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Title:
STANDARDISED HINGE FOR FLATRACK CONTAINER
Document Type and Number:
WIPO Patent Application WO/2004/106678
Kind Code:
A1
Abstract:
A fabricated hinge, for mounting a folding (support) post (14) upon a platform base (11) of a collapsible f latrack container (10), features opposed f langes (27, 28), with differential flange depths to interface with a diversity of mounted post size and attendant tension or compression loading, whereby a common hinge format suits a diversity of mounted post and loading conditions.

Inventors:
Clive-smith, Martin (Wootton Paddox, Leek Wootton, Warwickshire CV35 7QX, GB)
Application Number:
PCT/GB2004/002276
Publication Date:
December 09, 2004
Filing Date:
May 28, 2004
Export Citation:
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Assignee:
Clive-smith, Martin (Wootton Paddox, Leek Wootton, Warwickshire CV35 7QX, GB)
International Classes:
B65D88/12; B65D88/52; E05D3/12; E05D5/06; E05D5/02; (IPC1-7): E05D5/06; B65D88/52
Domestic Patent References:
2003-07-31
Foreign References:
GB2361961A2001-11-07
GB412449A1934-06-28
GB2156425A1985-10-09
Attorney, Agent or Firm:
Tillbrook, Christopher John (Tillbrook & Co, 1 Mill Street, Warwick CV34 4HB, GB)
Download PDF:
Claims:
Claims
1. {Cooperative Bracing} A hinge with opposed flanges and intervening web, configured for mutual bracing with a flanged mounted element.
2. {Standardised Post Mounting Hinge} A standardised post mounting hinge, configured to accommodate post size variety, with mutual hinge and post reinforcement by constructive interface and load sharing between respective elements, such as flanges and webs.
3. {Flange Profile} A hinge of either preceding claim, of opposed flanges, and intervening web, with a flange profile to present a shoulder, for a diversity of mounted element span.
4. {Neutral Axis} A hinge of any preceding claim, of opposed flanges, with intervening web, wherein section bending stiffness and/or neutral axis disposition, such as in relation to tension load at one side and compression load at an opposite side, is determined by differential flange thickness, for more efficient material usage, without overall mass increase.
5. {Modular Hinge Lamination} A hinge of any preceding claim, of modular format, with laminated or multilayered opposed flanges and intervening web, with selective local thickness adjustment according to anticipated loading, and subject material strength, such as resistance to tension and compression, and whereby a common core hinge format can suit mounted element and loading diversity.
6. {Differential Hinge & Post Flange Depth} A hinge of any preceding claim, such as for post mounting upon a platform base of a flatrack container, the hinge comprising: relatively movable hinge elements, one hinge element for movable mounting having inboard and outboard flanges spaced by an intervening web, with differential flange section depth or thickness, to withstand local operational bending moments, such as applied through a mounted element.
7. {Sling Suspension Loading} A hinge for a folding post of a collapsible flatrack configured for sling suspension, imposing post bending loads, expressed in tension upon outboard post and hinge flanges, and compression, or compression offset by tension, upon inboard post and hinge flanges.
8. {Folding Post for Collapsible Flatrack} A folding post for a collapsible flatrack mounted upon a platform base by a hinge of any preceding claim.
9. {Flatrack with Folding Posts} A flatrack with folding posts of the immediately preceding claim.
10. {Flatrack with Hinged Posts} A flatrack with folding corner end posts mounted upon a platform base by hinges of any preceding (hinge) claim.
Description:
Standardised Hinge for FlatRack Container This invention relates to so-called collapsible flatrack containers for freight transport and storage.

Generally, such a flatrack comprises a rectangular platform base with folding posts and/or end walls.

Posts are typically disposed at corners, as corner end posts.

That said, intermediate posts can be located inboard of the flatrack base span.

Posts and/or walls are mounted by hinges upon the base.

One (fixed) hinge element can be secured to the platform base and another (movable) hinge element to a post or wall.

Hinges can be locked-say, by inter-coupling fixed and movable hinge elements-so that in an erect upright position posts and/or walls can be used for stacking and racking with other containers.

Upon hinge unlocking, posts and/or walls can fold down flat upon the platform base, for compact, economical storage and transport.

There are various types of collapsible flatrack to meet differing requirements- including 20ft and 40ft lengths or (longitudinal) spans.

A larger, say 40ft, span flatrack requires a very much greater platform base depth and strength, as compared with, say, a 20ft span.

Likewise post and end wall dimensions can reflect geometric and strength requirements of different flatracks.

Hinge Modification Thus hinges must suit particular post and base structures.

Conventional hinge constructions have not lent themselves to adaptation to different requirements.

Slender Corner Posts One requirement for 20ft flatracks is very slender corner posts, to maximise intervening side openings, for (unobstructed) cargo access and placement.

Robust Corner Posts In another flatrack type, more robust and so bulkier corner posts might be required, to withstand high racking forces, or to meet other enhanced strength or rigidity requirements.

Demand Prediction With such a variety of different hinges in a small niche flatrack market, it is difficult to anticipate which of the many hinge varieties to manufacture or stock.

Non-Standardisation Furthermore, since hinges are not standardised, economies of scale in manufacturing cannot be achieved so they are more expensive-and cannot be held in stock for just- in-time delivery.

Lead Times Thus hinge production lead-times for a new flatrack order can be very extended, while jigs and fixtures are adjusted and different materials brought in.

Common Hinge Configuration A common hinge configuration-strong enough to meet the most demanding requirements and yet compatible with bases and corner posts of any reasonable size- would thus be desirable.

Prior Art In PCT/GB2003/000146-WO 03/062100 Applicant teaches a fabricated hinge of composite opposed flange, intervening web and bracing elements-for post mounting upon a flatrack.

Relative disposition of hinge and mounted post elements-in particular hinge and post flange interface-is considered.

However, hinges are bespoke to circumstances.

One aspect of the present invention addresses commonality of hinge construction or hinge element componentry-for compatibility with a diversity of mounted post sizes and platform base integration.

Another aspect of the invention addresses hinge adaptation to flatrack sling suspension from upper ends of support posts-and in particular material (re-) deployment better to meet post and hinge bending loads and attendant shear stresses.

Statement (s) of Invention According to one aspect of the invention, a hinge with opposed flanges and intervening web, is configured for mutual bracing with a flanged mounted element.

According to another aspect of the invention, a standardised post mounting hinge, is configured to accommodate post size variety, with mutual hinge and post reinforcement by constructive interface and load sharing between respective elements, such as flanges and webs.

A hinge of opposed flanges, and intervening web, could thus feature a flange profile to present a shoulder, for a diversity of mounted element span.

In a particular construction, a hinge for a mounted element, such as a folding end post and/or wall of a flatrack container, comprises: one element for attachment to mounted element, and another element for attachment to a base, the elements being pivotally connected, (inter-) lockable, and the one element (mutually) reinforced by mounted structure.

Mutual Reinforcement-Flange Juxtaposition Co-operative mutual reinforcement of a hinge element and mounted element can be contrived through juxtaposition of respective flanges and webs in a fabricated construction.

Flange Depth Moreover, (hinge) flange depth or cross-section can be adapted to local loading demands.

Flange Orientation For an'I'-beam (mounted) post section, opposed side flanges may be orientated

transversely of deck planform, with an intervening web orientated longitudinally thereof.

That said, other dispositions might be contemplated to address particular constructions and loading.

Hinge Axis The hinge axis is generally transversely of the deck planform and orthogonal through mutually overlapping hinge element webs.

A hinge pin is set between inner and outer hinge elements-with an offset disposition to achieve desired hinge and mounted post movement action.

Hinge elements can be configured as'L'-shape frames or plates, with upright and (inboard) lateral limbs to present an inboard hinge pivot axis.

Post and/or end wall hinge action can then lift a post and/or wall clear of its seat and over a platform base deck plane.

Similarly, a hinge lock can interact between inner and outer hinge elements-say upright plate limbs-at a position outboard of the hinge axis, so preserving a seated post and/or wall position when engaged.

Racking Loads Under stacking and handling, posts are subjected to racking and shear loading or bending stress.

Similarly, (longitudinally) opposed (I-section) post and hinge flanges are subject variously to compression and tension loading.

Sling Loads Suspension loads imposed by a handling sling between opposite end walls and associated posts tend to bend posts and walls inwardly together.

Flange Loading 'Inboard'post flanges are subject to compression and'outboard'post flanges to tension.

Here'inboard'and'outboard'refer respectively to longitudinally inward and outward facing flanges.

Local Section Changes Material employed may be better able to withstand, say, compression than tension-in

which case sections subject to tension may be increased, whilst sections in compression reduced.

This is in the interests of keeping overall weight down, by concentrating material where required-whilst preserving bending stiffness and rigidity.

Overall post sections, opposed flange depths and intervening web span may be determined by anticipated (bending) loading.

In principle, similar considerations might apply to hinge element profile-but for the desirability of a common hinge format adaptable to post diversity.

Flange Depth Thus for an'I'-section outer hinge element profile, of fixed web span, careful choice of opposed flange depth is required.

Given that-for a range of container sizes-inboard post and hinge flanges are compression loaded under sling lift, and which their material is better able to withstand, they might be reduced in depth.

[Indeed, an inboard (post or hinge) flange might be reduced (ie thinned or slimmed down) -or even be omitted altogether-in favour of, or in deference to, a corresponding thickened (hinge or post) flange.] Neutral (Bending) Axis A post or hinge element overall section has a neutral axis under bending, at the transition between compression at one side and tension at the other.

Respective opposed flange depths, relative spacing or intervening web span, impact upon bending stiffness and neutral axis disposition.

Neutral axes of post and hinge reflect respective section profiles-and in that sense are independent.

However, for post and hinge element integration, a combined overall neutral axis arises.

Neutral axis (re-) disposition for different opposed bounding flange depths and relative dispositions, or intervening web spans can be factored.

Shared Flange A flange on one element can contribute to stiffness of another element to which it is joined.

In that sense, flanges can be shared between joined elements-or one element can

be reliant upon the flange of another.

Fixed Hinge Configuration + Variable Post Span If the span and flanges of one element-say hinge-are fixed, in the interests of standardisation, variability of another conjoined (post) element can be admitted by such shared loading considerations.

More specifically, different post spans can be conjoined to a fixed hinge element.

Thus a post web can be secured upon contact with fixed span hinge flanges.

Post span is thus unconstrained by fixed hinge span.

Thickened Hinge (Outer) Flange Moreover a thickened outer hinge flange-to counter tension loading under sling lift- can contribute to overall stiffness of a hinge mounted post, even absent an outer post flange.

Differential Post & Hinge Interface By careful selection of flange sizes and relative dispositions, effectively a common')'- beam outer hinge element can interface or merge with different size'I'-beam post sections.

Mutual Bracing For mutual bracing, either mutual overlap or shared outer post and hinge flanges can be contrived.

Hinge + Post Flanges Thus, a depending inboard post flange could extend to a hinge sloping inner flange or web shoulder-effectively creating a double juxtaposed inner flange.

A conjoined or integrated outboard post and hinge flange preserves a container outer span standard.

For different post widths, and attendant flange spacing and intervening web span, post flanges could extend to a different hinge flange or web shoulder contact position.

In practice, hinge and post joining is by welding flanges of one element to the web of another to achieve a cross-braced overlap or intersection.

The foregoing applies primarily to a movable (outer) hinge element and mounted post.

Similar considerations could apply to a fixed inner hinge element, but diverse deck beam sizes and configurations offer greater scope for mutual contact reinforcement within the deck depth.

Post Sections Although emphasis has been upon'I'-beam sections, diverse configurations are tenable, such as box sections-albeit even if not so readily fabricated in bespoke formats.

Conventional Hinge In contrast, a conventional hinge construction may simply rely upon an unbraced butt joint between post lower end face and outer element upper face.

Asymmetric Section Augmentation Another aspect of the invention provides asymmetric post and hinge section augmentation, by adoption of heavier outer flange depth or section, better to resist tension loading under sling lift.

Differential Flange Thickness In a particular construction, a thickened outboard flange and lighter inboard flange-ie differential flange thicknesses-can be employed.

In this way, overall section stiffness and neutral axis disposition can be preserved for conjoined post and hinge elements.

Neutral Axis Movement Otherwise, for a wider post upon a given hinge section, the neutral axis moves inboard with the post inboard flange-given respective outboard post and hinge flanges remain aligned, to preserve overall container standard span.

This in turn means an effective loss of overall strength, bending stiffness or rigidity.

Inefficient/Redundant Material in Element Section Moreover, neutral axis shift means inefficient use of material to withstand loads imposed-with redundant material bulk at element section positions where less critical compression loads experienced.

Standard Pivot + Locking Pin A standard pivot and locking pin can be employed for a diversity of post sizes, given

an adaptable interface between respective flanges and webs.

Thus, a'lowest common denominator'or'highest common factor'approach can be taken to shared hinge componentry compatible with post diversity.

Embodiments There now follows a description of some particular embodiments of the invention, by way of example only, with reference to the accompanying diagrammatic and schematic drawings, in which...

Figure 1 shows a simplified perspective view of a collapsible flatrack container with hinged end (corner) posts and walls ; Figure 2 shows a side elevation detail of a conventional known hinge for a flatrack of Figure 1; Figure 3 shows local enlarged local detail of a hinge embodiment of the invention; Figure 4 shows a hinge abutment stop for the hinge of Figure 3; Figure 5 shows a variant hinge abutment stop to that of Figure 4; Figures 6A through 6C reflect hinge and post elements under sling suspension loading; Thus, more specifically...

Figure 6A shows-through section and associated scrap elevation-disposition of a notional neutral (bending) axes respectively for individual and conjoined hinge and post sections; Figure 6B shows a neutral axis considerations for a variant of Figure 6A with differential hinge flanges; Figure 6C shows the disposition of tension and compression loads upon flatrack end walls and hinge mountings through sling lifting; Referring to the drawings...

Figure 1 shows a perspective view of a typical collapsible flatrack 10, comprising a platform base 11, with an infill deck or floor 13, such as of timber planking, surmounted at opposite ends by inward folding end frames or walls 12.

Each end frame 12 has, or is set between, paired corner end posts 14, mounted upon platform base 11 by hinges 15.

Figure 2 shows a close-up side elevation of conventional hinge 15, with post 14 locked upright.

This is a typical hinge of known manufacture, with an inner hinge element 17 attached to post 14, and an outer hinge element 16 attached to base 11.

In a bottom (right hand as depicted) corner is installed a corner fitting 37, of standardised format for container capture, handling and stacking interfit.

Corner fitting 37 comprises a cast rectangular box with handling apertures 18 in its outermost sides, along with a bottom aperture to receive a standard so-called'Twist- Lock'capture device (not shown).

Depth'd'of post 14 matches depth'e'of inner hinge element 17, so that a weld can conveniently be made where post 14 overlaps hinge inner element 17, as indicated by a cross-hatching 19.

Outer hinge element 16 is similarly welded to corner casting 37 along cross-hatching 20 to complete the structure.

An offset inboard pivot pin 21 allows post 14 to fold, about an arc'a', to lie down upon platform base 11.

A locking pin 22 passes through mutually aligned holes in inner and outer hinge elements 17,16 to inhibit post fold until release by pin 22 withdrawal.

The hinge assembly shown in Figure 2 is of typical proportions for a 20ft flatrack.

As such, hinge outer depth dimension'f'is between the underside of corner casting 37 and a top plate 23 which surmounts outer hinge element 16.

For a 40ft flatrack construction, hinge outer depth'f'must be increased to'f"to accommodate a much deeper platform base 11'.

Likewise, corner post depth'd'might well be increased to'd", to accommodate greater racking forces that might be imposed upon the flatrack 10.

However, neither new corner post 14', nor platform base 11', suit existing inner hinge element 17, or outer hinge element 16 (in relation to hinge fold orientation towards deck 13).

Figure 3 shows an alternative arrangement of hinge inner flange 17 shaped to suit a slender post 14, such as of Figure 2, and yet comfortably receive a larger (wider depth /span) post 14'.

Post 14'has back (outboard) flange 24 and front (inboard) flange 25, with an intervening web 26, to form an overall l-section beam.

Inner hinge element 17 has a back (outboard) flange 27 and a front (inboard) flange 28, with an intervening web 29.

Pivot pin 21 and locking pin 22 are retained to act through web 29, with respective mounting trunnions braced by flanges 27,28.

Flanges 24,25 of corner post 14'envelop or embrace the span of inner hinge element 17.

Thus back (outboard) flange 24 overlaps back flange 27 of inner hinge element 17.

Similarly, front (inboard) flange 25 overlaps front flange 28 of inner hinge element 17- and extends down towards a lower part of flange 28.

By welding flange 28 to web 26 and flange 27 to web 26-and optionally also by welding a spacer 30 to join flanges 27 and 24-post 14'reinforces inner hinge element 17 structure, of flanges 27,28 and web 29.

Furthermore, web 29 may terminate where it meets web 26 at line 31.

Had corner post 14'been formed as a slender corner post 14, flange 25 might have been located as 25', as shown in broken outline falling close to, or in line with, flange 28.

Thus-provided pivot pins 21 and locking pins 22 are capable of supporting racking loads imposed upon them through corner posts 14 or 14'-a variety of corner posts 14, 14'sizes can be fitted to a common format compact hinge inner 17.

Effectively, flanges 24,25 of mounted post 14 extend down over a standard size inner hinge element 17, as reinforcement.

Figure 4 shows outer hinge element 16, with a top plate 23, locking pin 22, and pivot pin 21.

A broken line represents a hinge inner element 17 in an (upright) erect (post 14) position.

Line 32 shows a recess 33 where a corner casting 37 might be accommodated for a shallow-base flatrack.

An extension stool 34, with a bottom line 35, has a recess 36 (to mimic recess 33) to receive a corner fitting 37.

A platform 11'of greater base depth is welded to outer hinge element 16 and stool 34.

Stool 34 is welded to hinge outer element 16 along line 32 into recess 33.

Additional reinforcement can be provided-such as a plate 38 connecting (by welding) outer hinge element 16 to stool 34.

Platform 11'has side rails 39 comprising bottom flange 40, top flange 41 and an intervening web 42 joining flanges 40,41 to form an l-section beam.

Outer hinge element 16 typically comprises parallel plates 43 and 44.

Plate 44 is of similar profile to plate 43, but projects somewhat above it, to connect with top flange 41.

Whereas stool 34 connects to plate 43, it is envisaged that plate 44 might terminate along its line 32-with optional connection by plate 45 (depicted in broken line) to web 42 and the rest of base 11 structure.

Reverting to Figure 2, inner hinge element 17 is under greatest stress from racking forces acting on post 14 where it passes through top plate 23.

Inner hinge element 17 must be narrowed to fit through top plate 23, yet not enlarged on the inboard side towards platform base 11.

This is to maximise cargo spacing'g'between opposite post 14 faces.

Thus, where corner posts 14 of somewhat greater depth'd"can be accommodated- albeit sacrificing cargo space in favour of extra racking strength-inner hinge element 17 depth'e'can be increased, by extra plating, or by extension of corner post 14' through top plate 23 line h-h.

Figure 5 shows an arrangement substituting locking pin 22 of Figure 2 with a rectangular locking pin or detent 50, supported within inner hinge element 17 by a'C' profile (throat) block 51, having a heel 52 upon which pin 50 bears.

Block 51 is connected to flange 27 by an overlapping connection 54, in this case configured as a clevis, so maximising a weld connection 53 to flange 27, better to withstand racking forces imposed upon the flatrack 10 through the corner post 14.

Figures 6A through 6C reflect differential flange loading and profiling to address sling lifting, depicted in Figure 6C.

Figures 6A and 6B are sections along the line x-x in Figure 6C, for different hinge and post formats.

A sling 61 draws together the tops of opposed corner end posts 14, with a transverse inward bending force component.

This in turn imposes tension loading upon outboard post flanges 24 and associated hinge flanges 27.

Such bending tension load adds to tension from a vertical lift component-creating a doubled tension effect upon outboard post and hinge flanges.

In contrast, the inboard post and hinge flanges experience a tension from a vertical lift component, countered by a compression from inward bending.

There is thus a marked disparity between inboard and outboard post and hinge flange loading-and which it would be desirable for material disposition to reflect.

This even more so given greater flange material resistance to compression than bending loads.

That is, post and hinge material (typically steel) tensile strength is less than its compressive strength.

Thus some inboard flange 25,28 depth reduction in favour of outboard flange 24,27 depth increase can be countenanced.

Effectively, that means a judicious re-disposition of material for optimum effect without a penalty of increasing overall structural mass, which would reduce payload.

Figures 6A and 6B express such considerations in terms of a notional neutral bending axis for a hinge alone and a hinge and post combination.

Hinge neutral axis location reflects an interpolation between bounding flanges 27,28.

Thus a hinge section with symmetrical flanges has a neutral axis at its geometrical centre line-or axis of symmetry.

Figure 6A depicts a juxtaposed post and hinge and individual hinge and combined post and hinge neutral axis (re-) disposition.

Combined post and hinge neutral axis is related to all contributory flanges and is referenced 25,27, 28.

The effect upon combined neutral axis disposition of a post span increase-upon inboard (compressive-loaded) flange 25 relocation to 25'-is also to move combined neutral axis 25,27, 28 inboard.

This means inefficient use of material as the inboard (of neutral axis) mass equates to that outboard, yet the outboard mass is more critically tension loaded.

In this analysis, outboard post flange 24 is (temporarily) disregarded, but is notionally constrained with outboard hinge flange 27, for prescribed standard overall container span.

That is there is only scope for post 14 span increase by inboard flange inward re-

disposition.

Hinge span is fixed by a requirement for a common hinge construction for different post 14 sizes.

Figure 6B depicts that by increased outboard hinge flange depth 27'and reduced inboard flange depth 28', hinge neutral axis is displaced outwards.

Increased post span displaces combined neutral axis 25,27', 28'inwards, but still somewhat outboard of original combined neutral axis 25,27, 28.

Put another way, inboard post flange movement with increased post depth is countered by greater massing of outboard hinge flange depth-just where greatest tension loading is experienced.

Figure 6B reflects inboard flange depth reduction (somewhat), without adverse effect.

Moreover, increased outboard flange depth can be achieved by shared or mutually additive hinge and post outboard flange depths.

Thus thickened outboard flange 27'of Figure 6B could be shared between hinge and post.

Overall, material is placed where it is best utilised-for optimised weight and strength efficiency.

To summarise overall : Sling Lift Suspension Such sling lift suspension considerations dominate container handling and post loading considerations.

Post Bending Post bending stiffness reflects sectional shape and size-and in turn flange depth and spacing.

The neutral axis reflects a transition line between bending and compressive loading.

Post or hinge (flange or web) mass inboard of the neutral axis is inefficient, as it does not contribute to resisting tension loading.

Compression loading is more readily resisted with minimal structure inboard of the neutral axis.

Modular Hinge Posts and/or hinges may be adapted to local loading requirements.

Thus, notwithstanding the desirability of a single hinge format, say, relatively heavy and light spectrum hinge variants might be contrived.

Thus, say, if one end wall is heavier than another-such as might arise by fitting a movable end gate rather than passive infill, associated corner end posts and hinges might be a heavy spectrum variant.

A limited modular hinge range might be contrived.

Even this might be fabricated with a large common component count, with local reinforcement by, say, plate overlay or doubling up.

Lamination With this objective, flange and web templates could be contrived, allowing lamination or stacking.

This in turn could allow laminations to be relocated from lower to higher stress locations, such as to meet tension vs compression loading at outboard vs inboard flanges under sling lift suspension.

Bridge An intermediate bridge fitting might be employed for hinge-to-post interface geometry and loading.

Mix and Match Whilst it is not practicable to show every feasible combination and permutation, various features identified may be selectively'mixed-and-matched'to meet particular requirements.

In that regard, posts could differ, say, between base ends, to reflect respective end wall mass.

Moreover, the Applicant has proposed a dual standard container format with paired posts at respective standard spans-and for which different post sizes might be appropriate.

This is particularly so if paired posts are used co-operatively to share, say, sling or racking loads.

Claim Reference Phrases in brackets vis {...} alongside claim numbering are merely for ease of reference-and as such themselves do not form part of claim scope or interpretation.

Component List 10 (collapsible) flatrack 11 base 12 (folding) end wall/frame 13 platform deck 14 corner (end) post 15 hinge 16 outer hinge 17 inner hinge 18 handling aperture 19 weld 20 weld 21 pivot pin 22 locking pin 23 top plate 24 back flange 25 front flange 26 web 27 back flange 28 front flange 29 web 30 spacer 31 line 32 line 33 recess 34 extension stool 35 bottom line 36 recess 37 corner fitting 38 plate 39 side rail 40 bottom flange 41 top flange 42 web 43 plate 44 plate 45 plate

50 rectangular locking pin 51'C'profile block 52 heel 53 weld 54 connection 61 suspension sling