Patent Description:
Underground or buried vaults, pits, chambers or boxes used in the utilities, security and rail line sectors or other industries can contain co-axial or optical fiber, copper cable as well as gas and power lines and other conduits, industrial valves, Wi-Fi antennas etc. Vaults and pits for underground utilities often need to be opened for making repairs or for enhancing services. Typically utility vaults and pits include a concrete, polymer concrete, cast iron, galvanized steel or plastic lid which is opened by a tool or pick with a hook at one end. The hook is inserted through a hole in the lid or cover and is used for prying the lid or cover away from its opening atop the vault or pit.

Because underground utility vaults or pits are often times required to be located in sidewalks, right aways, alley ways and streets or other high traffic areas, the cover must be constructed to withstand substantial loads. Consequently current lid or cover construction is made from concrete, polymer concrete and cast iron in order to withstand the required loads. These cover materials can withstand substantial loads and have a degree of durability required for use in various traffic areas. A drawback of these cover types is AD:IG:WI:ko that they are quite heavy, weighing in excess of <NUM> pounds or more depending upon the particular application. Consequently, due to their weight, they are difficult to remove for repair, maintenance or adding additional services within the apparatus contained within the utility vault or pit. Heavy covers can cause injury or other back problems to workers during removal and reinstallation of the covers.

Utility vault and pit covers are also made of plastic but these have limited application for use in areas where they are subjected to less load, i.e. green belt or yard applications. The problem with plastic lids is that because they cannot withstand substantial loads, they have limited applicability and plastic lids provide less coefficient of friction when wet versus polymer covers. Consequently a need exists for a new utility vault and pit cover design which is light in weight, yet is durable in that it can withstand substantial loads and provide improved slip resistance over currently available covers.

<CIT> discloses a burial vault made of a polymeric material. The burial vault includes a generally rectangular lower box portion and a generally rectangular upper lid portion. Each of the lid and box portions of the vault include substantially parallel lateral ribs integrally formed therein which are in alignment with and cooperate with one another. In addition, each of the lid and box portions include weight transferring and weight bearing ledges. Fastening and sealing mechanisms are also disclosed.

<CIT> discloses a molding apparatus and a method of molding for components of unvulcanized elastomeric material which forms a spew free component and provides for handling the component for subsequent use. The apparatus comprises a first mold member having a mold cavity for part of the component and a feed port for material and a second complementary mold member which includes a detachable component carrying insert. The two mold members and are relatively movable to provide two different volumes for the mold cavity, the change to the smaller volume being used to return some material through the feed port and to complete molding of the component.

<CIT> discloses compositions and methods of manufacturing articles, particularly containers and packaging materials, having a particle packed, inorganically filled, cellular matrix. Such an article may for example be containers and lids. Components can be added to a material mixture to vary the properties of the final product. Such components include fibers. The disclosed method includes, once the moldable mixture has been prepared, positioning the mixture within a heated mold cavity. The heated mold cavity may include molds typically used in conventional injection molding processes and die-press molds (a male and a female mold) brought together after placing the inorganically filled mixture into a female mold. Surface texture may be controlled by varying the temperature between molds.

<CIT> discloses a polymer matrix composite inspection shaft cover mold tool comprising a matrix, a counter die having a cooling water cavity in an upper and lower mold and provided with an ejecting mechanism.

<CIT> discloses a process for manufacturing a manhole cover for pits comprising mixing of fibers of suitable reinforcement material. This manhole cover comprises an upper face and a lower face which may be provided with reliefs or channeling.

<CIT> discloses a manhole cover made of a reaction injection molded product having a texture pattern on its surface and a method for manufacturing the manhole cover. The mold device provided with a first mold halve and a second mold halve for forming a reaction injection molded manhole cover. The mold also comprises a wrinkling pattern.

<CIT> discloses a mold for molding a fiber reinforced polymer material lid.

The present invention relates to a mold for molding a fiber reinforced polymer material utility vault lid comprising:.

The present disclosure provides an improved utility vault cover or lid which is manufactured from a fiberglass reinforced polymer matrix material producing a reduced weight and increased strength cover which is lighter, stronger, has improved UV characteristics and slip resistance and is less expensive to manufacture compared to existing cover designs. The lid or cover is used for vaults, pits, chambers or boxes and for ease of presentation shall all be referred to herein as a vault. Vaults are used in a number of industries including utility, security, gas and rail, for example, where they are underground, buried or at grade level.

The fiberglass reinforced polymer matrix (FRPM) material is a fiber reinforced polymer material which consists of an unsaturated polyester thermosetting resin matrix, glass fiber reinforcement and inorganic or mineral filler. Additional ingredients are low-profile additives including a UV inhibitor, cure initiators, thickeners, process additives and mold release agents. The formulation undergoes a cross linking reaction when cured under heat and pressure. The fiber reinforced polymer material for the cover will retain its original material properties and dimensional accuracy over a broad range of temperatures. The cover is on average fifty percent lighter than concrete and polymer concrete covers and sixty-five percent lighter than cast iron lids.

The fiber reinforced polymer material is made as a continuous sheet wherein a resin paste is transferred to a doctor box where it is deposited onto a moving carrier film passing directly beneath. Glass fiber rovings are fed into a rotary cutter above the resin covered carrier film. Chopped fibers are randomly deposited onto the resin paste. A second carrier film is coated with resin paste and is laid resin side down on top of the chopped fibers. The layers are then sent through a series of compaction rollers where the glass fibers are consolidated with the resin paste and the air is removed from the sheet. The fiber reinforced polymer material sheet is kept in a temperature room until the desired molding viscosity is reached.

When the polymer material is ready for molding it is cut into pieces of a predetermined size. The cut pieces are then stacked and assembled into a charge pattern that is the optimum shape and volume to fill a mold cavity. The mold is then closed and the polymer material is compressed. The mold is held closed for a predetermined amount of time to allow the cover to cure. After curing, the mold is opened and the cover is ejected from the lower mold surface with the use of integral ejector pins. The cover is allowed to cool to room temperature before any necessary machining operations. The manufacturing process can be automated through the use of robotics.

The manufacturing process includes low pressure molding in combination with a mold design which incorporates a steam pot to heat the mold, results in lower mold cost, lower material cost and faster cycle times. The mold design allows for low pressure molding which provides faster cycle times resulting in lower production costs while producing a reduced weight and improved performance lid.

The cover consists of an uppermost surface which is flat and in its installed condition on the vault is even with grade. The bottom side of the cover or lid has an outer rim with a recessed interior area or cavity. The cavity includes features to allow for the attachment of accessories and thru-holes as required. The bottom of the lid has continuous support ribs spaced in the cavity to transfer load and minimize deflection under load to the outer rim. The outer rim is supported by the vault, frame or other type of supporting recess. In an embodiment, the ribs are uninterrupted for the span of the cavity to the rim to provide strength to the lid.

The uppermost surface of the cover lid has a texture or a surface condition created by a pattern of features at different depths. The change of depth of the flat surfaces creates a protrusion into the surface to push the glass component of the material away from the surface creating a resin rich surface. The top surface also has a series of bosses having shapes of varying heights to allow for aggressive transitions in the surface of the lid. These shapes are arranged in a pattern to allow for additional edge surfaces to grip moving surfaces which may come in contact with the top of the cover. The combination of the UV inhibitor, boss design and surface texturing creates improved UV characteristics and prevents glass fiber blooming. The elevation of the bosses, spacing and angles, along with the texturing of the surface enhances the coefficient of friction of the gripping surface resulting in improved slip resistance.

The cover or lid is designed to allow for installation of either an "L-bolt" or a "thru-bolt" for securing the lid to the vault. Self-latching locking assemblies can also be incorporated. The lid also incorporates features to allow for the installation of a pick hole retaining cup for use in removing the lid from the vault.

These and other features of the present invention will be more fully understood by reference to the following detailed description and the accompanying drawings.

Referring to <FIG>, an embodiment of the invention is a fiber reinforced polymer material utility vault or pit cover or lid <NUM> consisting of an unsaturated polyester thermosetting resin matrix, glass fiber reinforcement and inorganic or mineral filler. It is to be understood that the invention is a lid or cover, and these terms are used interchangeably throughout, for a utility vault or pit which are also interchangeable terms used throughout the specification. The matrix further includes a low-profile additive, a cure initiator, a thickener, a process additive and a mold release agent. The additives include a UV inhibitor. The additional components are used to enhance the processability of the material and the performance of the lid. Less than about <NUM>% of the fiberglass reinforced polymer matrix formulation is a petroleum based product comprising unsaturated polyester resin and thermoplastic additives, the remainder is inorganic or mineral filler and reinforcing glass fibers chopped into, for example, one inch lengths. The mineral filler could include, for example, alumina trihydrate, calcium carbonate, talc or clay. The polymer material undergoes a cross linking reaction when cured under heat and pressure. Good heat resistance is a characteristic of all thermoset materials and they differ from thermoplastic material in that once the compound cures into a rigid solid it will not soften at elevated temperatures or become brittle at lower temperatures. The lid retains its original material properties and dimensional accuracy over a broad range of temperatures. UV resistance is optimized through a combination of using orthophthalic resin, polystyrene as the low profile additive for shrink control and alumina trihydrate filler to produce the best results against weathering. A low level of organic material coupled with the use of inorganic fillers, for example alumina trihydrate, results in the material being highly flame retardant. Using the UL Bulletin <NUM> protocol as a measure, the material performs at the highest possible 5V flammability classification.

Referring to <FIG>, the fiberglass reinforced polymer matrix is manufactured as a continuous sheet <NUM>. Mixed resin paste <NUM> is transferred to a doctor box <NUM> wherein it is deposited onto a moving carrier film <NUM> passing directly beneath the doctor box. The doctor box controls the amount of resin paste that is applied to the carrier film. Glass fiber rovings <NUM> are fed into a rotary cutter <NUM> above the resin covered carrier film. Chopped fiberglass fibers <NUM> are randomly deposited onto the resin paste. The amount of chopped fiberglass that is deposited is controlled by the cutter and the speed of the carrier film. Downstream of the chopping operation, a second carrier film <NUM> is also coated with resin paste <NUM> by a second doctor box <NUM> and is laid resin side down on top of the chopped fibers <NUM>. This process creates a resin paste and glass fiber sandwich which is then sent through a series of compaction rollers <NUM> wherein the glass fibers are wet out with the resin paste and the air is squeezed out of the sheet <NUM> to produce a homogenous sheet of fiberglass and resin.

Before the fiberglass reinforced polymer matrix sheet can be used for molding it must mature. This maturing time is necessary to allow the relatively low viscosity resin to chemically thicken. The sheet is kept in a temperature room until the desired molding viscosity is reached. When the sheet is ready for molding it is cut into pieces of a predetermined size. As shown in <FIG> the cut pieces are then stacked and assembled into a charge pattern <NUM> that is the optimum shape and volume to fill a mold cavity in a mold <NUM>. The charge pattern is then weighed for verification of correct charge weight. The preassembled charge is then placed on heated mold surfaces <NUM> in a predetermined location. The mold <NUM> is a matched set of machine steel dies comprising a cavity die <NUM> and a core die <NUM>. The mold cavity is positioned between the cavity die and the core die.

The mold is heated, for example, by steam. After the charge is placed in the mold cavity, the mold is closed and the charge is compressed. The fiber reinforced polymer matrix material is a flowable compound and under heat and pressure is transformed from a thick paste to a very low and optimized viscosity liquid of viscoelastic state. The material flows to fill the mold cavity. As seen in <FIG>, the cavity die <NUM> and the core die <NUM> are interfaced by a telescoping shear edge <NUM> which provides for a gap between the core die and the cavity die to allow for the core die to enter the cavity die. The telescoping shear edge allows for the material to be controlled during the molding or compression phase of the process. The clearance at the shear edge allows the escape of air ahead of the material flow front. The small clearance of the shear edge allows air to pass but it is too small to allow an appreciable amount of the polymer material to pass. The mold is held closed for a predetermined amount of time to allow the cover to cure. After curing, the mold is opened and the cover is ejected from the mold surface of the core with the use of integral ejector pins. The hot molded lid is placed into a cooling rack and allowed to cool to room temperature before a machining operation.

Referring again to <FIG> the mold <NUM> includes an ejector system <NUM> for ejecting the finished molded part. The mold can be made from A-<NUM> tool steel for example, however other materials could also be used. The core die and cavity die are aligned by components in the tool, for instance alignment pins and bushings. Stop pads are utilized to control part thickness. As shown in <FIG>, the core die and cavity die are provided with a means to control the temperature of the blocks. For example a steam pot <NUM> can be incorporated. The temperature of the mold is monitored by means of a thermocouple <NUM>. The steam pot is a sealed cavity <NUM> which has internal supports <NUM> surrounded by an outer perimeter <NUM> and sealed with an additional plate <NUM> to maintain pressure and control the steam. A steam pot is utilized in both the core die and the cavity die and allows steam to be used to provide a consistent and uniform heat transfer to the mold surfaces <NUM>. The surface area of the steam pot cavity allows for increased surface area for transfer as opposed to drilled lines. Other means to control the temperature of the blocks can include drilled holes or slots used with oil or electrical heating elements.

Referring to <FIG> the ejector system <NUM> includes ejector pins <NUM> utilized to push the molded part off of the core die <NUM> at the end of the molding process. The ejector system includes an ejector plate <NUM> which pushes a group of ejector pins that are flush with the top of the core die or the bottom of the part lifted from the core die. The ejector pins <NUM> are retained on the ejector plate <NUM> by means of a retainer plate <NUM> which has counter bored holes to capture the head of the ejector pins. The ejector plate assembly is guided by means of guide pins <NUM> and bushings <NUM>. The ejector plate is actuated by hydraulic cylinders <NUM> (<FIG>) controlled by the molding cycle. Actuation of the ejector plate can be achieved by other means such as chain poles or knockout bars in the apparatus. The ejector plate assembly is supported by rails <NUM>, support pillars <NUM> and a bottom plate <NUM>. The ejector plate also has a provision for heating the mold with drilled holes for steam.

The top, bottom and sides of the mold assembly can be insulated to contain the heat required for the process. It also insulates the heat from the machine or hydraulic press to manufacture the part.

The polymer formulation is typed into an automated delivery system. This system is responsible for mixing of all of the ingredients together, storing the polymer matrix and then delivering it to a compounder, for example a Schmidt and Heinzmann (S&H) Compounder.

The formulation is mixed to ensure that the material is homogeneous. Controllers manipulate the order of addition, dwell time, blade speed and mixing temperature. Upon completion of paste matrix mixing cycle, several tests are performed to make certain the paste is correct before being released to a holding tank. The holding tank's primary function is storage. During the storing process, the paste matrix is agitated by low shear mixing blades. If the weather is less than <NUM> F degrees (<NUM>,<NUM>) a water blanket is used to make sure that the paste does not lose temperature. This loss can influence the thickening response and negatively impact the moldability of the material. The holding tank is placed on a scale and is continuously metered gravimetrically to the compounder during manufacturing. The polymer matrix still does not have color or the thickener (polymer extender). Both of these ingredients are added separately to ensure that there is not any cross contamination in color or troublesome thickening because of improper maintenance. The "b-stage" component is tested to confirm the desired formulation before it is released into production.

Batch mixing is typically used when formulation flexibility is required. When the lids are manufactured with one formulation, a continuous process can be employed. This allows the mixing process to be tailored to one specific formulation. All of the ingredients are continuously fed to a mixer, typically an extruder. They are blended together in the extruder and introduced into the compounder. This process eliminates the additional equipment needed to feed and mix the b-side.

The automated delivery system will determine pump rates needed for manufacturing. This system will determine the amount of paste delivered per hour to the compounder based on the matrix specific gravity, product weight, glass percent and sheet weight. The matrix and b-side are combined by running through a series of high shear cowls type mixing blades or a static mixer. The mixed material is then stored in a surge tank and delivered to the compounder with stater pumps. Inside of the doctor blades on the compounder are height sensors. The height of the material in the doctor boxes is controlled by the automated delivery system.

There are many variable that can be changed on the compounding machine such as:.

Since the specific gravity of the material is known, the height of the doctor blades can be determined based on the product weight of the material. The product weight of the compound is measured by the weight per unit area. Typically weight is measured in grams/ft<NUM>. The fiberglass component can also be measured. Varying the RPMs of the chopper will linearly change with the weight of the fiberglass. The product weight of compound is <NUM>/ft<NUM> (<NUM>/m<NUM>).

Paste samples (matrix and b-side together) are taken throughout the run and measured with a viscosmeter. Typical measurements are taken initially, at <NUM> hours and at <NUM> - <NUM> hours. Several variables are considered when determining the thickening curve: temperature, initial viscosity and molding viscosity. These values are optimized based off of prior compounding and material trials. When lot number of either the resin or the thickener change, a thickening study is run to determine if the levels need to be changed. The target molding viscosity of the material is between <NUM>-<NUM> cps (<NUM> Pa·s). Viscosity measurements are taken with a Brookfield DV-II.

After the polymer matrix is introduced to the fiberglass the sheet is then squeezed together between serpentine rollers to wet-out the fiberglass. Since this process yields structural parts, a ft<NUM> template is used to cut a sample of the material. If it falls within a predetermined range, the material is qualified for release.

The product weight samples are collected and used to mold lab panels. During the molding a sensor detects the dielectric properties of the material and determines the gel and cure time of the material. The cured panels are then cut up into various samples for testing. Typical testing includes tensile strength, flexural strength, specific gravity, fiberglass content and water absorption.

Once the material has reached the predetermined values of the quality testing, the material is released into production.

• The press is preheated to ensure the proper settings. • A notebook of Master Control Settings is consulted for the sheet for the particular lid to be molded and screens <NUM> and <NUM> are set to the proper Control Settings. This Master Control Settings Record Sheet shows proper setting for each of the following:.

• The operator reviews the temperature indicators on the master Control panel to see if the molds are up to the proper temperatures, <NUM>° F-<NUM>° F (<NUM> - <NUM>) for upper tools and <NUM>° F-<NUM>° F (<NUM> - <NUM>) for lower tools. • Once the screens are checked the operator take a hand held temperature gauge and verifies that the mold temperatures match the screen readings from the thermocouples. He is also verifying that the upper mold is always hotter than the lower mold to avert any telescoping shear edge mold crash. • Once the temperatures are verified the operator then visually inspects the mold surfaces for cleanliness and any sign of debris or scumming. If any is seen it is removed with brass tools and air streams. • The press is then set into Automatic mode and readied for the molding of the first part.

• The delivered charges are inspected and measured to ensure they are the correct size and weight. The first charge is staged on the scale and the weight is noted. On the PROCESS DATA &PARAMETERS MASTER CONTROL SETTINGS RECORD SHEET there is a heading "CHARGE DIMENSIONS". Under this headings are the following line items that contain the proper information regarding the charge for example, a <NUM> x <NUM> (<NUM>) charge:.

• Once the charge has been confirmed to meet specification, the green "CYCLE START" button is pushed to activate the automatic molding cycle and the mold lowers to LOAD POSITION. • Once the mold stops to the load position, the charge is delivered into the mold via a loading device and the charge is precisely position on the lower mold being centered in each direction. • As soon as the loading tool has exited the mold parameters, the operator again pushes the green "CYCLE START" button and the press lowers from "SLOW DOWN POSITION" to "CLOSED POSITION". Once the presses sensors confirm that each corner is at Full Closed position, the "CURE TIME" cycle starts. • As the automated cycle starts the operator inspects and places the next charge onto the scale again verifying the weight. • After the CURE TIME cycle is completed, the air poppet is automatically activated and the press opens to SLOW SPEED position and then opens to FAST SPEED and returns to the OPEN POSITION setting of the cycle. • As the press is opening to OPEN POSITION and the mold has cleared the full extension dimension of the ejector pins and reaches a preset clearance height, the ejector system is activated and the part is raised above the lower mold surface to the full height of the ejection pins. • As soon as the ejectors have reached full height, the Unload Tool is inserted under the part and the ejector rods are automatically lowered. • Once the ejectors are back in full rest position, the Unload Tools is extended to the front of the press and the part is delivered to the operator to do a visual inspection, deflash the edges and place in the cooling cart. • Once the part and the Unloading Tool have been removed from the press parameters, the operator visually inspects the mold surfaces and clears and debris with an air stream. The cycle begins all over repeating each of the documented steps.

Referring again <FIG>, the lid or cover <NUM> includes an uppermost surface <NUM> which is substantially flat and when installed on a vault or pit <NUM> is even with grade level surface. As shown in <FIG>, the bottom side <NUM> has an outer rim <NUM> around the perimeter of the lid with a recessed interior area or cavity <NUM>. The cavity has features <NUM> and <NUM> to allow for the attachment of accessories to be discussed in more detail subsequently herein and thru-holes <NUM> for attachment to the vault <NUM>. A plurality of continuous support ribs <NUM> extend from opposite sides of the outer rim within the cavity. The support ribs are spaced to transfer load and minimize deflection of the lid under load to the outer rim. As shown in <FIG> the outer rim is supported by a ledge <NUM> in the outer walls <NUM> of the vault <NUM>. Although the lid is shown as being supported by a ledge <NUM> in the walls of the vault, other types of supporting recesses of the vault are contemplated to support the lid.

The ribs <NUM>, for example three, extend uninterrupted laterally to span the cavity between opposite sides of the perimeter of the rim. As shown in <FIG> alternative designs were tested to determine the effect of additional supporting structures within the cavity <NUM> of the lid <NUM>. The ribs <NUM> (as shown in <FIG>) were superior to alternative designs which incorporates intersecting ribs <NUM> extending the length or portions of the cavity. The lid of <FIG> also incorporated intersecting hubs <NUM> and it was shown through testing that ribs <NUM> alone improve the load carrying capability and therefore intersecting ribs <NUM> and hubs <NUM> are unnecessary. The test results as shown in Table <NUM> illustrate the lid design as shown in <FIG> comprising a polymer material as disclosed herein produced a larger load carrying capability when the intersecting ribs <NUM>, hubs <NUM> and small ribs <NUM> were removed.

In addition deeper ribs <NUM> as shown in <FIG> produced the largest load carrying capability. Ribs <NUM> also can have a curved outer radius <NUM> allowing the rib to have a height in the center taller than at the juncture with the outer rim.

As shown in <FIG> and <FIG>, the top surface <NUM> includes a textured surface <NUM> or surface condition created by a pattern of features at different depths in the mold surface. The textured surface <NUM> includes a change of depth of the flat surface which creates a protrusion <NUM> into the surface to push the glass fibers <NUM> of the material away from the surface creating a resin rich surface <NUM> during molding. Having the glass fibers <NUM> away from the textured surface adds to the long term weatherability of the lid. The textured surface is, for example, a Corinthian texture. The combination of the texture and the UV stability achieves a delta E values of less than <NUM> when exposed for <NUM> hours using the SAE J2527 test.

The top surface <NUM> also includes a series of bosses <NUM> of varying heights to create a gripping surface. The bosses <NUM> are molded at various heights to allow for aggressive transitions in the surface of the lid. The bosses are arranged in a pattern of alternating groups which allows for additional edge surfaces to grip moving surfaces, such as vehicle tires, which may come in contact with the top of the lid. The bosses create more surface area for flexible materials to come in contact with. The result of the bosses is the surface allows the lid to meet slip resistance requirements. Although <FIG> illustrates a boss pattern of alternating series of three bars having rounded ends, it is to be understood that other geometrical shapes and sizes and arrangements are possible to create the necessary tread pattern or slip resistance surfaces. Other testing requirements the lid of the present invention meets are as follows:.

The lid is tested to industry recognized standards for:.

As shown in <FIG> the top surface <NUM> has a recess <NUM> for the attachment of an identifying component <NUM> such as an ownership marker as shown in <FIG>. The ownership marker would have a post extending into hole <NUM>. The identifying marker could be removed and exchanged in case of change of ownership of the lid.

Referring again to <FIG> the lid includes holes <NUM> and <NUM> extending through the lid to allow for either bolt down or captive locking options to attach the lid to the vault. As shown in <FIG> either an L-bolt <NUM>, or alternatively a thru-bolt <NUM> passes through either hole <NUM> or <NUM> and would be rotated to engage a groove <NUM> positioned in the wall <NUM> of the vault as shown in <FIG>. The L-bolt <NUM> is retained within a housing <NUM> attached to fastening feature <NUM> positioned on the bottom side of the lid. As shown in <FIG>, a flange <NUM> would be attached to fastening surfaces <NUM> which would engage a groove <NUM> in the wall <NUM> of the vault.

Any unused holes <NUM>, <NUM> not utilized for a particular attachment system can be closed with a removable plug <NUM> (<FIG>) which at any time could be removed for the incorporation of a different securing option.

As shown in <FIG> the lid includes a pick hole <NUM> for lifting the lid off of the vault. As shown in <FIG> a pick hole retaining cup <NUM> (also shown in <FIG>) is positioned within the pick hole <NUM> which has a rod <NUM> positioned in a recess across the opening which can be engaged by a hook to lift the lid off of the vault. As shown in <FIG> the lid includes a pick hole cap <NUM> to prevent debris from collecting within the pick hole during use.

As shown in <FIG>, the molding and machining operations can be automated through the use of robotics <NUM>. A robot <NUM> having a programmable logic controller would move from a neutral position to a charge loading station <NUM> where an operator would load a charge pattern <NUM> onto a loader <NUM> positioned on an end of an arm <NUM> of the robot. The programmable logic controller of the robot then moves the loader to the neutral position facing the mold press <NUM>. The robot waits in the neutral position until the mold press opens and the controller makes sure the parts are clear and the ejection apparatus of the mold is retracted. The robot then moves to the open press and positions the charge loader <NUM> into the cavity <NUM> of the mold <NUM>. The controller activates the loader dropping the charge into the mold cavity and retracts the loader from the mold.

Upon completion of the molding process and ejection of the molded cover from the mold, the robot includes a retractor <NUM> comprising a plate <NUM> and series of suction cups <NUM>. The controller opens the press at the correct cycle time and activates the cover ejection mechanism wherein the robot positions the retractor <NUM> over the molded cover so that the suction cups <NUM> can engage the cover and move the molded cover to a conveyor system <NUM> and releases the cover onto the conveyor system. The conveyor system then delivers the molded cover to a machining station <NUM> which includes a plurality of rotating brushes <NUM> to deburr the molded cover. The machining station also includes drilling holes for the vault attachment mechanisms.

Final assembly of the cover includes placing the pick hole rod in the recess of the pick hole cup and securing the cup and cap to the lid, securing the identification marker to the lid, securing the L-bolt, through bolt or self-latching mechanism along with the retaining flange and plugging the holes with caps for the attachment mechanisms not used.

Claim 1:
A mold (<NUM>) for molding a fiber reinforced polymer material utility vault lid (<NUM>) comprising:
a cavity die (<NUM>);
a core die (<NUM>) having a telescoping shear edge for interfacing the core die (<NUM>) within the cavity die (<NUM>), wherein the lid (<NUM>) is molded between the cavity die (<NUM>) and the core die (<NUM>); and
a lid ejection mechanism for removing the molded lid (<NUM>) from the mold (<NUM>),
wherein the cavity die (<NUM>) forms a textured surface (<NUM>) on an upper surface of the lid (<NUM>) having bosses (<NUM>) by having a pattern of features at different depths in a mold surface (<NUM>) of the cavity die (<NUM>), which pattern of features creates a protrusion into the surface (<NUM>) which pushes individual fibers (<NUM>) of the fiber reinforced polymer material utility vault lid (<NUM>) away from the upper surface to create a resin rich surface above the individual fibers (<NUM>).