ISO INTERNATIONAL STANDARD 8278 Second edition 2016-03-01 Aerospace series Hydraulic, pressure compensated, variable delivery pumps s General requirements Série aérospatiale-Pompes hydrauliques a debit variable régulé en fonction de la pressionExigences générales Reference number IS0 8278:2016(E) ISO International Organization for Standardization ZHEJIANG INSTOFSTANDARDIZATION C15956617 @IS02016 vided by IHS under I ted without license from IHS IS0 8278:2016(E) COPYRIGHTPROTECTEDDOCUMENT IS02016,PublishedinSwitzerland All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISO's member body in the country of the requester. ISO copyright office Ch. de Blandonnet 8 . CP 401 CH-1214 Vernier, Geneva, Switzerland Tel. +41 22 749 01 11 Fax+412274909 47 copyright@iso.org www.iso.org Intenationai br PrganizationforStandardization icensee-ZHEJIANG INST OF STANDARDIZoISQ s.6 - All rights reserved I by IHS unde etworking permitted without license from IHS IS0 8278:2016(E) Contents Page Foreword ..vi 1 Scope .1 2 Normative references 3 Terms and definitions 4 General requirements.. 4.1 Order of precedence. .. 6 4.2 Hydraulic system characteristics 4.3 Airworthiness requirements. 1 4.4 Qualification 7 5 Functional requirements 5.1 Hydraulic fluid. 7 5.2 Pump pressure 5.2.1 Rated discharge pressure .7 5.2.2 Maximum full-flow pressure .7 5.2.3 Pressure pulsations. .8 5.2.4 Inlet pressure. .8 5.3 Case drain pressure. .8 5.3.1 Rated case drain pressure .8 5.3.2 Maximum transient case drain pressure 5.3.3 Maximum case drain pressure. .8 5.4 Flows. .9 5.4.1 Pump rated discharge flow 9 5.4.2 Pump caseflow .9 5.4.3 Shaft seal leakage flow .9 5.4.4 External leakage .9 5.5 Speed and direction of rotation 10 5.5.1 Rated speed .10 5.5.2 Overspeed. ..10 5.5.3 Direction of rotation .10 5.6 Torque. 10 5.7 Pump overall efficiency .10 5.8 Variable delivery control 15 5.8.1 General. ..15 5.8.2 Adjustment. .15 5.8.3 Response time ..15 5.8.4 Stability .16 5.8.5 Maximum transient pressure. .17 5.9 Rated temperature.. ..17 5.10 Acoustic noise level. ..17 5.11 Endurance ..17 5.12 Environmental requirements. .18 6 Detail design requirements .18 6.1 Dimensionally critical components .18 6.2 Maintainability features. .18 6.3 Seals. .19 6.4 Lubrication .19 6.5 Balance .19 6.6 Self-contained failure .19 6.7 Safety wire sealing... .19 6.8 Electro-conductive bonding. ..19 6.9 Marking ..19 6.9.1 Nameplate ..19 iii ISee=ZHEJIANG INST OF STANDARDIZATION C1 5956617 ithout license from IHS