12/02/13 Rice husker construction manual - Appropedia: The sustainability wiki

www.appropedia.org/Rice_husker_construction_manual 1/17

Rice husker construction manual 0 Curtir Seja o primeiro de seus amigos a curtir isso.

From Appropedia

An individual thinks that this page could have wiki-mark-up applied.

Ingénieurs Assistance Internationale - Ingénieurs sans Frontières

Construction manual of a rice husker Equipment designed and manufactured inHaiti by the workshops-schools of Camp Perrin

Developed in cooperation with Codéart and the workshops-schools of CampPerrin

Philippe Carlier (†) Cédric Vanhoolandt Project engineer ISF Construction manual

of a rice husker [1] Equipment designed and manufactured in Haiti by theworkshops-schools of Camp Perrin

Collection "Technical manuals" Manual created by ISF with support of the GeneralDirectorate for Cooperation and Development (DGCD)

Ingénieurs Assistance Internationale - Ingénieurs sans Frontières 2003http://www.isf-iai.be mail@isf-iai.be Avenue du Marly, 48, 1120 Brussels -Belgium

We thank all the people without whom this manual could have not seen the lightof day, and in particular: the members of the workshops-schools of Camp Perrin,Roger Loozen (Codéart) and Michel Taquet (GRET).

Technical sheet Production schedule: 250kg/h for a recommended motorization of

12/02/13 Rice husker construction manual - Appropedia: The sustainability wiki

www.appropedia.org/Rice_husker_construction_manual 2/17

15CV (~ 11kW) Training: only the manual Use: business use; for small ormedium communities Maintenance: lubrication of bearings, regular maintenanceof engine, replacement of worn parts: drums and knives Features: low costmanufacturing, simple manufacturing techniques, robust

Contents

1 Introduction2 Principle of operation3 The manufacturing of the huller

3.1 Bill of materials3.1.1 Manufactured parts3.1.2 Standard Parts

3.2 Identification of the different sets3.3 Support3.4 The lower body

3.4.1 The lower body3.4.2 The clamp closure3.4.3 The knife of the huller3.4.4 The knife support3.4.5 The adjustment screw for the knife3.4.6 The tightening of the sieve support3.4.7 The sieve support3.4.8 The sieve3.4.9 The maintenance bar for the sieve

3.5 The rotor3.5.1 The axis3.5.2 The primary hulling cylinder3.5.3 The secondary hulling cylinder3.5.4 The pulley drivetrain3.5.5 The attaching of the pulley3.5.6 The nuts of the primary and secondary dehusking cylinders3.5.7 The bearings

3.6 The upper body3.6.1 The supply hopper3.6.2 The upper body3.6.3 The supply mouth3.6.4 The exit mouth

3.7 Parts to buy3.8 Drivetrain3.9 The production of the templates

4 Maintenance5 Bibliography6 Appendixes7 References

Introduction

This guide is intended for all workshops wishing to put in place the

12/02/13 Rice husker construction manual - Appropedia: The sustainability wiki

www.appropedia.org/Rice_husker_construction_manual 3/17

manufacturing of a rice husker, adapted to the constraints of non-industrialisedcountries.

The rice husker described in this manual is based ona model that has proved its worth for many years;notably the Engelberg rice husker (see Annex 5). Thehuller is successfully produced in Haiti since 1994 bythe workshops-schools of Camp Perrin (AECP). Thesetwo elements assure the huller of being welladapted to the constraints of most countries, wherethe technical expertise is limited, both in regards tothe manufacturing as the use. Also, numerousarguments plead in favor of local production:

In case of machine failure or wear, spare partscan be easily found and are thus available in atimely manner;Manufacturing of the huller provides handworkfor the locals;A transfer of pre-industrialised techniques isdoneProduction costs for the machine are lower,which permits the wider distribution of a machine that is beneficial to thecommunity;A pre-industrial technology transfer takes place, marking the first step for ashift towards serial production

This model of huller has many parts made in a foundry. Unfortunately, manyworkshops do not posses this technology. In this case, the best solution is tolocally outsource these parts. If this solution also not possible, all these partscan be ordered from the Belgian A.S.B.L. Codéart 2. A version of this machinemade solely from mechanical welded parts is currently being researched. Wewarn the reader about the apparent simplicity of the huller: its manufacturingdemands hefty experience and mechanical know-how.

The manual includes not only the detailed drawings of all parts of the huller, butalso those of all the special tools used for their manufacturing: templates forpiercing, foundry molds, ... The tools described in this manual are those alsoused at Camp Perrin, but may be adapted depending on the tools or othermaterials available in your workshop.

The huller described here is a horizontal axis model. It is equipped with anengine (diesel or electric) with a performance of about 250kg/h for amotorization of around 15CV, thus about 11kW.

The product obtained by the rice farmer is not inmediately usable for humanconsumption:it is the "paddy" rice or "Dressed" rice. The grain of the rice, or"caryopsis", to be eatible, must be removed from its envelopes that cover it (seediagram in Annex 4). Through this operation, we obtain "husked rice" or "brownrice" when it is complete, as well as a byproduct.

1 Workshops-schools of Camp Perrin - BP 183 Les Cayes - Haiti info@aecp-haiti.org 2 Codéart ASBL - Chevémont, 15 - Homburg 4852 - Belgium Tel: +32 /

12/02/13 Rice husker construction manual - Appropedia: The sustainability wiki

www.appropedia.org/Rice_husker_construction_manual 4/17

Rice husker connected to a

motor

87 78 59 59 - Fax: +32 / 87 78 79 17 www. codeart.org - info@codeart.org

When the we dehusk the rice, we first remove thehard envelopes. Then we take on the thinner ones.Through this process, the rice slowly changes color,and when it is complete, it is brown. Whencompletely shelled, the rice is white. Commercially,husked rice is called "cargo rice".

The rice husker performs the shelling of (separationof glumes and bracts) and laundering or elaboration(separation of the different layers of pericarp) in asingle operation. It is therefore not possible toseparate the two by-products, namely the chaff(glumes and bracts) and the bran (pericarp). As aresult, despite the high nutritional value of the bran(rich in vitamins B and E and other nutritionalelements; see the table of nutrient values in Annex4), the by-products can not be used to enrich thesoil or to mulch the treenurseries. Indeed, the chaffis unfit for animal consumption because it maycause irritations and bleedings in the intestines.

To avoid loss of important nutrients, it is possible to steam the rice. From atechnical perspective, drying is a precooking process of the pre-hydrated paddyrice with a water content of around 30%. Steaming improves the technicalquality of the rice (cost-effectiveness of shelling) by resolving the cleavedgrains, thus reducing the margin of broken rice. It causes some yellowing of thegrain as the heat treatment is more or less pronounced. It also increases thenutritional qualities by enriching the kernel with B-vitamins and minerals thatwere initially concentrated in the pericarp 3. Milled, parboiled rice also has ahigher vitamin content than raw milled rice.

At the exit of the huller, the rice is only partially bleached. It could be allowedto pass through a second time in the machine to get a grain which is a bitwhiter. This operation is however not recommended because the more time thegrain spends in the machine, the more is wasted from the rice, and a largeramount of nutritional value is lost. Some more complex machines separateglumes and bracts before entry into the polishing drum where the bran isseparated from the grain. A machine which allows this separation of the chaffand the bran is currently being researched by Codéart. A prototype is alreadybeing tested. This machine can easily be mounted on the huller described in thismanual. The function of the huller is then limited to separating the bran of thegrain after which the chaff is separated in a next step.

3 J.F. Cruz and Souare D., 1997.

Principle of operation

When the huller runs, we introduce rice into the hopper. The part of the rotorwhich is located below the hopper acts as an Archimedes screw, and "pushes"

12/02/13 Rice husker construction manual - Appropedia: The sustainability wiki

www.appropedia.org/Rice_husker_construction_manual 5/17

General operation of the

rice husker

the rice to the other end of the rotor. Once some of the rice has passed into thebody of the huller, it is driven by the horizontal stries of the central part of therotor into a rotational movement.

When the grains of the non-husked rice arrives atthe knife, the space it has to move along (betweenthe rotor and the knife) is heavily reduced. The knifeopposes the rotation of grains. The chaff and thebran surrounding it then "rub" along the edge of theknife and the elevations of the rotor, leading to theirseparation of the grain by necking and scouring. Thisallows the husking of the rice. The level of scouringis set by the opening of the exit for the husked rice:the more it is closed, the more the rice is forced tostay longer in the device, which accentuates theshelling. The pieces in which the bran and the chaffare cut, are small enough to pass through the sieve.

While revolving around the rotor, the rice also advances towards the exit, drivenby the rice still located in the feed hopper. Once it arrives at the exit, it canescape through an opening with a especially for this purpose created form. Theposition of the release is placed relatively high, which allows the last separationbetween the rice and the chaff which has not yet been evacuated by the sieve.The grains of the rice, because of its weight, is projected onto the exit byinertia. The lighter chaff remains in the body of the huller and continues to turnuntil exits through the sieve. This separation allows to not require thewinnowing (separation of dust and remaining waste) of the rice produced by thishuller.

Location of the cuts

12/02/13 Rice husker construction manual - Appropedia: The sustainability wiki

www.appropedia.org/Rice_husker_construction_manual 6/17

open huller

Cut A-A

The manufacturing of the huller

Bill of materials

Manufactured parts

Qty. Number Name Material Standard 2 00-001 hingesteel St 37 2 01-001 angle back foot steel St 37 101-002 angle forward left foot steel St 37 1 01-003angle front right foot steel St 37 2 01-004reinforcement sheet steel St 37 2 01-005 flat steelbody support steel St 37 4 01-006 flat steel groundfixation steel St 37 1 01-006 angle left spar steel St37 1 01-008 angle right spar steel St 37 1 01-009front sheet steel St 37 1 01-010 rear sheet steel St37 2 01-011 crossed angle steel St 37 1 02-001lower body cast iron FGL 250 2 02-002 closing clampcast iron FGL 250 1 02-003 hulling knife Ac with spring 5ISi7 2 02-004 knifesupport cast iron FGL 250 2 02-005 adjustment screw for knife steel Ck45 3 02-006 sieve clamping support cast iron FGL 250 3 02-007 sieve support cast ironFGL 250 2 02-009 sieve maintenance barette steel 1 03-001 axis diameter 2*h7steel Ck45h7 1 03-002 primary hulling cylinder white iron 1 03-003 secondaryhulling cylinder white iron 1 03-004 drive pulley cast iron FGL 250 1 03-005 nutprimary cylinder cast iron FGL 250 1 03-006 nut secondary cylinder FGL 250 1 03-008 end key DIN 6885-A 12x8x120 steel 1 03-009 central key DIN6885-A12x8x56 steel Ck 45 1 04-001 supply hopper steel St 37 1 04-002 upper bodycast iron FGL 250 1 04-003 feeding mouth cast iron FGL 250 1 04-004 exit mouthcast iron FGL 250 1 04-005 steel exit control sheet St 37 1 04-006 closure exitsheet steel St 37 1 04-007 closure supply sheet steel St 37 4 joint-axis body felt

12/02/13 Rice husker construction manual - Appropedia: The sustainability wiki

www.appropedia.org/Rice_husker_construction_manual 7/17

huller assembly

Note: See the table of standards of metals in Annex 3.

Standard Parts

Qty. Designation Material Standard 8 washers M6 steel DIN 125 A 4 washers M8steel DIN 125 A 15 washers M10 steel DIN 125 A 6 washers M16 steel DIN 125 A4 ankle diam.10 x 80 DIN 1480 springed Ac 1 eared screw M8 x 16 DIN 316 Ac8.8 GT 1 eared screw M10 x 20 DIN 316 Ac 8.8 GT 2 eared screws M10 x 40 DIN316 Ac 8.8 GT 4 screws hexagonal M8 x 30 Ac 8.8 DIN 933 1 hexagonal screwsM8 x 16 Ac 8.8 DIN 933 1 hexagonal screws M10 x 25 Ac 8.8 DIN 933 12hexagonal screws M10 x 30 Ac 8.8 DIN 933 3 hexagonal screws M10 x 40 Ac 8.8DIN 933 2 hexagonal screws M10 x 60 Ac 8.8 DIN 933 3 hexagonal screws M12 x50 Ac 8.8 DIN 934 6 hexagonal screws M16 x 70 Ac 8.8 DIN 933 8 hexagonal nutM6 Ac 4.6 DIN 934 4 hexagonal nut M8 Ac 4.6 DIN 934 M16 hexagonal nut 6 Ac4.6 DIN 934 8 screws with hollow head M6 x 40 Ac A 8.8 DIN 963 2 kit clampingmanchon 2 bearings with protected housing 2 sieves steel 2 joint leather

See section 3.7 for further information regarding the 4 last pieces above.

We note that the two lists above (paragraphs 3.1.1 and 3.1.2) oly include theconstruction parts of the huller. They thus not include neither the tools nor themanufacturing parts.

In addition, the workshop that wishes to produce this model of huller must haveat least the following material: - A lathe; - A milling machine or joiner's bench; -A sheet cutter; - A welding post; - A drill.

Identification of the different sets

Rep. Qty. Number Name Material Standard 1 1 01-000 assembly support 2 1 02-000 assembly of lowerbody 3 1 03-000 assembly rotor 4 1 04-000 assemblyupper body 5 2 00-001 hinge steel St 37 6 2hexagonal screws M10 x 60 Ac 8.8 DIN 933 7 6hexagonal screws M16 x 70 Ac 8.8 DIN 933 8 6washers M16 steel DIN 125 A 9 6 hexagonal nutsM16 steel DIN 934 Note: See the tables withstandards of the metals in Annex 3.

The huller can be broken down into four sub-assemblies (respectively the support, the lowerbody, the rotor and the upper body) where each canbe separatly mounted and then later assembled toone another. We describe the four sub-assemblies inthe following paragraphs in detail.

Support

Rep. Qty. Number Name Material Standard 1 2 01-001 rear foot angle steel St 37 2 1 01-002 left frontfoot angle steel St 37 3 1 01-003 right front foot

12/02/13 Rice husker construction manual - Appropedia: The sustainability wiki

www.appropedia.org/Rice_husker_construction_manual 8/17

Support assembly

Lower body assembly

angle steel St 37 4 2 01-004 reinforcement sheetsteel St 37 5 2 01-005 flat plate body support steelSt 37 6 4 01-006 flat fixation plate ground steel St37 7 1 01-006 left spar angle steel St 37 8 1 01-008right spar angle steel St 37 9 1 01-009 front sheetsteel St 37 10 1 01-010 rear sheet steel St 37 11 201-011 crossed angle steel St 37

Note: See the table of standards for the metals inAppendix 3.

The support serves to assure the maintenance of thehuller at a height which is acceptable to the userand to fix the machine to the ground to avoid all awkward movements. Thesupport, manufactured by AECP, is created only mechanically welded. Itscreation poses no particular problem to any welder with a minimum ofexperience.

We note however that the support was a piece made in a foundry with mostolder models manufactured in series. The workshops that have a foundry couldperhaps be interested in using this method ... The two drilled holes in the upperpart (upper fixation body) must be made after welding the assembly together toensure correct tolerance of the distance.

The assembly plans and details of the support and its constructional componentsare found in Appendix 1, drawings 01-000 et seq.

The lower body

Rep. Qty. Number Name Material Standard 1 1 02-001 lower body cast iron FGL 250 2 2 02-002 closureclamp cast iron FGL 250 3 1 02-003 huller knifespringed Ac 51Si7 4 2 02-004 knife support cast ironFGL 250 5 2 02-005 adjustment screw for knife steelCk45 6 3 02-006 sieve clamping support cast ironFGL 250 7 3 02-007 sieve support cast iron FGL 2508 2 02-008 sieve steel 9 2 02-009 maintenance barof sieve steel 10 2 joint-axis body felt 11 3hexagonal screws M12 x 50 Ac 8.8 DIN 934 12 2eared screws M10 x 40 DIN 316 Ac 8.8 GT 13 4ankles dia. 10x80 DIN 1480 springed Ac 14 8 screwwith bored head M6 x 40 Ac A 8.8 DIN 963 15 8washers M6 Ac DIN 125 A 16 8 hexagonal nuts M6 Ac 4.6 DIN 934 17 12 washersM10 Ac 4.6 DIN 125 A 18 12 hexagonal screws M10 x 30 Ac 8.8 DIN 933

Note: See the table of the standards of the metals in Appendix 3.

The "lower body" assembly serves to support the rotor. It also has the functionof ensuring the fixation of the sieve, allowing the separation of the grain andmixing chaff and bran.

The drawings of the assembly and the mounting of the assembly of the lower

12/02/13 Rice husker construction manual - Appropedia: The sustainability wiki

www.appropedia.org/Rice_husker_construction_manual 9/17

body are found in Appendix 1, drawings 02-000.

The lower body

(Rep.1, see Appendix 1, drawing 02-001). This part is the basis of the huller asmost other pieces are connect to it. It is molded in cast iron and has noparticular mechanical features. The raw part must undergo several modifications:a milling of the upper surface to ensure a certain tightness with the upper body.Several holes are then made on drilling templates. The detailed drawings ofthese templates can be found in Appendix 2, drawings A1-000 and A2-000.

The clamp closure

(Rep.2, see Appendix 1, drawing 02-002) This piece should be created in castiron or in a material with a comparable or inferior durability: the clamp isactually designed to break in case of inoparability or abrupt blocking of themachine, thus avoiding damage to the essential parts of the huller. The drillingof the two holes are done by means of a template.

The knife of the huller

(Rep.3, see Appendix 1, drawing 02-003) This piece, in combination with thehulling cylinders, allow the separating of the chaffs and brans of the rice. Theknife of the huller must be replaced regularly, because it comes in in contactwith the chaff of rice which is very abrasive. To limit the wear nevertheless, theknife is made in steel à ressorts with increased durability (see characteristics inAppendix 3). For this reason, we must be very careful during the milling, asadvancing too quickly can cause the tools to break.

The knife support

(Rep.4, see Appendix 1, drawing 02-004) This part provides the link between theknife and adjustment screw. One could imagine of removing this part by puttingthe knife directly in contact with the adjustment screw. But the knife supportprovides an important feature: like the clamp closure, it is a rupture part. In theevent of a severe impact in the mechanism, the support brakes, which permitsthe release of the knife, and avoids in most cases to breaking of parts that aremore difficult or expensive to replace. This part is therefore made in cast iron ora material which is comparable or inferior in durability.

The adjustment screw for the knife

(Rep.5, see Appendix 1, drawing 02-005) At both ends of the knife is a screw toallow the adjustment of the distance between the knife and the hulling cylinders(this distance should be slightly higher than the diameter of hulled rice, butlower than that of the paddy rice). We must try to keep the knife parallel to therotor axis, so that it works evenly over its entire length.

The tightening of the sieve support

12/02/13 Rice husker construction manual - Appropedia: The sustainability wiki

www.appropedia.org/Rice_husker_construction_manual 10/17

lower body

closure clamp

hulling knife

support for the knife

(Rep.6, see Appendix 1, drawing 02-006) This part holds the thightening screwthat allows the tightening of the sieve.

It is molded in cast iron and has no particularmechanical features. On the contrary, in case ofexcessive stress, it must break as well in order toprotect other parts. The raw part is drilled on atemplate, after which the holes are tapped.

The sieve support

(Rep.7, see Appendix 1, drawing 02-007) The sievesupport has as function to secure the sieve, and tostick it against the maintenance bars which assureits fixation to the other side. Its curvature alsoallows the sieve to retain its cylindrical shape.

It is molded in cast iron and has no particularmechanical features.

The sieve

(Rep.8, see Appendix 1, Plan 02-008) The screen is agrid whose holes are big enough to allow the chaffand bran to cross, but also small enough to notallow the hulled rice to cross the grid.

It is strongly advised to subcontract this piece. Itsmanufacturing is not overly difficult, but requires toomuch time for insufficiently equipped workshops. Asupplier is proposed (see page 24). Beginning with aflat piece, we still need to give it an adequateradius of curvature.

The maintenance bar for the sieve

(Rep.9, see Appendix 1, drawing 02-009) Themaintenance bar has a notch in which the bord ofthe sieve fits into. The sieve support holds the sievein this notch so that it can not escape.

This piece should be made of hardened steel as it issubjected to strong wear through scouring.

The two main sides of this piece are milled on anangle of 5 degrees. In order to have have sufficientprecision with this angle, the piece is milled on atemplate. When the first side is milled, we turn thepiece and mill the other side. The detailed drawingof this template can be found in Appendix 2, drawing A4-000.

12/02/13 Rice husker construction manual - Appropedia: The sustainability wiki

www.appropedia.org/Rice_husker_construction_manual 11/17

adjustment screw for the

knife

Sieve support clamp

Sieve support

Sieve

The rotor

Rep.Qty.Nr. Designation Material Standard 1 1 03-001 axis Ø 2" h7 steel Ck45h72 1 03-002 primary hulling cylinder white cast iron 31 03-003 secondary hulling cylinder white cast iron 41 03-004 pulley drivetrain cast iron FGL 250 5 1 03-005 nut primary cylinder cast iron FGL 250 6 1 03-006 nut secondary cylinder cast iron FGL 250 7 1hexagonal screws M10 x 40 Ac 8.8 DIN 934 8 2 03-007 seal (waterproof leather washer) leather 9 1 03-008 end key DIN 6885-A 12x8x120 steel Ck45 10 103-009 central key DIN6885-A 12x8x56 steel Ck4511 2 bearing en fonte a semelle 12 2 kit thighteningmanchon

Note: See the table of standards of the metals inAppendix 3.

The axis

(Rep.1, see Appendix 1, drawing 03-001) The axisensures the maintenance of the various movingparts in the huller. It also ensures the pulleytransmission to the working parts. We create it byturning a round sheet 2. Three junctions of cottersare then milled.

The primary hulling cylinder

(Rep.2, see Appendix 1, drawing 03-002) Thiscylinder has two functional parts:

the part that lies below the hopper has obliqueelevations which act like a neverending screwthat guide the paddy rice to the exit;the part that lies at the center of the body hasparallel elevations on the axis that perform thesame function as the knife. One could almostsay they are "rotating knives."

This piece must be very durable. It must have astrong resistance against wear and scouring. Thenon-hulled rice is indeed very abrasive and cylinderswear fairly quickly. As such, it is molded in whitecast iron, ie to obtain a significant hardness fromthe creation of a piece cooled in ordinary cast iron(which is gray cast iron, see the standards inAppendix 3), we must ensure a rapid cooling of thecast iron in the mold. Therefore, it we cool it, not ina sand mold but in a steel mold or by casting. We then talk of cooling in a metalshell, which requires a bit of little specific know-how. The rapid cooling of molten

12/02/13 Rice husker construction manual - Appropedia: The sustainability wiki

www.appropedia.org/Rice_husker_construction_manual 12/17

Maintenance bar of the

sieve

Assembly of the rotor

Axis

iron acts acts as a quenching. The hardness of the finished piece is about 30HRC (or 96kg/mm ²). The difficulty with this method lies with the creation of theof the shells. For this part, the molds were created through a regular cast (whitecast iron, see the standards in Appendix 3). We hadto cut the the mold in 3 sections of 120 degrees andmodify the outer side to allow their insertion in thesand model. Codéart can help you for the realisationof this piece, or even give you one.

A junction of cotters must then be modified in thecylinder profile of the hulling cylinder. As this piecehas a great hardiness , we must keep in mind that itis very difficult to modify. Be careful to not break thetools!

The secondary hulling cylinder

(Rep.3, see Appendix 1, drawing 03-003) Thiscylinder has two functional parts such as the primarycylinder:

the part which is located opposite the to theexit and designed to facilitate the exiting of therice;the part that lies in the center of the body alsoincludes elevations parallel to the axis that actas a knife and ensure the hulling.

This part is also molded in white cast iron and musthave a great durability, in order to resist wear, seethe pragraph above.

One could ask himself the question why the twocylinders have not been assembled into a singlecylinder. Firstly, because a single cylinder would bemuch more difficult to cast. Also, the prmary cylinderwears much faster than secondary one. Savings arethus possible on these parts by not replacing more than one part at a time.Nevertheless, the AECP in collaboration with Codéart, are momentarily carryingout the testing of a version with a single cylinder, cast in fused iron (white castiron and chromium, see characteristics in Appendix 3), which would allow theavoiding of the two drawbacks cited above.

The pulley drivetrain

(Rep.4, see Appendix 1, drawing 03-004) It is through the pulley that the belttransmits power to the engine of the axis. The mass and inertia of the pulley aredeliberately hightened: when the engine used is a single cylinder diesel engine,the non-negligable inertia of the pulley allows to control a movement that wouldotherwise be subject to abrupt movements. The pulley is mounted on the axis bymeans of a conical manchet.

12/02/13 Rice husker construction manual - Appropedia: The sustainability wiki

www.appropedia.org/Rice_husker_construction_manual 13/17

primary hulling cylinder

secondary hulling cylinder

This piece is molded in cast iron and has nopartcular mechanical features. The central hole isconical and must be created on a lathe. The twogorges of belts are equally turned.

The attaching of the pulley

The attachment of the pulley is done by cylindricalmounting and adjusted clamping, or more precisily,the mounting is done by means of a tighteningscrew, oblique put, to secure the key (see Figure 25and drawing 03-004).The oblique placing of thescrew is imposed by the configuration of the pulleywhich not allows to drill a hole perpendicular to theaxis (this should be corrected in a later version ofthe pulley and its foundry mold). Although thissolution may seem rudimentary, it is neverthelessquite satisfactory. Moreover, it eliminates the needto place an extra part, or a attachment platform, aconical clamp, or part that is difficult to make or findlocally.

The nuts of the primary and secondary dehusking cylinders

(Rep.5 & 6, see Appendix 1, drawings 03-005 & 03-006) These two pieces areidentical, except for the net, which is left for the nut of the primary cylinder andright for the secondary cylinder.

These parts are cast in cast iron and have no particular mechanicalcharacteristics.

The bearings

The bearings are standard tightening bearings by conical clamp. The bearingsused by AECP are bearings of the NTN brand type UKP-209, but other brandsalso supply bearings similar in all respects; an example are the SKF type SY-509M bearings. We choose the type of press-plate by focusing on those made ofcast iron as they include an oiler. For further information, see page 24.

The upper body

Rep. Qty. Number Name Material Standard 1 1 04-001 supply hopper steel St 372 1 04-002 upper body cast iron FGL 250 3 1 04-003 supply mouth feeding grayFGL 250 4 1 04-004 exit mouth cast iron FGL 250 5 1 04-005 exit sheet forinspection steel St 37 6 1 04-006 closure sheet for exit steel St 37 7 1 04-007closure sheet steel food St 37 8 2-axis joint body felt 9 4 hexagonal screws M8 x30 Ac 8.8 DIN 933 10 4 washer M8 Ac 8.8 DIN 125A 11 4 hexagonal nut M8 Ac4.6 DIN 934 12 1 hexagonal screws M8 x 16 Ac 8.8 DIN 933 13 1 ears screws M8x 16 DIN 316 Ac 8.8 GT 14 1 ear screws M10 x 20 DIN 316 Ac 8.8 GT 15 3 washerM10 Ac 4.6 DIN 125A 16 1 hexagonal screws M10 x 25 Ac 8.8 DIN 933 17 2

12/02/13 Rice husker construction manual - Appropedia: The sustainability wiki

www.appropedia.org/Rice_husker_construction_manual 14/17

Drivetrain pulley

File:Rice huskerconstruction manualISFIAI image 25.png

Attaching of the pulley

by an obliquely placed

screw

Nut used in the cylinders

hexagonal screws M10 x 40 Ac 8.8 DIN 933 Note: See the table with standardsfor the metals in Appendix 3.

The upper body is a kind of lid that can open the machine without the need ofdisassembling it. This assembly also includes feeding systems and releasesystems for the rice.

The supply hopper

(Rep.1, see Appendix 1, drawings 04-001) It's in the hopper that we put thenon-hulled rice. It allows to load a large quantity of rice in a single drop,avoiding the user to having to load the hoppercontinuously. This procedure also avoids thephenomenon of uprising due to the rotation of thescrew.

The hopper is mechanically welded.

The upper body

(Rep.2, see Appendix 1, drawing 04-002) This pieceis the "lid" of the sheller. It also permits to providemaintaintenance to the feeding and release devices.This piece is molded in cast iron and has noparticular mechanical features.

The raw part must undergo several modifications:Milling of the lower surface to ensure a certainsealing with the lower body. Several holes are drilledon a template. The detailed drawings of this templatecan be found in Appendix 2, drawing A3-000.

The supply mouth

(Rep.3, see Appendix 1, drawing 04-003) This pieceserves as a support for the hopper. It also permitsto control the input flow via the closing feedingsheet (Rep.7 see Appendix 1, drawing 04-007). Thispiece is molded in cast iron and should has noparticular mechanical feature.

The bottom surface is milled to ensure a propercontact with the body of huller. The different fixationholes are made by the drill on template. One ofthese holes must also be tapped.

The exit mouth

(Rep.4, see Appendix 1, drawing 04-004) This pieceis designed to ensure ideal release conditions forthe hulled rice. The relative high position of this

12/02/13 Rice husker construction manual - Appropedia: The sustainability wiki

www.appropedia.org/Rice_husker_construction_manual 15/17

Bearings

Assembly of the upper

body

Supply hopper

Upper body

piece in relation to the cylinder allows to separatethe rice mixture of the chaff and sound, since onlythe heavier grain, are dragged up to that height.

This component also supports two adjustmentpieces for the exit: the control sheets (Rep.5, seeAppendix 1, Plan 04-005) and the closing sheets forthe exit (Rep.6 see Appendix 1, drawing 04-006).

Several holes are made with the drill on template.Detailed drawings of this template are found inAppendix 2, drawing A5-000.

Parts to buy

Some parts are not feasible to create for a workshop(or their production cost would be too expensive), aswe have previously stated. Therefore, we offer belowthe details of suppliers and the references of thepieces, within the limits of the currently availableinformation at the time ofwriting. You can alsocontact the Belgian A.S.B.L. Codéart (see details onpage 5).

Sieve Drawing: No. 02-008 Features: 1.5 x 228 mm x215 Abwicklung Material: Steel St 12-03 Supplier:Pope & Heidersdorf Gmbh & Co Angerburg Strasse 2122,047 Hamburg - Wandsbek Germany Tel: +49 40694 49 50 Fax: +49 40 695 01 40 Quantity perhuller: 1 Unit price: 12 euros ~

Joint Drawing: No. 03-007 Description: Washer ofwaterproof leather Features: dia. 138 x 39 x 4 mmSupplier: Fouilleul S.A. 50 rue du Gué-d'Orger 53 000Laval France Tel: +33 2 43 02 96 00 Fax: +33 2 4302 85 92 Quantity per huller: 2 Unit price: ~ 2.90euros

Bearings Description: bearing en fonte à semelleserrage by manchet Features: NTN UKP209 Quantityper huller: 2

Kit thightening manchon Description: kit thighteningmanchet for the bearing UKP209 Features: NTNH2309X Quantity per huller: 2

Drivetrain

The sheller can be powered either by an electric motor, or by a diesel engine.The power required is almost 15CV or 11kW. The transmission is made by V-belt,the diameter of the driving pulley is chosen so as to have a rotor speed between600 and 800 rpm.

12/02/13 Rice husker construction manual - Appropedia: The sustainability wiki

www.appropedia.org/Rice_husker_construction_manual 16/17

Supply mouth

Exit mouth

Coupling if the engine used

has only little radial

resistance

The engine is used at AECP is a Hatz engine (http://www.hatz.com). This dieselengine is often used on agri-food machines and rural areas. Like many others, itis not designed to withstand a radial tension on its axis, other than the tensionof the belt induces a radial load on the pulley. With this type of engine, thepulley can not be mounted directly on the engine axis. We thus use for this casea coupling attached to the two intermediatebearings and support the driving pulley. Thisassembly is connected to the engine by a flexiblecoupling to correct a margin of misalignment.

In areas where this is possible, we could also useelectric engines. These requires no specialmaintenance.

The production of the templates

The drawings of most templates used in Camp Perrinfor the drilling of the parts are grouped in Apendix 2.These templates can be modified without anyproblem using the available materials in theworkshop at the time of their manufacturing. Only afew dimensions for constructions (mostly theplacement of the drilling guns) must be respected.Of the drawings presented here, the tightening ofthe clames is done by standard hexagonal screws.We can improve this system by tightening theclames through eccentric screws (see Figure 34).This device allows a faster assembly anddisassembly of the workpieces.

We could of course also consider building the hullerswithout the use of these templates, by measuringand counter-piercing the assembly, since most of thedrillings do not require a very high accuracy.However, the drilling is done much more quicklyusing the templates. In addition, another favorableargument is that through the templates, all partsare identical, which allows you to standardize theparts and facilitate maintenance.

Maintenance

The only regular maintenance that the hullerrequires is the lubrication of the bearings. Cleaningthe inside of the machine is also recommended. Ideally, worn parts must bereplaced as soon as the performance of the machine starts to fall due to theiraging. These parts are mainly the knife, the primary hulling cylinder and to alesser extent, the secondary hulling cylinder. We estimate that the first twoelements listed must be replaced after a production of about 300 tonnes ofhusked rice. The sieve and the fixation bars (with the adapted settings of thescrews) will also need to be replaced from time to time.

12/02/13 Rice husker construction manual - Appropedia: The sustainability wiki

www.appropedia.org/Rice_husker_construction_manual 17/17

Template with eccentric

clamping

The engine, whether electric or thermal, should be objected to regularmaintenance of the type that is usual for such machines. The engine should notsuffer from failures if it is properly used and maintained. Nevertheless, we mustbe careful to keep the facility from being suspended because of the engine(most frequent case). It is thus desirable to get enough spare parts in advance,at least sufficient to allow a rapid fixing of the engine by a local manufacturer(the common parts of a diesel engine are segments,pistons, crankshafts, rods, injectors, pumps ...)Regarding electrical engines, there is no specialmaintenance except for the periodic cleaning of thecooling fins. Also check up on the magnetic-thermalcircuit breaker.

Bibliography

(1) Angladette A., Le riz, coll. Que sais-je?,Presses Universitaires de France, Paris,

1967, 126pp.

(2) Cruz J.F. et Souare D., Transformation du rizen Guinée, CIRAD, Montpellier,

France, 1997, 37pp.

(3) Juliano B.O., Le riz dans la nutritionhumaine, FA0, Rome, 1994, 184pp.

Appendixes

6.1. Appendix 1: Drawings of the parts 6.2. Appendix 2: Drawings of the tools6.3. Appendix 3: Table of the standards of the metals 6.4. Appendix 4: Table ofthe nutritional information of paddy rice and diagram of a rice grain 6.5.Appendix 5: Discontinued hullers

References

1. ↑ Original document (http://www.isf-iai.be/fileadmin/user_upload/manuels/manuel_decortiqueur_web.pdf)

Retrieved from "http://www.appropedia.org/Rice_husker_construction_manual"Categories: ISF-IAI documents | Agricultural tools manuals | Agriculturalprocessing tools manuals | Haiti

[1 watching user]Page was last modified 07:45, 10 February 2013. Based on work by ChrisWatkins, Chriswaterguy's bot, KVDP and Lonny Grafman and Appropediaanonymous user 70.135.114.247.

Text is available under CC-by-sa