acceptable) that reduces tank volume by no more than 1.5%. The tank and baffle material must be UV stabilized polyethylene. The tank will be saddle mounted and secured with a minimum of three (3) heavy duty, flat 11-gauge steel bands. A minimum of two bands must have “D” ring tie downs on both sides of the tank. The hose between the tank and sprayer pump shall be a 1 ½-in. non-collapsible suction hose. The suction line must include a glass filled, 1 1/2”-in. poly ball valve installed below the bottom of the tank. The ball valve will serve as the tank shutoff and drain valve. The tank lid shall be 16-in. diameter minimum, positive locking type with an air vent to prevent damage from pressure or vacuum.
1b. Fill System: Shall be a 4” air gap thru the center of the 16” tank lid. A 25 ft. 2” mill fire hose shall be supplied with unit with NPSH female fire hydrant swivel.
1c. Skid and Saddle Assembly: Shall be designed and constructed as an integral unit with 11-gauge formed steel. The design must maximize weight reduction and withstand the stress of frequent lifts on and off carrier vehicles. The saddle shall consist of three 12-in. wide flat steel sections formed to fit the contour of the water tank. The side jack supports between the saddle sections and skids shall be 1 ½-in. square steel tubing. The skid longitudinals shall be 137-in. long, hot rolled, sheet steel with break-formed flanges top and bottom (top flange to fit contour of the saddle sections). There shall be a minimum of five, 2-in. by 6-in. tube steel cross members between the longitudinals. The rear of the skid shall have 4-in. by 8-in. forklift pockets. The saddle and skid assembly shall be powder coat painted black.
2a. Sprayer Water Pump: Shall be a Hypro model 9303C-HM4 or approved equal with a 1 ½” inlet, 1 ¼” outlet, and direct-mount hydraulic motor. The pumping system shall maintain water pressure at a constant level as required for the intended use. The pump inlet, outlet and injection point fittings must be brass or stainless steel (no exceptions). A suction strainer with a 20- mesh stainless steel screen will be installed on the inlet side of the water pump. A high-pressure filter with a 40-mesh screen will be installed in the discharge line as close to the pump as practical (prior to the pressure reducing valves). The pumping system shall maintain water pressure at a constant level as required for the intended use. Mounting location for the water pump and related components must not limit access for normal maintenance.
2b. Sprayer Water Pump Drive: The skid unit will use existing closed center, load-sensing hydraulic system to power the sprayer pump at required flows and pressures when the chassis engine is operating at 800-1000 RPM. The hydraulic system utilizes a 5.48 or 6.0 cubic inch variable displacement, piston pump and is driven “live” from the front engine drive mounted to the crankshaft. The on-off switch for the sprayer pump will be located in the cab control center. The sprayer pump speed/pressure control will be a manually adjustable hydraulic flow control valve. The water pressure plumbing from the sprayer pump must include a 2 ½” liquid filled pressure gauge installed for easy viewing when adjusting the water pump speed control.
3a. Boomless Spray Head(s): The spray head (1) must produce a 30-ft. wide minimum, utilizing all brass, solid stream nozzles (plastic nozzles are not acceptable). The spray head shall have seven (7) adjustable, nozzle assemblies that produce individual spray swaths of 2ft., 2ft., 4ft., 4ft., 4ft., 6ft., and 6ft. The first four (4) nozzle assembly must nutate at 45 Hz to produce a uniform no streak spray pattern. The nozzles must be sized to apply 25-gallon per acre at 11 MPH. The spray head will have removable, steel side panels to minimize wind shear and protect components from roadside obstructions. The spray head stanchion (swing-post) will be a 2 ½-in. schedule-40 pipe. A heavy-duty receiver for the swing-post shall be located in the front of the skid. The sockets must have grease fittings and manually adjustable brakes that provide breakaway protection for the spray head. The spray head must swing a minimum of 180 degrees from the stowed to spray position. In the spraying position the face of the spray head will be approximately 24-in. outside the skid and tilt 30-degree up and down electrically from the cab control center.
3b. Spray Control Manifold: Shall be made of stainless steal and include a minimum of eight (8) TeeJet boom control ball valves, 3/4-in. adjustable pressure regulators and 2 ½” diameter liquid filled gauges facing the cab for viewing during operation and when adjusting pressure of nozzle assemblies. A water pump pressure gauge must be provided in a location that can be viewed when adjusting the engine/pump speed. The solenoid-regulator assembly will be stacked horizontally, across the rear of the skid. All spray head hose connections at the solenoid-regulator assembly must be 1/2-in. poly QD’s.
4a. Computer Console: Will be a Mid-Tech Tasc Model 6300. The computer will automatically maintain operator programmed output rates for each chemical injection pump within a maximum range of plus or minus 2%. The console will operate a minimum of three (3) chemical injection pumps. When spray width or vehicle speed changes, the computer will automatically adjust the chemical pump output (speed) within 5-tenths of a second. The computer will allow the operator to manually change rates on the go by maintaining primary and secondary application rates for each chemical injection pump. The console shall monitor spray width for a minimum of nine (9) spray swaths (boom-sections). Each section must be programmable in 1-inch increments from 0 to 99 feet. The console will receive ground speed and distance input from a skid mounted GPS unit.
1. During normal operation, the computer will display the following:
- Each open solenoid valve
- Width of each spray head/boom section
- Primary and secondary application rates for each chemical pump in (OPA)
- Total ounces of chemical dispensed by each injection pump
- Actual and simulated test speed of vehicle
- Distance sprayed in feet/miles
- Total area sprayed in acres
- GPM of carrier when stationary and gallons per acre when moving
- Automatically scan information available on LCD screen
2. When an uncontrolled condition occurs, the computer will display the following fault diagnostic information:
- Identify malfunctioning chemical pump
- Indicate chemical pump shutdown
- Indicate pump running out of programmed operating range
4b. Chemical Injection Pumping System: Will utilize computer controlled, DC powered, peristaltic pumps (no exceptions). The pumps will inject chemical at the water pump inlet. The pump drive motor and the controller will be totally covered with a rugged weather tight enclosure that can be easily removed. The two (2) pumps will be Teejet Legacy pumps sized with output rates from 1 to 350-ounces per minute.
4c. Chemical Concentrate Tank(s): Will be UV stabilized polyethylene with molded gallonage markers. One 3/4-in. brass ball valve shall be installed in the bottom of each tank. This ball valve shall act as tank shut off valve and tank drain. A second (2) ¾” nylon ball valve shall be installed as close to the tank and injection pump for calibration. There shall be two (2) 30-gallon cone tanks. The tanks will be mounted in stands on heavy-duty base plates and secured with a 1/8-in. by 4-in. adjustable steel band around the top, vertical portion of each tank. All chemical tanks shall include low level sensors with indicator lights in the cab control center.
4d. Chemical Tank Agitators: The 12-Volt DC drive motors must have Viton lip seals for corrosion protection. Each agitator shall have a propeller on a stainless-steel shaft. The agitator on-off and hi-low speed controls shall be in the cab control center. Both 30-gallon cone bottom tanks will have agitators.
5. Remote Cab Control Center: Must have a computer console and separate electro-mechanical console. All sprayer controls must be in the two consoles (no exception). Both consoles will be installed in a steel framework designed to attach to a floor-mounted pedestal or loose on the seat. The control system must include all necessary cables for use on intended vehicle. A heavy-duty insulated battery cable receptacle will be provided at the front of the skid. A power cable of adequate length will also be provided to connect skid with chassis battery.
6. Mechanical Control Console: To be a console that includes switches for spray head tilt and fold, beacon light, water pump on/off, engine start/stop, on-off for nine (9) spray head solenoids, two (2) chemical tank level indicators and two (2) chemical tank agitators. The agitator switches must have high and low speed. All switches will have indicator lights and labels identifying function and action for each. The console shall also include controls for overriding ground speed input and selecting sprayhead or handgun mode.
7. Handgun Hose Reel: Shall include an electric hose reel, 100 ft. of ½-in. x 600 PSI chemical resistant hose and a Model 43L hand gun. A flow switch will be installed at the hose reel to turn chemical injection pumps off when handgun trigger is released. A ½-in. brass ball valve must also be installed at the hose reel to shut off handgun supply.
8. Plumbing: Any excessive pressure drop or back pressure due to restrictions from under sized components will not be acceptable in the chemical or water pumping systems. All hosed and fittings will be rated to exceed by 50 percent any maximum operating pressures possible in their respective systems. Any hoses installed in locations where chaffing or other damage may occur must have protective coverings. All hoses will be adequately supported throughout the system. A 1 ¼-in. outlet with ball valve will be installed in the stainless-steel manifold to attach hose for fire fighting.
9. Hand Wash Tank: An approved nine (9) gallon tank shall be furnished with the unit.
10. Warranty: A minimum of one-year parts and service will be furnished. Any components with a longer manufacturer warranty will be listed. In addition, the vendor must provide a loaner injection sprayer control (computer), injection pump, or control console within 24 hours from the time user agency and manufacture (vendor) determine repairs cannot be made in the field. Each unit shall include all inspection coupons, certicqards, or warranty identification cards normally furnished to the trade in general accordance with standard warranty policies. Vendor must operate full time parts and service facility offering factory authorized service.
11. Manuals: One detailed set of parts, service and operator manuals will be delivered with the sprayer. A plumbing schematic detailing sprayer components and their location will be supplied at the time of installation and training.
12. Training: Vendor will furnish a minimum of 8 hours training on operation and maintenance of the unit at a time and location mutually agreed upon by the vendor and purchaser.
OPTIONS:
1. Gas Powered Sprayer Pump: Shall be a Hypro model 9203C heavy duty centrifugal, capable of 90 PSI and 60 GPM. The injection point fittings at the water pump must be brass (no exceptions). The pump will be belt driven from an engine with a direct mount, heavy duty, 12-volt DC, electromagnetic clutch. Clutch power will be through an on/off switch at the cab control center. The pump mounting base must be slotted to allow the removal or adjustment of drive belt. A 40-mesh filter with a replaceable stainless steel screen will be installed in the pump pressure line. The pumping system must provide a minimum 75 PSI water pressure to the pressure regulators when operating nozzle assemblies either individually or simultaneously. The water pump power will be a minimum of a 14 hp engine with remote electric start/stop. A group 24 Battery must be supplied and installed. The mounting location for the pumping system and battery must not limit access for normal maintenance.