AZ Automotive Weld Tooling & Assembly Equipment Standards  Revision 1.7    28Dec2004

PRINTED COPIES ARE UNCONTROLLED

Deviations that improve safety, quality, or cost ARE ALWAYS WELCOME.


SECTION 3

 

3.      Mechanical

 

3.1.             Design

 

3.1.1.                                   

All fixtures shall be equipped with a suitable means or attachments by which they may be lifted by Hilo for transportation and/or relocation.

 

3.1.2.                                   

Part loading must be error-proofed to prevent incorrect part loading.
Also see section 4.2.20. and 4.2.21.
It is the intention of these part detection methods to insure that an assembly cannot be produced that is missing a part due to machine malfunction or operator error.

3.1.2.1

Where fool proofing cannot be accomplished through mechanical means, AZ Automotive approved sensors shall be provided as required.

3.1.2.2

Single station, manually loaded and unloaded weld systems shall have an auto-eject mechanism.  Product exiting via auto-eject mechanism shall be delivered to a slide/chute by gravity and positioned so as not to interfere with operator load sequence.

 

3.1.3.                                   

Except for gun cylinders, all hydraulic cylinders will be AZ Automotive approved. All air cylinders will be AZ Automotive approved. Any deviation must be approved by AZ Automotive.

 

3.1.4.                                   

All pneumatic actuators shall be sized at 60 P.S.I. operating pressure. See Section Six for weld gun operating pressures.

 

3.1.5.                                   

Design source shall apply recommended standard components for gun and weld point build-up in all welding applications where possible. (See Section 6)

 

Counterbalance cylinders on lifter applications shall be sized to counterbalance 100% of the mass of the lifting device plus 50% of the total mass of the product at 60 P.S.I.

 

3.1.6.                                   

The following guidelines shall be used for sizing hydraulic actuators:

A.      Fixture motions and clamping at 450 P.S.I.

B.       Hydrostatic drive operating pressure not to exceed 1000 P.S.I.

 

3.1.7.                                   

All slug clearance holes shall be polished. Slug breakers shall be provided where necessary.  A slug removal system with detection is required.

 

3.1.8.                                   

All Cylinders to have booted rods to protect the cylinder rod from weld flash and minor abrasions.

 

3.1.9.                                   

Provide roller bearings or ball bushings when using guide shafts.

 

3.1.10.                                

Use McGill heavy stud sealed cam followers or equivalent.

 

 

3.1.11.                                

Cylinders shall be located in alignment with work slides and shall be installed so no side or radial load shall occur on piston rod.

 

3.1.12.                                

Provide substantial heel blocks to prevent side loading of press platen caused by weld gun and/or clamping pressures.

 

3.1.13.                                

All clamping must be normal to metal, and adjustable parallel to body lines.
Do not clamp two different surface planes with one clamp.

 

3.1.14.                                

Screw sizes in all areas must be substantial relative to application (5/16" minimum) and to the approval of AZ Automotive Design Coordination personnel.

 

3.1.15.                                

Helicoil inserts, or equivalent, are required in all tapped holes in nonferrous materials.

 

3.1.16.                                

Doweled details shall have provision for dowel removal utilizing a punch and hammer.
If blind dowels are unavoidable, they must be "pull dowels" with threaded provision for removal.

 

3.1.17.                                

Doweled details shall be retained with two (2) socket head cap screws, if space permits.

 

3.1.18.                                

Two dowels are required, however, one dowel is sufficient when using a heeled block.

 

3.1.19.                                

Bushings are required on all clevis-mounted cylinders.

 

3.1.20.                                

All tooling pivot pins shall be retained with two (2) screw keepers. Cylinder rod end clevis shall use rod end locks for anti-rotate. No cotter pins or tru-arc snap rings allowed.

 

3.1.21.                                

All gears and racks must be machined steel, castings are not acceptable. Rack lengths must allow for an additional travel of four inches (minimum) in both directions.

 

3.1.22.                                

Copper details subject to force on vertical walls must have a substantial cross section to back-up force (No copper castings are permissible).

 

3.1.22.1

Wedge machined pockets in copper electrode blocks that retain wedge clamps and electrodes shall have a minimum wall thickness of 3/8" inch.

 

3.1.23.                                

All slides shall have provisions for lubrication.

 

3.1.24.                                

All rotating machine elements (i.e.. pivots, dumps, swing units etc.) shall have sealed-for-life roller/ball bearings. Do not use bronze bushings.

 

3.1.25.                                

Deflection of the press crown shall not be more then 0.0015 inches per foot during any portion of the machine cycle.

 

3.1.25.1

Total weld gun force shall be checked against the capacity of the assigned machines.

 

3.1.26.                                

AZ Automotive approval is required for use of double rod end cylinders.

 

3.1.27.                                

Do not use set screws, roll pins, dowels or snap-ring retainers to secure locating pins (see NAAMS Assembly and Fabrication Book for securing locating pins, also see Illustration 3-25-0).

 

3.1.28.                                

All back-up blocks on primary and secondary show surfaces must be urethane and at least 2" wide.

 

3.1.29.                                

When using mechanical handling devices that have back-up blocks contacting primary and/or secondary show surfaces the material for the blocks must be a Shore "A", 80 Durometer urethane.

 

3.1.30.                                

Toggle lock mechanisms are not acceptable to absorb weld force. Wedge locks must be used.

 

3.1.31.                                

All machine bases, fixture base, fixture table, lower press platen, upper press platen must have machined "V" grooves per AZ Automotive Standards. (See Illustration 3-2.0).

 

3.1.32.                                

All locating pins to be adjustable (4) ways, hardened, and have a tapered lead. Use the NAAMS Assembly and Fabrication Book for locating pins where applicable.

 

3.1.33.                                

The minimum depth of tapped holes up to 3/4" diameter shall be (1.5) times diameter. 3/4" diameter and up shall be (2) times diameter.

 

3.1.34.                                

Do not counter bore screws unless absolutely necessary.

 

3.1.35.                                

When ordering square-head cylinders, specify stroke length in one (1) inch, (or 25 mm) increments through twelve (12) inches (or 300 mm) and two (2) inch (or 50 mm) increments for cylinders with strokes longer than twelve (12) inches (or 300 mm).

 

3.1.36.                                

For Hydraulic applications, Heavy-duty power wedge clamps are acceptable.

 

3.1.37.                                

Adequate ratios (See Illustration 3-4.0, 3-4.1, 3-4.2 and 3-4.3)

 

 

 

3.1.38.                                

Adjustments (See illustration 3-5.0)

 

3.1.39.                                

Bracket design (See illustration 3-6.1)

 

3.1.40.                                

Cylinders (See illustration 3-7.0)

 

3.1.41.                                

Fixture design for slide applications (See illustration 3-9.1)

 

3.1.42.                                

Pivot ratios (See illustration 3-10.0, 3-10.1, 3-10.2 and 3-10.3)

 

3.1.43.                                

Positioners (See illustration 3-11.0)

 

3.1.44.                                

Proximity switches (See illustration 3-13.0, 3-13.1)

 

3.1.45.                                

Shock absorbers (See illustration 3-15.0)

 

3.1.46.                                

Stops (See illustration 3-16.0)

 

3.1.47.                                

Stops, pins & screws (See illustration 3-17.0)

 

3.1.48.                                

Shuttle Rail Mounting (See illustration 3-18.0)

 

3.1.49.                                

Trunnion blocks & bearings (See illustration 3-19.0)

 

3.1.50.                                

Wires and Hoses (See illustration 3-20.0 and 3-20.1)

 

3.1.51.                                

The following guidelines for shafting material, heat treatment, & hardness when using Rulon Bearings:

DIA

Material

Heat Treatment

R.C.

.4995+.0000

          -.0005

 

.6245+.0000

          -.0005

 

.7495+.0000

          -.0005

 

Thomson 60 Case SAE 1061 Class "L"

Standard

60-65

1.000+.0000

          -.0015

 

12.500+.0000

            -.0015 

 

1.500 +.000

           -.002

 

2.000+.000

          -.002

 

2.5000+.000

           -.0025

 

T.G.P., &C. 1045-1050 .005 Chrome 6-16 R.M.S.

Standard

50-60 R.C. .03-.09 D.P. Chrome 68-70 R.C.

 

 

3.1.52.                                

All power clamps exposed to environmental contamination (weld splatter, sealer etc.) shall be of the enclosed design style.

 

3.1.53.                                

Full metric standards (wherever available and approved) will be used for the design and construction. This includes all fasteners (identifiable by a blue color). The only exception to this policy is steel stock sizes. Adhere to the Metric Design Standards as shown in the NAAMS Assembly and Fabrication Book.

 

3.1.54.                                

Standard shim packs (NAAMS) shall be used.

 

 

3.2.            Identification

 

3.2.1.                                   

All weld cylinders shall be identified with the same number as the weld. The balance of cylinders/ actuators (clamps, slides, etc.) shall have a unique letter designation (A, B, etc.) for non-unitized designs or for unitized designs a unique designation comprised of a unit number and letter (1A, 1B, 2A, etc.) for each particular cylinder on the mechanical drawing and the wiring diagram. All cylinders shall be physically tagged with that same number on the machine or fixture.

 

 

3.2.2.                                   

Stamp the tool number, property number, title, part identity, and the latest engineering change incorporated, on fixture identification plate in a conspicuous location on the fixture.

 

3.2.3.                                   

Stencil the tool fixture number and Direction-of-Flow arrow, if applicable in black or white paint on the fixture with 2" high characters.

 

3.2.4.                                   

For unitized tools stencil the unit number on the main detail of each unit in black or white paint with 1" high characters.

 

3.2.5.                                   

For the position name of horizontal devices see Section 4, Item 4.3.7.

 

3.2.6.                                   

For the position name of vertical devices see Section 4, Item 4.3.8.

 

 

3.3.            Construction/Installation

 

3.3.1.                                   

Any device that attaches to a support column or tube shall be attached by a sub-plate that is welded to the support column or tube.

 

3.3.2.                                   

All clearances for product radii, bosses, etc. shall have that clearance provided by machining the detail(s).

 

3.3.3.                                   

All weldments shall be normalized before machining.

 

3.3.4.                                   

The construction source shall operate all components manually, observing all clearances prior to sequencing the machine automatically.

 

3.3.5.                                   

The construction source shall supply guards around machine components that are subject to damage.

 

3.3.6.                                   

All pneumatic, electrical and hydraulic components must be mounted per approval of AZ Automotive Launch Technician and must be accessible for maintenance.

 

3.3.7.                                   

The construction source shall supply all manifolds, hoses, piping, wiring, etc., necessary to complete the installation of the fixture/system.

 

3.3.8.                                   

All clamp fingers shall be spotted to their respective back-up blocks with proper metal thickness in place. (Except for CAD/CAM applications)

 

3.3.9.                                   

All mounting brackets not shown on tool drawings shall be supplied and mounted by the Supplier in an approved manner.

 

 

3.3.10.                                

The construction source shall provide all necessary steel locating straps to expedite the re-assembly of the equipment at the receiving plant.

 

 

3.3.11.                                

Male threaded stud anchors are to be used for mounting to the floor.

 

 

3.4.            Mechanical Assist Device Guidelines

 

3.4.1.                                   

Mechanical assist device guidelines development phases

Please note, when referring to the mechanical assist device guidelines, that for each guideline, there is at least one, and sometimes as many as four, different phases of development for which that particular guideline is applicable. Those four phases of development are as follows :

 

1)       Mechanical Assist Device Design and Build,

2)       Design, fabrication and installation of support/header steel,

3)       Runway installation criteria and requirements and

4)    Equipment installation, tryout and buy off.

 

Please remember to pay careful attention to where in the development of the device each of the guidelines is applicable, and in cases where it is necessary to apply a particular guideline to more than one phase of development, to remember to do so.

 

 

3.4.2.                                   

MECHANICAL ASSIST DEVICE GUIDELINES

 

 

PHASES

1

2

3

4

No internal bearings design into the system. This provides for easier inspection and / or replacement

x

 

 

 

No offset loads from assist arm pivot without engineering deviation approval.

x

 

 

 

As built design shall include CAD drawings.

x

 

 

 

Paint dot (and safety wire on arms) all torqued, bolted connections, after torque verification. (Use bright florescent orange).

x

x

 

 

Define parallel / level tolerance for all runways. (No more than 0.125 inches in any 20-foot span).

x

 

x

 

Shall use all bolted construction. (No welded support steel connections).

x

x

x

 

If pitching the bridge system so that the tools move away from the moving conveyor when released is desired, use trolleys to accomplish this end.

x

 

x

x

Safety cable ALL single supported / bolted connections, as well as both ends of all runways.

x

x

x

x

Make standard a requirement for end cap protection on all bridges and runways. (Dual stops, cushions, shocks, etc.).

x

 

x

x

An end-of-travel design requirement shall be built into every original trolley rail and support steel design. (Sound warning 3 feet beyond work cell, and stop conveyor 3 feet after that).

x

x

x

x

Design concept and detail layout shall contain a provision for deployment of cables and / or hoses.

x

 

x

x

Minimum of 3/4-inch air line feed unless noted otherwise.

x

 

x

x

Facility air supply operating pressure will be assumed to be a minimum of 80 psi.

x

 

x

x

All trolleys shall be safety-chained or cabled to bridge rails, using standard, commercially available, materials.

x

 

x

x

Anti-Kickup trolleys will be standard for all process assist devices.

x

 

x

x

Splices and / or joint shall not impede free travel of bridge.

x

 

x

x

Inspection gates shall be provided as required on runways for ease of trolley maintenance and / or replacement.

x

 

x

x

Runway centers will be a minimum of 3 feet. Trolley centers on dual runways shall be a minimum of 3 feet.

x

 

x

x

Runway and trolley load data shall be provided on all as-built as well as all installation drawings and documents. This information shall also be entered in the assist device service manual.

x

 

x

x

FMEA’s on all manufactured components shall be supplied at concept approval stage and provided an all as built documents, as well as in the assist device manual.

x

 

 

x

All pivot mechanisms shall be fail-safe. All pivots shall be protected by a secondary safety device or owner-approved alternate.

x

 

 

 

All suppliers shall be registered with a recognized  aluminum welding association. (Documentation shall be provided in the assist device service manual).

x

 

 

 

Aluminum construction will be used only when absolutely necessary.

x

 

 

 

Both builder and installation contractor shall be licensed and inspected regularly to insure conformance to standard steel and aluminum welding practices.

x

 

 

x

All shop-welded components shall be tested for weld and component integrity, with the minimum test procedure being magna fluxing. Test results shall be included in the assist device manual.

x

 

 

 

All suppliers shall use existing AZ Automotive Standards, Do’s and Don’ts, and standard machining practices as per the Machinery Handbook.

x

 

x

x

Fatigue calculations and durability certification shall be provided for all components and weld groups.

x

 

 

 

All standard purchased components shall be chosen from the AZ Automotive  Approved source list.

x

 

x

x

Each specification shall include the Leo Oriet ergonomic guideline and checklist. (ref. Section 15.0)

x

 

 

 

Torque specification shall be supplied with each device and also listed in the assist device instruction manual.

x

 

x

x

Tractor and tracking brackets will be supplied on each bridge and be included as part of each design.

x

 

 

 

All designs shall incorporate ease of maintenance and repair.

x

 

 

 

3.5.            Lubrication

 

3.5.1.                                   

A lube layout sheet shall be supplied as a part of the controls design showing all auto lube systems and all manual progressive type lube systems.

 

3.5.2.                                   

Design shall insure lubrication of all friction points.

 

3.5.3.                                   

Each fixture containing (6) or more lube points shall be provided with lubrication that is manual series progressive self-metering with single point fault detector, Trabon or equivalent, (1) system per fixture with pump.

 

3.5.4.                                   

Fixed lines shall be steel tubing and flex lines shall be single-wire braid hose.

 

3.5.5.                                   

Sealed bearings do not require lubrication.

 

3.5.6.                                   

All grease lubrication lines, fittings, etc. shall be rated for a minimum burst pressure of 10,000 P.S.I.

 

3.5.7.                                   

It is not permissible to use one grease gun fitting to service more than one line unless using manual series progressive self-metering grease blocks with single point fault detection, Trabon or equivalent. (See illustration 3-23.0)

 

3.5.8.                                   

All grease lines shall be pre-packed before assembly.

 

3.5.9.                                   

Grease block (See illustration 3-23.0)

 

3.5.10.                                

Lubrication & bearings (See illustration 3-24.0)

 

 

3.6.            Safety

See Section 16

 

 

3.7.            Insulation

 

3.7.1.                                   

Insulate all rest, clamps or locators if they are within twelve (12) inches of a direct weld spot. If they are in the field of weld, they are to be made of brass, bronze or non-magnetic stainless steel. (The field of weld is defined as being any point located within three inches of the weld spot, weld electrode, electrode copper or welding cables). (See illustration 3-26.0)

In cases where the welder is DC or MFDC, more durable blocks, pins, rests, locators, etc., are to be used, such as NAAMS Standard Hardened Blocks. The DC field will not cause heating or eddy-current losses.

 

3.7.2.                                   

If the part is being insulated, make the insulating pads, bushings and washers from red fiber.

 

3.7.3.                                   

Removed

 

3.7.4.                                   

When insulating a slotted detail, use a clamp plate or flat washers to prevent distortion of the insulating washer.

 

3.7.5.                                   

Always make the length of the insulating bushing 1/64" less than the sum of the thickness of the insulating pad and the detail plus the insulating washer.

 

3.7.6.                                   

Use 1/16" thick insulating material for pads and washers and 1/16" thick wall on insulating bushings for static applications. The thickness of the insulation on moving joints will have to be considered on an individual basis consistent with good design practices.

 

3.7.7.                                   

No insulation is required on robot weld machines without hard tooling. Locating pins, locators, rest blocks and clamp fingers within three (3) inches of any robot weld must be made of brass, bronze or non-magnetic stainless steel.

In cases where the welder is DC or MFDC, more durable blocks, pins, rests, locators, etc., are to be used, such as NAAMS Standard Hardened Blocks. The DC field will not cause heating or eddy-current losses.