ICS 65.060.01  
 
Reference number  
DRS  269-1:2020  
© RSB 2020  
  
 RWANDA 
STANDARD  DRS  
269-1:2020  
 
2nd edition  
2020 -June  
 
Agroprocessing  machine — Test methods 
—  
 
Part 1: Rice thresher  
   
DRS  269-1:2020  
©RSB 2020 - All rights reserved                  ii 
 In order to match with technological development and to keep continuous progress in industries, 
standards are subject to periodic review. Users shall ascertain that they are in possession of the latest 
edition  
 
 
 
 
 
 
 
 
© RSB2020  
All rights reserved. Unless  otherwise specified, no part of this publication may be reproduced or utilized 
in any form or by any means, electronic or mechanical, including photocopying and microfilm, without 
prior written permission from R SB. 
Requests for permission to reproduce thi s document should be addressed to : 
Rwanda Standards  Board  
P.O Box 7099 Kigali -Rwanda  
KK 15 Rd, 49  
Tel. +250 788303492  
Toll Free: 3250  
E-mail: info@rsb.gov.rw  
Website: www.rsb.gov.rw  
ePortal: www.portal.rsb.gov.rw  DRS  269-1:2020  
iii                ©RSB2020 - All rights reserved  
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ .............................  v 
1 Scope  ................................ ................................ ................................ ................................ ......................  1 
2 Normative references  ................................ ................................ ................................ ............................  1 
3 Terms and definitions  ................................ ................................ ................................ ...........................  1 
4 General conditions for test and inspection  ................................ ................................ ........................  2 
4.1 Role of manufacturer/dealer  ................................ ................................ ................................ .................  2 
4.2 Test site conditions  ................................ ................................ ................................ ...............................  2 
5 Suspensi on of test  ................................ ................................ ................................ ................................  2 
6 Test preparation  ................................ ................................ ................................ ................................ .... 3 
6.1 Running -in and preliminary adjustment  ................................ ................................ .............................  3 
6.2 Test materials  ................................ ................................ ................................ ................................ ........  3 
7 Pre-test observation  ................................ ................................ ................................ ..............................  3 
8 Performance test  ................................ ................................ ................................ ................................ ... 3 
8.1 Operation of  the thresher  ................................ ................................ ................................ .....................  3 
8.2 Sampling  ................................ ................................ ................................ ................................ ................  3 
8.3 Data collection  ................................ ................................ ................................ ................................ ....... 3 
8.3.1  Noise level  ................................ ................................ ................................ ................................ ..............  4 
8.3.2  Speed of components  ................................ ................................ ................................ ...........................  4 
8.3.3  Air velocity  ................................ ................................ ............................... Error! Bookmark not defined. 4 
8.3.4  Fuel consumption  ................................ ................................ ................................ ................................ .. 4 
8.3.5  Data recording and observations  ................................ ................................ ................................ ........  4 
9 Laboratory analysis  ................................ ................................ ................................ ...............................  4 
10 Data analysis  ................................ ................................ ................................ ................................ ..........  4 
10.1  Calculation  ................................ ................................ ................................ ................................ .............  4 
10.2  Presentation of results ................................ ................................ ................................ ..........................  4 
11 Test report  ................................ ................................ ................................ ................................ ............  45 
Annex  A (normative)  Test materials for mechanical rice thresher  ................................ ..............................  6 
A.1 Sample characteristics  ................................ ................................ ................................ .........................  6 
A.2 Quantity to be supplied ................................ ................................ ................................ .........................  6 
A.3 Sample preparation  ................................ ................................ ................................ ...............................  6 
Annex  B (normative)  Specification for mechanical rice  ................................ ................................ ................  7 
Annex  C (normative)  Sampling and measurements for test material  ................................ ........................  13 
C.1 Sampling from different outlets  ................................ ................................ ................................ .........  13 
C.2 Collection of scattered grains  ................................ ................................ ................................ ............  14 
C.3 Handling of samples  ................................ ................................ ................................ ...........................  14 
C.4 Other measurements required during the test run  ................................ ................................ ..........  14 
C.5 Measurement of fuel consumption  ................................ ................................ ................................ .... 15 
Annex  D (normative)  Field performance test data sheet  ................................ ................................ .............  16 DRS  269-1:2020  
©RSB 2020 - All rights reserved                  iv 
 Annex  E (normative)  Laboratory work ................................ ................................ ................................ ..........  20 
E.1 Measurement of straw length  ................................ ................................ ................................ ............  20 
E.2 Measurement of grain content  ................................ ................................ ................................ ..........  20 
E.3 Purity determination  ................................ ................................ ................................ ...........................  20 
E.4 Determination of losses  ................................ ................................ ................................ .....................  20 
E.4.1  Blower loss  ................................ ................................ ................................ ................................ ..........  20 
E.4.2  Separation  loss ................................ ................................ ................................ ................................ ... 21 
E.4.3  Unthreshed loss  ................................ ................................ ................................ ................................ .. 21 
E.4.4  Scattering loss  ................................ ................................ ................................ ................................ .... 21 
E.5 Determination of net percent cracked grains  ................................ ................................ ..................  21 
E.6 Determination of percent mechanically -damaged grains ................................ ...............................  21 
Annex  F (normative)  Laboratory grain analysis data sheet  ................................ ................................ ....... 22 
F.1 Crop conditions  ................................ ................................ ................................ ................................ .........  22 
F.2 Kernel analysis  ................................ ................................ ................................ ................................ ..........  23 
Annex  G (normative)  Formula used during calculations and testing  ................................ .......................  25 
 DRS  269-1:2020  
v                ©RSB2020 - All rights reserved  
 Foreword  
Rwanda Standard s are prepared  by Technical Committees and approved by R wanda Standards Board (RSB) 
Board  of Directors in  accordance with the procedures of RSB, in compliance with Annex 3 of the WTO/TBT 
agreement on the preparation, adoption and application of standards.  
The main task of technical committees is to prepare national standards.  Final Draft Rwanda S tandards 
adopted by Technical committ ees are ratified  by me mbers of RSB Board of Director s for publication and 
gazettment as Rwanda Standards.  
DRS  265-1 was prepared by Technical Committee RSB/TC 47, Steel, aluminium and related products.  
In the preparation of this standard, reference was made to the following standard  (s): 
1) XYZ: Title  
2) XYZ:Title  
The assistance de rived from the above source is hereby acknowledged with thanks.  
This second  edition cancels and replaces the first  edition (RS  269-1:2015 ) of which has been technically 
revised.  
DRS  269 consists of the following parts, under the general title Agroprocessing  machinery — Test methods : 
 Part 1: Price thresher  
 Part 2: Power operated maize sheller  
Part 3: Rice mill  
 Part 4: Heated air mechanical grain dryer  
 Part 5: Maize mill  
Committee membership  
The following organizations were represented on the Technical Committee on Steel, aluminium and related 
products (RSB/TC 47 ) in the preparation of this standard.  
University of Rwanda/ college of science and technology  
University of Rwanda/College of agriculture animal science and veterinary medicine  DRS  269-1:2020  
©RSB 2020 - All rights reserved                  vi 
 Kabizu business group  
Rwanda Polytechnic/IPRC Kigali  
Rwanda Polytechnic/IPRC Ngoma  
Rwanda Polytechnic/IPRC Musanze  
RWANTECH Boilers  
Rwanda Inspectorate and competition authority  
Rwanda Institute for Conservation Agriculture  
ACER Ltd  
Rwanda  Standards Board (RSB) – Secretariat   DRS  269-1:2020  
vii                ©RSB2020 - All rights reserved  
  DRS  269-1:2020  
1                ©RSB2020 - All rights reserved  
 Agroprocessing  machinery — Test methods — Part 1: Rice thresher  
1 Scope  
This draft Rwanda Standard specifies the methods of sampling, testing an d inspection for rice thresher.  
2 Normative references  
The following documents are referred to in the text in such a way that some or all of  their content constitutes 
requirements of this document.  For dated references, only the editioncited applies. For undated references, 
the latest edition of the referenced  document (including any amendments) applies.  
DRS 268 -1, Agroprocessing machines  — Specification — Part 1: Rice thresher  
RS 241 , Agricultural machinery — Methods of sampling.  
3 Terms and definitions  
For the purposes of this document, the terms and definition s given in  RS 268 -1 apply.  
ISO and IEC maintain terminological databases for use in standardization at the following addresses:  
— IEC Electropedia: available at http://www.electropedia.org/  
— ISO Online browsing  platform: available at http://www.iso.org/obp  
3.1 
actual capacity  
weight of the threshed grain collected from the main grain outlet per unit time  
3.2 
clean threshed grain  
threshed  grain with 100% purity exclusive of the em pty grains and other impurities  
3.3 
concave clearance  
clearance between cylinder threshing  elements and concave component   
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 3.4 
concave component  
iron grill frame partly surrounding the cylinder on which the threshi ng elements rubs, shear  and/or impact the 
cut plants  
3.5 
corrected capacity  
corrected capacity of the thresher at 20 % grain moisture content (wet basis), grain -straw r atio of 0.55 % and 
100 % purity  
3.6 
cylinder peripheral speed  
equivalent  linear speed of the cylinder tip when running at normal op erating speed, expressed in m/s  
3.7 
threshing output  
weight of the threshed grain s collected at the grain outlet  
3.8 
total grain input  
sum of the weights of collected threshed grains and all thresh ing losses.  
4 General conditions for test and inspection  
4.1 Role of manufacturer/dealer  
The manufacturer/dealer shall comply with the test procedures of national testing authority.  
4.2 Test site conditions  
The thresher shall be installed on a stable level ground o n a site with sufficient working space, and shall be 
positioned in such a way that the wind will not blow the straws and other impurities into the clean grain.  
5 Suspension of test  
5.1 If during the test run, the machine stops due to major component breakdo wn or malfunction so as to 
affect the machine’s performance, the test may be suspended.   DRS  269-1:2020  
3                ©RSB2020 - All rights reserved  
 5.2 The decision to suspend or to continue the test is at the discretion of the test engineer and concurred by 
the manufacturer’s representative.  
6 Test preparation  
6.1 Running -in and preliminary adjustment  
6.1.1  Before the start of the test, the thresher should have undergone a break -in period.   
5.1.2  During the running -in period, the various adjustments of the thresher shall be made according to the 
manufacturer’s recommendations.  
6.2 Test materials  
The harvested crop to be used in the test shall be prepared in sufficient quantity using the procedure given in 
Annex A.  
7 Pre-test observation  
The specifications claimed by the manufacturer and the physical det ails given in Annex B shall be verified by 
the recognized testing authority.  
8 Performance test  
8.1 Operation of the thresher  
8.1.1  The thresher shall be operated at the recommended speed and feed rate of the manufacturer.  
8.1.2  The same feeding rate recommended by the manufacturer shall be maintained during the test run.  
8.1.3  After the test run, the threshing area shall be cleaned and then prepared for the next trial.  
8.1.4  This procedure shall be repeated for at least three t est trials with duration of at least 15 min per trial, 
shall be adopted  
8.2 Sampling  
Sampling procedure is given in Annex C.  
8.3 Data collection  
8.3.1  Duration of test  
The duration of each test trial shall start with the feeding of the first harvested crop and ends after the feeding 
of the last batch. All discharge from the different outlets shall be included after the time cut off.   
©RSB 2020 - All rights reserved                  4 
 8.3.1  Noise level  
8.3.2.1  The noise emitted by the machine, with or without load, shall be measured using a noise level 
meter both at th e location of the operators and baggers.   
8.3.2.2  The noise limit, expressed in db (A), shall be taken according to RS 236  
8.3.2  Speed of components  
The speed of the threshing cylinder, blower, and other driven components, with and without load, shall be 
measu red using a tachometer, expressed in rpm.  
8.3.3  Fuel consumption  
Before the start of each test trial, fuel tank shall be filled to its capacity and after each test; the fuel consumed 
in L/h shall be measured by refilling the tank to the same level.  
8.3.4  Data recording and observations  
Record sheet for all data, information during the test, and other observations is given in Annex D.  
9 Laboratory analysis  
The laboratory procedures to be followed in the analysis are given in Annex E while the data sheet is given in 
Annex F.  
10 Data analysis  
10.1 Calculation  
10.1.1  For uniform result of output capacity due to variation in grain moisture content and grain ratio, the 
output capacity shall be corrected at 100 % purity, 14 % moisture content, and 0.55 grain -straw ratio.   
10.1.2 The formula to be used in the calculation of different test parameters are given in Annex G.  
10.2 Presentation of results  
Machine specifications and the results of the test shall be presented in tabular form using the data from 
Annexes B and D.   
11 Test repo rt 
The test report shall inc lude the following information:  
a) title;  DRS  269-1:2020  
5                ©RSB2020 - All rights reserved  
 b) summary of results;   
c) purpose and scope of Test;   
d) methods of Test;   
e) conditions of the machine;   
f) results of test;   
g) observations (include pictures); and  
h) names an d signatures of test engineers   
©RSB 2020 - All rights reserved                  6 
 Annex  A 
(normative)  
 
Test materials for mechanical rice thresher  
A.1 Sample characteristics  
Test materials to be used shall have the following characteristics:  
a) variety : commonly grown locally;  
b) grain moisture content : 14 % maximum, wet basis;  
c) straw length : 45 cm - 50 cm; and  
d) grain -straw ratio : 0.50 – 0.65  
A.2 Quantity to be supplied  
The amount of test material to be supplied shall be sufficient for three hours of continuous threshing operation 
in order to provide samples to be used for running -in prior to the actual conduct of test trials. Approximately: 1 
hour x threshing capacity (kg/h)  
A.3 Sample preparation  
Prepare the sample in such a way that test sample to be used for the running -in and in e ach test trial shall 
have identical characteristics in terms of moisture content, variety and date of harvest and cultural 
management, fertilizer input.  
  DRS  269-1:2020  
7                ©RSB2020 - All rights reserved  
 Annex  B 
(normative)  
 
Specification for mechanical rice  
Name of Applicant: __________________________________ _______________________  
Address: __________________________________________________________________  
Tel No: ___________________________________________________________________  
Distributor: ________________________________________________________________  
Address: __________________________________________________________________  
GENERAL INFORMATION  
Make: _________________________ Brand/Model: _______________________________  
Serial No: ______________________ Classification: _______________________________  
Production date of thresher to be tested: __________________________________________ (or Date of 
manufacture)  
Table 1 — Items to be inspected  
ITEMS Ma nufacturer’s  Manufacturer’s 
Specifications  Verification by the  
Testing Agency  
C.1 Dimension and weight of thresher    
C.1.1 Overall length (mm)    
C.1.2 Overall width (mm)    
C.1.3 Overall height (mm)    
C.1.4 Overall weight, without engine (kg)    
C.2 Rated capacity (kg/h) range    
C.3 Component speeds (without load)     
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 C.3.1 Cylinder    
C.3.1.1 Shaft speed (rpm)    
C.3.1.2 Peripheral speed (m/s)    
C.3.2 Fan or blower shaft (rpm)    
C.3.3 Oscillating screen shaft (rpm)    
C.3.4 Auger shaft (rpm)    
C.4 Engine    
C.4.1 Brand    
C.4.2 Model    
C.4.3 Serial Number    
C.4.4 Make    
C.4.5 Type (cycle and ignition)    
C.4.6 Rated speed (rpm)    
C.4.7 Rated power (kW)    
C.4.8 Weight (kg)    
C.4.9 Starting system    
C.5 Type of power transmission system    
C.5.1 ________ to __________    
C.5.2 ________ to __________    
C.5.3 ________ to __________    
C.5.4 ________ to __________    
C.5.5 Others (specify)    DRS  269-1:2020  
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 C.6 Type of clutch system    
C.7 Threshing chamber    
C.7.1 Cylinder    
C.7.1.1 Type    
C.7.1.2 Size, LxD (mm)    
C.7.1.3 Straw -thrower paddles    
C.7.1.3.1 Number    
C.7.1.3.2 Material    
C.7.1.3.3 Other features    
C.7.2 Cylinder teeth    
C.7.2.1 Type    
C.7.2.2 Size (mm)    
C.7.2.3 Number    
C.7.2.4 Distance between teeth (mm)    
C.7.2.5 Arrangement    
C.7.2.6 Material used    
C.7.2.7 Means of attachment    
C.7.2.8 Others    
C.7.3 Cylinder cover    
C.7.3.1 Shape    
C.7.3.2 Material    
C.7.3.3 Louver     
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 C.7.3.3.1 Number    
C.7.3.3.2 Inclination with respect the vertical axis (degrees)    
C.7.4 Concave    
C.7.4.1 Lower concave    
C.7.4.1.1 Material    
C.7.4.1.2 Spacing between grills    
C.7.4.1.3 Clearance between concave and cylinder teeth 
(mm)    
C.7.4.1.4 Stripper bars    
C.7.4.1.4.1 Number    
C.7.4.1.4.2 Location    
C7.4.1.4.3 Material    
C.7.4.2 Upper concave    
C.7.4.2.2 Material used    
C.7.4.2.3 Spacing between grills (mm)    
C8 Feeding Table    
C.8.1 Length (mm)    
C.8.2 Width (mm)    
C.8.3 Height from the ground (mm)    
C.8.4 Dimension of feeding port, L x W (mm)    
C.8.5 Mode of attachment    
C.8.6 Material    
C.9 Oscillating Screen/Sieve    DRS  269-1:2020  
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 C.9.1 Length (mm)    
C.9.2 Width (mm)    
C9.3 Size of perforations (mm)    
C.9.4 Length of stroke (mm)    
C.9.5 Angle of inclination (degrees)    
C.9.6 Material    
C.10 Blower/Aspirator    
C.10.1 Type    
C.10.2 Total Length    
C.10.3 Diameter    
C.10.4 Number of blades    
C.10.5 Size of inlet port (mm)    
C.10.6 Material    
C.10.7 Adjustment (if any)    
C.11 Auger    
C.11.1 Pitch (mm)    
C.11.2 Length (mm)    
C.11.3 Overall diameter (mm)    
C.11.4 Minimum clearance from housing    
C.11.5 Material    
C.12 Grain Chute     
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 C.12.1 Angle of inclination    
C.12.2 Material    
C.13 Transport device    
C.13.1 Type    
C.13.2 Size    
C.13.3 Adjustment (if any)    
C.14 Chassis    
C.14.1 Material    
C.15 Safety device(s), if any    
C.16 Minimum labour requirement    
C.17 Adjustment (s)    
C.18 Tools available with machine    
C.19 Other special features    
C.20 Illustration of Transmission System    
 
 
 
 
 
 
 
 DRS  269-1:2020  
13                ©RSB2020 - All rights reserved  
 Annex  C 
(normative)  
 
Sampling and measurements for test material  
C.1 Sampling from different outlets  
C.1.1  During each test trial, samples shall be collected from different outlets to be analyzed in the 
laboratory for losses, purity and grain quality.   
C.1.2  The minimum amount of sample to be taken shall be twice as much as what is needed for a 
particular anal ysis.   
C.1.3  The excess sample shall be used for reference purposes or for an eventual second check in case of 
review.   
C.1.4  The sampling procedures shall be undertaken at the following thresher outlets:  
a) main grain outlet:  
1) using a plastic bag or an appropriate container, collect four or more samples of 
approximately 0.5 kg each from the outlet; and  
2) a final sample of approximately 1.5 kg shall be taken to the laboratory for analysis.  
b) straw thrower outlet:   
1) in the collec tion of sample in this outlet, use a rectangular box -shaped nylon catch with a 
dimension of 1.5 m x 0.5 m open at one end of the small side;  
2) five samples shall be collected from this outlet with five -second duration per collection;  
3) separate the free grai n mixed with the straw and the grains that are still attached to the 
panicle; and  
4) put them in a separate container and label them as separation loss and unthreshed loss, 
respectively.  
c) chaff outlet:  
1) during the test, five samples shall be taken from th e chaff outlet for duration of about one 
minute per collection by using nylon net with a dimension of 1.5 m x 1.0 m held by two 
persons at both ends;   
©RSB 2020 - All rights reserved                  14 
 2) these samples shall be placed in appropriate containers and labelled as blower loss;  
3) if there is an outl et chute whose function is to collect and recycle the chaff materials, the 
amount of grains being recycled and the blower loss shall be taken separately;  
4) at the outlet chute a plastic bag or any appropriate container shall be used to collect three 
samples; and  
5) these samples shall be placed in appropriate containers and labelled as recycled sample.  
C.2 Collection of scattered grains  
C.2.1  For testing purposes,  scattered grains shall be gathered since these grains are part of the total grain 
input.   
C.2.2  Spread canvas sheets around the threshing floor area to catch these grains after each test trial. 
Place the collected grains in appropriate containers and lab el them as scattered grains.  
C.2.3  Provisions shall be provided for the collection scattered grains with maximum distance of 1.0 m away 
from the base of the machine.  
C.3 Handling of samples  
C.3.1  All samples to be taken to the laboratory shall be placed in a ppropriate containers and properly 
labelled.  
C.3.2  If the samples are not to be immediately analyzed, they should be air -dried and if necessary, treat 
the samples with chemicals such as insecticide in order to prevent the samples from possible damage.   
C.3.3 If the sample is to be used for determining moisture content, it shall be kept in dry and airtight 
containers.  
C.4 Other measurements required during the test run  
C.4.1  Data shall be taken for the following: speed of rotating components, air velocity, an d noise level at 
the location of the operators and baggers.   
C.4.2  For each data to be taken there shall be a minimum of five observations and these shall be taken 
without and with load.   
C.4.3  Before taking of data, it shall be ensured that the feed rat e, speed and other functional 
characteristics have stabilized.   
C.4.4  The time of sampling shall be properly spaced during the whole duration of the test trials.   
C.4.5  For air velocity, measurement shall be taken in at least six measuring points.  DRS  269-1:2020  
15                ©RSB2020 - All rights reserved  
 C.4.6  The test engineer shall decide on the location of the measuring points, which will provide him with a 
good estimate of the blower’s air velocity.  
C.5 Measurement of fuel consumption  
C.5.1  To get the amount of fuel consumed, the tank shall be filled to full c apacity before the test.   
C.5.2  After the test, fill the tank with measured fuel to the same level before the test.   
C.5.3  When filling up the tank, careful attention shall be paid to keep the tank horizontal and not to leave 
empty space in the tank.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
©RSB 2020 - All rights reserved                  16 
 Annex  D 
(normative)  
 
Field performance test data sheet  
Test Trial No: _______________________Date: ______________________________  
Test Engineers: _______________________Location: __________________________  
Test Specimen: _______________________  
 
Table 2 — Items to be inspected  
Items   Trial   
1  2  3  Average  
D.1 Crop Condition      
D.1.1 Variety      
D.1.2 Days after harvest      
D.1.3 Straw length (mm)      
D.1.4 Grain moisture content (%)      
D.1.5 Grain -straw ratio      
D.2 Performance test      
D.2.1 Speed of components (rpm)      
D.2.1.1 Prime mover      
D.2.1.1.1 Without load      
D.2.1.1.2 With load      
D.2.1.2 Threshing cylinder shaft      DRS  269-1:2020  
17                ©RSB2020 - All rights reserved  
 D.2.1.2.1 Without load      
D.2.1.2.2 With load      
D.2.1.3 Fan shaft      
D.2.1.3.1 Without load      
D.2.1.3.2 With load      
D.2.1.4 Oscillating screen shaft      
D.2.1.4.1 Without load      
D.2.1.4.2 With load      
D.2.1.5 Grain auger shaft      
D.2.1.5.1 Without load      
D.2.1.5.2 With load      
D.2.2 Fan air velocity (m/sec)      
D.2.2.1 Without load      
D.2.2.2 With load      
D.2.3 Noise level [db(A)]      
D.2.3.1 Feeder      
D.2.3.1.1 Without load      
D.2.3.1.2 With load      
D.2.3.2 Bagger      
D.2.3.2.1 Without load      
D.2.3.2.2 With load      
D.2.4 Operating time (min)       
©RSB 2020 - All rights reserved                  18 
 D.2.5 Threshed grains (kg)      
D.2.6 Threshing capacity (t/h)      
D.2.7 Fuel time (min)      
D.2.8 Fuel consumed (L)      
D.2.9 Fuel consumption (L/h)      
D.2.10 Observations:  
 
D.2.10.1 Ease of transporting the machine  
___________________________________________________________________________  
___________________________________________________________________________  
___________________________________________________________________________  
D.2.10.2 Adjustments such as belt tensions, clearance, air velocity and others  
___________________________________________________________________________  
______________________ _____________________________________________________  
___________________________________________________________________________  
D.2.10.3 Safety features  
___________________________________________________________________________  
_____________________ ______________________________________________________  
___________________________________________________________________________  
D.2.10.4 Presence of grains that are blown back at the feeding port during threshing operation  
___________________________ ________________________________________________  
___________________________________________________________________________  
___________________________________________________________________________  
D.2.10.5 Ease of cleaning the cylinder and concave  
___________________________________________________________________________  
___________________________________________________________________________  
___________________________________________________________________________  DRS  269-1:2020  
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 D.2.10.6 Ease of cleaning  the fan and housing assembly  
___________________________________________________________________________  
___________________________________________________________________________  
_______________________________________________________________________ ____  
D.2.10.7 Labor requirement  
___________________________________________________________________________ 
___________________________________________________________________________  
___________________________________________________________________________  
D.2.10.8 Failure or abnormalities that shall be observed on the thresher or its component  parts during and after the threshi ng 
operation.  
_______________________________________ ____________________________________  
___________________________________________________________________________  
___________________________________________________________________________  
D.2.10.9 Others  
_______________________________________________ ____________________________  
___________________________________________________________________________  
 
 
 
 
 
 
 
 
 
 
  
©RSB 2020 - All rights reserved                  20 
 Annex  E 
(normative)  
 
Laboratory work  
E.1 Measurement of straw length  
This shall be taken using at least ten representative samples of cut plants and measuring the length from the 
point of cut to the tip of the panicle.  
E.2 Measurement of grain content  
E.2.1  In measuring the grain -straw ratio, take three representative samples of approximately 500 g each of 
cut plants from the test materials.   
E.2.2  For each sample, manually thresh the grains from the panicle and determine the weight of the grain and 
the straw separately.   
E.2.3  Record and calculate the grain -straw ratio usin g the formula in Annex G.   
E.2.4  The average of the three samples shall be taken as the grain -straw ratio.  
E.3 Purity determination  
E.3.1  Take 500 g from the final sample taken from the main grain outlet and clean the grains to remove the 
impurities and oth er foreign matters.   
E.3.2 The clean grain shall be weighed and recorded.   
E.3.3 The percent purity is calculated using the formula in Annex G.  
E.4 Determination of losses  
E.4.1  Blower loss  
E.4.1.1 Five samples shall be taken at the chaff outlet to collect grains  mixed with the chaff.  
E.4.1.2 Each sample shall be cleaned and weighed.   
E.4.1.3  The total weight of the clean grains and the total time of collection shall be recorded for the 
computation of blower loss.   DRS  269-1:2020  
21                ©RSB2020 - All rights reserved  
 E.4.2  Separation loss  
E.4.2.1  Five samples shall be taken at the straw outlet to collect loose grains mixed with the straw.   
E.4.2.2  The total weight of the clean grains collected and the total time of collection of the five samples shall 
be taken and recorded for the computation of s eparation loss.   
E.4.3  Unthreshed loss  
E.4.3.1  Unthreshed grains collected at the straw outlet shall be hand threshed and weighed.  
E.4.3.2  The total weight and time of collection shall be taken and recorded for the computation of unthreshed 
loss.   
E.4.4  Scattering loss 
Grains scattered around the thresher with a maximum distance of 1.0 m away from the base of the machine, 
shall be collected after each trial, cleaned and weighed for the determination of scattering loss.  
E.5 Determination of net percent cracked grains  
E.5.1Three samples each from manually threshed and machine threshed grains shall be taken for analysis.   
E.5.2  Each sample shall consist of 100 grains.   
E.5.3 These grains shall be manually dehulled and inspected for the presence of fissures.   
E.5.4  The net percent cracked grains shall be taken as the difference between the values obtained from 
the manual and machine -threshed grain samples.  
E.6 Determination of percent mechanically -damaged grains  
E.6.1  Three samples from machine -threshed grains shall be taken for analysis.   
E.6.2  Each sample shall consist of 100 g.   
E.6.3 Separate those grains that were broken, crushed or dehulled (partially or fully) and weigh.   
E.6.4  Compute for the percentage of mechanically damaged grains  
 
 
  
©RSB 2020 - All rights reserved                  22 
 Annex  F 
(normative)  
 
Laborato ry grain analysis data sheet  
Machine Tested: _____________________ Analyzed by: _______________________  
Date of Test: ________________________ Date Analyzed: ______________________  
F.1 Crop conditions  
 
Table F 1 — Moisture content, (% w.b)  
Sample 
No.  Initial weight  Final weight  Moisture content%  
    
    
    
Average     
Table F 2 — Grain – Straw Ratio  
Sample 
No.  Weight of Grain and 
Straw (g)  Weight of Grain (g)  Grain -Straw Ratio  
1     
2     
3     
4     
5     
6     DRS  269-1:2020  
23                ©RSB2020 - All rights reserved  
 7     
8     
9     
10     
Average     
F.2 Kernel analysis  
Initial Weight of Samples (uncleaned) = 500 gms  
Table F 3 — Purity determination  
Items   Trail 1    Trail 2    Trail 3   Gen  
Avg 
1  2  3  Avg 1  2  3  Avg 1  2  3  Avg 
Cleaned (g)               
Purity (%)               
Table F 4 — Loss determination  
Trial No.  Blower  
Loss  Separation  
Loss  Unshelled  
Loss  Scattering  
Loss  
Duration:  Duration:  Duration:  Duration:  
Sample 
wt (g)  Total 
(Kg)  Sample wt  
(g)  Total 
(Kg)  Sample 
wt (g)  Total 
(Kg)  Sample 
wt (g)  Total 
(Kg)  
1  a          
b          
c          
Average          
2.  a           
©RSB 2020 - All rights reserved                  24 
 b          
c          
Average          
3.  a          
b          
c          
Average          
Gen. average          
Table F 5 — Threshing  efficiency/recovery determination  
Trial 
No.  Blower Loss  Separation  
Loss  Unshelled  
Loss  Scattering  
Loss  Total  
wt %  wt %  wt %  wt %  Output 
(kg)  Input 
(kg)  
1            
2            
3            
Average            
 
 
 
 
 
 
 DRS  269-1:2020  
25                ©RSB2020 - All rights reserved  
 Annex  G 
(normative)  
 
Formula used during calculations and testing  
 
 
©RSB 2020 - All rights reserved                  26 
  
 DRS  269-1:2020  
 
Price based on 25pages  
©RSB2020 - All right s reserved