GMW-14786-2006.pdf
《GMW-14786-2006.pdf》由会员分享,可在线阅读,更多相关《GMW-14786-2006.pdf(5页珍藏版)》请在三一文库上搜索。
1、 WORLDWIDE ENGINEERING STANDARDS Test Procedure HVAC see Figure 1 and Figure 2. mm 1. Heater core 2. Connection for differential measurement line 3. Heater core out line 4. Heater core in line 5. Connection for differential measurement line Figure 1: T-fittings in Heater Core In and Out Line GMW1478
2、6 GM WORLDWIDE ENGINEERING STANDARDS Copyright 2006 General Motors Corporation All Rights Reserved Page 2 of 5 March 2006 8mmmm mm mm mm 1. Heater hose inside diameter 2. bore 4 equal space holes in ring duct, 2 mm Figure 2: T-fitting with Soldered on Ring Duct for Improved Pressure Measurement Note
3、: The four (4) bore holes in the ring duct shall be free from burrs but shall not be beveled. The installation of the flow meter and T-fittings can be seen in Figure 1 The differential pressure shall be measured in a straight part of the hose about = 120 mm in front of the heater core connection tub
4、es. 3.2.1.3 Differential pressure sensor. Attention shall be payed to a appropriate measurement range. The same instruments shall be used for the calibration of the pressure drop line chart of the heater core and the following measurement of the flow using the pressure drop line chart. 3.2.1.4 Engin
5、e speed sensor. Measuring device for gasoline and Diesel engines. 3.2.1.5 Temperature measuring device. Temperature measuring device to record coolant temperatures (3 measuring points). 3.2.1.6 Coolant. 50% antifreeze protection, 50% water. 3.2.2 Indirect Method using an External Test Bench. Test be
6、nch to determine. The equipment analogous to paragraphs 3.2.1.2 to 3.2.1.6 is required for the measurement of the differential pressure in the vehicle. 3.2.3 Indirect Measurement in the Vehicle. Equipment analogous paragraph 3.2.1. 3.3 Test Vehicle/Test Piece. Test vehicle equipped as specified or c
7、omplete engine block. 3.4 Test Time. Not applicable. 3.5 Test Required Information. Not applicable. 3.6 Personnel/Skills. Not applicable. 4 Procedure 4.1 Preparation. 4.1.1 Ensure that the vehicle engine and cooling systems correspond to preferred status. 4.1.2 Check that the correct heater core is
8、installed. 4.1.3 Install a tested thermostat. The opening values and leakage water quantity must remain within the specified tolerances. 4.1.4 Install temperature sensors: in the heater core in line and heater core out line in the radiator inlet to record the opening of the thermostat. 4.1.5 Install
9、ation of the two T-fittings to ascertain the pressure drop at the heater core. The T-fittings shall be inserted in a straight hose section about 120 mm in front of the heater core. If the heater core is connected by means of quick connections, these shall also be included in the measurement (partial
10、ly high resistance). 4.1.6 Install flow meter, if applicable. 4.1.7 Connect the differential pressure meter. -,-,- GM WORLDWIDE ENGINEERING STANDARDS GMW14786 Copyright 2006 General Motors Corporation All Rights Reserved March 2006 Page 3 of 5 4.1.8 Fill the cooling system with the provided coolant.
11、 Care shall be taken to ensure that no air enters the cooling-heating system during filling. In the case of critical systems, lack of air shall be checked by means of sight glasses in the heater circuit. 4.2 Conditions. 4.2.1 Environmental Conditions. 4.2.2 Test Conditions. Deviations from the requi
12、rements of the procedure shall have been agreed upon. Such requirements shall be specified on component drawings, test certificates, reports, etc. 4.3 Instructions. 4.3.1 Methods of Determining the Heater Flow. There are two methods to determine the heater flow: directly by means of a flow meter ind
13、irectly by means of differential pressure at a heater core, which characteristic pressure drop to coolant flow is known. Direct measurement using a flow meter is the most simple method, but is not always possible for reasons of space. Individual decisions must be made from case to case. Since the co
14、nfined space in some vehicle models does not allow measurements without major alterations to the hosing, the measurements may be per formed on an engine test bench or an engine block. 4.3.1.1 Direct measurement with flow meter and simultaneous recording of the static pressure drop at the heater core
15、. The flow meter shall be installed in the housing towards the heater core. If the installation of the flow meter generates major alterations (additional pressure drop) at the heating circuit, the indirect method described in paragraph 4.3.1.2 shall be employed. The static pressure drop at the heate
16、r core, possibly with quick connections, shall always be determined. For test assembly, see Figure 3. 4.3.1.2 Indirect measurement by measuring differential pressure at the heater core. In this test procedure, the heater flow V in dependency to the engine speed is ascertained indirectly by measuring
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- GMW 14786 2006
链接地址:https://www.31doc.com/p-3767570.html