Truss is 43" deep and is constructed of ASTM A-36 structural angles, which are jig welded to AWS specifications. Chords are 3" x 3" x 1/4" angles with 2" x 2" x 3/16" web members. Head, tail and gravity take-up sections are factory assembled. Intermediate Sections are available with chord punching for 3' - 6"  or 4' - 0" carrier idler spacing. They are also available with field-bolted wind bracing (to minimize shipping costs), or factory welded wind bracing (to minimize field assembly). Internal K-braces maintain box-truss "squareness." Standard section lengths combine for total conveyor lengths at 6" increments (90' - 0", 90' - 6", 91' - 0", etc.). Internal frame clearance is 12" wider than belt (compared to many other frames which are 8" and less). Standard belt widths are 18", 24", 30", 36", 42" & 48". See Table A.

TRUSS JOINTS

Two bolts are provided at each chord, thereby allowing use of "drift pins" for ease of assembly and erection.

PULLEYS

Heavy duty, all steel welded type, individually turned and crowned to ensure true concentricity with the bore. Faces of the pulleys are machined Pulleys are equipped with Taper-Lock and QD hubs and bushings.  OSHA/MSHA Pulley Guards and Tail Pulley Cage are standard.

IDLERS

MARCO Series M15 - 4 1/2" dia rolls, with pre-lubricated ball bearings which require no further lubrication. Troughing idlers are spaced on 4' - 0" centers with two extra at the loading point; return idlers are spaced on 10' - 0" centers. 35^o idlers are standard. Idlers of other types and spacing are available upon request, at prices which vary with specifications.

BELT TAKE-UP

Screw type acid cleaned and plated, providing 21" adjustment (furnished when gravity take-up is provided). Gravity type take-up is optional at additional cost.

GRAVITY TAKE-UP

Optional but recommended in many cases. Vertical gravity take-up assemblies include two bend pulley assemblies and a sliding (take-up) pulley assembly with cage and slide rails. Take-up weight is not included. A shedding deck, equipped with gum rubber flashing, is mounted over sliding pulley to prevent entrance of material between belt and pulley.

RETURN BELT WIPER

"Plow type" belt wiper, rubber flashed, mounts in front of tail pulley to prevent entrance of material between return belt and pulley. Wiper assembly moves with tail pulley when a screw take-up is provided. Wiper is standard with solid drum tail pulleys, optional with self-cleaning tail pulleys.

ASSEMBLY BOLTS

High strength bolts are required. A325, or Grade 5, bolts are provided as necessary.

LOADING HOPPER

The loading hopper is 5 ft. long, 8" in depth and is designed to appropriately center material on the belt. It is equipped with adjustable gum rubber flashing to prevent leakage. Hopper length can be extended to any dimension, resulting in continuous side skirts.

SUPPORT LUGS

Heavy steel  lugs provide a pin-jointed connection to either steel or timber   supports. Quantities of lugs are provided in accordance with recommended spans shown in "Table B".

CONVEYOR SPAN

Spanability varies with load conditions, weight of material, belt width, accessories. etc. See "Table B" for allowable spans.

MOTOR SUPPORT

Structural steel mount positions motor well above material burden. Furnished for right-hand drive (facing in direction of belt movement), unless otherwise specified.

CONVEYOR DRIVES

Drive includes shaft mounted helical gear speed reducer (gears are enclosed and running in oil)  driver and driven sheaves and vee belts. All drive components are selected to adequately transmit horsepower required for Class I Drive (1.0 Service Factor). Class II optional (1.4 Service Factor). OSMA/MSHA drive guard with "back" is standard.

When conditions indicate the belt and load will reverse under power failure, a backstop is provided. Backstop is mounted in the shaft mounted reducer, and runs in oil.

ELECTRIC MOTORS

Horsepowers vary with capacity length and incline. Motor sizes are selected with ample safety factors to provide an efficient and reliable power source. 1800 RPM, TEFC, Nema design "C", hi-torque, 3 phase, 60 cycle, 230-460 volt motors are considered standard. Other enclosures, and motors with other electrical characteristics, are also available.

CONVEYOR BELT

The use of 35^o troughing idlers on 4 ft. centers provides ideal conditions for the use of belts with synthetic fabrics. Strength of fabric, number of plies, and thickness of rubber top and bottom covers are combined to ideally satisfy the installation requirements.

OPTIONAL SPECIFICATIONS

OSHA WALKWAY BEAMS (SUPPORTS) WITH TOE PLATE

(See Walkway Specifications)

Walkway beams are structural channels   spaced on 4' - 0" centers or 3' - 6"  while handrail supports are on 8' - 0," or 7' - 0' centers respectively. Two strands of 1.66" O.D. galvanized tubular hand-railing with attachment hardware, designed for "continuous grip".   Walkway and handrail conform to MARCO interpretation of OSHA/MSHA specifications, i.e., "...handrail shall be able to accept a 200 lb. force in any direction...". Walkway beams are available for one, or both, sides of the conveyor.

WALKWAY DECKING

Decking is 24" wide galvanized "Grip-Strut" with integral 4" high toe plate,  inboard and outboard. Decking widens to 36" at the conveyor drive.

HINGED CONVEYOR HOUSING (Carrier Belt)

Conveyor housing is of galvanized steel construction, "curved-formed" for maximum "weather shedding" and intermittently corrugated for weather tightness and rigidity. Support bands are centered between idlers, giving free access to moving parts when housing section is opened. Mounting hardware provides for vertical height adjustment.

RETURN BELT COVER

Formed 16 ga. sheet metal deck to divert carrier belt spillage away from return belt. Furnished with plated assembly bolts. 'While return belt covers are available as an option. they are generally not recommended for most installations.

BELT WIPER ( For Head Pulley )

Equipped with double rubber squeegee and adjustable tension spring, providing constant pressure on belt surface. Mounted under pulley to provide greatest efficiency.

RUBBER LAGGING ( Heavy Duty ) FOR CONVEYOR PULLEYS

Heavy duty, top quality "ruff-top" rubber lagging - can be furnished on either crown or flat face pulleys. Installed in multiples of 6", 8" and 10" widths to ensure conformity to crown face. Recommended on drive pulleys where there is a possibility of belt slippage. Slide lagging and vulcanized lagging optional.

CONVEYOR SUPPORTS

A-frame supports and support towers are available to satisfy most requirements. Structural A-frame supports are available through 92' in 6" increments.

OTHER OPTIONS

• Shuttle Conveyors
• Wind Guards (Retainers)
• Transition Sections
• Discharge Hoods
• Transfer Chutes
• Self-Cleaning (Wing Type) Pulleys
• Aluminum Drip Troughs
• Continuous Side Skirts
• Class II Drives
• Emergency Stop Cord