Physical Description

Maynard's core business is the production of carbon and low alloy steel castings from 35 pounds to 65,000 pounds. Key to the ongoing success of the business is the flexibility of its processes and facilities.

Steel melting capabilities include four electric arc furnaces ranging in size from 14,000 pounds to 60,000 pounds. Furnaces are basic lined to facilitate steel refining and to enhance physical properties.

Pouring and molten metal treating is accomplished using bottom pour ladles ranging in size from 17,000 pounds to 80,000 pounds capacity. Larger castings are poured utilizing multiple ladles with a maximum pour weight achieved in excess of 100,000 pounds. The latest clean steel technology is utilized through the application of porous plug argon stirring and calcium, aluminum or titanium wire treatment.

Molds are prepared using both green sand and chemically bonded sand processes. Castings in smaller size ranges, typically 35 pounds to 2000 pounds, are produced in the green sand process on one of six molding centers. Chemically bonded molding processes are used for larger castings and selected smaller specialty castings where particular surface or dimensional requirements dictate. Ceramic tile gating systems and specialty facing sands are utilized extensively.

A wide' variety of flask sizes are available to meet a broad range of casting needs. Flasks range in size from 24"X24"-through 192"X 192" and 120"X240". A molding pit which is 288" wide, .312" long and 96" deep is also available.

Core processes include oil sand, shell, -C02 and no-bake. A variety of core making machines and techniques is available to support the molding centers.
 
Heat Treat and Finishing

 Extensive heat treating facilities are available at Maynard for normalizing, quenching, tempering, annealing, and stress relieving operations. Equipment is controlled by modern instrumentation. Furnace charts can be provided to satisfy heat treat documentation requirements.

Six car bottom furnaces are available, ranging in size from 15ft long X 8ft wide X 4ft high to 24ft long X 13ft wide X 12ft high.

Two free standing quench tanks are utilized, both with variable agitation and temperature controls.

The tanks are:

  • 7,500 gallons, l3ft long X 6ft wide X 12ft deep

  • 38,000, gallons, 24ft long X 17ft wide X 15ft deep

One continuous in-line pusher furnace is available featuring a normalizing oven, quench tank, and tempering oven. Unit is 72" wide with an under the door dimension of 18".

In addition to Maynard's own extensive heat treating capabilities, three outside contract heat treat shops are on our approved supplier list. These contractors are used for unique heat treating, 'size, or hardening requirements which are outside of our process scope.

Casting cleaning and finishing processes are capable of handling all castings produced. Five blast cleaning machines, some PLC controlled, are available. In addition, a directional blast machine is available for cleaning intricate cored passageways.

The finishing capabilities have been enhanced with the addition of a programmable robotic grinding cell. The cell performs grinding operations on castings approaching 500 pounds in weight.

 
Testing Capabilities
  • Mechanical Properties
  • Hardness
    • King machines with 16" throat capacity, and other stationary and portable machines.
  • Spectrographic
  • Oxygen/Nitrogen Determination
  • Radiography to ASTM E-446/E-186/E-280 Standards (subcontracted)
  • Magnetic Particle wet and dry to ASTM E-709/ E-125
  • Liquid Penetrant
  • Ultrasonics to E-609
  • Personnel qualified to ASNT SNT TC-1 A

Inspection Capabilities

  • Large layout tables
  • Portage digital layout equipment
  • Faro Arm with portable layout capability
  • Dimensional tolerances generally comply with SFSA Grade 5 or better
  • Visual surface standards inspected to:
    • SCRATA Tactile Comparator Plates
    • MSS SP55: A gage control system is documented.